US20070232928A1 - Medical ultrasound system and handpiece and methods for making and tuning - Google Patents

Abstract

Several embodiments of medical ultrasound handpieces are described each including a medical ultrasound transducer assembly. An embodiment of a medical ultrasound system is described, wherein the medical ultrasound system includes a medical ultrasound handpiece having a medical ultrasound transducer assembly and includes an ultrasonically-vibratable medical-treatment instrument which is attachable to a distal end of the transducer assembly. An embodiment of a medical ultrasound system is described, wherein the medical ultrasound system has a handpiece including a medical ultrasound transducer assembly and including a housing or housing component surrounding the transducer assembly. A method for tuning a medical ultrasound handpiece includes machining at least a distal non-threaded portion of an instrument-attachment stud of the transducer assembly to match a measured fundamental frequency to a desired fundamental frequency to within a predetermined limit. A method for making a medical ultrasound transducer assembly determines acceptable gains for gain stages of the transducer assembly.

Description

CROSS REFERENCE TO RELATED APPLICATIONS
• The present application claims the priority benefit of U.S. provisional patent application Ser. No. 60/726,625, filed on Oct. 14, 2005.
FIELD OF THE INVENTION
• The present invention is related generally to medical equipment, and more particularly to a medical ultrasound handpiece having a medical ultrasound transducer assembly, to a method for tuning the handpiece, to a method for making the transducer assembly, and to a medical ultrasound system including a handpiece and an ultrasonically-vibratable medical-treatment instrument which is attachable to the distal end portion of the transducer assembly of the handpiece.
BACKGROUND OF THE INVENTION
• Medical ultrasound systems are known which include a medical ultrasound handpiece having a medical ultrasound transducer assembly and which include an ultrasonically-vibratable medical-treatment instrument attached to the distal end portion of the transducer assembly of the handpiece. Examples of such instruments include an ultrasonically vibrating scalpel and include an ultrasonic clamp having a first clamp arm which is an ultrasonically vibrating blade and having a second non-vibrating clamp arm. In one known application, the scalpel/blade vibrates at a fundamental frequency (i.e., a resonant frequency of displacement along the longitudinal axis of the instrument).
• Conventional medical ultrasound systems provide the instrument with a desirable high displacement (i.e., a large vibrational amplitude) by employing a relatively large size transducer assembly resulting in a relatively large size handpiece which is unsuitable for a surgeon to hold and use in precise and delicate surgery.
• Still, scientists and engineers continue to seek improved medical ultrasound handpieces having a medical ultrasound transducer assembly and improved systems and methods related thereto.
SUMMARY
• A first expression of a first embodiment of the invention is for a medical ultrasound handpiece including a medical ultrasound transducer assembly. The transducer assembly includes consecutive first and second half-wave sections, wherein the first half-wave section includes a first node and the second half-wave section includes a second node. The first half-wave section includes a first piezoelectric transducer disk substantially centered about the first node, and the second half-wave section includes a second piezoelectric transducer disk substantially centered about the second node. The transducer assembly includes a gain stage located between the first and second piezoelectric transducer disks.
• A first expression of a second embodiment of the invention is for a medical ultrasound handpiece including a medical ultrasound transducer assembly. The transducer assembly includes consecutive first and second half-wave sections, wherein the first half-wave section includes a first node and the second half-wave section includes a second node. The first half-wave section includes a first stacked plurality of piezoelectric transducer disks substantially centered about the first node, and the second half-wave section includes a second stacked plurality of piezoelectric transducer disks substantially centered about the second node. The transducer assembly includes a gain stage located between the first and second stacked pluralities of piezoelectric transducer disks.
• A second expression of a second embodiment of the invention is for a medical ultrasound handpiece including a 1½-wave medical ultrasound transducer assembly. The transducer assembly includes consecutive first, second, and distal-most third half-wave sections, wherein the first half-wave section includes a first node, the second half-wave section includes a second node, and the third half-wave section includes a third node. The first half-wave section includes a first stacked plurality of piezoelectric transducer disks substantially centered about the first node, and the second half-wave section includes a second stacked plurality of piezoelectric transducer disks substantially centered about the second node. The transducer assembly includes a first, second, and third gain stages. The first gain stage is located in the first half-wave section distal the first stacked plurality of piezoelectric transducer disks. The second gain stage is located in the second half-wave section distal the second stacked plurality of piezoelectric transducer disks. The third gain stage extends distally from proximate the third node.
• A first expression of a third embodiment of the invention is for a medical ultrasound handpiece including a 1-wave medical ultrasound transducer assembly. The transducer assembly includes consecutive first and distal-most second half-wave sections, wherein the first half-wave section includes a first node and the second half-wave section includes a second node. The first half-wave section includes a first stacked plurality of piezoelectric transducer disks, and the second half-wave section includes a second stacked plurality of piezoelectric transducer disks. The transducer assembly includes first and second gain stages, wherein the first gain stage is located in the first half-wave section distal the first stacked plurality of piezoelectric transducer disks, and wherein the second gain stage is located in the second half-wave section distal the second stacked plurality of piezoelectric transducer disks.
• A first expression of a fourth embodiment of the invention is for a medical ultrasound handpiece including a ½-wave medical ultrasound transducer assembly. The transducer assembly includes a proximal antinode, a distal antinode, and a node located between the proximal and distal antinodes. The transducer assembly includes a first stacked plurality of piezoelectric transducer disks located proximal the node, a second stacked plurality of piezoelectric transducer disks located distal the node, and a gain stage located distal the second stacked plurality of piezoelectric transducer disks.
• A first expression of a fifth embodiment of the invention is for a medical ultrasound system including a medical ultrasound transducer assembly and an ultrasonically-vibratable medical-treatment instrument. The transducer assembly has a gain of unity and has a distal end portion. The instrument is attachable to the distal end portion of the transducer assembly and has at least one gain stage.
• A first expression of a sixth embodiment of the invention is for a medical ultrasound system including a medical ultrasound transducer assembly and an ultrasonically-vibratable medical-treatment instrument. The transducer assembly has a distal end portion. The instrument is attachable to the distal end portion of the transducer assembly. The transducer assembly and the attached instrument together have an operating wavelength. The transducer assembly alone has a length which is at least equal to ¼of the operating wavelength and which is less than ½ of the operating wavelength. The transducer assembly and the attached instrument together have a length equal to N times ½ of the operating wavelength, wherein N is a non-zero positive whole number.
• A first expression of a seventh embodiment of the invention is for a medical ultrasound handpiece including a medical ultrasound transducer assembly. The transducer assembly has first and second nodes. The transducer assembly has a first transducer-assembly-to-housing mounting feature located proximate the first node and a second transducer-assembly-to-housing mounting feature located proximate the second node. The transducer assembly lacks any additional transducer-assembly-to-housing mounting feature.
• A first expression of an eighth embodiment of the invention is for a medical ultrasound handpiece including a medical ultrasound transducer assembly and an annular connector assembly. The transducer assembly includes a metallic end-mass component, a piezoelectric transducer disk, and an electrode. The piezoelectric transducer disk is located distal the end-mass component and is in electrical contact with the electrode. The connector assembly surrounds the transducer assembly, is in electrical contact with the electrode, and is electrically connectable to an ultrasound electric generator.
• A second expression of an eighth embodiment of the invention is for a medical ultrasound handpiece including a medical ultrasound transducer assembly and an annular connector assembly. The transducer assembly includes a metallic end-mass component, a stacked plurality of piezoelectric transducer disks, and electrodes. The stacked plurality of piezoelectric transducer disks is located distal the end-mass component. Each piezoelectric transducer disk is in electrical contact with a corresponding electrode. The connector assembly surrounds the transducer assembly, is in electrical contact with the electrodes, and is electrically connected to a cable socket which is electrically connectable to an ultrasound electric generator.
• A first expression of a ninth embodiment of the invention is for a medical ultrasound handpiece including a medical ultrasound transducer assembly, an inner conductive ring, and an outer conductive ring. The transducer assembly is electrically connectable to an ultrasound electric generator, has a longitudinal axis, and is attachable to an ultrasonically-vibratable medical-treatment instrument having a switch which has an open position and a closed position. The inner conductive ring is substantially coaxially aligned with the longitudinal axis, circumferentially surrounds the transducer assembly, and has a distally-facing first annular surface. The outer conductive ring is substantially coaxially aligned with the longitudinal axis, circumferentially surrounds the transducer assembly, and has a distally-facing second annular surface. The outer conductive ring is electrically isolated from the inner conductive ring. The first and second annular surfaces are in electric contact with the switch of the attached instrument when the switch is in the closed position. The inner and outer conductive rings are electrically connectable to the generator, and the switch of the attached instrument controls the connected generator.
• A first expression of a tenth embodiment of the invention is for a medical ultrasound handpiece including a medical ultrasound transducer assembly, a housing, a mount, and an annular bumper unit. The housing surrounds the transducer assembly. The mount pivotally attaches the transducer assembly to the housing. The bumper unit is attached to the housing and includes a plurality of spaced apart and inwardly projecting bumpers. None of the bumpers is in contact with the transducer assembly when the transducer assembly is not under a pivoting load. At least one of the bumpers is contact with the transducer assembly when the transducer assembly is under the pivoting load.
• A first expression of an eleventh embodiment of the invention is for a medical ultrasound handpiece including a medical ultrasound transducer assembly, at least one mounting member, and a first housing component. The transducer assembly has a longitudinal axis and has a substantially coaxially aligned, circumferential surface groove. The at-least-one mounting member is at-least-partially-annular and has an inner portion located in the surface groove. The first housing component surrounds the transducer assembly and has a distal end portion including an annular longitudinally-facing surface with a recessed seat. The at-least-one mounting member has at least a proximal portion located in the seat.
• Several benefits and advantages are obtained from one or more of the expressions of embodiments of the invention. In one example, one or more or all of the expressions of embodiments of the invention help enable a relatively small size medical ultrasound transducer assembly to provide an attached ultrasonically-vibratable medical-treatment instrument with a desirable high displacement (i.e., a large vibrational amplitude) resulting in a relatively small size handpiece which is suitable for a surgeon to hold and use in precise and delicate surgery.
BRIEF DESCRIPTION OF THE FIGURES
• FIG. 1 is a schematic side elevational view of a first embodiment of the invention showing consecutive first and second half-wave sections of a medical ultrasound transducer assembly of a medical ultrasound handpiece, wherein a first piezoelectric transducer disk is substantially centered about a first node of the first half-wave section and a second piezoelectric transducer disk is substantially centered about a second node of the second half-wave section;
• FIG. 2 is a perspective view of a second embodiment of the invention showing an assembled medical ultrasound handpiece including the exposed stud of the 1½-wave medical ultrasound transducer assembly of the handpiece;
• FIG. 3 is an exploded view of a portion of the handpiece ofFIG. 2 showing the medical ultrasound transducer assembly, the bumper assembly, the housing, and the nose cone assembly of the handpiece ofFIG. 2;
• FIG. 4 is a view of the transducer assembly, the bumper assembly, and the nose cone assembly ofFIG. 3, wherein the bumper assembly and the nose cone assembly are shown attached to the transducer assembly;
• FIG. 5 is a perspective schematic view of the transducer assembly ofFIG. 4 showing first and second stacked pluralities of piezoelectric transducer disks substantially centered about respective first and second nodes;
• FIG. 6 is an exploded view of the transducer assembly ofFIG. 5;
• FIG. 7 is a perspective view of the stud of the transducer assembly ofFIG. 2 with an ultrasonically-vibratable medical-treatment instrument attached thereto, wherein the instrument is shown in partial cutaway, and wherein the instrument is an ultrasonically vibratable scalpel;
• FIG. 8 is a perspective distal end view of a portion of the transducer assembly and of the nose cone assembly ofFIG. 4;
• FIG. 9 is a cross sectional view of the transducer assembly and of the nose cone assembly ofFIG. 8;
• FIG. 10 a view of a portion of the transducer assembly ofFIG. 4 with the attached bumper assembly;
• FIG. 11 is a cross sectional view of the bumper assembly ofFIG. 10;
• FIG. 12 is a perspective view of a portion of the transducer assembly and of the dielectric multi-lug ring, the dielectric washer, and the first O-ring seal of the nose cone assembly ofFIG. 9;
• FIG. 13 is a perspective view of the transducer assembly ofFIG. 12;
• FIG. 14 is a side elevational schematic view of an alternate embodiment of a handpiece wherein the transducer assembly has first and second gain stages each including a stacked plurality of piezoelectric transducer disks;
• FIG. 15 is a side elevational schematic view of a third embodiment of the invention showing a 1-wave medical ultrasound transducer assembly of a medical ultrasound handpiece and showing an ultrasonically-vibratable medical-treatment instrument which is attachable to the stud of the transducer assembly;
• FIG. 16 is a side elevational schematic view of a fourth embodiment of the invention showing a ½-wave medical ultrasound transducer assembly of a medical ultrasound handpiece and showing an ultrasonically-vibratable medical-treatment instrument which is attachable to the stud of the transducer assembly;
• FIG. 17 is a perspective view of a fifth embodiment of the invention showing a medical ultrasound system including a medical ultrasound transducer assembly having a unity-gain and including an ultrasonically-vibratable medical-treatment instrument having four gain stages;
• FIG. 18 is a side elevational schematic view of a sixth embodiment of the invention showing a medical ultrasound system including a medical ultrasound transducer assembly and an ultrasonically-vibratable medical-treatment instrument which together have an operating wavelength, wherein the transducer assembly alone has a length which is less than ½ of the operating wavelength;
• FIGS. 19 and 20 are side elevational schematic views of alternate embodiments of the system ofFIG. 18;
• FIG. 21 is a side elevational schematic view of a seventh embodiment of the invention showing a medical ultrasound handpiece including a medical ultrasound transducer assembly and a housing, wherein the transducer assembly has a first transducer-assembly-to-housing mounting feature disposed proximate a proximal node of the transducer assembly and has a second transducer-assembly-to-housing mounting feature disposed proximate a distal node of the transducer assembly;
• FIGS. 22 through 25 are side elevational schematic views of alternate embodiments of the transducer assembly of the handpiece ofFIG. 21;
• FIG. 26 is a side elevational schematic view of an eighth embodiment of the invention showing a medical ultrasound handpiece connected to an ultrasound electric generator with the end cap and the housing of the handpiece shown in cutaway;
• FIG. 27 is an enlarged side elevational view of the annular connector assembly and a portion of the medical ultrasound transducer assembly of the handpiece ofFIG. 26;
• FIG. 28 is a perspective view of the end cap, the cable socket, the annular connector assembly, and the medical ultrasound transducer assembly of the handpiece ofFIG. 26;
• FIG. 29 is an exploded view of the assemblage ofFIG. 28;
• FIG. 30 is a schematic view of a ninth embodiment of the invention showing a medical ultrasound handpiece connected to an ultrasound electric generator, wherein portions of the handpiece are shown in cutaway;
• FIG. 31 is a cross sectional view of the transducer assembly of the handpiece ofFIG. 30 taken along lines31-31 ofFIG. 30;
• FIG. 32 is a perspective view of a distal end portion of the handpiece ofFIG. 30 connected to a proximal end portion of an ultrasonically-vibratable medical-treatment instrument which includes a switch which controls the generator;
• FIG. 33 is a perspective view of a tenth embodiment of the invention showing a medical ultrasound handpiece including a housing (shown in cutaway), a medical ultrasound transducer assembly, a mount (shown in cutaway) pivotally attaching the transducer assembly to the housing, and a bumper unit attached to the housing;
• FIG. 34 is a proximal end view of the transducer assembly and the bumper unit ofFIG. 33 when the mount is not under a pivoting load;
• FIG. 35 is a proximal end view of the transducer assembly and the bumper unit ofFIG. 33 when the mount is under a pivoting load;
• FIG. 36 is a perspective view of an eleventh embodiment of the invention showing a medical ultrasound handpiece;
• FIG. 37 is an exploded view of the handpiece ofFIG. 36 showing the medical ultrasound transducer assembly (which is schematically illustrated), the at-least-one mounting member, the first housing component, and the second housing component of the handpiece ofFIG. 36;
• FIGS. 38-40 are perspective views showing intermediate stages of assembling the components ofFIG. 37 to produce the assembled handpiece ofFIG. 36;
• FIG. 41 is a cross sectional view of a distal portion of the handpiece ofFIG. 36; and
• FIG. 42 is a distal end view of the first housing component ofFIG. 37.
DETAILED DESCRIPTION
• Before explaining the several embodiments of the present invention in detail, it should be noted that each embodiment is not limited in its application or use to the details of construction and arrangement of parts and steps illustrated in the accompanying drawings and description. The illustrative embodiments of the invention may be implemented or incorporated in other embodiments, variations and modifications, and may be practiced or carried out in various ways. Furthermore, unless otherwise indicated, the terms and expressions employed herein have been chosen for the purpose of describing the illustrative embodiments of the present invention for the convenience of the reader and are not for the purpose of limiting the invention.
• It is further understood that any one or more of the following-described expressions, embodiments, examples, etc. can be combined with any one or more of the other following-described expressions, embodiments, examples, etc.
• A first embodiment of the invention is shown inFIG. 1. A first expression of the embodiment ofFIG. 1 is for amedical ultrasound handpiece10 including a medicalultrasound transducer assembly12. Thetransducer assembly12 includes consecutive first and second half-wave sections14 and16, wherein the first half-wave section14 includes afirst node18 and the second half-wave section16 includes asecond node20. The first half-wave section14 includes a firstpiezoelectric transducer disk22 substantially centered about thefirst node18, and the second half-wave section16 includes a secondpiezoelectric transducer disk24 substantially centered about thesecond node20. Thetransducer assembly12 includes again stage26 disposed between the first and secondpiezoelectric transducer disks22 and24.
• It is noted, for the purpose of describing the various embodiments of the invention, that a medical ultrasound transducer assembly is a transducer assembly which ultrasonically vibrates an ultrasonically-vibratable medical-treatment instrument (such as, without limitation, an ultrasonic scalpel or an ultrasonic clamp), when attached to the transducer assembly, in a mode of vibration at a fundamental frequency (i.e., a fundamental resonant frequency), that a node is a node of vibration (i.e., a location of zero magnitude of vibration), and that an antinode is a location of maximum magnitude of vibration. Examples of modes of vibration include, without limitation, a longitudinal mode of vibration, a torsional mode of vibration, a bending mode of vibration, and a swelling mode of vibration, wherein the transducer assembly is not limited to operating in a single mode of vibration as is known to those skilled in the art. Also, the terminology “gain stage” means a positive gain stage and is a longitudinally-extending portion of the transducer assembly which results in increased magnitude of vibration. Gain stages may be provided by a portion of the transducer assembly having at least one of a reduced diameter (as identified in some of the figures), a (constant or non-constant) taper, or being of a different material, as is known to those skilled in the art. It is pointed out that piezoelectric transducer disks are not limited to those with an outer perimeter having a circular shape and may include those with an outer perimeter having another shape such as, without limitation, an elliptical shape.
• A second embodiment of the invention is shown inFIGS. 2-13. A first expression of the embodiment ofFIGS. 2-13 is for amedical ultrasound handpiece28 including a medicalultrasound transducer assembly30. Thetransducer assembly30 includes consecutive first and second half-wave sections32 and34, wherein the first half-wave section32 includes afirst node36 and the second half-wave section34 includes asecond node38. The first half-wave section32 includes a firststacked plurality40 ofpiezoelectric transducer disks42 substantially centered about thefirst node36, and the second half-wave section34 includes a secondstacked plurality44 ofpiezoelectric transducer disks42 substantially centered about thesecond node38. Thetransducer assembly30 includes a gain stage46 (also called a first gain stage) disposed between the first and secondstacked pluralities40 and44 ofpiezoelectric transducer disks42.
• It is noted that, in one example, an electrode is disposed between adjacent piezoelectric transducer disks of a stacked plurality of piezoelectric transducer disks to energize the disks, as is known to those skilled in the art.
• In an alternate embodiment, as shown inFIG. 14, thehandpiece48 includes atransducer assembly50, wherein the gain stage52 (also called the first gain stage) of thetransducer assembly50 includes a stackedplurality54 ofpiezoelectric transducer disks42′. It is noted that the diameter of thepiezoelectric transducer disks42′ of thegain stage52 is smaller than the diameter of thepiezoelectric transducer disks42 of the firststacked plurality40. It is also noted that a decrease in diameter at a node maximizes the gain of a gain stage, and that a following increase in diameter at a distally adjacent antinode fully keeps the gain of the gain stage.
• A second expression of the embodiment ofFIGS. 2-13 is for amedical ultrasound handpiece28 including a 1½-wave medicalultrasound transducer assembly30′. Thetransducer assembly30′ includes consecutive first, second, and distal-most third half-wave sections32,34, and56, wherein the first half-wave section32 includes afirst node36, the second half-wave section34 includes asecond node38, and the third half-wave section56 includes athird node58. The first half-wave section32 includes a firststacked plurality40 ofpiezoelectric transducer disks42 substantially centered about thefirst node36, and the second half-wave section34 includes a secondstacked plurality44 ofpiezoelectric transducer disks42 substantially centered about thesecond node38. Thetransducer assembly30 includes first, second, and third gain stages46,60, and62. Thefirst gain stage46 is disposed in the first half-wave section32 distal the firststacked plurality40 ofpiezoelectric transducer disks42. Thesecond gain stage60 is disposed in the second half-wave section34 distal the secondstacked plurality44 ofpiezoelectric transducer disks42. Thethird gain stage62 extends distally from proximate thethird node58.
• It is noted that a 1½-wave transducer assembly is a transducer assembly having a length from its proximal end to its distal end of substantially 1½ wavelengths of its fundamental frequency. It is also noted that a 1½-wave transducer assembly has a proximal antinode at its proximal end (the proximal end of the first half-wave section), a common antinode of the first and second half-wave sections, a common antinode of the second and third half-wave sections, and a distal antinode at its distal end (the distal end of the third half-wave section).
• In one enablement of the second expression of the embodiment ofFIGS. 2-13, thefirst gain stage46 has aproximal end64 which is distally spaced apart from the firststacked plurality40 ofpiezoelectric transducer disks42 and has adistal end65 which is disposed proximate acommon antinode66 of the first and second half-wave sections32 and34. In one variation, thesecond gain stage60 has aproximal end68 which is distally spaced apart from the secondstacked plurality44 ofpiezoelectric transducer disks42 and has adistal end70 which is disposed proximate acommon antinode72 of the second and third half-wave sections34 and56. In one modification, the third half-wave section56 distally terminates in astud74 which is attachable to an ultrasonically-vibratable medical-treatment instrument76. In one example, thestud74 includes a proximal threadedportion78 and includes a distalnon-threaded portion80 adjoining the proximal threadedportion78, and the proximal threadedportion78 is threadably attachable to theinstrument76. Examples of non-stud and/or non-threadable attachments are left to those skilled in the art.
• In an alternate embodiment, as shown inFIG. 14, thefirst gain stage52 includes a stackedplurality54 ofpiezoelectric transducer disks42′, and thesecond gain stage82 includes a stackedplurality84 ofpiezoelectric transducer disks42′. In one variation, the third half-wave section86 includes a stackedplurality88 ofpiezoelectric transducer disks42′ having aproximal end90 which is distally spaced apart from thecommon antinode92 of the second and third half-wave sections94 and86 and having adistal end96 which is disposed proximate thethird node98.
• A method for tuning the medical ultrasound handpiece28 (wherein thehandpiece28 includes the stud74) includes steps a) through c). Step a) includes measuring a fundamental frequency of thetransducer assembly30′. Step b) includes determining a desired fundamental frequency of thetransducer assembly30′ wherein the desired fundamental frequency is greater than the measured fundamental frequency. Step c) includes machining at least the distalnon-threaded portion80 to match the measured fundamental frequency to the desired fundamental frequency to within a predetermined limit. In one variation, the machining of step c) shortens thenon-threaded portion80. In one modification, step c) also includes machining the proximal threadedportion78. It is noted that the method is not limited to a 1½-wave transducer assembly.
• A method for making an example of thetransducer assembly30′ of themedical ultrasound handpiece28 includes steps a) through g). In this method and example, there are first, second and third gain stages46,60 and62, the first, second and third gain stages46,60 and62 and theinstrument76 each have a gain, and thetransducer assembly30′ has a design diameter. Step a) includes obtaining at least one electromechanical equation of an electromechanical requirement, of drive circuitry to drive thetransducer assembly30′ with the attachedinstrument76, which depends on the design diameter and the first, second and third gain stages46,60 and62. Step b) includes obtaining at least one acoustic equation of an acoustic requirement, of stable dynamic behavior of the attachedinstrument76, which depends on the design diameter, the first, second and third gain stages46,60 and62, and the instrument gain. Step c) includes predetermining an acceptable range for each electromechanical requirement. Step d) includes predetermining an acceptable range for each acoustic requirement. Step e) includes preselecting the design diameter and the instrument gain. Step f) includes determining an acceptable first gain for thefirst gain stage46, an acceptable second gain for thesecond gain stage60, and an acceptable third gain for thethird gain stage62 using the at-least-one electromechanical equation and the at-least-one acoustic equation which place each electromechanical requirement in the acceptable range for that electromechanical requirement and each acoustic requirement in the acceptable range for that acoustic requirement. Step g) includes constructing thetransducer assembly30′ with thefirst gain stage46 having the determined acceptable first gain, with thesecond gain stage60 having the determined acceptable second gain, and with thethird gain stage62 having the determined acceptable third gain. It is noted that the design diameter is a basic diameter of the transducer assembly and does not reflect any diameter of a gain stage, any torquing flat on a component, any mounting flange of the transducer assembly to a housing, any seat of a stud which engages an instrument, and any diameter of a non-threaded portion of such stud. It is also noted that the method is not limited to a 1½-wave transducer assembly and/or to three gain stages and/or particular component composition.
• In one employment of the method for making thetransducer assembly30′, the attachedinstrument76 has a fundamental frequency. In this employment, step a) obtains an equation of the phase margin of the attachedinstrument76, an equation of the power dissipation of thetransducer assembly30′, an equation of the displacement (linear or angular depending on the mode of vibration) of the attachedinstrument76, an equation of the impedance of thetransducer assembly30′, an equation of the power transmitted to patient tissue (tissue power) by the attachedinstrument76, and an equation of the loaded maximum phase of the attachedinstrument76. It is noted that the phrase phase margin, power dissipation, displacement, tissue power, impedance, and loaded maximum phase are examples of electromechanical requirements each having an acceptable range for drive circuitry in an ultrasonic electric generator to drive thetransducer assembly30′ with the attachedinstrument76. In this employment, step b) obtains an equation of a first resonant frequency (Sn−1) next below the fundamental frequency, obtains an equation of a second resonant frequency (Sn+1) next above the fundamental frequency, and obtains an equation of the span (Span−1) of the first and second resonant frequencies. It is noted that Sn−1, Sn+1, and Span−1 are examples of acoustic requirements each having an acceptable range for stable dynamic behaviour of the attachedinstrument76.
• An example of a set of such at-least-one electromechanical equation for thetransducer assembly30′ is as follows:
  Phase Margin=4284.8+72.71*DD−422.6*TG−2488.5*HG−505.74*MG+513.4*(HG)²+26.1*(MG)²−62.8*(DD*HG)+7.44*(DD*MG)+188.9*(TG*HG)+75.3*(HG*MG);
  Power Dissipation=21.22−0.905*DD−0.784*TG−12.3*HG−5.7*MG+2.1*(HG)²+0.11*(MG)²+0.021*(DD*HG)+0.37*(DD*MG)+0.75*(TG*HG)+1.75*(HG*MG);
  Displacement=70.62−7.15*DD−0.382*TG−26.44*HG−14.12*MG+2.29*(HG)²−0.12*(MG)²+1.48*(DD*HG)+1.47*(DD*MG)+1.42*(TG*HG)+4.90*(HG*MG);
  Tissue Power=253.1+19.49*DD−17.6*TG−108.93*HG−40.8*MG+21.9*(HG)²+4.5*(MG)²−6.44*(DD*HG)−2.7*(DD*MG)+6.7*(TG*HG)+5.7*(HG*MG);
  Impedance=194.82−8.31*DD−7.2*TG−112.78*HG−52.1*MG+18.98*(HG)²+0.97*(MG)²+0.19*(DD*HG)+3.4*(DD*MG)+6.84*(TG*HG)+16.1*(HG*MG); and
  Loaded Maximum Phase=268.9+1.225*DD−6.5*TG−157.5*HG−38.7*MG+29.9*(HG)²+3.23*(MG)².
• An example of a set of such at-least-one acoustic equation for thetransducer assembly30′ is as follows:
  Sn−1=163.5*DD+228.5*IG+4001.6*TG+2149.6*HG+860.3*MG+500.5*(IG)²−1037.9*(IG*TG)−454.1*(IG*HG)−231.3*(IG*MG)−9125.7;
  Sn+1=2805.6*DD−1590.3*IG+34.4*TG+1465.6*HG+2652.4*MG−168.1*(DD)²+447.9*(IG)²−138.2*(MG)²−229.6*(IG*MG)−437.8*(HG*MG)−15212.6; and
  Span−1=3713.9*DD−2906.9*IG+2757.1*TG+274.7*HG+3160.6*MG−214.6*(DD)²+976.2*(IG)²−190*(MG)²−672.5*(IG*TG)−460.9*(IG*MG)−19879.9.
• In the above nine equations, the design diameter DD is the diameter (in millimeters) of the end-mass component100 (which is equal to the outer diameter of thepiezoelectric transducer disks42 of the first and secondstacked pluralities40 and44 of piezoelectric transducer disks42), IG is the instrument gain, the trans gain TG is the first gain, the horn gain HG is the second gain, and the mount gain MG is the third gain; It is noted that the design diameter is also the basic diameter of thetransducer assembly30′ as shown inFIG. 5. The units for the phase margin are Hertz, for the power dissipation are watts, for the displacement are microns (peak-to-peak), for the tissue power are watts, for the impedance are ohms, for the loaded maximum phase are degrees, for Sn−1 are Hertz, for Sn+1 are Hertz, and for Span−1 are Hertz. The above nine equations were developed for a particular example of thetransducer assembly30′ wherein a discussion of some of the characteristics of the particular transducer assembly follows. Theparticular transducer assembly30′ operated in a longitudinal mode of vibration and included a metallic end-mass component100 consisting essentially of stainless steel, a metallic transducer-horn component102 consisting essentially of titanium, and a metallic horn-mount component104 consisting essentially of titanium. The particular transducer assembly included eight PZT (piezoelectric transducer), type 8 material disks in each stack (PZT disk dimensions were: outside diameter (DD in the equations); 4.2 mm inside diameter; and 2.34 mm thick). The PZT inside diameter was 0.5 mm (millimeters) radially separated from the metal parts. The stud had 6-32 USC threads. Each half wave was tuned to a longitudinal fundamental frequency close to 55.5 KHz (kilo-Hertz). Using the above nine equations, applicants successfully built and tested a particular transducer assembly in which DD was chosen to be 8 mm.
• One technique for developing a similar set of nine equations for a different transducer assembly including, for example and without limitation, different component composition and/or a different mode (or mixed modes) of vibration and/or piezoelectric transducer disks with non-circular outer perimeters and/or a transducer assembly having a different number of half-wave sections and/or a transducer assembly having a different number of gain stages, etc., is hereinafter described. Start by selecting a statistical design such as Box-Behnken design of experiments, in which: (1) the factors (i.e., independent variables) are the design diameter of the transducer assembly, the gain stages of the transducer assembly, and the instrument gain; (2) the responses for acoustic (dynamic) performance (i.e., the acoustic-performance independent variables) are Sn+1, Sn−1, and Span−1; and (3) the responses for electromechanical performance (i.e., the electromechanical independent variables) are impedance, phase margin, tissue power, power dissipation, displacement and loaded maximum phase. Create the experiment by selecting the ranges of factors. Using commercial finite element analysis software such as Abaqus, IDEAS etc, solve cases in the experiment for finite element models of the transducer assembly. Analyze the data using commercial statistical software such as Minitab to develop the equations relating the responses to the factors. Simultaneously solve the equations to size the gain stages for delivering a desired acoustic performance with a particular attached instrument and a desired electromechanical performance with a particular connected generator. Using this methodology, a person skilled in the art can develop equations, without undue experimentation, for any transducer assembly including, for example, any fundamental vibrational mode of interest (longitudinal, torsion, bending, swelling etc.), any design cross section (including a non-circular cross section), any PZT type, any metal used for metal parts, etc. It is noted that, in a particular application, all equations of the set of nine equations would or would not be used and/or at least one different acoustic performance equation and/or different electromechanical performance equation would be included. A person skilled in the art may use different factors and responses in one or both of the electromechanical performance and the acoustic performance.
• In a first design of the second expression of the embodiment ofFIGS. 2-13, themedical ultrasound handpiece28 includes a metallic end-mass component100, a metallic transducer-horn component102, and a metallic horn-mount component104. Thepiezoelectric transducer disks42 of the first and secondstacked pluralities40 and44 ofpiezoelectric transducer disks42 are annular disks, and the transducer-horn component102 has proximal anddistal portions106 and108. Thepiezoelectric transducer disks42 of the firststacked plurality40 ofpiezoelectric transducer disks42 surround theproximal portion106 of the transducer-horn component102, and thepiezoelectric transducer disks42 of the secondstacked plurality44 ofpiezoelectric transducer disks42 surround thedistal portion108 of the transducer-horn component102.
• In one variation of the first design, the transducer-horn component102 has anintermediate portion110. Theintermediate portion110 includes thefirst gain stage46 and includes proximal anddistal seat portions112 and114 bounding thefirst gain stage46. The end-mass component100 is disposed proximal the firststacked plurality40 ofpiezoelectric transducer disks42. The end-mass component100 is threadably attached to theproximal portion106 of the transducer-horn component102 compressing the firststacked plurality40 ofpiezoelectric transducer disks42 against theproximal seat portion112. In one construction, torquing flats on the end-mass component100 and on the transducer-horn component102 facilitate such compression.
• In one modification of the first design, the horn-mount component104 is disposed distal the secondstacked plurality44 ofpiezoelectric transducer disks42. The horn-mount component104 is threadably attached to thedistal portion108 of the transducer-horn component102 compressing the secondstacked plurality44 ofpiezoelectric transducer disks42 against thedistal seat portion114. In one construction, torquing flats on the horn-mount component104 and on the transducer-horn component102 facilitate such compression. In one example, the horn-mount component104 has aproximal portion116 which includes thesecond gain stage60 and has adistal portion118 which includes thethird gain stage62.
• In one implementation of the second expression of the embodiment ofFIGS. 2-13, themedical ultrasound handpiece28 includes a housing120 (also called a mid housing), wherein thehousing120 surrounds thetransducer assembly30′. In one variation, themedical ultrasound handpiece28 includes anannular bumper assembly122 having a plurality of spaced apart and inwardly projectingbumpers124. Thebumper assembly122 surrounds the firststacked plurality40 ofpiezoelectric transducer disks42, wherein thebumpers124 are in contact with the firststacked plurality40 ofpiezoelectric transducer disks42 proximate thefirst node36, and thehousing120 is in surrounding contact with thebumper assembly122.
• In one arrangement of the second expression of the embodiment ofFIGS. 2-13, thetransducer assembly30′ has alongitudinal axis126, thehousing120 has a multi-luginward flange128, and the horn-mount component104 has a multi-lugoutward flange130 disposed proximate the third node58 (and distal the multi-luginward flange128 after first aligning the lugs for passage and then relatively rotating for non-passage). In this arrangement, thehandpiece28 includes anose cone assembly132 having a dielectric multi-lug ring134 (such as, but not limited to, a compressed, soft elastomeric, vibration isolating, multi-lug ring) disposed longitudinally between (after first aligning the lugs for passage and then relatively rotating for non-passage) and in contact with the multi-lug inward andoutward flanges128 and130 and covering and contacting the multi-lugoutward flange130. In this arrangement, thehousing120 is in surrounding contact with themulti-lug ring134.
• In one example, thenose cone assembly132 includes a longitudinally-compressed dielectric washer136 (such as, but not limited to, an elastomeric washer) distally abutting the multi-lugoutward flange130 and includes anannular nose cone138 distally abutting thewasher136. In this example, thehousing120 is in surrounding contact with thenose cone138. In one variation, thenose cone assembly132 includes first and second O-ring seals140 and142 as shown inFIGS. 3 and 9. In one modification, thenose cone assembly132 includes inner and outer conductive (electrically conductive) rings144 and146 separated by anannular dielectric member148 as shown inFIG. 9.
• In the same example, the outerconductive ring146 contacts thehousing120 and is a ground (electrical ground) ring, and the innerconductive ring144 is a hot (electrically hot) ring electrically connectable (in part by wiring150) to a low AC output of an ultrasound electric generator (not shown). Theinstrument76 has a switch (not shown) which is electrically connected to the inner and outerconductive rings144 and146 when theinstrument76 is attached to thestud74. The switch controls the ultrasound electric generator. In other arrangements, not shown, the inner and outerconductive rings144 and146 are omitted, and the ultrasound electric generator has an onboard switch or the handpiece has a switch.
• In the same example, the generator has positive and negative high AC outputs electrically connectable (in part by wiring152 and jumpers154) toelectrodes156 disposed between adjacentpiezoelectric transducer disks42. Thepiezoelectric transducer disks42 of the firststacked plurality40 ofpiezoelectric transducer disks42 are radially-inwardly electrically isolated from the transducer-horn component102 by a firstdielectric cylinder158. Thepiezoelectric transducer disks42 of the secondstacked plurality44 ofpiezoelectric transducer disks42 are radially-inwardly electrically isolated from the transducer-horn component102 by a seconddielectric cylinder160; It is noted that thestud74 extends distally of thenose cone assembly132, and that a proximal end portion of thenose cone138 is disposed inside, and press fitted to, a distal end portion of thehousing120.
• In the same example, thebumper assembly122 includespins162 from which thewiring152 extends to the electrodes/jumpers156/154 to power thepiezoelectric transducer disks42. In one variation, thehandpiece28 includes anannular end cap164 having pins (not shown) which engage thepins162 of thebumper assembly122 when a distal end portion of theend cap164 is disposed outside, and press fitted to, a proximal end portion of thehousing120. This causes thebumper assembly122 to be longitudinally secured between an inner annular seat (not shown) of thehousing120 and an inner annular seat (not shown) of theend cap164.
• In the same example, thehandpiece28 includes acable166 containing thewiring150 and thewiring152. Thecable166 extends from a proximal end portion of theend cap164 to aproximal plug168. Theplug168 is electrically connectable to an ultrasound electric generator (not shown).
• A third embodiment of the invention is shown inFIG. 15. A first expression of the embodiment ofFIG. 15 is for amedical ultrasound handpiece210 including a 1-wave medicalultrasound transducer assembly212. Thetransducer assembly212 includes consecutive first and distal-most second half-wave sections214 and216, wherein the first half-wave section214 includes afirst node218 and the second half-wave section216 includes asecond node220. The first half-wave section214 includes a firststacked plurality222 ofpiezoelectric transducer disks224 and the second half-wave section216 includes a secondstacked plurality226 ofpiezoelectric transducer disks224. Thetransducer assembly212 includes first and second gain stages228 and230, wherein thefirst gain stage228 is located in the first half-wave section214 distal the firststacked plurality222 ofpiezoelectric transducer disks224, and wherein thesecond gain stage230 is located in the second half-wave section216 distal the secondstacked plurality226 ofpiezoelectric transducer disks224.
• In one enablement of the first expression of the embodiment ofFIG. 15, the second half-wave section216 distally terminates in astud232 which is attachable to an ultrasonically-vibratable medical-treatment instrument234. In one variation, thestud232 includes a proximal threadedportion242 and includes a distalnon-threaded portion244 adjoining the proximal threadedportion242, wherein the proximal threadedportion242 is threadably attachable to theinstrument234. Examples of non-stud and/or non-threadable attachments are left to those skilled in the art. A method for tuning thehandpiece210 is identical to the previously described method for tuning thehandpiece28.
• In one arrangement of the first expression of the embodiment ofFIG. 15, the firststacked plurality222 ofpiezoelectric transducer disks224 is substantially centered about thefirst node218, and the secondstacked plurality226 ofpiezoelectric transducer disks224 is disposed proximal thesecond node220. In one variation, thefirst gain stage228 has aproximal end236 which is distally spaced apart from the firststacked plurality222 ofpiezoelectric transducer disks224 and has adistal end238 which is disposed proximate acommon antinode240 of the first and second half-wave sections214 and216. In one example, thefirst gain stage228 includes astacked plurality246 ofpiezoelectric transducer disks224′. In another example, not shown, the first gain stage lacks any piezoelectric transducer disks. It is noted that anoperating handpiece210 will have a proximal antinode at the proximal end of thetransducer assembly212 and a distal antinode at the distal end of thetransducer assembly212.
• A fourth embodiment of the invention is shown inFIG. 16. A first expression of the embodiment ofFIG. 16 is for amedical ultrasound handpiece310 including a ½-wave medicalultrasound transducer assembly312. Thetransducer assembly312 includes aproximal antinode314, adistal antinode316, and anode318 located between the proximal anddistal antinodes314 and316. Thetransducer assembly312 includes a firststacked plurality320 of piezoelectric transducer disks322 located proximal thenode318, a secondstacked plurality324 of piezoelectric transducer disks322′ located distal thenode318, and again stage326 located distal the secondstacked plurality324 of piezoelectric transducer disks322′.
• In one enablement of the first expression of the embodiment ofFIG. 16, thetransducer assembly312 distally terminates in astud328 which is attachable to an ultrasonically-vibratable medical-treatment instrument330. In one variation, thestud328 includes a proximal threadedportion332 and includes a distalnon-threaded portion334 adjoining the proximal threadedportion332, wherein the proximal threadedportion332 is threadably attachable to theinstrument330. Examples of non-stud and/or non-threadable attachments are left to those skilled in the art. A method for tuning thehandpiece310 is identical to the previously described method for tuning thehandpiece28.
• A fifth embodiment of the invention is shown inFIG. 17. A first expression of the embodiment ofFIG. 17 is for amedical ultrasound system410 including a medicalultrasound transducer assembly412 and an ultrasonically-vibratable medical-treatment instrument414. Thetransducer assembly412 has a gain of unity and has adistal end portion418. Theinstrument414 is attachable (and in one example is attached) to thedistal end portion418 of thetransducer assembly412 and has at least onegain stage420,422,424 and426.
• In one enablement of the first expression of the embodiment ofFIG. 17, the at-least-onegain stage420,422,424 and426 includes a plurality of gain stages420,422,424 and426. In one variation, eachgain stage420,422,424 and426 has aproximal end428 disposed proximate acorresponding node430 of theinstrument414 and has adistal end432 disposed proximate acorresponding antinode434 of the instrument to maximize the displacement at thedistal end436 of theinstrument414. In one implementation of the embodiment ofFIG. 17, thetransducer assembly412 includes astacked plurality438 ofpiezoelectric transducer disks440. In one example, the (unity gain)transducer assembly412 should have less quiescent power and heat than a high gain transducer assembly and should provide for better sealing (because of less nodal vibration) than a high gain transducer assembly. In the same or a different example, the (unity gain)transducer assembly412 should provide for asmaller handpiece412 and should provide the potential for quick connection of an instrument414 (such as a scalpel) to thehandpiece412.
• A sixth embodiment of the invention is shown inFIG. 18. A first expression of the embodiment ofFIG. 16 is for amedical ultrasound system442 including a medicalultrasound transducer assembly444 and an ultrasonically-vibratable medical-treatment instrument446. Thetransducer assembly444 has adistal end portion450. Theinstrument446 is attachable (and in one example is attached) to thedistal end portion450 of thetransducer assembly444. Thetransducer assembly444 and the attachedinstrument446 together have an operating wavelength. Thetransducer assembly444 alone has a length which is at least equal to ¼ of the operating wavelength and which is less than ½ of the operating wavelength. Thetransducer assembly444 and the attachedinstrument446 together have a length equal to N times ½ of the operating wavelength, wherein N is a non-zero positive whole number.
• In one enablement of the first expression of the embodiment ofFIG. 18, N equals one. In one variation, thetransducer assembly444 and the attachedinstrument446 together have anode452, and thetransducer assembly444 includes thenode452. In one modification, thetransducer assembly444 includes astacked plurality454 ofpiezoelectric transducer disks456. In one example, thetransducer assembly444 includes aflange458 disposed proximate thenode452. In a first construction, theflange458 is disposed proximal thenode452 with theinstrument446 attached to theflange458 and with thestacked plurality454 ofpiezoelectric transducer disks456 disposed proximal and abutting theflange458.
• In a second construction, as shown in alternate embodiment ofFIG. 19, theflange460 of thetransducer assembly462 is disposed distal thenode464 with theinstrument466 attached to theflange460 and with thestacked plurality468 ofpiezoelectric transducer disks470 disposed proximal and abutting theflange460. In a third construction, as shown in the alternate embodiment ofFIG. 20, theflange472 of thetransducer assembly474 is substantially centered at thenode476 with theinstrument478 attached to theflange472, with thestacked plurality480 ofpiezoelectric transducer disks482 disposed proximal and abutting theflange472, and with an additionalstacked plurality484 ofpiezoelectric transducer disks482 disposed distal and abutting theflange472.
• A seventh embodiment of the invention is shown inFIG. 21. A first expression of the embodiment ofFIG. 21 is for amedical ultrasound handpiece510 including a medicalultrasound transducer assembly512. Thetransducer assembly512 has proximal anddistal nodes514 and516. Thetransducer assembly512 has a first transducer-assembly-to-housing mounting feature518 disposed proximate theproximal node514 and a second transducer-assembly-to-housing mounting feature520 disposed proximate thedistal node516. Thetransducer assembly512 lacks any additional transducer-assembly-to-housing mounting feature.
• In one enablement of the first expression of the embodiment ofFIG. 21, thehandpiece510 includes ahousing522 having anopening524 and surrounding thetransducer assembly512, wherein thetransducer assembly512 is insertable into thehousing522 through theopening524. In one variation, thetransducer assembly512 includes astacked plurality526 ofpiezoelectric transducer disks528. In a first example, the first transducer-assembly-to-housing mounting feature518 is a first outward flange of thetransducer assembly512, and the second transducer-assembly-to-housing mounting feature520 is second outward flange of thetransducer assembly512, wherein the first outward flange projects more (or less) than the second outward flange.
• In a second example, as shown in the alternate embodiment ofFIG. 22, the first transducer-assembly-to-housing mounting feature530 is an outward flange of thetransducer assembly532, and the second transducer-assembly-to-housing mounting feature534 is an O-ring groove of thetransducer assembly532. The outward flange projects more (or less) than an O-ring (not shown) disposed in the O-ring groove.
• In a third example, as shown in the alternate embodiment ofFIG. 23, the first transducer-assembly-to-housing mounting feature536 is an O-ring groove of thetransducer assembly538, and the second transducer-assembly-to-housing mounting feature540 is an outward flange of thetransducer assembly538. An O-ring (not shown) disposed in the O-ring groove projects more (or less) than the outward flange.
• In a fourth example, as shown in the alternate embodiment ofFIG. 24, the first transducer-assembly-to-housing mounting feature542 is a first O-ring groove of thetransducer assembly544, and the second transducer-assembly-to-housing mounting feature546 is second O-ring groove of thetransducer assembly544. A first O-ring (not shown) disposed in the first O-ring groove projects more (or less) than a second O-ring (not shown) disposed in the second O-ring groove.
• In a fifth example, as shown in the alternate embodiment ofFIG. 25, the first transducer-assembly-to-housing mounting feature548 is a first pair of O-ring-bounding outward flanges of thetransducer assembly550, and the second transducer-assembly-to-housing mounting feature552 is a second pair of O-ring-bounding outward flanges of thetransducer assembly550. A first O-ring (not shown) bounded by the first pair of O-ring-bounding outward flanges projects more (or less) than a second O-ring (not shown) bounded by the second pair of O-ring-bounding outward flanges.
• An eighth embodiment of the invention is shown inFIGS. 26-29. A first expression of the embodiment ofFIGS. 26-29 is for amedical ultrasound handpiece610 including a medicalultrasound transducer assembly612 and an annular connector assembly614 (which is also called an annular bumper assembly). Thetransducer assembly612 includes a metallic end-mass component616, apiezoelectric transducer disk618, and anelectrode620. Thepiezoelectric transducer disk618 is located distal the end-mass component616 and is in electrical contact with theelectrode620. Theconnector assembly614 surrounds thetransducer assembly612, is in electrical contact (such as at least in part by wiring623) with theelectrode620, and is electrically connectable to an ultrasoundelectric generator622.
• In one enablement of the first expression of the embodiment ofFIGS. 26-29, themedical ultrasound handpiece610 includes anelectric cable624 and acable socket626, wherein thecable624 has aproximal end628 electrically connectable to the ultrasoundelectric generator622 and has adistal end630 electrically connected to thecable socket626, and wherein the end-mass component616 is disposable within thecable socket626. In one variation, thecable socket626 has connector pins632, and theconnector assembly614 has connector pins634 which are engagable with the connector pins632 of thecable socket626. In one modification, thehandpiece610 includes anend cap636, wherein thecable socket626 is disposable in theend cap636. In one example, thehandpiece610 includes ahousing638, wherein thehousing638 surrounds theconnector assembly614 and has aproximal end portion640, and wherein theend cap636 has adistal end portion642 which is press-fittingly attachable to theproximal end portion640 of thehousing638.
• A second expression of the embodiment ofFIGS. 26-29 is for amedical ultrasound handpiece610 including a medicalultrasound transducer assembly612 and anannular connector assembly614. Thetransducer assembly612 includes a metallic end-mass component616, astacked plurality644 ofpiezoelectric transducer disks618, andelectrodes620. Thestacked plurality644 ofpiezoelectric transducer disks618 is located distal the end-mass component616. Eachpiezoelectric transducer disk618 is in electrical contact with acorresponding electrode620. Theconnector assembly614 surrounds thetransducer assembly612, is in electrical contact (such as at least in part by wiring623) with theelectrodes620, and is electrically connected to acable socket626 which is electrically connectable to an ultrasoundelectric generator622.
• It is noted that inFIG. 27, the left-most of the two shownpiezoelectric transducer disks618 is in electrical contact with the left-most (but not the right-most) of the two shownelectrodes620 and the right-most of the two shownpiezoelectric transducer disks618 is in electrical contact with the right-most (but not the left-most) of the two shownelectrodes620.
• In one enablement of the second expression of the embodiment ofFIGS. 26-29, themedical ultrasound handpiece610 includes anelectric cable624, wherein thecable624 has aproximal end628 electrically connectable to thegenerator622 and has adistal end630 electrically connected to thecable socket626, and wherein the end-mass component616 is disposed within thecable socket626. In one variation, thecable socket626 has connector pins632, and theconnector assembly614 has connector pins634 which are engaged with the connector pins632 of thecable socket626. In one modification, thehandpiece610 includes anend cap636, wherein thecable socket626 is disposed in theend cap636. In one example, thehandpiece610 includes ahousing638, wherein thehousing638 surrounds theconnector assembly614 and has aproximal end portion640, and wherein theend cap636 has adistal end portion642 which is press-fittingly attached to theproximal end portion640 of thehousing638.
• A ninth embodiment of the invention is shown inFIGS. 30-32. A first expression of the embodiment ofFIGS. 30-32 is for amedical ultrasound handpiece710 including a medicalultrasound transducer assembly712, an innerconductive ring714, and an outerconductive ring716. Thetransducer assembly712 is electrically connectable to an ultrasoundelectric generator718, has alongitudinal axis720, and is attachable to an ultrasonically-vibratable medical-treatment instrument722 having aswitch744 which has an open position and a closed position. The innerconductive ring714 is substantially coaxially aligned with thelongitudinal axis720, surrounds thetransducer assembly712, and has a distally-facing firstannular surface746. The outerconductive ring716 is substantially coaxially aligned with thelongitudinal axis720, surrounds thetransducer assembly712, and has a distally-facing secondannular surface748. The outerconductive ring716 is electrically isolated from the innerconductive ring714. The first and secondannular surfaces746 and748 are in electric contact with theswitch744 of the attachedinstrument722 when theswitch744 is in the closed position. The inner and outerconductive rings714 and716 are electrically connectable to thegenerator718, and theswitch744 of the attachedinstrument722 controls theconnected generator718.
• In one enablement of the first expression of the embodiment ofFIGS. 30-32, thetransducer assembly712 is attached to theinstrument722. In one variation, thetransducer assembly712 distally terminates in astud750 which is attachable to theinstrument722. In one modification, thestud750 is threadably attachable to theinstrument722.
• In one implementation of the first expression of the embodiment ofFIGS. 30-32, thehandpiece710 includes anannular dielectric member758, wherein the inner and outerconductive rings714 and716 are separated by thedielectric member758. In one the inner and outerconductive rings714 and716 are electrically connected to thegenerator718. In one variation, anelectric cable752 extends from thehandpiece710 to aproximal plug754 which is attachable to thegenerator718, andwiring756 extends from thecable752 within thehandpiece710 to thetransducer assembly712, to the innerconductive ring714, and to the outerconductive ring716. In an alternate variation, not shown, wiring does not extend directly from the cable to the outer conductive ring but extends to the housing which electrically contacts the outer conductive ring, wherein the housing serves as electrical ground. In one example, thetransducer assembly712 is attached to theinstrument722.
• In one construction of the first expression of the embodiment ofFIGS. 30-32, closing theswitch744 causes afirst switch pin760 to electrically contact the innerconductive ring714 and causes asecond switch pin762 to electrically contact the outerconductive ring716. In the same or a different construction, thehandpiece710 includes ahousing764 and anose cone assembly766, wherein thenose cone assembly766 is attached to thehousing764 and includes the innerconductive ring714, the outerconductive ring716, and thedielectric member758. In one modification, mounts768 disposed at nodes of thetransducer assembly712 secure thetransducer assembly712 within and to thehousing764, wherein themounts768 have openings to pass the wiring756 from thecable752 to the inner and outerconductive rings714 and716.
• In one application of the first expression of the embodiment ofFIGS. 30-32, theinstrument722 has an ultrasonicallyvibratable portion770 which is attachable to thestud750 and has a surroundingnon-vibratable portion772. Thenon-vibratable portion772 surrounds thevibratable portion770 and includes theswitch744. In one variation, theswitch744 is a two button switch (such as that described in US Patent Application Publications 2004/0147947 and 2002/0057541). In another variation, not shown, the switch is a one button switch. Other designs of the switch and modes of generator control by the switch, are left to those skilled in the art.
• A tenth embodiment of the invention is shown inFIGS. 33-35. A first expression of the embodiment ofFIGS. 33-35 is for amedical ultrasound handpiece810 including a medicalultrasound transducer assembly812, ahousing814, amount816, and anannular bumper unit818. Thehousing814 surrounds thetransducer assembly812. Themount816 pivotally attaches thetransducer assembly812 to thehousing814. Thebumper unit818 is attached to thehousing814 and includes a plurality of spaced apart and inwardly projectingbumpers820. None of thebumpers820 is in contact with thetransducer assembly812 when thetransducer assembly812 is not under a pivoting load (as shown inFIG. 34). At least one of thebumpers820 is contact with thetransducer assembly812 when thetransducer assembly812 is under the pivoting load (as shown inFIG. 35).
• A pivoting load is a load which causes thetransducer assembly812 to pivot about themount816 with respect to thehousing814. In one application, thetransducer assembly812 distally terminates in astud822, and an ultrasonically-vibratable medical-treatment instrument (not shown) is attachable to thestud822. In one example, a pivoting load is produced when a surgeon holds thehousing814 and presses down on patient tissue with the distal end of the attached instrument which causes a thetransducer assembly812 to pivot about themount816 with respect to thehousing814 and causes thetransducer assembly812 proximal themount816 to contact at least one of thebumpers820 as shown inFIG. 35. It is noted that a small area of contact of thetransducer assembly812 with thebumpers820 should reduce damping and power loss.
• In one construction of the first expression of the embodiment ofFIGS. 33-35, themount816 includes an elastomeric ring. Other constructions and types of mounts are left to the artisan.
• In one enablement of the first expression of the embodiment ofFIGS. 33-35, thetransducer assembly812 has adistal-most node826, and themount816 is in contact with thetransducer assembly812 proximate thedistal-most node826. In one variation, thetransducer assembly812 has aproximal-most node828, and thebumper unit818 is disposed proximate theproximal-most node828. In one example, thebumper unit818 is press-fittingly attached to thehousing814. In one illustration, thetransducer assembly812 is a 1½-wave transducer assembly.
• An eleventh embodiment of the invention is shown inFIGS. 36-42. A first expression of the embodiment ofFIGS. 36-42 is for amedical ultrasound handpiece910 including a medicalultrasound transducer assembly912, at least one mountingmember914, and afirst housing component916. Thetransducer assembly912 has alongitudinal axis918 and has a substantially coaxially aligned,circumferential surface groove920. The at-least-one mounting member914 is at-least-partially-annular and has aninner portion922 located in thesurface groove920. Thefirst housing component916 surrounds thetransducer assembly912 and has adistal end portion924 including an annular longitudinally-facingsurface926 with a recessedseat928. The at-least-one mounting member914 has at least aproximal portion930 located in theseat928.
• In a first construction of the first expression of the embodiment ofFIGS. 36-42, the at-least-one mounting member914 is a partially annular monolithic mounting member. In a second construction, not shown, the at-least-one mounting member includes a plurality (such as two) mounting members disposed in a partially annular array. In one choice of materials, the at-least-one mounting member914 is dielectric (or at least theinner portion922 is dielectric or coated with a dielectric material) to electrically isolate thedistal end portion924 of thefirst housing component916 from thesurface groove920 of thetransducer assembly912. In one example, the at-least-one mounting member914 is elastomeric. In one employment, the gap, when the at-least-one mounting member914 has a partially-annular construction, allows for the passage of wiring (not shown). Other constructions, including fully annular constructions, are left to the artisan.
• In one enablement of the first expression of the embodiment ofFIGS. 36-42, thehandpiece910 includes asecond housing component932 surrounding thetransducer assembly912 and having aproximal end portion934 which surrounds and is attached to thedistal end portion924 of thefirst housing component916. In one variation, theproximal end portion934 of thesecond housing component932 includes an internalannular ledge936 which seats against adistal portion938 of the at-least-one mounting member914. In one variation, theproximal end portion934 of thesecond housing component932 is press-fittingly attached to thedistal end portion924 of thefirst housing component916. In one example, thetransducer assembly912 has adistal-most node940, and thesurface groove920 is disposed proximate thedistal-most node940.
• In one employment of the first expression of the embodiment ofFIGS. 36-42, thefirst housing component916 is referred to as the housing and thesecond housing component932 is referred to as the nose cone. It is noted that in schematicFIG. 37, thetransducer assembly912 is shown withjumpers942, wherein jumpers have been discussed in one or more previous embodiments.
• In a first method of assembly of thehandpiece910, the proximal end (the left end inFIG. 37) of thetransducer assembly912 is not conventionally inserted into the distal end opening (the right end opening inFIG. 37) of thefirst housing component916 wherein the protrudingjumpers942 and wiring (not shown) at the stacked plurality or (stacked pluralities) of piezoelectric transducer disks (not shown) of thetransducer assembly912 have to be fished through the narrow distal end opening. Rather, by making the at-least-one mounting member914 be a separate piece (or separate pieces) from thetransducer assembly912 and act as a conventional transducer assembly mounting flange, the distal end (the right end inFIG. 37) of thetransducer assembly912 is inserted in the proximal end opening (the left end opening inFIG. 37) of thefirst housing component916, and pushed to the position shown inFIG. 38 exposing thesurface groove920 of thetransducer assembly912 beyond the distal end (the right end inFIG. 38) of thefirst housing component916.
• Continuing with the assembly, then the at least-one-mountingmember914 is installed in thesurface groove920 as shown inFIG. 39. Then, thetransducer assembly912 is moved proximally within thefirst housing component916 to seat theproximal portion930 of the at least-one-mountingmember914 within the recessedseat928 of the longitudinally-facingsurface926 of thedistal end portion924 of thefirst housing component916 as shown inFIG. 40. Then, theproximal end portion934 of thesecond housing component932 is press fittingly attached to thedistal end portion924 of thefirst housing component916 as shown inFIG. 36.
• In one arrangement of the first expression of the embodiment ofFIGS. 36-42, the at-least-one mounting member914 has at least one peripheral flat944 which engages a corresponding at least one peripheral flat946 on the recessedseat928 of the longitudinally-facingsurface926 of thedistal end portion924 of thefirst housing component916. This prevents rotation of the at-least-one mounting member914. In the same or a different arrangement, the at-least-one mounting member914 is flexible (i.e., can be flexed by an adult person of average strength) to facilitate installation.
• Several benefits and advantages are obtained from one or more of the expressions of embodiments of the invention. In one example, one or more or all of the expressions of embodiments of the invention help enable a relatively small size medical ultrasound transducer assembly to provide an attached ultrasonically-vibratable medical-treatment instrument with a desirable high displacement (i.e., a large vibrational amplitude) resulting in a relatively small size handpiece which is suitable for a surgeon to hold and use in precise and delicate surgery.
• While the present invention has been illustrated by a description of several expressions, embodiments, and examples, etc. thereof, it is not the intention of the applicants to restrict or limit the spirit and scope of the appended claims to such detail. Numerous other variations, changes, and substitutions will occur to those skilled in the art without departing from the scope of the invention. It will be understood that the foregoing description is provided by way of example, and that other modifications may occur to those skilled in the art without departing from the scope and spirit of the appended Claims.

Claims (16)

1-50. (canceled)

51. A medical ultrasound handpiece comprising:

a) a medical ultrasound transducer assembly which is electrically connectable to an ultrasound electric generator, which has a longitudinal axis, and which is attachable to an ultrasonically-vibratable medical-treatment instrument having a switch which has an open position and a closed position;

b) an inner conductive ring substantially coaxially aligned with the longitudinal axis, surrounding the transducer assembly, and having a distally-facing first annular surface; and

c) an outer conductive ring substantially coaxially aligned with the longitudinal axis, surrounding the transducer assembly, and having a distally-facing second annular surface, wherein the outer conductive ring is electrically isolated from the inner conductive ring, wherein the first and second annular surfaces are in electric contact with the switch of the attached instrument when the switch is in the closed position, wherein the inner and outer conductive rings are electrically connectable to the generator, and wherein the switch of the attached instrument controls the connected generator.

52. The medical ultrasound handpiece ofclaim 51, wherein the transducer assembly is attached to the instrument.

53. The medical ultrasound handpiece ofclaim 51, also including an annular dielectric member, wherein the inner and outer conductive rings are separated by the dielectric member.

54. The medical ultrasound handpiece ofclaim 53, wherein the first and second rings are electrically connected to the generator.

55. The medical ultrasound handpiece ofclaim 54, wherein the transducer assembly is attached to the instrument.

56-65. (canceled)

66. The medical ultrasound handpiece ofclaim 51, wherein the transducer assembly distally terminates in a stud which is attachable to the instrument.

67. The medical ultrasound handpiece ofclaim 66, wherein the stud is threadably attachable to the instrument.

68. The medical ultrasound handpiece ofclaim 67, wherein the instrument has an ultrasonically vibratable portion which is attachable to the stud and has a surrounding non-vibratable portion.

69. The medical ultrasound handpiece ofclaim 68, wherein the non-vibratable portion includes the switch.

70. The medical ultrasound handpiece ofclaim 51, also including an annular dielectric member, wherein the inner and outer conductive rings are separated by the dielectric member.

71. The medical ultrasound handpiece ofclaim 70, also including a housing and a nose cone assembly, wherein the nose cone assembly is attached to the housing and includes the inner conductive ring, the outer conductive ring, and the dielectric member.

72. The medical ultrasound handpiece ofclaim 71, also including mounts which are disposed at nodes of the transducer assembly and which secure the transducer assembly within and to the housing.

73. The medical ultrasound handpiece ofclaim 72, also including an electric cable and wiring, wherein the electric cable extends from the handpiece to a proximal plug which is attachable to the generator, and wherein the wiring extends from the cable to the inner conductive ring.

74. The medical ultrasound handpiece ofclaim 73, wherein the mounts have openings to pass the wiring from the cable to the inner conductive ring.

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