US20230131317A1 - Ring cutter for safely transecting a ring trapped on an appendage - Google Patents

Abstract

A ring cutter for transecting a ring trapped on an appendage. The ring cutter includes a body, a motor housed in the body, a blade drivingly connected to the motor, a guard coupled to the body, a guard actuator drivingly connected to the guard and controlling a movement of the guard, a current sensor positioned to sense electrical current associated with the motor, and a processor communicatively coupled to the current sensor and the guard actuator. The blade has a rotation axis and a peripheral cutting edge. The guard is insertable between the ring and the appendage to position the ring between the guard and the blade. The processor is configured to: i) receive, from the current sensor, an electrical current reading associated with the motor, and ii) transmit, to the guard actuator, one or more commands to control the movement of the guard based on the electrical current reading.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS
• This application claims the benefit of priority to U.S. Provisional Application No. 63/270,763, filed Oct. 22, 2021, the contents of which is incorporated herein by reference in its entirety.
FIELD
• This disclosure relates generally to devices for removing stuck rings or other jewelry, and more particularly to ring cutters for safely transecting a ring trapped on an appendage (e.g., a digit, thumb, toe, or penis).
INTRODUCTION
• Removing hand/foot jewelry is commonplace in hospital emergency rooms around the world. Rings must be removed from the digits of patients in many, if not most cases where there is swelling of the digit, and/or swelling of the associated hand/foot or arm/leg. In cases where rings cannot be removed easily, the process of removal may be time-consuming, and in some cases may risk the health of the patient.
• In the event that a ring is not easily removable from a patient’s swollen digit, there are two widely accepted methods for removal of the ring: the ‘ring cutter method’ and the ‘string method’. In the ring cutter method, the ring is cut using e.g., a small rotary saw, and then mechanically deformed to remove it from the digit. In the string method, string, or an elastic constrictive material (e.g., a penrose drain) is wrapped tightly around a swollen digit to compress the digit, in an effort to decrease the swelling sufficiently so that the ring can be removed by sliding the ring towards and ultimately past the distal end of the digit.
SUMMARY
• The following introduction is provided to introduce the reader to the more detailed discussion to follow. The introduction is not intended to limit or define any claimed or as yet unclaimed invention. One or more inventions may reside in any combination or sub-combination of the elements or process steps disclosed in any part of this document including its claims and figures.
• In accordance with a broad aspect, there is provided a ring cutter for safely transecting a ring trapped on an appendage. The ring cutter includes: a) a body; b) a blade motor housed in the body; c) a circular blade drivingly connected to the blade motor, the blade having a blade rotation axis and a peripheral cutting edge; d) a guard coupled to the body and insertable between the ring and the appendage to position the ring between the guard and the blade; e) a guard actuator drivingly connected to the guard and controlling a movement of the guard; f) a current sensor positioned to sense electrical current associated with the blade motor; and g) one or more processors communicatively coupled to the current sensor and the guard actuator, wherein the one or more processors are configured to collectively:
• i) receive, from the current sensor, an electrical current reading associated with the blade motor, and
• ii) transmit, to the guard actuator, one or more commands to control the movement of the guard based at least on the electrical current reading.
• In accordance with another broad aspect, there is provided a ring cutter for safely transecting a ring trapped on an appendage. The ring cutter includes: a) a body; b) a blade motor housed in the body; c) a circular blade drivingly connected to the blade motor, the blade having a blade rotation axis and a peripheral cutting edge; d) a guard coupled to the body and insertable between the ring and the appendage to position the ring between the guard and the blade; e) a guard actuator drivingly connected to the guard and controlling a movement of the guard between at least a cutting start position and a cutting finished position; f) a position sensor located to sense a position associated with the guard; g) a cutting progress indicator associated with the movement of the guard between the cutting start and cutting finished positions; and h) one or more processors communicatively coupled to the position sensor and the cutting progress indicator, wherein the one or more processors are configured to collectively:
• i) receive, from the position sensor, a position signal associated with the guard; and
• ii) direct the cutting progress indicator to update based on the position signal.
• In accordance with another broad aspect, there is provided a ring cutter for safely transecting a ring trapped on an appendage. The ring cutter includes: a) a body; b) a blade motor housed in the body; c) a circular blade drivingly connected to the blade motor, the blade having a blade rotation axis and a peripheral cutting edge; d) a guard coupled to the body and insertable between the ring and the appendage to position the ring between the guard and the blade; e) a temperature sensor positioned to sense a temperature associate with the guard; and f) one or more processors communicatively coupled to the temperature sensor and the blade motor, wherein, the one or more processors are configured to collectively:
• i) receive, from the temperature sensor, a temperature reading associated with the guard, and
• ii) direct a speed of the blade motor based at least in part on the temperature reading.
• In accordance with another broad aspect, there is provided a ring cutter for safely transecting a ring trapped on an appendage. The ring cutter includes: a) a body; b) a blade motor housed in the body; c) a circular blade drivingly connected to the blade motor, the blade having a blade rotation axis and a peripheral cutting edge; d) a guard coupled to the body and insertable between the ring and the appendage to position the ring between the guard and the blade; e) a guard actuator drivingly connected to the guard and controlling a movement of the guard; f) a temperature sensor positioned to sense a temperature associated with the guard; and g) one or more processors communicatively coupled to the temperature sensor and the guard actuator, wherein, the one or more processors are configured to collectively:
• i) receive, from the temperature sensor, a temperature reading associated with the guard, and
• ii) transmit, to the guard actuator, one or more commands to control the movement of the guard based at least on the temperature reading.
• It will be appreciated by a person skilled in the art that an apparatus or method disclosed herein may embody any one or more of the features contained herein and that the features may be used in any particular combination or sub-combination.
• These and other aspects and features of various embodiments will be described in greater detail below.
BRIEF DESCRIPTION OF THE DRAWINGS
• For a better understanding of the described embodiments and to show more clearly how they may be carried into effect, reference will now be made, by way of example, to the accompanying drawings in which:
• FIG.1 is an example of a ring “stuck” on a swollen finger;
• FIG.2A is rear perspective view of a ring cutter, in accordance with an embodiment;
• FIGS.2B-2D are respective front perspective, side and rear views of the ring cutter ofFIG.2A;
• FIG.3 is a front perspective view of the ring cutter ofFIG.2A, with a first half of its outer shell removed;
• FIG.4 is a side perspective view of the ring cutter ofFIG.2A, with a second half of its outer shell removed;
• FIG.5 is an exploded view of a drive shaft, a blade, and a blade coupler of the ring cutter ofFIG.2A;
• FIGS.6A-6D are partial cross-sectional views of a ring positioned between a guard and cutting blade of the ring cutter ofFIG.2A, with the guard respectively shown in a guard insertion position, a start cutting position, a partially cut position, and a finished cutting position;
• FIG.7 is a schematic illustration of an electronic control system of the ring cutter ofFIG.2A;
• FIG.8 is a cross-sectional view of a ring cutter, in accordance with another embodiment;
• FIG.9 is a side view of a ring cutter, in accordance with another embodiment; and
• FIG.10 is a schematic illustration of a ring removal kit that includes a compression device and a ring cutter for respectively freeing and transecting a ring trapped on an appendage.
• The drawings included herewith are for illustrating various examples of articles, methods, and apparatuses of the teaching of the present specification and are not intended to limit the scope of what is taught in any way.
DESCRIPTION OF EXAMPLE EMBODIMENTS
• Various apparatuses, methods and compositions are described below to provide an example of an embodiment of each claimed invention. No embodiment described below limits any claimed invention and any claimed invention may cover apparatuses and methods that differ from those described below. The claimed inventions are not limited to apparatuses, methods and compositions having all of the features of any one apparatus, method or composition described below or to features common to multiple or all of the apparatuses, methods or compositions described below. It is possible that an apparatus, method or composition described below is not an embodiment of any claimed invention. Any invention disclosed in an apparatus, method or composition described below that is not claimed in this document may be the subject matter of another protective instrument, for example, a continuing patent application, and the applicant(s), inventor(s) and/or owner(s) do not intend to abandon, disclaim, or dedicate to the public any such invention by its disclosure in this document.
• Furthermore, it will be appreciated that for simplicity and clarity of illustration, where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous elements. In addition, numerous specific details are set forth in order to provide a thorough understanding of the example embodiments described herein. However, it will be understood by those of ordinary skill in the art that the example embodiments described herein may be practiced without these specific details. In other instances, well-known methods, procedures, and components have not been described in detail so as not to obscure the example embodiments described herein. Also, the description is not to be considered as limiting the scope of the example embodiments described herein.
• The terms “an embodiment”, “embodiment”, “embodiments”, “the embodiment”, “the embodiments”, “one or more embodiments”, “some embodiments”, and “one embodiment” mean “one or more (but not all) embodiments of the present invention(s)”, unless expressly specified otherwise.
• The terms “including”, “comprising”, and variations thereof mean “including but not limited to”, unless expressly specified otherwise. A listing of items does not imply that any or all of the items are mutually exclusive, unless expressly specified otherwise. The terms “a”, “an”, and “the” mean “one or more”, unless expressly specified otherwise.
• As used herein and in the claims, two or more parts are said to be “coupled”, “connected”, “attached”, “joined”, “affixed”, or “fastened” where the parts are joined or operate together either directly or indirectly (i.e., through one or more intermediate parts), so long as a link occurs. As used herein and in the claims, two or more parts are said to be “directly coupled”, “directly connected”, “directly attached”, “directly joined”, “directly affixed”, or “directly fastened” where the parts are connected in physical contact with each other. As used herein, two or more parts are said to be “rigidly coupled”, “rigidly connected”, “rigidly attached”, “rigidly joined”, “rigidly affixed”, or “rigidly fastened” where the parts are coupled so as to move as one while maintaining a constant orientation relative to each other. None of the terms “coupled”, “connected”, “attached”, “joined”, “affixed”, and “fastened” distinguish the manner in which two or more parts are joined together.
• Further, although method steps may be described (in the disclosure and / or in the claims) in a sequential order, such methods may be configured to work in alternate orders. In other words, any sequence or order of steps that may be described does not necessarily indicate a requirement that the steps be performed in that order. The steps of methods described herein may be performed in any order that is practical. Further, some steps may be performed simultaneously.
• As used herein and in the claims, a first element is said to be ‘communicatively coupled to’ or ‘communicatively connected to’ or ‘connected in communication with’ a second element where the first element is configured to send or receive electronic signals (e.g., data) to or from the second element, and the second element is configured to receive or send the electronic signals from or to the first element. The communication may be wired (e.g., the first and second elements are connected by one or more data cables), or wireless (e.g., at least one of the first and second elements has a wireless transmitter, and at least the other of the first and second elements has a wireless receiver). The electronic signals may be analog or digital. The communication may be one-way or two-way. In some cases, the communication may conform to one or more standard protocols (e.g., SPI, I²C, Bluetooth™, or IEEE™ 802.11).
• As used herein and in the claims, a group of elements are said to ‘collectively’ perform an act where that act is performed by any one of the elements in the group, or performed cooperatively by two or more (or all) elements in the group.
• Some elements herein may be identified by a part number, which is composed of a base number followed by an alphabetical or subscript-numerical suffix (e.g., 112a, or 112₁). Multiple elements herein may be identified by part numbers that share a base number in common and that differ by their suffixes (e.g., 112₁, 112₂, and 112₃). All elements with a common base number may be referred to collectively or generically using the base number without a suffix (e.g.,112).
• Removing jewelry trapped on appendages is commonplace in hospital emergency rooms around the world. As an example,FIG.1 depicts aring10 that is ‘stuck’ on aswollen finger20, in that it cannot be removed by pulling or otherwise mechanically urging the ring towards the distal end of the finger without injuring the finger and/or causing significant pain or discomfort. In other cases, a ring or band may become stuck on different appendages, such as, e.g., thumbs, toes, and genitalia (e.g. penis). Rings must be removed from such appendages in many, if not most cases where there is swelling of that appendage.
• FIGS.2A-2D illustrate a ring cutter, referred to generally as100, that may be used to safely transect a ring trapped on an appendage. Thering cutter100 has opposed front andrear ends110,112, and opposed upper and lower ends114,116. As shown, thering cutter100 includes abody102, a blade motor104 (FIG.3) housed in thebody102, acircular blade106 drivingly connected to theblade motor104, and anappendage guard108 coupled to thebody102.
• Theblade106 has ablade rotation axis118 and aperipheral cutting edge120. Rotation of theblade106 about theblade rotation axis118 is driven by theblade motor104. Theblade106 may be provided in any suitable position for cutting. In the illustrated embodiment, theblade106 is positioned proximate to thefront end110 of thering cutter100. Such arrangement may improve safety as it locates theblade106 away from the operator. Theblade106 may have any suitable diameter. In some embodiments, the blade diameter may be between 5 and 100 mm. Preferably, the blade diameter is between10 and 50 mm, and more preferably between20 and 30 mm.
• In the illustrated embodiment, thebody102 includes a recessedportion122 in which theblade106 is seated. As shown inFIG.2B, thebody102 has upper, front, and rear blade shields124,126,128 that partially bound the recessedportion122 and extend past the plane of theblade106. Accordingly, positioning theblade106 in the recessedportion122 may protect the patient and/or operator from making inadvertent contact with theperipheral cutting edge120 of the blade106 (i.e., the upper, front, and rear blade shields124,126,128 may block such inadvertent contact). The recessedportion122 of thebody102 may also protect theblade106 from damage in the event thering cutter100 is dropped. In alternative embodiments, thebody102 may not include a recessedportion122 for theblade106.
• Theguard108 is insertable between a ring and an appendage to position the ring between theguard108 and theblade106. As an example, theguard108 may be inserted between thering10 that is stuck on the swollen finger20 (e.g., seeFIG.1). Once theguard108 is inserted, thering10 is positioned between theguard108 and theperipheral cutting edge120 of theblade106. In such an arrangement, movement of theguard108 toward theblade106 moves thering10 towards theblade106. During a cutting process, theguard108 can be moved relative to theblade106 to supply a cutting pressure between thering10 and the blade106 (i.e., theguard108 presses thering10 into theperipheral cutting edge120 of the blade106). Theguard108 can be moved toward theblade106 to increase the applied cutting pressure or away from theblade106 to decrease the applied cutting pressure. Owing to its position between the appendage and theblade106, theguard108 protects the appendage from being cut by theblade106.
• In some embodiments, theguard108 may be moved manually toward or away from theblade106. For example, the operator may supply a force to theguard108 that causes theguard108 to move toward or away from theblade106 depending on the direction of the force. Alternatively, or in addition, theguard108 may be moved manually via user interaction with a remote lever, slider, trigger, knob, or the like. In other embodiments, theguard108 is not manually movable.
• Theguard108 can be connected to thebody102 in any manner that allows theguard108 to be moved toward and away from theperipheral cutting edge120 of theblade106. For example, theguard108 may be connected to thebody102 in a manner that allowsguard108 to translate (e.g., slide) or rotate (e.g., pivot) toward and away from theperipheral cutting edge120. In one embodiment, theguard108 may be connected to thebody102 by a telescopic cylinder (not shown) that is moveable (e.g., in translation) between retracted and extended positions. In this embodiment, the movement of the telescopic cylinder between the retracted and extended positions moves theguard108 toward and away from theperipheral cutting edge120 of theblade106.
• In the illustrated embodiment, theguard108 is pivotably connected to thebody102. As shown, theguard108 has a guardproximal end130 pivotably connected to thebody102 at aguard pivot axis132, and a guarddistal end134 spaced apart from the guardproximal end130. The guarddistal end134 is insertable between the ring and the appendage to position the ring between theguard108 and theblade106. Pivoting theguard108 about theguard pivot axis132, toward theblade106, moves the guarddistal end134 closer to theperipheral cutting edge120 of theblade106. Conversely, pivoting theguard108 about theguard pivot axis132, away from theblade106, moves the guarddistal end134 away from theperipheral cutting edge120 of theblade106.
• Referring toFIG.2C, theguard108 is pivotable about theguard pivot axis132 in aguard closing direction136 and an opposed guard opening direction138. Pivoting theguard108 in theguard closing direction136 moves the guarddistal end134 toward theperipheral cutting edge120 of theblade106. Theguard108 may be pivoted in theguard closing direction136 to increase the pressure between the ring and theperipheral cutting edge120 of theblade106. Conversely, pivoting theguard108 in the guard opening direction138 moves the guarddistal end134 away from theperipheral cutting edge120 of theblade106. Theguard108 may be pivoted in the guard opening direction138 to decrease the pressure between the ring and theperipheral cutting edge120 of theblade106.
• In some embodiments, theguard108 may be pivoted manually about the guard pivot axis132 (i.e., in either the guard closing and openingdirections136,138). For example, an operator may supply a force to theguard108 that causes theguard108 to pivot about theguard pivot axis132. Alternatively, or in addition, a resiliently elastic member (e.g., torsion spring, not shown) may be positioned to assist pivoting theguard108 about theguard pivot axis132. For example, the torsion spring may bias theguard108 toward the guard closing direction136 (i.e., when force is removed from theguard108, theguard108 pivots in the guard closing direction136). To pivot theguard108 in the guard opening direction138, the operator may supply a force to theguard108 sufficient to overcome the opposed spring bias. In alternative embodiments, theguard108 cannot be manually pivoted about theguard pivot axis132.
• Referring toFIG.4, thering cutter100 as illustrated includes aguard actuator140 that is drivingly connected to theguard108. Theguard actuator140 can control movement of theguard108. As shown, theguard actuator140 includes anactuator housing142, an arm144 movably connected to theactuator housing142, and a linkage146 having a linkupper end148 and an opposed linklower end150. The linkupper end148 is pivotably connected to the arm144 while the linklower end150 is rigidly connected to aguard axle152. The linkage146 rotates in response to actuation of the arm144, which in turn causes theguard axle152 to rotate. Theguard axle152 is rigidly connected to the guardproximal end130 so that rotation of theguard axle152 causes theguard108 to pivot about theguard pivot axis132. In effect, actuation of the arm144 causes theguard108 to pivot about theguard pivot axis132.
• As the arm144 moves outwardly of the actuator housing142 (i.e., in an arm extending direction154), theguard108 is pivoted about theguard pivot axis132 in the guard opening direction138 (FIG.2C). As described above, pivoting theguard108 in the guard opening direction138 causes the guarddistal end134 to move away from theperipheral cutting edge120 of theblade106. Conversely, as the arm144 moves inwardly of the actuator housing142 (i.e., in an arm retracting direction156), theguard108 is pivoted about theguard pivot axis132 in the guard closing direction136 (FIG.2C). As described above, pivoting theguard108 in theguard closing direction136 causes the guarddistal end134 to move closer to theperipheral cutting edge120 of theblade106.
• Any type of guard actuator that can pivot theguard108 in the guard closing and openingdirections136,138 may be used in thering cutter100. In the illustrated embodiment, theguard actuator140 is a linear actuator (i.e., the arm144 moves along a linear pathway). In an alternative embodiment, theguard actuator140 may be a rotary actuator (e.g., motor). In this embodiment, the rotary actuator may be drivingly connected to theguard108 directly, or indirectly (e.g., through theguard axle152, by way of gear(s) and/or belt(s)).
• Theguard108 may have any configuration that allows it to be inserted between a trapped ring and the appendage that ring is trapped on. For example, theguard108 may be a straight or curved arm. The guarddistal end134 is preferably kept thin to facilitate inserting theguard108 between the ring and the appendage from the guarddistal end134. Theguard108 can be made of any rigid material. Preferably, theguard108 is made of a bio-compatible, high thermal capacity material (e.g., titanium, stainless steel, etc.) so that any heat generated during a cutting process is first dissipated into theguard108. The extent to which theguard108 can dissipate the heat generated during the cutting process reduces the heat generated that may be transferred to the appendage.
• In the illustrated embodiment, theguard108 includes a guarddistal segment158. The guarddistal segment158 has the guarddistal end134. As shown inFIGS.2B and2C, the guarddistal segment158 includes aring abutment ledge160 and acurved ring lever162 that extends distally from thering abutment ledge160. Thecurved ring lever162 is insertable between the ring and the appendage to position the ring against thering abutment ledge160. As shown inFIG.6A, a portion of the guarddistal segment158 extends past thering10 when thering10 is positioned against thering abutment ledge160. The depressed shaped of thecurved ring lever162 may help keep thering10 in contact with thering abutment ledge160 during a cutting process, and thereby limit ring movement. Movement of thering10 during the cutting process can reduce cutting efficiency, as well as cause discomfort and/or injury to the patient.
• Referring toFIG.3, theblade motor104 has a motor rotation axis164 that extends longitudinally (e.g., in a direction that intersects the front andrear ends110,112 of the ring cutter100). In the illustrated embodiment, each of theblade rotation axis118 and theguard pivot axis132 extend laterally. Having theblade rotation axis118 and theguard pivoting axis132 extend laterally while the motor rotation axis164 extends longitudinally can allow easier access to the ring being cut. Such a configuration is particularly advantageous in cases where the ring is stuck in a sensitive area (e.g., genitalia).
• As exemplified inFIG.3, the motor rotation axis164 may extend transverse to theblade rotation axis118. As used herein, “transverse” means within 45 degrees of perpendicular. To drivingly connect theblade motor104 to theblade106 with ablade rotation axis118 that extends transverse to the motor rotation axis164, one or more power transmission component(s) (e.g., worm gear, bevel gear, chain, belt, or the like) can be positioned between theblade motor104 and theblade106. In the illustrated embodiment, theblade rotation axis118 extends perpendicularly to the motor rotation axis164. This configuration can permit the operator to orient thering cutter100 so that thebody102 extends generally parallel to the appendage on which the ring is trapped. By aligning thebody102 with the appendage (e.g., finger or toe), obstruction caused by other nearby digits and/or body parts may be limited. As a result, thering cutter100 may be able to access and cut rings that are trapped in areas that would otherwise be difficult to access.
• Referring still toFIG.4, theblade motor104 is drivingly connected to theblade106 through intermeshedbevel gears 166₁, 166₂. Thebevel gear 166₂ is rigidly connected to adrive shaft168 such that rotation of thebevel gear 166₂ causes rotation of thedrive shaft168. Rotation of theblade motor104 about the motor rotation axis164 drives rotation of thebevel gear 166₁ about the motor rotation axis164, which in turn causes thebevel gear 166₂ and thedrive shaft168 to rotate about theblade rotation axis118. Thedrive shaft168 is rigidly connected to theblade108 such that rotation of thedrive shaft168 causes rotation of theblade106. In effect, the bevel gears 166₁, 166₂ facilitate power transmission between the perpendicularly aligned rotation axes of theblade motor104 and theblade106.
• As exemplified inFIG.5, theblade106 may be removably connected to thedrive shaft168. This can allow a usedblade106 to be replaced with afresh blade106 between uses. Theblade106 may be removably connected to thedrive shaft168 in a manner that provides a secure and releasable connection, e.g., mechanical fasteners. In the illustrated embodiment ofFIG.5, thedrive shaft168 includes a blade interface170 and a threadedend portion172 that extends distally from the blade interface170. As shown, theblade106 includes a central aperture174 that corresponds with the blade interface170 of thedrive shaft168. The corresponding mating shapes of the blade interface170 and the central aperture174 help ensure theblade106 is axially aligned with thedrive shaft168 when installed (i.e., limits misalignments which may cause blade fractures).
• To connect theblade106 to thedrive shaft168, the threadedend portion172 of the drive shaft is passed through the central aperture174 of theblade106 until the central aperture174 mates with the blade interface170. Ablade retaining member176 is then threadedly engaged with the threadedend portion172 of thedrive shaft168 and tightened to provide a clamping force which sandwiches theblade106 between the retainingmember176 and thedrive shaft168. To remove theblade106 from thedrive shaft168, the above-described process can be performed in reverse.
• Referring again toFIGS.2A-2D, thering cutter100 can include ahandle178 for the operator to grasp during cutting operations. Thehandle178 may have various positional arrangements and configurations, which improve the ergonomics of thering cutter100. As exemplified inFIGS.2A-2D, thehandle178 may be provided at thelower end116 of thering cutter100. As another example, thehandle178 may be located at therear end112 of the ring cutter100 (e.g., seeFIG.8). As another yet example, thehandle178 may be located at theupper end114 of thering cutter100. Optionally, thehandle178 may be removable from thebody102. Thehandle178 can be removably mounted to thebody102 in any suitable fashion (e.g., dove-tail locking members, clips, etc.). In an alternative embodiment, thering cutter100 may not include a handle (e.g., seeFIG.9).
• Thehandle178 may have various configurations. For example, thehandle178 may be configured as a stick or linearly extending handle. In the illustrated embodiment shown inFIGS.2A-2D, thehandle178 is configured as a pistol grip type handle. As shown, when thering cutter100 is oriented so that theupper end114 is above thelower end116, the pistol grip handle178 extends upwardly and forwardly along a handle axis180 (FIG.2C) between handle upper and lower ends182,184. The handleupper end182 is mounted to thebody102. When thering cutter100 is oriented with theupper end114 positioned above thelower end116, thebody102 has a bodyupper surface186 and a body lower surface188. As shown inFIG.2C, the handleupper end182 is mounted to the body lower surface188.
• As exemplified inFIGS.2A-2D, a restingbase190 may be provided at the handlelower end184. The restingbase190 may extend outboard of the handlelower end184. The restingbase190 is engageable with a ring cutter support surface (e.g., a table, workbench, or other suitable support surface). Engaging the restingbase190 with a support surface can provide for one or more advantages during a cutting process. For example, the positioning of the restingbase190 on a support surface allows that support surface to bear at least a portion of the ring cutter’s weight. This may reduce operator fatigue because the operator no longer must support the whole weight of thering cutter100 during the cutting process. Alternatively, or in addition, engagement of the restingbase190 with a support surface may enhance the stability of thering cutter100 during the cutting process (e.g., limit lateral movement of the guard108). Lateral movement of theguard108 relative to the ring and finger during the cutting process can cause bruising and discomfort to the patient.
• The restingbase190 as illustrated extends outboard of the handlelower end184 around the full handle perimeter. That is, the restingbase190 extends both forwardly and rearwardly of the handle lower end184 (seeFIG.2C) and laterally outwardly from both sides of the handle lower end184 (seeFIG.2D). This configuration may improve stability. In alternative embodiments, the restingbase190 may only extend forwardly and rearwardly of the handlelower end184. In another alternative embodiment, the restingbase190 may only extend laterally from one side of the handlelower end184. In alternative embodiments, thering cutter100 may not include a resting base.
• Power may be supplied to theblade motor104 and other electrical components of thering cutter100 from one or more energy storage members. In the illustrated embodiment, thering cutter100 includes an onboardenergy storage member192. The schematic ofFIG.7 illustrates the connection of theblade motor104 and theenergy storage member192. Theenergy storage member192 may include, for example, batteries, supercapacitors, or the like. Theenergy storage member192 may be permanently mounted in thering cutter100 and rechargeable in-situ, and/or removable from the ring cutter100 (e.g., theenergy storage member192 may be removably mounted to thering cutter100. Theenergy storage member192 may be recharged in-situ by connecting one end of an electrical cord to a cord port194 (FIGS.2A and2D) while the other end of the electrical cord is connected to mains power at a standard wall electrical outlet.
• The onboardenergy storage member192 may have various positional arrangements, which may improve the ergonomics of the ring cutter100 (e.g., reduced weight, better weight balance or greater portability). As an example, theenergy storage member192 may be housed in thebody102 and located rearwardly of theblade motor104. As another example, theenergy storage member192 may be positioned within thehandle178. In the illustrated embodiment, theenergy storage member192 is provided at the handlelower end184. As shown, theenergy storage member192 is housed in theresting base190.
• In alternative embodiments, thering cutter100 may not include an onboard energy storage member. For example, power may be supplied to theblade motor104 and other electrical components of thering cutter100 by an electrical cord connected to thering cutter100. The electrical cord can be connected to mains power at a standard wall electrical outlet.
• Reference is now made toFIGS.6A-6D to illustrate an exemplary movement of theguard108 throughout a ring cutting process. The guard actuator140 (FIG.4) may control pivoting of theguard108 into the various positions described below. Alternatively, or in addition, an operator may manually pivot theguard108 by supplying a force to theguard108. As explained below, theguard108 as illustrated is pivotable about theguard pivot axis132 between a guard insertion position (FIG.6A) and a cutting finished position (FIG.6D). Theguard108 passes through a cutting start position (FIG.6B) and a partially cut position (FIG.6C) as it pivots from the guard insertion position to the cutting finished position.
• FIG.6A shows theguard108 in the guard insertion position. In the guard insertion position, theguard108 is pivoted about theguard pivot axis132 to provide aninsertion gap196 between theperipheral cutting edge120 of theblade106 and the guarddistal end134. As exemplified, theinsertion gap196 is at least slightly larger than the cross-sectional thickness of thering10. Accordingly, when theguard108 is in the guard insertion position, theinsertion gap196 may facilitate the insertion of the guarddistal end134 between thering10 and theperipheral cutting edge120.
• FIG.6B shows theguard108 in the cutting start position. In the cutting start position, theguard108 is pivoted about theguard pivot axis132 so that thering10 contacts theperipheral cutting edge120 of theblade106. In this position, theblade motor104 can be activated to initiate rotation of theblade106 about the blade rotation axis118 (FIG.2A). Comparing the cutting start position ofFIG.6B to the guard insertion position ofFIG.6A shows that the guarddistal end134 has moved closer to theperipheral cutting edge120 of the blade106 (i.e., due to pivoting of theguard108 about theguard pivot axis132 in the guard closing direction136).
• FIG.6C shows theguard108 in the partially cut position. As shown, theblade106 has partially cut through thering10. Comparing the partially cut position ofFIG.6C to the cutting start position ofFIG.6B shows that the guarddistal end134 has moved even closer to theperipheral cutting edge120 of the blade106 (i.e., due to pivoting of theguard108 about theguard pivot axis132 in the guard closing direction136).
• FIG.6D shows the guard in the cutting finished position. As shown, theblade106 has completely transected (i.e., cut through) thering10. Once thering10 is transected, it can be spread apart and removed from the appendage. In some cases, a ring spreader may be used to simplify spreading apart the transected ring for removal. Comparing the cutting finished position ofFIG.6D to the partially cut position ofFIG.6C shows that the guarddistal end134 has moved even closer to theperipheral cutting edge120 of the blade106 (i.e., due to pivoting of theguard108 about theguard pivot axis132 in the guard closing direction136).
• As theguard108 pivots from the cutting start position (FIG.6B) to the cutting finished position (FIG.6D), it supplies a force to thering10 that presses thering10 into theperipheral cutting edge120 of theblade106.
• As described above, by virtue of its position between the appendage and theblade106, theguard108 can protect the appendage (e.g., finger or toe) from being cut by theblade106. Preferably, theguard108 is unable to contact theperipheral cutting edge120 when the guard is in the cutting finished position. This can increase patient safety as theblade106 may be physically unable to cut through theguard108 and into the appendage.
• In one embodiment, theguard108 may be inhibited from pivoting toward theperipheral cutting edge120 when in the cutting finished position. There are various ways theguard108 may be inhibited from pivoting toward theperipheral cutting edge120 when in the cutting finished position. For example, a pivot stop may be positioned to project into the pivot pathway of theguard108 and obstruct theguard108 from pivoting any farther in theguard closing direction136. In the illustrated example, theguard actuator140 bottoms out when theguard108 is the cutting finished position (i.e., the arm144 is fully retracted when theguard108 is in the cutting finished position).
• Reference is made toFIG.7, which shows a schematic illustration of an exampleelectronic control system200 of thering cutter100. In the example shown,electronic control system200 includes aprocessor202, amemory204, a communication module206, a user-operablemotor activation switch208, a user operable guard adjustment input210, acurrent sensor212, aposition sensor214, and a temperature sensor216. Each of thememory204, the communication module206, themotor activation switch208, the guard adjustment input210, thecurrent sensor212, theposition sensor214, and the temperature sensor216 are communicatively coupled to theprocessor202, directly or indirectly.
• In some embodiments, theelectronic control system200 includes multiple of any one or more of theprocessor202, thememory204, the communication module206, themotor activation switch208, the guard adjustment input210, thecurrent sensor212, theposition sensor214, and the temperature sensor216. In some embodiments,electronic control system200 does not include one or more of thememory204, the communication module206, themotor activation switch208, the guard adjustment input210, thecurrent sensor212, theposition sensor214, and the temperature sensor216. For example, theelectronic control system200 may not include thememory204, and/or may not include the communication module206, and/or may not include themotor activation switch208 and/or may not include the guard adjustment input210, and/or may not include thecurrent sensor212, and/or may not include theposition sensor214, and/or may not include the temperature sensor216.
• In some embodiments, theelectronic control system200 is a single, unitary device that houses all of its subcomponents (theprocessor202, thememory204, etc.). In other embodiments,electronic control system200 is composed of two or more discrete subdevices that are communicatively coupled to each other, that collectively include all of the subcomponents of electronic control system200 (theprocessor202, thememory204, etc.), and that collectively provide the functionality described herein.
• The schematic ofFIG.7 illustrates the connection of theelectrical control system200 to theblade motor104, theguard actuator140, a cuttingprogress indicator218, and alubrication indicator228. Each of theblade motor104, theguard actuator140, the cuttingprogress indicator218, and thelubrication indicator228 may be connected to theelectrical control system200 through a wired connection (e.g., USB, JTAG, FTDI, etc.) or a wireless connection (e.g., wireless access network, Bluetooth®, etc.). These connections can allow theelectronic control system200 to communicate and/or relay signals with each of theblade motor104, theguard actuator140, the cuttingprogress indicator218, and thelubrication indicator228.
• Thememory204 can include random access memory (RAM), read only memory (ROM), or similar types of memory. Also, in some embodiments, thememory204 stores one or more applications for execution by theprocessor202. Applications correspond with software modules including computer executable instructions to perform processing for the functions and methods described below. In some embodiments, some or all of thememory204 may be integrated with theprocessor202. For example, theprocessor202 may be a microcontroller (e.g., Microchip™ AVR, Microchip™ PIC, or ARM™ microcontroller) with onboard volatile and/or non-volatile memory.
• Theprocessor202 may have numerous I/O ports that may be communicatively coupled to one or more (or all) of thememory204, the communication module206, themotor activation switch208, the guard adjustment input210, thecurrent sensor212, theposition sensor214 and the temperature sensor216, for example. Theprocessor202 may communicate with each subcomponent (e.g., thememory204, thecurrent sensor212, etc.) by wire or wirelessly. Subcomponents may be communicatively coupled to theprocessor202 by cables and/or PCB traces, for example.
• Generally, theprocessor202 can execute computer readable instructions (also referred to as applications or programs). The computer readable instructions can be stored in thememory204. When executed, the computer readable instructions can configure the processor202 (ormultiple processors202, collectively) to perform the acts described herein with reference toring cutter100, for example.
• The communication module206 can include any device capable of transmitting signals to and/or receiving signals from an external device. For example, the communication module206 may include radios that communicate utilizing the CDMA, GSM, GPRS, NFC, or Bluetooth® protocol according to such standards as 802.11 a, 802.11 b, 802.11 g or 802.11n, for example. Alternatively, or in addition, the communication module206 may include one or more USB ports for wired connections with external devices.
• Thecurrent sensor212 may be any device capable of measuring an electrical current associated with theblade motor104. Thecurrent sensor212 may communicate electrical current readings (by wire or wirelessly) to theprocessor202, which may determine whether the current readings satisfy criteria associated with predetermined cutting parameters. Signals (i.e., information) from thecurrent sensor212 may be referred to as “current readings”. Thecurrent sensor212 may be positioned in any suitable location for sensing an electrical current associated with theblade motor104. In one example, thecurrent sensor212 may be positioned upstream of the electrical current flowing into theblade motor104. In this position, thecurrent sensor212 can sense the electrical current drawn by theblade motor104. Alternatively, or in addition, thecurrent sensor212 may be positioned between theblade motor104 and theenergy storage member192. In this position, thecurrent sensor212 can sense the electrical current passing from theenergy storage member192 to theblade motor104.
• Theposition sensor214 may be any device capable of measuring a position associated with theguard108. Theposition sensor214 may include, for example one or more (or all) of a potentiometer (linear or rotary), a hall effect sensor, an accelerometer, a gyroscope, and a magnetometer. Theposition sensor214 may communicate position readings (by wire or wirelessly) to theprocessor202, which may determine whether the position readings require the cuttingprogress indicator218 to be updated. Signals (i.e., information) from aposition sensor214 may be referred to as “position readings”. Theposition sensor214 may be positioned in any suitable location for sensing a position associated with theguard108.
• In the embodiment ofFIG.4, theposition sensor214 is shown on the arm144 of theguard actuator140. In this location, theposition sensor214 may sense a position of theguard actuator140. For example, a linear potentiometer may be used to measure the absolute position of the arm144. As described above with reference toFIG.4, the position (i.e., actuation) of the arm144 dictates the position of theguard108. Upon receiving a position signal from theposition sensor214, theprocessor202 may be configured to associate the position of theguard actuator140 with a position of theguard108. For example, theprocessor202 may consult a lookup table of corresponding guard positions for each actuator position (i.e., each actuator step).
• The temperature sensor216 may be any device capable of measuring a temperature associated with theguard108. The temperature sensor216 may communicate temperature readings (by wire or wirelessly) to theprocessor202, which may determine whether the temperature readings satisfy criteria associated with a safety protocol. Signals (i.e., information) from the temperature sensor216 may be referred to as “temperature readings”. The temperature sensor216 may be positioned in any suitable location for sensing a temperature associated with theguard108. For example, inFIG.4, the temperature sensor216 is shown positioned on the underside of theguard108. In this position, the temperature sensor216 can sense the temperature of theguard108 where it contacts the appendage. It may be preferable to locate the temperature sensor216 proximate the part of theguard108 that contacts the ring during cutting because this is where the generated heat first dissipates.
• FIG.7 illustrates one example hardware schematic of anelectronic control system200 that may be used with thering cutter100. In alternative embodiments,electronic control system200 contains fewer, additional, or different components. In addition, although aspects of an implementation ofelectronic control system200 are described as being stored in memory, one skilled in the art will appreciate that these aspects can also be stored on or read from other types of computer program products or computer-readable media (e.g., a non-transitory computer-readable medium), such as secondary storage devices, including hard disks, floppy disks, CDs, or DVDs; a carrier wave from the Internet or other network; or other forms of RAM or ROM.
• Thering cutter100 may include amotor activation switch208 that is provided to selectively control the operation of the blade motor104 (e.g., either on/off or variable power levels or both), for example by establishing a power connection betweenenergy storage member192 and theblade motor104.Motor activation switch208 may be provided in any suitable location and include any input device that can be manually operated (i.e., operation by interaction with an operator’s body part. For example, themotor activation switch208 may include one or more tactile or capacitive buttons, rotary switches, sliding switches, trigger-type actuators, control knobs, or touchscreens. As an example,FIGS.2A-2C show themotor activation switch208 provided as a trigger-type actuator proximate the handleupper end182. In this configuration, thetrigger208 can be actuated (i.e.., squeezed) with the index or middle finger of the hand used to grip thehandle178.
• Theprocessor202 is configured to activate and/or deactivate theblade motor104 in response to user interaction with themotor activation switch208. In some cases, theblade motor104 may remain active (i.e., continue to run) until the user interaction is removed from the motor activation switch208 (e.g., until the trigger is released). In other cases, theblade motor104 may remain active between first and second user interactions with motor activation switch208 (i.e., the first user interaction turns theblade motor104 on and the second user interaction turns theblade motor104 off).
• As described above with reference toFIG.6A, theguard108 is pivotable about theguard pivot axis132 to a guard insertion position. When theguard108 is in the guard insertion position, theinsertion gap196 may facilitate the insertion of the guarddistal end134 between thering10 and theperipheral cutting edge120 of theblade106. Thering cutter100 may include a guard adjustment input210 to manually control movement of theguard108 between the guard insertion position (e.g.,FIG.6A) and the cutting start position (e.g.,FIG.6B). Theprocessor202 may be configured to direct theguard actuator140 to pivot theguard108 about theguard pivot axis132 between the guard insertion position and the cutting start position in response to user interaction with the guard adjustment input210.
• The guard adjustment input210 may be provided in any suitable configuration and include any input device that can be manually operated (i.e., operation by interaction with an operator’s body part). For example, the guard adjustment input210 may include one or more tactile or capacitive buttons, switches, sliders, control knobs, or touchscreens. As an example,FIG.2D shows the guard adjustment input210 provided as a toggle switch on the rear end of thebody102. Pressing the toggle switch210 up pivots theguard108 in theguard closing direction136. An operator may press the toggle switch210 up to pivot theguard108 from the guard insertion position (e.g.,FIG.6A) to the cutting start position (e.g.,FIG.6B). This may be done once the operator has inserted theguard108 between the trapped ring and the appendage and is ready to begin cutting. Conversely, pressing the toggle switch210 down pivots theguard108 in the guard opening direction138. In alternative embodiments, the directions of the toggle switch210 may be reversed.
• In some embodiments, thering cutter100 may include an electronic control system200 (FIG.7) that can automatically adjust the position of theguard108 based on an electrical current reading associated with theblade motor104.
• The electrical current reading associated with theblade motor104 can be used to approximate the torque applied to the blade106 (also referred to herein as blade torque). The blade torque and the electrical current associated with theblade motor104 are positively correlated. Accordingly, all else being equal, the electrical current associated with theblade motor104 increases as the blade torque increases. This is because the electrical current drawn by theblade motor104 increases as the blade torque increases (i.e., theblade motor104 requires more current to operate at a higher load). Maintaining a stable blade torque during the cutting process can provide one or more advantages. For example, a stable blade torque can provide a consistent cutting performance across rings of various cross-sectional size and material. Alternatively, or in addition, maintaining a stable blade torque may help protect the user from excessive heat generation (e.g., that may be caused by excessive torque) and/or may help protect theblade motor104 from overheating or burning out.
• Referring still toFIG.7, theprocessor202 may be configured to receive, from thecurrent sensor212, an electrical current reading associated with theblade motor104, and transmit, to theguard actuator140, one or more commands to control the movement of theguard108 based at least on the electrical current reading. For example, theprocessor202 may transmit commands instructing theguard actuator140 to move in response to current criteria. Current criteria may include that the electrical current reading (a) exceeds a threshold value, (b) falls below a threshold value, (c) lies outside a predetermined value range, (d) has increased faster than a threshold rate, (e) has decreased faster than a threshold rate, and/or (f) maintains a specific value for a predetermined amount of time or motor revolutions.
• In one embodiment, theguard actuator140 can control a movement speed of theguard108 toward theperipheral cutting edge120 of theblade106 in response to commands from theprocessor202 sent based on electrical current readings and current criteria. In this embodiment, theprocessor202 may be configured to determine that the electrical current reading is low based on current criteria (e.g., falls below a threshold value, is below a predetermined value range, or has decreased faster than a threshold rate), and direct theguard actuator140 to increase the movement speed of theguard108 toward theperipheral cutting edge120. Increasing the movement speed of theguard108 towards theperipheral cutting edge120 will increase the rate at which the ring is cut. This in turn can increase the blade torque and result in an increased current draw by theblade motor104.
• Alternatively, or in addition to increasing the movement speed based on low electrical current reading, theprocessor202 may be configured to determine that the electrical current reading is high based on current criteria (e.g., exceeds a threshold value, is above a predetermined value range, or has increased faster than a threshold rate), and direct theguard actuator140 to decrease the movement speed of theguard108 toward theperipheral cutting edge120. Decreasing the movement speed of theguard108 towards theperipheral cutting edge120 will decrease the rate at which the ring is cut. This in turn can decrease the blade torque and result in a decreased current draw by theblade motor104.
• Alternatively, or in addition, theprocessor202 may be configured to determine that the electrical current reading is low and/or high based on current criteria, and control a pivoting of theguard108 about theguard pivot axis132 to move theguard108 toward (if low) or away (if high) from theperipheral cutting edge120 of theblade106.
• Alternatively, or in addition, theprocessor202 may be configured to determine that the electrical current reading is low and/or high based on current criteria, and control a movement of theguard108 to move theguard108 toward (if low) or away (if high) from the cutting finished position.
• Theprocessor202 may assess the electrical current reading against the current criteria in real time (e.g., at least once every second, such as 1-1,000,000 times per second) and direct theguard actuator140 as indicated. The current criteria (e.g., predetermined upper and lower threshold values) may be stored in thememory204. In some embodiments, theguard actuator140 can control a movement of theguard108 between at least the cutting start position and the cutting finished position, andprocessor202 may assess the electrical current reading against the current criteria only when theguard108 is positioned between the cutting start position and the cutting finished position. For example, theprocessor202 may not automatically direct the position ofguard108 when theguard108 is in a guard insertion position (e.g., opened farther than the cutting start position to facilitate insertion of the guard between the ring and appendage) (e.g., seeFIG.6A).
• In some embodiments (and not others), thering cutter100 may include a cuttingprogress indicator218. The cuttingprogress indicator218 provides a visual indication to the operator and/or patient of how much ring remains to be cut. The cuttingprogress indicator218 may provide any visual indication indicative of the remaining ring to cut. For example, the cuttingprogress indicator218 may be implemented as an analog (e.g., a needle gage or sliding gage) or digital (e.g., light strip or LCD display) device. The remaining ring to be cut may be determined based on the position ofguard108 relative to its fully closed position (e.g., cutting finished position).
• The cuttingprogress indicator218 may receive the position ofguard108 in a mechanical or electrical manner. For example, an analog progress indicator may be mechanically connected to theguard108 or to theguard actuator140, and translate that position to a visual medium (e.g., a rotating needle or sliding indicator). In other examples, adigital progress indicator218 may be directed by theprocessor202, which receives electronic position information associated with theguard108 from theposition sensor214. Theprocessor202 may be configured to receive, from theposition sensor214, a position signal associated with theguard108, and direct the cuttingprogress indicator218 to update based on the position signal.
• In the illustrated embodiment, the cuttingprogress indicator218 is digital and configured in the shape of an arc218 (FIG.2D). The degree to whicharc218 is colored or illuminated may convey to the operator or patient the amount of cutting that remains. When the arc is fully illuminated or colored (closed) the cut is complete (or it may be configured in reverse). In other embodiments, a digitalcutting progress indicator218 may be implemented as a string of discrete lights that are illuminated (or darkened) as the cutting progresses. In other embodiments, the cuttingprogress indicator218 may be implemented using a series of discrete multi-coloured lights that change colour as the cutting progresses (e.g., green is the amount the ring that has been cut while blue is the amount of ring remaining to be cut).
• The cuttingprogress indicator218 may also provide a visual indication of the rate at which the ring is being cut and the remaining cut time. For example, if the cuttingprogress indicator218 is static for a prolonged period, this would indicate to the operator that the ring cutting is not progressing.
• The cuttingprogress indicator218 may be positioned anywhere on thering cutter100. For example, the cuttingprogress indicator218 may be located at the front end where it may be visible primary to the patient, on a side face where it may be visible to both the patient and operator, or a rear face (as shown inFIG.2D) where it may be visible primarily to the operator. In the illustrated embodiment, theblade106 is located at thefront end110 of thering cutter100 and the cuttingprogress indicator218 is located at therear end112 of thering cutter100. Such an arrangement can make it easier for the operator to view the cuttingprogress indicator218 during the cutting process and to react if the cutting is not progressing as expected.
• In addition to or as an alternative to adjustments to theguard108 based on motor current readings, theelectronic control system200 may adjust the speed of the blade motor104 (and thereby the speed of blade106) in response to temperature readings associated with theguard108. Theelectronic control system200 may store (e.g., in the memory204) a threshold temperature that is safe for the patient. Above the threshold temperature, there is an increased risk of burning the appendage due to the heat generated by the cutting. By monitoring a temperature associated with theguard108, theelectronic control system200 may set theblade motor104 to the highest speed with a view to reducing the speed anytime the sensed temperature exceeds the predetermined temperature threshold. Compared to a system that does not monitor temperature, this avoids having to (a) rely on complaints of burning from the patient to determine that the speed should be decreased or (b) keep speeds relatively low to avoid any possibility of burning the patient. All things being equal, this should increase the cutting speed and reduce the time required to cut a trapped ring off an appendage.
• In some embodiments, theprocessor202 may be configured to receive, from the temperature sensor216, a temperature reading associated with theguard108, and direct a speed of theblade motor104 based at least in part on the temperature reading. For example, theprocessor202 may be configured to decrease the speed of theblade motor104 in response to determining that the temperature reading exceeds a predetermined upper threshold value. Alternatively, or in addition, theprocessor202 may be configured to decrease the speed of theblade motor104 in response to determining that the change in temperature readings is trending towards a temperature that exceeds the predetermined upper threshold value. In some examples, theprocessor202 may be configured to increase the speed ofblade motor104 in response to determining that the temperature reading (or change in temperature reading) is (or is trending towards) a value that falls below a predetermined lower threshold value.
• Alternatively, or in addition to changing the speed ofblade motor104 based at least in part on temperature readings, the electronic control system200 (e.g., the processor202) may be configured to control the movement (e.g., movement speed) of theguard108 based at least in part on the temperature reading. For example, theprocessor202 may be configured to direct theguard actuator140 to increase the movement speed of theguard108 toward theperipheral cutting edge120 in response to determining that the temperature reading is below a predetermined lower threshold value. Alternatively, or in addition, theprocessor202 may be configured to direct theguard actuator140 to decrease the movement speed of theguard108 toward theperipheral cutting edge120 in response to determining that the temperature reading exceeds a predetermined upper threshold value.
• Theprocessor202 may assess the temperature readings against the temperature criteria (e.g., value exceeds or falls below an upper or lower threshold value, or rate of change in value is trending towards a value above or below an upper or lower threshold value) in real time (e.g., at least once every second, such as 1-1,000,000 times per second) and direct theblade motor104 and/or theguard actuator140 as indicated. The temperature criteria (e.g., the predetermined upper and lower threshold values) may be stored in thememory204.
• In some embodiments (and not others), thering cutter100 may include alubrication indicator228. Thelubrication indicator228 can provide a visual and/or audible alert or reminder to the operator to apply a lubricant. The application of a lubricant (or coolant) during the cutting operation may reduce cut time, cutting temperature, or both. Lubricant can be applied on the inside face of theblade106, the outside face of theblade106, the ring, or a combination thereof. Lubricant can be applied with an external dispensing vessel. Alternatively, thering cutter100 may have an onboard lubrication reservoir (not shown) for holding and dispensing lubricant or coolant.
• Thelubrication indicator228 may provide any visual or audible alert to the operator that lubricant or coolant should be applied. For example, thelubrication indicator218 may be implemented as a speaker that emits an audible sound to notify the operator that lubricant should be added (e.g., a “beeping” noise). Alternatively, thelubrication indicator228 may be a light strip or an LCD display. In the illustrated embodiment, thelubrication indicator228 is digital and implemented as an LED228 (seeFIG.2D). In this embodiment, theLED228 may flash when lubricant or coolant should be applied. Alternatively, theLED228 may change colours when lubricant or coolant should be applied.
• Thelubrication indicator228 may be directed by theprocessor202, which may be configured to track cutting time. For example, theprocessor202 may track cutting time starting from the activation of theblade motor204. Theprocessor202 may direct thelubrication indicator228 to issue an alert at a regular interval throughout the cutting process (e.g., beep every 3 minutes, start flashing every 4 minutes, etc.).
• Alternatively, or in addition, theprocessor202 may direct thelubrication indicator228 based on cutting progress (e.g., apply lubricant at25, 50% and 75% completion). As described above, to determine cutting progress, theprocessor202 may receive electronic position information associated with theguard108 from theposition sensor214. Theprocessor202 may be configured to receive, from theposition sensor214, a position signal associated with theguard108, and direct thelubrication indicator228 to operate based on the position signal.
• Alternatively, or in addition, theprocessor202 may direct thelubrication indicator228 based on guard temperature. As described above, theprocessor202 may receive temperature readings associated with theguard108 from the temperature sensor216. Theprocessor202 may be configured to receive, from thetemperature sensor214, a temperature signal associated with theguard108, and direct thelubrication indicator228 to operate (e.g., beep if a speaker, flash if a light) based on the temperature signal. For example, theprocessor202 may be configured to direct thelubrication indicator228 to operate in response to determining that the temperature reading is above a predetermined upper threshold value. The application of lubricant or coolant may lower the temperature.
• Thelubrication indicator228 may be positioned anywhere on thering cutter100. For example, thelubrication indicator228 may be located on a side face where it may be visible to both the patient and operator, or a rear face (as shown inFIG.2D) where it may be visible primarily to the operator. In the illustrated embodiment, theblade106 is located at thefront end110 of thering cutter100 and thelubrication indicator218 is located at therear end112 of thering cutter100. Such an arrangement can make it easier for the operator to view or hear thelubrication indicator218 during the cutting process.
• FIG.8 shows a ring cutter, referred to generally as100′, in accordance with an alternative embodiment. Thering cutter100′ shown inFIG.8 is similar to thering cutter100 ofFIGS.2A-2D. Elements having similar structure and/or performing similar function as those in thering cutter100 ofFIGS.2A-2D are similarly numbered. Differences between thering cutter100′ and thering cutter100 are described below.
• Referring toFIG.8, thebody102 extends from a body nose end220 to a bodyrear end222 along a body axis224. As shown, thebody102 tapers from the bodyrear end222 toward the body nose end220. Theblade106 is positioned proximate the body nose end220. This configuration keeps thering cutter100′ compact in the region surrounding theblade106 and may provide it easier access to rings in tight spaces.
• Thehandle178 is located at therear end112 of thering cutter100′. The handleupper end182 is mounted to the bodyrear end222. As shown, thehandle178 extends downwardly and rearwardly from the handleupper end182 at an angle of about 40° relative to the body axis224. In alternative embodiments, the angle may be higher (e.g., between 40 and 60°) or less (e.g., between 20 and 40°). Orienting thehandle178 so that thehandle axis180 extends at an angle between 20 and 60° relative to the body axis224 may improve the ergonomics of thering cutter100′.
• FIG.9 shows a ring cutter, referred to generally as100″, in accordance with another alternative embodiment. Thering cutter100″ shown inFIG.9 is similar to thering cutter100 ofFIGS.2A-2D. Elements having similar structure and/or performing similar function as those in thering cutter100 ofFIGS.2A-2D are similarly numbered. Differences between thering cutter100″ and thering cutter100 are described below.
• Referring toFIG.9, thebody102 is configured as a block that is designed to sit on a support surface226 (e.g., a workbench, counter, etc.). Accordingly, thesupport surface226 may bear the full weight of thering cutter100″. In some cases, thering cutter100″ may be operated by the individual who has the ring trapped on one of their appendages. That is, there may be no need of a second individual to operator thering cutter100″. This may be convenient in an emergency when no one else is available to operate thering cutter100″.
• As described above, lateral movement of theguard108 relative to thering10 and thefinger20 during a cutting process can cause bruising and discomfort to the patient. The block configuration of thebody102 may provide thering cutter100″ with enhanced stability (e.g., due to the extent of its surface-to-surface contact with the support surface226). In some cases, thebody102 may be weighted to avoid it from moving relative to the support surface226 (e.g., slipping) during the cutting process. Thering cutter100″ has no need for a handle, although one may be provided in alternative embodiments to make it easier to adjust the position of thering cutter100″.
• FIG.10 shows a schematic illustration of a kit400. As shown, the kit400 includes thering cutter100 ofFIGS.2A-2D and acompression device402 for freeing a ring trapped on an appendage. In an alternative embodiment, thering cutter100 in kit400 may be replaced with thering cutter100′ ofFIG.8 or thering cutter100″ ofFIG.9. Thecompression device402 may be any one of the compression devices disclosed in U.S. Pat. No. 10,702,282, which is incorporated herein by reference in its entirety, except for any definitions, subject matter disclaimers or disavowals, and except to the extent that the incorporated material is inconsistent with the express disclosure herein, in which case the language in this disclosure controls.
• Thecompression device402 is designed to non-destructively remove a trapped ring from an appendage. That is, thecompression device402 can be used to remove the ring from the appendage without causing any permanent damage, change and/or transformation to the ring. On the other hand, thering cutter100 is designed to transect a ring trapped on an appendage. In this way, the kit400 provides both a nondestructive means (i.e.., the compression device402) and a destructive method means (e.g., the ring cutter100) to remove rings trapped on appendages. With the kit400, the operator may first elect to use thecompression device402 to free a trapped ring without damaging it. If this proves unsuccessful, the operator may then use thering cutter100 to transect the trapped ring (i.e., cut it off).
• As used herein, the wording “and/or” is intended to represent an inclusive - or. That is, “X and/or Y” is intended to mean X or Y or both, for example. As a further example, “X, Y, and/or Z” is intended to mean X or Y or Z or any combination thereof.
• While the above description describes features of example embodiments, it will be appreciated that some features and/or functions of the described embodiments are susceptible to modification without departing from the spirit and principles of operation of the described embodiments. For example, the various characteristics which are described by means of the represented embodiments or examples may be selectively combined with each other. Accordingly, what has been described above is intended to be illustrative of the claimed concept and non-limiting. It will be understood by persons skilled in the art that other variants and modifications may be made without departing from the scope of the invention as defined in the claims appended hereto. The scope of the claims should not be limited by the preferred embodiments and examples, but should be given the broadest interpretation consistent with the description as a whole.
Items
• Item 1. A ring cutter for safely transecting a ring trapped on an appendage, the ring cutter comprising:
• a body;
• a blade motor housed in the body;
• a circular blade drivingly connected to the blade motor, the blade having a blade rotation axis and a peripheral cutting edge;
• a guard coupled to the body and insertable between the ring and the appendage to position the ring between the guard and the blade;
• a guard actuator drivingly connected to the guard and controlling a movement of the guard;
• a current sensor positioned to sense electrical current associated with the blade motor; and
• one or more processors communicatively coupled to the current sensor and the guard actuator, wherein the one or more processors are configured to collectively:
  • receive, from the current sensor, an electrical current reading associated with the blade motor; and
  • transmit, to the guard actuator, one or more commands to control the movement of the guard based at least on the electrical current reading.
• Item 2. A ring cutter for safely transecting a ring trapped on an appendage, the ring cutter comprising:
• a body;
• a blade motor housed in the body;
• a circular blade drivingly connected to the blade motor, the blade having a blade rotation axis and a peripheral cutting edge;
• a guard coupled to the body and insertable between the ring and the appendage to position the ring between the guard and the blade;
• a guard actuator drivingly connected to the guard and controlling a movement of the guard between at least a cutting start position and a cutting finished position;
• a position sensor located to sense a position associated with the guard;
• a cutting progress indicator associated with the movement of the guard between the cutting start and cutting finished positions; and
• one or more processors communicatively coupled to the position sensor and the cutting progress indicator, wherein the one or more processors are configured to collectively:
  • receive, from the position sensor, a position signal associated with the guard; and
  • direct the cutting progress indicator to update based on the position signal.
• Item 3. A ring cutter for safely transecting a ring trapped on an appendage, the ring cutter comprising:
• a body;
• a blade motor housed in the body;
• a circular blade drivingly connected to the blade motor, the blade having a blade rotation axis and a peripheral cutting edge;
• a guard coupled to the body and insertable between the ring and the appendage to position the ring between the guard and the blade;
• a temperature sensor positioned to sense a temperature associated with the guard; and
• one or more processors communicatively coupled to the temperature sensor and the blade motor, wherein the one or more processors are configured to collectively:
  • receive, from the temperature sensor, a temperature reading associated with the guard; and
  • direct a speed of the blade motor based at least in part on the temperature reading.
• Item 4. A ring cutter for safely transecting a ring trapped on an appendage, the ring cutter comprising:
• a body;
• a blade motor housed in the body;
• a circular blade drivingly connected to the blade motor, the blade having a blade rotation axis and a peripheral cutting edge;
• a guard coupled to the body and insertable between the ring and the appendage to position the ring between the guard and the blade;
• a guard actuator drivingly connected to the guard and controlling a movement of the guard;
• a temperature sensor positioned to sense a temperature associated with the guard; and
• one or more processors communicatively coupled to the temperature sensor and the guard actuator, wherein the one or more processors are configured to collectively:
  • receive, from the temperature sensor, a temperature reading associated with the guard; and
  • transmit, to the guard actuator, one or more commands to control the movement of the guard based at least in part on the temperature reading.
• Item 5. The ring cutter of any preceding item, wherein said controlling the movement of the guard comprises controlling a movement speed of the guard toward the peripheral cutting edge, and the one or more processors are further configured to collectively:
• in response to determining that the electrical current reading is below a predetermined lower threshold value, direct the guard actuator to increase the movement speed of the guard toward the peripheral cutting edge.
• Item 6. The ring cutter of any preceding item, wherein the one or more processors are further configured to collectively:
• in response to determining that the electrical current reading exceeds a predetermined upper threshold value, direct the guard actuator to decrease the movement speed of the guard toward the peripheral cutting edge.
• Item 7. The ring cutter of any preceding item, wherein the guard has a guard proximal end pivotably connected to the body at a guard pivot axis, and a guard distal end spaced apart from the guard proximal end, the guard distal end being insertable between the ring and the appendage to position the ring between the guard and the blade.
• Item 8. The ring cutter of any preceding item, wherein the blade motor has a motor rotation axis that extends longitudinally, and the guard pivot axis extends laterally.
• Item 9. The ring cutter of any preceding item, wherein said controlling the movement of the guard comprises controlling a pivoting of the guard about the guard pivot axis.
• Item 10. The ring cutter of any preceding item, wherein the guard is pivotable about the guard pivot axis in:
• a guard closing direction, which moves the guard distal end toward the peripheral cutting edge, and
• a guard opening direction, which moves the guard distal end away from the peripheral cutting edge.
• Item 11. The ring cutter of any preceding item, wherein the one or more processors are further configured to collectively:
• in response to determining that the electrical current reading is below a predetermined lower threshold value, direct the guard actuator to pivot the guard about the guard pivot axis in the guard closing direction.
• Item 12. The ring cutter of any preceding item, wherein the guard is pivotable about the guard pivot axis between at least:
• a cutting start position; and
• a cutting finished position, in which the guard distal end is closer to the peripheral cutting edge than in the cutting start position.
• Item 13. The ring cutter of any preceding item, wherein the one or more processors are further configured to collectively:
• in response to determining that the electrical current reading is below a predetermined lower threshold value, direct the guard actuator to pivot the guard about the guard pivot axis toward the cutting finished position.
• Item 14. The ring cutter of any preceding item, wherein the guard is inhibited from pivoting toward the peripheral cutting edge when in the cutting finished position.
• Item 15. The ring cutter of any preceding item, wherein the guard is pivotable about the guard pivot axis to a guard insertion position, in which the guard distal end is spaced farther apart from the peripheral cutting edge than in the cutting start position.
• Item 16. The ring cutter of any preceding item, wherein the cutting start position is intermediate of the cutting finished position and the guard insertion position.
• Item 17. The ring cutter of any preceding item, further comprising a user-operable guard adjustment input communicatively coupled to at least one of the processors, and the one or more processors are further configured to collectively:
• direct the guard actuator to pivot the guard about the guard pivot axis between the guard insertion position and the cutting start position in response to user interaction with the guard adjustment input.
• Item 18. The ring cutter of any preceding item, wherein the one or more processors are configured to collectively:
• perform said receiving and transmitting when the guard is between the cutting start position and the cutting finished position.
• Item 19. The ring cutter of any preceding item, further comprising an energy storage member electrically coupled to the blade motor to power the blade motor.
• Item 20. The ring cutter of any preceding item, further comprising a pistol grip handle provided at a rear end of the ring cutter.
• Item 21. The ring cutter of any preceding item, wherein the pistol grip handle has an upper end that is mounted to the body.
• Item 22. The ring cutter of any preceding item, wherein, when the ring cutter is oriented with an upper end of the ring cutter positioned above a lower end of the ring cutter, the body has a body upper surface and a body lower surface, and the upper end of the pistol grip handle is mounted to the body lower surface.
• Item 23. The ring cutter of any preceding item, further comprising a resting base provided at a lower end of the pistol grip handle, the support base extending outboard of the lower end of the pistol grip handle, the resting base being engageable with a ring cutter support surface.
• Item 24. The ring cutter of any preceding item, further comprising an energy storage member electrically coupled to the blade motor to power the blade motor, the energy storage member being positioned at a lower end of the pistol grip handle.
• Item 25. The ring cutter of any preceding item, wherein the energy storage member is housed in the resting base.
• Item 26. The ring cutter of any preceding item, further comprising a user-operable motor activation switch communicatively coupled to at least one of the processors, and the one or more processors are further configured to collectively:
• activate the blade motor in response to user interaction with the motor activation switch.
• Item 27. The ring cutter of any preceding item, wherein the motor activation switch is provided proximate the upper end of the pistol grip handle.
• Item 28. The ring cutter of any preceding item, wherein the blade motor has a motor rotation axis that extends transverse to the blade rotation axis.
• Item 29. The ring cutter of any preceding item, wherein the blade motor has a motor rotation axis that extends longitudinally, and the blade rotation axis extends laterally.
• Item 30. The ring cutter of any preceding item, wherein the guard includes a guard distal segment that has the guard distal end, and the guard distal segment including a ring abutment ledge and a curved ring lever extending distally from the ring abutment ledge, the curved ring lever being insertable between the ring and the appendage to position the ring against the ring abutment ledge.
• Item 31. The ring cutter of any preceding item, wherein the blade is removably connected to a drive shaft of the blade motor.
• Item 32. The ring cutter of any preceding item, wherein the position sensor is located to sense a position of the guard actuator, and the one or more processors are further configured to collectively:
• associate the position of the guard actuator with a position of the guard.
• Item 33. The ring cutter of any preceding item, wherein the guard actuator is a linear actuator, and the position sensor is a linear sensor.
• Item 34. The ring cutter of any preceding item, wherein the guard actuator is a rotary actuator, and the position sensor is a rotation sensor.
• Item 35. The ring cutter of any preceding item, wherein the blade is located at a front end of the ring cutter and the cutting progress indicator is located at a rear end of the ring cutter.
• Item 36. The ring cutter of any preceding item, wherein the one or more processors are further configured to collectively:
• decrease the speed of the blade motor in response to determining that the temperature reading exceeds an upper threshold value.
• Item 37. The ring cutter of any preceding item, wherein the temperature sensor is positioned on the guard.
• Item 38. The ring cutter of any preceding item, wherein said controlling the movement of the guard comprises controlling a movement speed of the guard toward the peripheral cutting edge, and the one or more processors are further configured to collectively:
• in response to determining that the temperature reading is below a predetermined lower threshold value, direct the guard actuator to increase the movement speed of the guard toward the peripheral cutting edge.
• Item 39. The ring cutter of any preceding item, wherein the one or more processors are further configured to collectively:
• in response to determining that the temperature reading exceeds a predetermined upper threshold value, direct the guard actuator to decrease the movement speed of the guard toward the peripheral cutting edge.
• Item 40. A kit comprising:
• the ring cutter of any preceding item, and
• a compression device for freeing the ring trapped on the appendage, the compression device comprising:
  • an outer body extending from a body proximal end to a body distal end, the outer body comprising:
    • a digit cavity extending from a cavity proximal opening at the body proximal end, and
    • a fluid inlet; and
  • a removable bladder including a bladder intermediate portion joining a bladder proximal portion to a bladder distal portion, the bladder intermediate portion located inside the digit cavity,
  • wherein the removable bladder and the outer body together define an inflation chamber inside the digit cavity, and the fluid inlet is fluidly connected to the inflation chamber.

Claims (21)

1. A ring cutter for safely transecting a ring trapped on an appendage, the ring cutter comprising:

a body;

a blade motor housed in the body;

a circular blade drivingly connected to the blade motor, the blade having a blade rotation axis and a peripheral cutting edge;

a guard coupled to the body and insertable between the ring and the appendage to position the ring between the guard and the blade;

a guard actuator drivingly connected to the guard and controlling a movement of the guard;

a current sensor positioned to sense electrical current associated with the blade motor; and

one or more processors communicatively coupled to the current sensor and the guard actuator, wherein the one or more processors are configured to collectively:

receive, from the current sensor, an electrical current reading associated with the blade motor; and

transmit, to the guard actuator, one or more commands to control the movement of the guard based at least on the electrical current reading.

2. The ring cutter ofclaim 1, wherein said controlling the movement of the guard comprises controlling a movement speed of the guard toward the peripheral cutting edge, and the one or more processors are further configured to collectively:

in response to determining that the electrical current reading is below a predetermined lower threshold value, direct the guard actuator to increase the movement speed of the guard toward the peripheral cutting edge.

3. The ring cutter ofclaim 2, wherein the one or more processors are further configured to collectively:

in response to determining that the electrical current reading exceeds a predetermined upper threshold value, direct the guard actuator to decrease the movement speed of the guard toward the peripheral cutting edge.

4. The ring cutter ofclaim 1, wherein the guard has a guard proximal end pivotably connected to the body at a guard pivot axis, and a guard distal end spaced apart from the guard proximal end, the guard distal end being insertable between the ring and the appendage to position the ring between the guard and the blade.

5. The ring cutter ofclaim 4, wherein the blade motor has a motor rotation axis that extends longitudinally, and the guard pivot axis extends laterally.

6. The ring cutter ofclaim 4, wherein said controlling the movement of the guard comprises controlling a pivoting of the guard about the guard pivot axis.

7. The ring cutter ofclaim 6, wherein the guard is pivotable about the guard pivot axis in:

a guard closing direction, which moves the guard distal end toward the peripheral cutting edge, and

a guard opening direction, which moves the guard distal end away from the peripheral cutting edge.

8. The ring cutter ofclaim 7, wherein the one or more processors are further configured to collectively:

in response to determining that the electrical current reading is below a predetermined lower threshold value, direct the guard actuator to pivot the guard about the guard pivot axis in the guard closing direction.

9. The ring cutter ofclaim 6, wherein the guard is pivotable about the guard pivot axis between at least:

a cutting start position, and

a cutting finished position, in which the guard distal end is closer to the peripheral cutting edge than in the cutting start position.

10. The ring cutter ofclaim 9, wherein the one or more processors are further configured to collectively:

in response to determining that the electrical current reading is below a predetermined lower threshold value, direct the guard actuator to pivot the guard about the guard pivot axis toward the cutting finished position.

11. The ring cutter ofclaim 9, wherein the guard is inhibited from pivoting toward the peripheral cutting edge when in the cutting finished position.

12. The ring cutter ofclaim 9, wherein the guard is pivotable about the guard pivot axis to a guard insertion position, in which the guard distal end is spaced farther apart from the peripheral cutting edge than in the cutting start position.

13. The ring cutter ofclaim 12, further comprising a user-operable guard adjustment input communicatively coupled to at least one of the processors, and the one or more processors are further configured to collectively:

direct the guard actuator to pivot the guard about the guard pivot axis between the guard insertion position and the cutting start position in response to user interaction with the guard adjustment input.

14. The ring cutter ofclaim 9, wherein the one or more processors are configured to collectively:

perform said receiving and transmitting when the guard is between the cutting start position and the cutting finished position.

15. The ring cutter ofclaim 4, wherein the guard includes a guard distal segment that has the guard distal end, the guard distal segment including a ring abutment ledge and a curved ring lever extending distally from the ring abutment ledge, the curved ring lever being insertable between the ring and the appendage to position the ring against the ring abutment ledge.

16-20. (canceled)

21. The ring cutter ofclaim 1, further comprising an energy storage member electrically coupled to the blade motor to power the blade motor.

22. The ring cutter ofclaim 1, further comprising a pistol grip handle provided at a rear end of the ring cutter.

23. The ring cutter ofclaim 22, wherein the pistol grip handle has an upper end that is mounted to the body.

24. The ring cutter ofclaim 23, wherein, when the ring cutter is oriented with an upper end of the ring cutter positioned above a lower end of the ring cutter, the body has a body upper surface and a body lower surface, and the upper end of the pistol grip handle is mounted to the body lower surface.

25. The ring cutter ofclaim 22, further comprising a resting base provided at a lower end of the pistol grip handle, the resting base extending outboard of the lower end of the pistol grip handle, the resting base being engageable with a ring cutter support surface.

Images