Detailed Description
Examples of disclosed delivery systems for dispensing a biologically active substance to a patient and related methods of use are discussed in terms of a drug delivery pen for dispensing a biologically active substance to a patient, and more particularly in terms of an injection device comprising components for setting and delivering one or more selected doses from a drug cartridge. In some examples, the present delivery systems and methods are used to administer one or more drugs, e.g., insulin. In some examples, the present delivery system includes a drug delivery pen having components configured to provide audible and/or tactile feedback associated with dose setting, dose correction, and/or dose delivery. In some examples, the drug delivery pen has a component configured to provide audible and/or tactile feedback, including indicia, such as a click generated by at least one component having one or more teeth. In some examples, the drug delivery pen includes one or more ratchet components that generate a torque for driving movement, the torque corresponding to a force directly associated with audible and/or tactile feedback. In some examples, the ratchet component includes one or more arm configurations that provide uniform audible and/or tactile feedback. In some examples, one or more components of the present delivery system may be reusable or disposable.
In some examples, the present delivery system includes a drug delivery pen having a first ratchet, a second ratchet, and a drive ratchet, e.g., a check ratchet. In some examples, a non-return ratchet is disposed between the drive member and the nut member. In some examples, the first ratchet defines a smaller circumference relative to the second ratchet. In some examples, one or more of the ratchets has one or more arms located on a component having a first ratchet section and a second ratchet section, e.g., a stepped ratchet and/or a dual ratchet. In some examples, the first ratchet interacts with a drive component (e.g., a threaded sleeve) and the second ratchet interacts with a dose setting and/or dial component (e.g., a dose sleeve). In some examples, the second ratchet provides tactile feedback while increasing the selected dose setting. In some examples, the first ratchet provides tactile feedback while less of the selected dose is set.
In some examples, the present delivery system includes a drug delivery pen having a non-return ratchet that prevents one or more components from back-driving due to back pressure from the drug cartridge and/or prevents a user from winding a piston rod (e.g., a lead screw) back into the housing of the drug delivery pen to avoid moving the lead screw and/or a bearing connected to the lead screw away from the plunger and/or cartridge stop. In some examples, the non-return ratchet controls incremental rotational stepping movement of the lead screw as the lead screw rotates to control rotational accuracy of the drug delivery pen. In some examples, when the user decreases the dose setting, the non-return ratchet resists the torque applied from the first ratchet to avoid pressurizing the cartridge when the user attempts to decrease the selected dose.
In some examples, the present delivery system includes a drug delivery pen having one or more ratchets, including a ratchet profile that provides a selected torque profile, as described herein. In some examples, the ratchet profile includes a selected tooth profile. In some examples, the ratchet includes a tooth profile having an initial position and/or start of the ratchet. In some examples, the ratchet includes a tooth profile that provides torque to initiate rotation of the ratchet and resistance of the ratchet to back drive. In some examples, the ratchet includes a gear profile having a continuous curve that provides a sharp torque at the beginning of movement and a decrease in the rate of torque increase as the movement of the ratchet increases. In some examples, the ratchet includes a tooth profile having a torque gradient that decreases linearly by movement of the ratchet. In some examples, the ratchet includes a gear profile having a continuous radius that prevents abrupt torque changes. In some examples, the ratchet has a gear profile that includes teeth points and/or lands with a flat or planar surface. In some examples, the tooth top is disposed adjacent to a middle portion of the tooth profile. In some examples, the gear profile transitions from the tooth top to an adjacent tooth profile along the dip. In some examples, the gear profile includes a continuous curve that matches the selected torque at the initiation of the ratchet motion such that the rate of torque increase decreases with increasing ratchet movement. In some examples, the gear profile includes a gradient that decreases linearly by ratchet movement.
In some examples, the present delivery system includes a drug delivery pen having one or more ratchets including an arm arrangement. In some examples, an arm arrangement provides audible feedback, such as a click without excessive force application. In some examples, an arm arrangement includes bearing surfaces on opposite sides of the tooth profile to maintain ratchet position and/or orientation, e.g., center. In some examples, the drug delivery pen has one or more ratchets comprising a two-arm arrangement. In some examples, the two arms are arranged to provide increased rigidity and/or stiffness for drug delivery pen operation. In some examples, the drug delivery pen has one or more ratchets comprising a three-arm arrangement including an even number of positions and an odd number of arms/teeth, the odd number of arms/teeth being self-positioning.
In some examples, the present delivery system includes a drug delivery pen having a driver including a single-tooth ratchet. In some examples, the driver includes a three-tooth ratchet that provides uniform audible and/or tactile feedback and/or balancing to the drug delivery pen operation to resist and/or prevent, for example, unsynchronized audible and/or tactile feedback.
In some examples, the present delivery system includes a drug delivery pen having a driver that includes a check drive sleeve that includes a single-arm or single-leg tooth ratchet. In some examples, the driver includes a check drive sleeve with a three-armed or three-legged toothed ratchet. In some examples, the driver includes a dual ratchet having a first side with a single arm or leg having teeth and a second side with a single arm or leg having teeth. In some examples, the arms or legs are disposed in a circumferential configuration. In some examples, the first arm or leg has a greater circumference than the second arm or leg. In some examples, the dual ratchet includes a bearing surface configured to react to a force applied to the dual ratchet (e.g., a force on opposite sides of a tooth profile). In some examples, the ratchet includes a first ratchet arm tooth that resists an upward dial rotation that would cause a second ratchet arm tooth to rattle over the ratchet feature such that downward dial-down does not cause rotation of the check drive sleeve. In some examples, the ratchet includes large diameter ratchet teeth that prevent rotation of the dual ratchet during downward dialing, which would cause the small diameter ratchet arm to rattle/deflect over the ratchet feature when the dose sleeve is rotated to select a lower dose.
In some examples, the present delivery system includes a drug delivery pen having one or more drive components with a low torque configuration. In some examples, the present delivery system includes a drug delivery pen having a lead screw and a check drive sleeve that provide a range of about 80% to 90% of the total torque for moving the lead screw. In some examples, the present delivery system includes a drug delivery pen having a nut and a check drive sleeve including a tooth form and a nut profile that maintain ratchet resistance to movement and reduce peak torque by about 90% of the total torque for moving the lead screw. In some examples, the nut and the check drive sleeve include a smooth transition between different torques.
In some examples, the present delivery system includes a drug delivery pen having a dose setting member including a housing thread form and a dose sleeve thread form having an axial clearance in the range of about 0.10 millimeters (mm) to 0.50 mm. In some examples, the present delivery system includes a drug delivery pen having a dose setting member comprising a housing thread form and a dose sleeve thread form having a radial clearance in the range of about 0.05mm to 0.25 mm. In some examples, the present delivery system includes a drug delivery pen having a dose setting member comprising a housing thread form and a dose sleeve thread form having an axial clearance of about 0.30mm and/or a radial clearance of 0.15 mm. In some examples, the dose setting member comprises a housing thread form and a dose sleeve thread form with an axial clearance of 0.2 mm.
In some examples, the present delivery system includes a drug delivery pen having a zero dose stop with an overshoot tolerance of about +/-7 degrees at a zero dose stop position.
In some examples, the present delivery system includes a drug delivery pen having a cap that provides one or more of a UV blocker, a pocket clip, a needle protector for storage, a cartridge protector that absorbs shock during drop, a cartridge holder attachable in any orientation, cap rotation limiting or stopping until torque limiting, providing visual indicia of the drug container and/or cartridge contents, providing visual indicia of the plunger, attachment and detachment of the pen needle, access of the needle cannula and/or cartridge septum, drive and/or housing support, axial force transfer of the piston rod to the cartridge plunger, torque transfer limiting of the cartridge plunger, point load distribution from the piston rod to the cartridge plunger surface, an auxiliary assembly, providing visual indicia of a selected dose, zero dose stop, and/or non-locking threaded engagement with the housing.
In some examples, the present delivery system includes a drug delivery pen having a piston rod that provides one or more of the features that large diameter ratchet teeth prevent rotation of the dual ratchet during dial down from causing the small diameter ratchet arm to rattle/deflect over the ratchet, and/or visual indicia of proper use. In some examples, the present delivery system includes a drug delivery pen having a housing that provides one or more of the following features of a visual marking of the label and dial member, an unlocked threaded engagement with the dial member, an axial restraint of the nut, a threaded engagement with the piston rod, and/or a ratcheting engagement with the driver (e.g., a check drive sleeve).
In some examples, the present delivery system includes a drug delivery pen having a driver, such as a threaded sleeve, that provides one or more of the following features of placing the last dose nut in the correct orientation during assembly, threadingly engaging the last dose nut, axial ratchet features that allow rotation relative to a dial component (e.g., a dose sleeve during dialing and dose delivery), and/or small diameter ratchet teeth that resist dial-up rotation causing the upper ratchet arm to rattle over a large diameter ratchet in the dose sleeve.
In some examples, the present delivery system includes a drug delivery pen having a last dose nut that provides one or more of the features of preventing dialing of a dose greater than an amount of insulin deliverable from a cartridge, rotationally keyed to a dial component (e.g., a dose sleeve) and axially free to move along a pen axis, and/or facilitating assembly.
In some examples, the present delivery system includes a drug delivery pen having a dual ratchet that provides one or more of the features of small diameter ratchet arm teeth that resist dial-up rotation causing the upper ratchet arm to rattle over the ratchet feature, large diameter ratchet teeth that prevent rotation of the dual ratchet during dial-down causing the small diameter ratchet arm to rattle/deflect over the ratchet feature when the dial-up component (e.g., dose sleeve rotate to select a lower dose) allows the driver (e.g., threaded sleeve) to move in a small axial direction during dial-down, transmitting axial force from the dose button to the dose sleeve, and/or limiting axial travel of the threaded sleeve.
In some examples, the present delivery system includes a drug delivery pen for use with a method for dispensing a medicament to a patient, the method including the steps of dialing and/or cancelling a dose. In some examples, the step of dialing and/or cancelling the dose includes rotating the dose sleeve clockwise such that the dose sleeve extends out of the housing. In some examples, the step of dialing and/or cancelling the dose includes generating a dose increment click using a topmost pawl of a dual ratchet clicker that clicks over teeth in a dose sleeve. In some examples, dialing and/or cancelling a dose prevents rotation of the lead screw and the check drive sleeve, which is prevented by a ratchet between the check drive sleeve and the threaded nut. In some examples, the step of dialing and/or cancelling the dose includes selecting a maximum dose indicated by a maximum extension of the check drive sleeve away from the threaded sleeve. In some examples, the step of dialing and/or canceling the dose includes rotating the dose sleeve counter-clockwise and canceling the selected dose. In some examples, the step of dialing and/or cancelling the dose includes rotating the dual ratchet clicker with the dose sleeve such that the lower pawl clicks over the teeth of the threaded sleeve. In some examples, the step of dialing and/or cancelling the dose includes preventing rotation of the lead screw, as the pawl at one end of the non-return drive sleeve is more rigid and/or stiffer than the pawl on the dual ratchet clicker, so the ratchet between the dual ratchet clicker and the threaded sleeve may rotate relatively. In some examples, the step of dialing and/or cancelling the dose includes a last dose nut that advances the threaded sleeve up and down when dialing and/or cancelling the dose.
In some examples, the present delivery system includes a drug delivery pen for use with a method for dispensing a medicament to a patient, the method including the step of delivering a dose. In some examples, the step of delivering the dose includes engaging teeth of the dose sleeve with teeth of the threaded sleeve to lock the sleeves together. In some examples, the step of delivering the dose includes driving the dose sleeve into the body such that the dose sleeve rotates to rotate the threaded sleeve, the check drive sleeve, and the lead screw. In some examples, the step of delivering the dose includes rotating the check drive sleeve without linear movement relative to the pen housing. In some examples, the step of delivering the dose includes advancing the lead screw via the threads of the threaded nut by an amount equal to the rotation angle multiplied by the pitch of the threads of the lead screw. In some examples, the step of delivering the dose includes interrupting the application of force to the dose button prior to completion of the injection (e.g., midway through the injection) such that the dose sleeve may be rotated to zero and the dose cancelled and/or continued to apply force to the dose button to continue the injection. In some examples, the step of delivering the dose includes a last dose nut that changes position, e.g., moves the threaded sleeve upward during dose dialing. In some examples, as the last dose nut advances to the top of the threaded sleeve, the last dose nut abuts and/or engages the threaded sleeve in a fixed orientation and prevents further clockwise movement of the dose selector, which limits the size of the last dose that can be dialed.
In some examples, the present delivery system includes a drug delivery pen for use with a method for dispensing a drug to a patient, the method including the step of resisting and/or preventing a pawl or ratchet arm at one end of a non-return drive sleeve from resisting torque transmitted from a dose sleeve to overcome a smaller pawl or ratchet arm of a dual ratchet and torque to drive a threaded sleeve by engaging axial teeth of the dose sleeve. In some examples, the present drug delivery system includes a drug delivery pen for use with a method for dispensing a drug to a patient, the method comprising axial ratchet engagement between a threaded sleeve and a dual ratchet such that during dose setting or dose correction, axial teeth of the threaded sleeve and the dual ratchet move relative to each other, and during dose delivery, axial teeth of the threaded sleeve and the dual ratchet are axially engaged by a user, causing the dose sleeve and the threaded sleeve to rotate such that the non-return drive sleeve rotates and drives a lead screw to deliver a dose.
In some examples, the present delivery system includes a drug delivery pen for use with a method for dispensing a drug to a patient, the method including the step of preventing rotation of the dual ratchet by large ratchet teeth during dose correction, the large ratchet teeth rattling/deflecting small diameter ratchet arms over ratchet features when the dose sleeve is rotated to select a lower dose. In some examples, the drug delivery pen allows for small axial movements of the threaded sleeve during dose dialing. In some examples, the present drug delivery system includes a drug delivery pen for use with a method for dispensing a drug to a patient, the method including the step of preventing a back rotation of a check drive sleeve. In some examples, the present drug delivery system includes a drug delivery pen for use with a method for dispensing a drug to a patient, the method including the step of preventing dialing a dose greater than an amount of insulin that can be delivered from a cartridge, for example, by a last dose nut. In some examples, the last dose nut is rotationally keyed to the dose sleeve and is free to move axially along the device axis.
The present disclosure may be understood more readily by reference to the following detailed description of the examples taken in conjunction with the accompanying drawings, which form a part of this disclosure. It is to be understood that this application is not limited to the particular devices, methods, conditions, or parameters described and/or shown herein, and that the terminology used herein is for the purpose of describing particular examples by way of example only and is not intended to be limiting. In some examples, as used in the specification and including the appended claims, the singular forms "a," "an," and "the" include plural referents, and reference to a particular value includes at least the particular value unless the context clearly dictates otherwise. Ranges may be expressed herein as from "about" or "approximately" one particular value, and/or to "about" or "approximately" another particular value. When such a range is expressed, another example includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent "about," it will be understood that the particular value forms another example. It should also be understood that all spatial references, such as, for example, horizontal, vertical, top, upper, lower, bottom, left and right, are for illustrative purposes only and may be varied within the scope of the present disclosure. For example, references to "upper" and "lower" are relative and are used only in the context of one another, and are not necessarily "upper" and "lower".
As used in the specification and including the appended claims, "treatment" of a disease or disorder may include administration of one or more drugs to a patient (human or other mammal). Remission may occur before the appearance of signs or symptoms of the disease or disorder, as well as after its appearance. Thus, treatment includes preventing a disease or an undesired condition (e.g., preventing a disease from occurring in a patient who may be susceptible to the disease but has not yet been diagnosed as having the disease). Furthermore, treatment need not completely alleviate signs or symptoms, need not be curative, and specifically includes procedures that have only marginal effects on the patient. Treatment may include inhibiting the disease, e.g., preventing its progression, or alleviating the disease, e.g., causing regression of the disease. For example, treatments include, but are not limited to, reducing acute or chronic inflammation, inducing antiplatelet effects, lowering hypertension, and lowering cholesterol.
In some examples, the drug dose includes each individual release of the substance into the body tissue. In some examples, the bioactive substance includes any one or more substances, including medicaments, drugs, or medicines, including active therapeutic substances, metabolites, hormones, steroids, vitamins, fatty acids, amino acids, sugars, carbohydrates, polypeptides, or minerals. In some examples, a bioactive substance includes any substance used to treat, prevent, diagnose, cure, or alleviate a disease or disorder. In some examples, the bioactive substance includes any substance that affects anatomical structures or physiological functions. In some examples, the bioactive substance includes any substance or metabolite thereof that alters the effect of an external effect on the animal.
In some examples, the bioactive substance includes a drug-containing flowable drug that is released into the body tissue in a controlled manner, such as, for example, a liquid, solution, gel, or fine suspension. In some examples, the pharmaceutical comprises one or more pharmaceutical products, e.g., peptides, proteins (such as insulin, insulin analogs, and C-peptides), hormones, biologically derived or active agents, hormonal and gene based agents and/or nutritional formulas. In some examples, bioactive substances as described herein may be used to treat and/or prevent diabetes or complications associated with diabetes, such as diabetic retinopathy, thromboembolic disorders (such as deep vein or pulmonary thromboembolism), acute coronary syndrome, angina pectoris, myocardial infarction, cancer, macular degeneration, inflammation, pollinosis (hay fever), atherosclerosis, and/or rheumatoid arthritis.
The following discussion includes a description of a dispensing system including a drug injection device, related components, and methods of using the dispensing system. Alternative examples are also disclosed. Reference is made in detail to examples of the present disclosure that are illustrated in the accompanying drawings. Turning to fig. 1-4, components of a dispensing system including a medication injection pen 10 are shown.
The components of the medication injection pen 10, individually or collectively, may be fabricated from materials suitable for storage and dispensing of medications. In some examples, such materials include metals, ceramics, synthetic polymers such as thermoplastics, semi-rigid and rigid materials, elastomers, fabrics, and/or composites thereof. The various components of the medication injection pen 10 have a composite of materials including the materials described above to achieve various desired characteristics, such as strength, rigidity, elasticity, compliance, and durability. The components of the medication injection pen 10, individually or collectively, may also be made of heterogeneous materials, such as combinations of two or more of the materials described above. The components of the medication injection pen 10 are integrally formed, integrally connected, or include fastening elements and/or instruments, as described herein.
The medication injection pen 10 includes a housing 12 defining a longitudinal axis a and supporting dose setting and drive components, as described herein. Housing 12 is connected to a cartridge housing 14 that supports a drug cartridge 16. The medication injection pen 10 includes a pen cap 18 to selectively cover the medication cartridge 16 and the cartridge housing 14. In some examples, as shown in fig. 5-9, the cartridge housing 14 is attached to the housing 12 via one or more protrusions 20 and/or the cap 18 is removably attached to the cartridge housing 14 via a flange 22. In some examples, the cartridge housing 14 is disposed in an interference orientation with the nut 24, as described herein.
In some examples, the cap 18 blocks ultraviolet light and provides a pocket clip. In some examples, the cap 18 protects the pen needle during storage. In some examples, cap 18 protects drug cartridge 16 and may absorb shocks during a drop. In some examples, cap 18 is held on drug cartridge 16 in any orientation, e.g., an orientation that prevents cap 18 from rotating cartridge housing 14 until a torque limit, an orientation that supports the weight of drug cartridge 16, an orientation that provides visual indicia of the contents of drug cartridge 16, an orientation that provides visual indicia of the plunger, and/or a visual indicia that provides a scale of drug cartridge 16 to inform the user of the general orientation of the remaining contents. In some examples, the pen cap 18 allows for needle removal, needle attachment, and needle access to the needle cannula of the cartridge septum. In some examples, rotation of the cap 18 is limited when installed in a particular orientation.
The dose member (e.g. the dose sleeve 26) has a dose setting knob 28 which is rotatable to set a desired dose. A dose set knob 28 is provided with the proximal end of the dose sleeve 26. The dose sleeve 26 comprises a number corresponding to the dosage unit visible through a window 31 provided on the housing 12. The dose setting knob 28 is rotatable to set a desired dose, which is visible through the window 31. The housing 12 includes an indicator 32 that provides tactile and/or visual indicia of the set dose. In some examples, the dose set knob 28 includes a gripping surface. In some examples, as shown in fig. 10-12, the dose sleeve 26 includes a stop 34 and the housing 12 includes a stop 36, the stop 36 being engageable to define a zero dose stop angular position during dose setting, the zero dose stop angular position corresponding to the end of dose position.
The outer surface of the dose sleeve 26 threadedly engages the inner surface of the housing 12. The dose sleeve 26 comprises a wall having an outer helical track engageable with a helical rib along the wall of the housing 12. In some examples, as shown in fig. 13, the threaded form of the dose sleeve 26 and/or the housing 12 includes an axial clearance of about 0.2 to 0.3mm and a radial clearance of 0.15 mm.
A drive member (e.g., drive sleeve 38) has an enlarged proximal end 30 and a wall defining a longitudinal slot 47. The drive sleeve 38 fits into the dose sleeve 26 and over a drive member (e.g., the check drive sleeve 42). In some examples, the drive sleeve 38 engages with a dog clutch of the dose sleeve 26 having teeth, as described herein. The drive sleeve 38 is keyed to the check drive sleeve 42 and, as described herein, the nut 24 is secured with the housing 12. The sleeve 42 has a wall including splines 45, the splines 45 sliding within slots 47 such that the sleeve 38, 42 is fixed in rotation and is capable of relative axial translation.
The nut 24 has internal threads and is secured to the housing 12. The nut 24 includes an outer surface having one or more locking elements 46, the locking elements 46 matingly engaging the one or more locking elements of the inner surface of the housing 12 to lock the nut 24 against rotation relative to the housing 12, as shown in fig. 14. The piston rod 48 has an external thread that is engageable with the internal thread of the nut 24 and rotates through the internal thread of the nut 24. The piston rod 48 has a distal end connected to a presser foot and providing a bearing 50 for the presser foot, which is rotatable relative to the piston rod 48 and is engageable with the plunger of the drug cartridge 16.
The check drive sleeve 42 is supported by the nut 24 to prevent relative axial movement of the check drive sleeve 42 and to permit one-way rotation of the check drive sleeve 42 relative to the nut 24 via the check ratchet 52, as shown in fig. 15. The check ratchet 52 acts between the check drive sleeve 42 and the nut 24. In some examples, the non-return ratchet 52 prevents the medication injection pen 10 from being back driven due to back pressure from the medication cartridge 16, and prevents the user from winding the piston rod 48 back into the housing 12, which would move the piston rod 48 away from the plunger of the medication cartridge 16. In some examples, the check ratchet 52 controls incremental rotational stepping of the piston rod 48 as the piston rod 48 rotates.
The check ratchet 52 includes one or more ratchet arms that engage the ratchet profile of the nut 24, as described herein, to prevent rotation of the check drive sleeve 42 in one direction (e.g., a dose setting direction), for example, and to allow rotation of the check drive sleeve 42 in an opposite direction (e.g., a dose dispensing direction). For example, as shown in fig. 15 and 17, the check drive sleeve 42 includes ratchet arms 80 having teeth 84, and the nut 24 includes internal teeth 82. The teeth 82 each include a face 83 and a back drive face 85, the back drive face 85 increasing back drive resistance during engagement with the teeth 84, for example, during dose setting to prevent rotation of the drive sleeve 38 and/or the check drive sleeve 42 relative to the housing 12 during dose setting. In some examples, nut 24 includes a circumferential wall 25 such that face 83 extends from wall 25 to define radius R. In some examples, face 83 defines an arc, which may have a uniform radius in some examples. In some examples, the face 83 may define alternative configurations, such as variable radius, linear, arcuate, planar, contoured, offset, increasing or decreasing slope, taper, or spiral. In some examples, teeth 82 each include a tooth tip, such as a snap over radius (snap over radius) 87 as described herein, disposed between face 83 and face 85 adjacent a middle portion of the tooth profile of teeth 82. In some examples, the tooth profile of the tooth 82 transitions from the top of the tooth to an adjacent tooth profile along the dip. In some examples, the gear profile of the teeth 82 transitions down from the top of the teeth along a steep or sharp angle to define a greater back drive resistance to prevent rotation of the drive sleeve 38 and/or the check drive sleeve 42 relative to the housing 12 during dose setting.
Teeth 84 can engage face 83 during dose dispensing to allow rotation of drive sleeve 38 and/or check drive sleeve 42 relative to housing 12. The ratchet arm 80 of the non-return drive sleeve 42 follows the internal teeth 82 such that the ratchet profile including the teeth 84 engages the internal teeth 82 to contact the respective faces of the rotating teeth 84 and the teeth 82 through flat surfaces and the surfaces slide over one another. During dose setting, the teeth 84 can engage the counter drive surface 85 to prevent rotation of the drive sleeve 38 and/or the check drive sleeve 42 relative to the housing 12. The engagement of teeth 84 and teeth 82, due to their respective configurations as described herein, prevents rotation of the check drive sleeve 42 and drive sleeve 38 in the dose setting direction and allows rotation of the check drive sleeve 42 in the dose dispensing direction by its keyed connection with the check drive sleeve 42.
In some examples, as shown in fig. 16, the housing 12 includes a spacer 113, the spacer 113 including a continuous circular configuration that supports, guides, and/or aligns components of the non-return ratchet 52 as described herein with the housing 12. In some examples, engagement of teeth 84 and 82 define a torque gradient that decreases linearly as the respective faces slide over one another due to their respective configurations as described herein. In some examples, as used herein, a "linearly decreasing torque gradient" is understood to mean that the rate of change of torque gradually decreases in a continuous manner (as opposed to stepwise), and is in no way limited to a strictly linear relationship in a mathematical sense. In some examples, tooth 82 includes a snap radius 87 disposed between face 83 and face 85, snap radius 87 guiding and/or adjusting movement of tooth 84 as tooth 84 slides from face 83 to face 85.
In some examples, the check ratchet 52 has one or more ratchet arms of the check drive sleeve 42, each ratchet arm including a ratchet profile having teeth 184, the teeth 184 following the internal teeth 182 of the nut 24, as shown in fig. 17-19. In some examples, the teeth 184 have a uniform and/or continuous radius such that the non-return ratchet 52 provides performance characteristics including a torque curve as depicted in the graphical representation shown in fig. 20. In some examples, the non-return ratchet 52 maintains resistance to movement while reducing the peak torque required when rotation is initiated. In some examples, the non-return ratchet 52 includes a ratchet profile having the form of teeth including a tooth shape having a uniform and/or continuous radius that prevents abrupt changes in torque. In some examples, as shown in fig. 21-23, the ratchet profile of the non-return ratchet 52 is selectively sized to provide performance characteristics as depicted in the graphical representations shown in fig. 24-26, respectively. In some examples, engagement of teeth 84 with face 83 produces a peak torque in the range of about 2.00 to 3.00 Nmm. In some examples, engagement of teeth 84 with face 85 produces a maximum backdrive drag torque in the range of about 3.00 to 6.00 Nmm.
In some examples, the check ratchet 52 has a 2-arm configuration of the check drive sleeve 42, with each arm 242 including a ratchet profile having teeth 252 that follow the internal teeth 290 of the nut 24, as shown in fig. 27 and similar to that described herein. In some examples, engagement of teeth 252 with teeth 290 during dose dispensing produces a peak torque in the range of about 1.00 to 2.00 newton millimeters (Nmm). In some examples, as shown in fig. 28 and similar to that described herein, the non-return ratchet 52 has a 3-arm configuration of the non-return drive sleeve 42, the 3-arm configuration including a first circumferential arm 334 having teeth 352, a second circumferential arm 334 having teeth 352, and a third circumferential arm 334 having teeth 352, the arms 334 being substantially equally spaced about the non-return drive sleeve 42. In some examples, as used herein with respect to the arms, "substantially equidistant" refers to the arms being spaced as nearly equidistant as possible in view of the number of teeth and geometry of the nut. For example, in the non-limiting example shown in fig. 28, the arms are considered "approximately equidistant" (in this non-limiting example, one less tooth 52 of the shorter nut 24) even though one of the spaces between the teeth 352 of the circumferential arms 334 is slightly smaller than the other two spaces, since the total number of teeth 52 of the nut 24 is not divisible by 3. Each arm 334 has a ratchet profile that includes teeth 352 that follow the internal teeth 390 of the nut 24. The arm 334 is configured for disposition with the nut 24 such that the check drive sleeve 42 is coaxially aligned with the axis a of the housing 12. In some examples, the arm 334 is provided with the nut 24 such that the check drive sleeve 42 is configured for self-centering and/or self-positioning with the nut 24 for coaxial orientation with the axis a. In some examples, engagement of teeth 352 with teeth 390 produces a peak torque in the range of about 2.00 to 3.00 Nmm. A comparison of the performance characteristics of the 2-arm and 3-arm configurations of the non-return ratchet 52 including the torque curve is depicted in the graphical representations shown in fig. 29-31. In some examples, the non-return ratchet 52 includes a 3-arm configuration with an even number of positions and an odd number of arms and teeth, such that teeth 352 and 390 are configured to provide audible and tactile feedback, including a single click per tooth.
The click member, for example, the double ratchet 84 has a ratchet (e.g., a small ratchet 90) and a ratchet (e.g., a large ratchet 92), as shown in fig. 32 to 36. The dual ratchet 84 is attached to the dose button 54 via a snap ring or the like and is positioned on the top surface of the drive sleeve 38. The small ratchet 90 includes a single-arm configuration and has an arm 94. The arm 94 includes a bearing 96 and teeth 98, the bearing 96 and teeth 98 forming a ratchet profile with the internal teeth 100 of the drive sleeve 38 such that the teeth 98 follow the internal teeth 100. The teeth 98 engage the internal teeth 100 to rotate the respective faces of the teeth 98 and 100 by flat surface contact, and the two surfaces slide over each other. The engagement of teeth 98 and teeth 100, due to their respective configurations as described herein, allows relative rotation between dual ratchet 84 and drive sleeve 38 in a first direction to provide, for example, tactile and/or audible indicia/feedback, and prevents relative rotation between dual ratchet 84 and drive sleeve 38 in a second, opposite direction. The large ratchet 92 includes a single-arm configuration and has an arm 102. Arm 102 includes bearing 104 and teeth 106, bearing 96 and teeth 106 forming a ratchet profile with internal teeth 108 of dose sleeve 26 such that teeth 98 follow internal teeth 108. Teeth 106 engage internal teeth 108 to rotate the respective faces of teeth 106 and 108 through flat surface contact, and the two surfaces slide over each other. The engagement of teeth 106 and 108 allows relative rotation between dual ratchet 84 and drive sleeve 26 in a first direction due to their respective configurations as described herein to provide, for example, tactile and/or audible indicia/feedback, and prevent relative rotation between dual ratchet 84 and dose sleeve 26 in a second, opposite direction.
The small ratchet 90 interacts with the drive sleeve 38 and the large ratchet 92 interacts with the dose sleeve 26. In some examples, when the user reduces the dose, the non-return ratchet 52 resists torque from the small ratchet 90 to avoid back pressurization of the cartridge 16. In some examples, when a dose is set with the dose sleeve 26, the teeth 98 of the small ratchet 90 resist rotation such that the large ratchet 92 deflects over the teeth 108 of the dose sleeve 26 and rattles, and the teeth 108 of the large ratchet 92 prevent rotation of the dual ratchet 84 during a reduction in the set dose, which causes the teeth 98 of the small ratchet 90 to deflect over the teeth 100 of the drive sleeve 38 and rattle when the dose sleeve 26 rotates to select a lower dose. In some examples, the pawls of the ratchet arms of the check drive sleeve 42 may resist torque transferred from the dose sleeve 26 to overcome the small ratchet 90 and resist torque to lift the drive sleeve 38 out of engagement with the axial teeth of the dose sleeve 26.
The large ratchet 92 provides tactile feedback during dose setting. The small ratchet 90 provides tactile feedback during a reduction of the set dose. In some examples, small ratchet 90 is more flexible and/or less rigid relative to non-return ratchet 52 to avoid back pressurization of cartridge 16 when the user reduces the dose. In some examples, the non-return ratchet 52 includes an arm ratchet having opposing bearing surfaces to maintain the dual ratchet 84 in a centered position relative to the housing 12. In some examples, the large ratchet 92 includes a bearing surface and a rounded and/or arcuate tooth form to create a continuous running surface. In some examples, the small ratchet 90 includes a circular and/or arcuate tooth form to create a continuous running surface. In some examples, the teeth 98 of the small ratchet 90 move and/or slide over the teeth 100 of the drive sleeve 38 during the dial-up or dial-down of a selected dose with the dose sleeve 26. In some examples, during dose delivery of a selected dose using user actuation pressure applied to dose button 54, teeth 98 of small ratchet 90 translate axially and engage teeth 100 of drive sleeve 38 such that dose sleeve 26 and drive sleeve 38 are rotationally fixed, thereby causing check drive sleeve 42 to rotate, rotationally fixed with drive sleeve 38 such that piston rod 48 rotates and translates axially to deliver the set dose. In some examples, teeth 106 of large ratchet 92 engage teeth 108 of dose sleeve 26 and prevent rotation of dual ratchet 84 during downward dialing, which causes teeth 98 of small ratchet 90 to deflect and rattle over teeth 100 of drive sleeve 38 when dose sleeve 26 rotates to select a lower dose. In some examples, the drive sleeve 38 includes axial movement and/or play during dose setting.
The dose sleeve 26 is threadably connected with the housing 12 and the drive sleeve 38 is supported by the dose sleeve 26 and is fixable with the dose sleeve 26. The drive sleeve 38 is in keyed engagement with the check drive sleeve 42, and the check drive sleeve 42 can be engaged with the piston rod 48 and rotationally fixed, as described herein. The piston rod 48 extends through the check drive sleeve 42. The check drive sleeve 42 includes an inner surface having a non-circular cross-section that is engageable with an outer surface of the piston rod 48. The outer surface of the piston rod 48 has a non-circular cross-section. Rotation of the check drive sleeve 42 is transmitted to the piston rod 48, thereby preventing rotation of the piston rod 48 relative to the check drive sleeve 42. The piston rod 48 is threadedly connected with the internal thread of the nut 24 such that the piston rod 48 translates in a distal direction through the nut 24 and relative rotational movement therebetween translates rotational movement of the piston rod 48 into linear movement. The piston rod 48 engages a plunger bearing 50 and the bearing 50 transfers axial force to the plunger. In this way, the piston rod 48 is allowed to move axially in a distal direction relative to the check drive sleeve 42 as the external thread of the piston rod 48 engages the internal thread of the nut 24 such that the piston rod 48 rotates through the nut 24 to dispense a selected dose of medicament.
To set a dose of medication with the medication injection pen 10, as shown in fig. 37, the user rotates the dose sleeve 26 with the dose set knob 38. In some examples, the dose sleeve 26 may be rotated for dialing, reducing, and canceling a set dose. For example, as shown in fig. 38, to set a selected medicament dose, the dose set knob 28 is rotated to rotate the dose sleeve 26 in a clockwise direction when viewed from the end of the dose button 54 of the medicament injection pen 10, which translates the dose sleeve 26 in a proximal direction and out of the housing 12. The dose incremental click is provided by the teeth 106 of the large ratchet 92 of the dual ratchet 84 clicking over the teeth 108 of the dose sleeve 26, as described herein. The piston rod 48 and the check drive sleeve 42 do not rotate as prevented by the check ratchet 52 and the components of the check drive sleeve 42 and the nut 24, as described herein.
The maximum selectable dose is determined by the maximum extension of the check drive sleeve 42 outwardly from the threaded sleeve 38 and in a proximal direction from the threaded sleeve 38, as limited by the final dose nut 110, as shown in fig. 39 and 40. Upon reaching the amount of drug remaining in drug cartridge 16, last dose nut 110 prevents rotation of dose sleeve 26 to prevent selection of a dose greater than the maximum dose and/or the amount of drug remaining in cartridge 16. The drive sleeve 38 is threadedly engaged with the last dose nut 110. The last dose nut 110 is keyed to the dose sleeve 26 via a spline and slot arrangement and is rotatably fixed with the dose sleeve 26 and rotatable relative to the drive sleeve 38 when the last dose nut 110 is rotatable with the threads of the drive sleeve 38. In some examples, this configuration causes the large ratchet 92 to deflect and rattle over the teeth 108 of the dose sleeve 26.
The last dose nut 110 is keyed to the dose sleeve 26 and the drive sleeve 38 has an outer surface that includes threads such that the last dose nut 110 follows the thread path of the drive sleeve 38. Finally the dose nut 110 rotates relative to the drive sleeve 38 and axially translates along the drive sleeve 38 by an amount corresponding to the rotation during dose dialing. When the last dose nut 110 reaches the top of the drive sleeve 38, as shown in fig. 40 and 41, the last dose nut 110 is secured to the drive sleeve 38 and prevents further clockwise movement of the dose sleeve 26. This configuration of the final dose nut 110 limits the size of the final dose that can be dialed. In some examples, the distal end of the dose sleeve 26 engages the nut 38 to prevent setting the dose below a selected zero amount of medicament in the medicament cartridge 16.
To reduce or cancel a set dose, the dose sleeve 26 with the dose set knob 28 is rotated, for example, in a counter-clockwise direction. The dual ratchet 84 rotates with the dose sleeve 26 and the teeth 98 of the small ratchet 90 of the dual ratchet 84 rattle over the teeth 100 of the drive sleeve 38. The piston rod 48 and the check drive sleeve 42 do not rotate because the teeth 84 of the check drive sleeve 42 are harder and/or more rigid than the teeth 98 of the drive sleeve 38. When one or more doses are dialed, reduced or cancelled, the last dose nut 110 translates in a proximal or distal direction to advance the drive sleeve 38 up and down.
To deliver a dose, as shown in fig. 42, the dose button 54 is actuated by a user and the teeth 112 of the drive sleeve 38 are driven into engagement with the teeth 114 of the dose sleeve 26 for rotational securement therebetween. Such engagement rotates the dose sleeve 26, for example, in a counter-clockwise direction, and translates the dose sleeve 26 in a distal direction into the housing 12. As the dose sleeve 26 rotates, the drive sleeve 38, the check drive sleeve 42 and the piston rod 48 rotate in a counter-clockwise direction due to their component connections, as described herein. The check drive sleeve 42 rotates but does not axially translate relative to the housing 12. In some examples, axial translation of piston rod 48 in the distal direction via the internal thread of nut 38 is equal to the angle of rotation multiplied by the pitch of piston rod 48 such that bearing 50 engages the plunger of cartridge 16 to dispense the set dose of medicament.
In some examples, if the user stops pressing the dose button 54 during an injection, the user may rotate the dose sleeve 26 to the zero position and cancel the set dose, or continue the injection by pressing the dose button 54. When a dose is delivered, the last dose nut 110 does not change its position on the drive sleeve 38.
In some examples, bearing 50 transfers the axial force of piston rod 48 to cartridge 16 such that the plunger limits torque transfer and propagates the point load from piston rod 48 to the plunger surface. In some examples, the dose sleeve 26 supports a dual ratchet 48 and displays a selected dose.
In some examples, the medication injection pen 10 includes a child resistant feature while being easy for an adult to use. For example, the medication injection pen 10 includes a component that is movable between a child-resistant, locked, and/or medication-inaccessible configuration and an unlocked and/or medication-accessible configuration. In some examples, instructional markers are located with the housing 12.
It should be understood that various modifications may be made to the examples disclosed herein. Accordingly, the above description should not be construed as limiting, but merely as exemplifications. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto.