Chucks for wire drives

Abstract

The chuck (10) includes a jaw guide (64), staggered jaws (66) and an inclined engagement surface (84). The jaw guide defines a longitudinal axis (24) and includes a jaw channel (65) distributed circumferentially around the axis. The jaws are slidably arranged in the jaw channel. Each jaw has a clamping surface (88) facing the axis and a drive surface (90) substantially opposite the clamping surface, and has a protrusion (92) on a first lateral side and a cavity (96) on a second lateral side. The protrusion of each jaw is at least partially arranged in the cavity of an adjacent jaw. The engagement surface is located on one of the inner surface of the jaw guide and the engagement sleeve (80) and is substantially centered on the axis and substantially parallel to the drive surface. Displacement of the jaw relative to the engagement surface in a clamping direction causes the clamping surface to shift toward the axis.

Description

[0001] Related Applications

[0002] This patent application claims priority to and all the benefits of U.S. Provisional Patent Application No. 62 / 862,854 filed on June 18, 2019 and U.S. Provisional Patent Application No. 62 / 740,579 filed on October 3, 2018, both of which are hereby incorporated by reference in their entirety. Background Art

[0003] Inserting and clamping a shaft (e.g., wire, pin, drill bit) into a three-jaw chuck so that it is centered about the axis of rotation and securely held in the chuck can be difficult, particularly when the chuck is used to selectively clamp and release and hold the shaft. A shaft at the lower end of the chuck's diameter range can be accidentally inserted and clamped off-center or at an angle to the axis of rotation. BRIEF DESCRIPTION OF THE DRAWINGS

[0004] Figure 1 is a top, front, right side perspective view of an example chuck coupled to an example handpiece.

[0005] Figure 2 yes Figure 1 A top right rear perspective view of the chuck and handpiece.

[0006] Figure 3 yes Figure 1 Right side view of an example chuck.

[0007] Figure 4 yes Figure 1 A top view of an example chuck.

[0008] Figure 5A It is intercepted along the direction of arrow 5 Figure 4 A cross-sectional view of the chuck.

[0009] Figure 5B is one of the Figure 5A A cross-sectional view of the chuck.

[0010] Figure 5C is one with a second axis Figure 5A A cross-sectional view of the chuck.

[0011] Figure 6 yes Figure 1-5C Exploded view of the chuck.

[0012] Fig. 7A yes Figure 1-6 A left side view of the chuck jaws of a first example of a chuck.

[0013] Figure 7B yes Fig. 7AFront view of the chuck jaws.

[0014] Figure 7C yes Fig. 7A Right side view of the chuck jaws.

[0015] Fig. 8A is in the pre-clamped position relative to the example small diameter shaft Figures 7A-7C A top left rear perspective view of three of the chuck jaws.

[0016] Figure 8B is in the pre-clamped position relative to the example small diameter shaft Fig. 8A A top right front perspective view of three of the chuck jaws.

[0017] Figure 8C is in the pre-clamped position relative to the example small diameter shaft Fig. 8A Front view of the chuck jaws.

[0018] Fig.8D is in the clamped position relative to the example large diameter shaft Fig. 8A Front view of the chuck jaws.

[0019] Fig.9A yes Figure 1-6 A left side view of the chuck jaws of a second example of a chuck.

[0020] Fig. 9B yes Fig.9A Front view of the chuck jaws.

[0021] Fig. 9C yes Fig.9A Right side view of the chuck jaws.

[0022] Fig. 10A is in the pre-clamped position relative to the example small diameter shaft Fig.9A A top left rear perspective view of three of the chuck jaws.

[0023] Fig. 10B is in the pre-clamped position relative to the example small diameter shaft Fig. 10A A top right front perspective view of three of the chuck jaws.

[0024] Fig. 10C is in the pre-clamped position relative to the example small diameter shaft Fig. 10A Front view of the chuck jaws.

[0025] Fig. 10D is in the clamped position relative to the example large diameter shaft Fig. 10A Front view of the chuck jaws.

[0026] Fig.11A yes Figure 1-6A left side view of the chuck jaws of a third example of a chuck.

[0027] Fig. 11B yes Fig.11A Front view of the chuck jaws.

[0028] Fig. 11C yes Fig.11A Right side view of the chuck jaws.

[0029] Fig. 12A is in the pre-clamped position relative to the example small diameter shaft Fig.11A A top left rear perspective view of three of the chuck jaws.

[0030] Fig. 12B is in the pre-clamped position relative to the example small diameter shaft Fig. 12A A top right front perspective view of three of the chuck jaws.

[0031] Fig. 12C is in the pre-clamped position relative to the example small diameter shaft Fig. 12A Front view of the chuck jaws.

[0032] Fig.12D is in the clamped position relative to the example large diameter shaft Fig. 12A Front view of the chuck jaws.

[0033] Fig.13A yes Fig.14 and Fig.15 A second example of a chuck is shown in right side view of the chuck jaws.

[0034] Fig. 13B yes Fig.13A Rear view of the chuck jaws.

[0035] Fig. 13C yes Fig.13A Left side view of the chuck jaws.

[0036] Fig.14 is along Fig.15 A cross-sectional view of a first alternative chuck configuration is taken in the direction of arrow 14 .

[0037] Fig.15 It is taken along the direction of arrow 15 Fig.14 A cross-sectional view of the chuck.

[0038] Fig.16 is along Fig.17 A cross-sectional view of a second alternative chuck configuration taken in the direction of arrow 16 .

[0039] Fig.17 It is taken along the direction of arrow 17 Fig.16 A cross-sectional view of the chuck.

[0040] Fig.18A It is mainly from Fig.16 and Fig.17 The right side of the jaw is seen in a perspective view looking up at the right front side.

[0041] Fig.18B It is mainly from Fig.18A The bottom of the jaw is seen in a front right perspective view looking up.

[0042] Fig.19A is in open state Fig.16 A top right front perspective view of the split nut and jaws of the chuck with a small diameter wire arranged therein.

[0043] Fig.19B In clamping condition Fig.19A A front cross-sectional view of a split nut and jaw through plane 19B, wherein a small diameter wire is arranged.

[0044] Fig.19C In clamping condition Fig.19A A front cross-sectional view of a split nut and jaw through plane 19B, wherein a large diameter wire is arranged. DETAILED DESCRIPTION

[0045] The prior art does not address the need to quickly and easily insert and clamp a shaft into a jaw chuck, which may be required for use during a surgical procedure.

[0046] An example chuck includes a jaw guide, a plurality of staggered jaws, and an inclined engagement surface. The jaw guide defines a longitudinal axis and includes a jaw channel distributed circumferentially around the axis. The jaw is slidably disposed in the jaw channel. Each jaw has a clamping surface facing the axis and a drive surface substantially opposite the clamping surface, and has a protrusion on a first side and a cavity on a second side. The protrusion of each jaw is at least partially arranged in the cavity of an adjacent jaw. The engagement surface is located on one of the inner surface of the jaw guide and the engagement sleeve, and is substantially centered on the axis and substantially parallel to the drive surface. Displacement of the jaw relative to the engagement surface in a clamping direction causes the clamping surface to shift toward the axis.

[0047] The chuck for wire drive comprises an axially extending jaw guide, a plurality of staggered jaws and an engagement sleeve. The axially extending jaw guide defines a longitudinal axis and comprises a plurality of first jaw channels circumferentially distributed around the axis. A plurality of staggered jaws are slidably arranged in the jaw channel. Each jaw has a clamping surface facing the axis and a driving surface substantially opposite to the clamping surface, and has a projection on a first side and a cavity on a second side. The projection of each jaw is at least partially arranged in the cavity of adjacent jaws. The engagement sleeve has an inclined engagement surface on its inner surface. The engagement surface is substantially centered on the axis and substantially parallel to the driving surface. The displacement of the jaw guide relative to the engagement sleeve in the clamping direction causes the clamping surface to shift toward the axis.

[0048] Such a chuck may include additional features as described below, which features are included alone or in combination with one another, such combinations being limited only by mutual exclusivity.

[0049] The jaws may define a receiving aperture adapted to receive and clamp a shaft from a first diameter to a second, larger diameter, and the projection is disposed in the cavity when the jaws are positioned to clamp a shaft having the first diameter.

[0050] The channels and jaws may be evenly distributed about the axis, with the protrusion of each jaw being substantially complementary to the cavity in an adjacent jaw.

[0051] The jaws may have a protrusion or a cavity on each of the first side and the second side, and the protrusion of the first side of each jaw may be at least partially arranged in the cavity of the second side of the adjacent jaw. The protrusion of the second side of each jaw may be at least partially arranged in the cavity of the first side of the adjacent jaw.

[0052] The jaws and the projections may each have an inclined distal surface that is shorter at the clamping surface.

[0053] The jaws and projections may each have an inclined proximal surface that is shorter at the clamping surface.

[0054] The jaw and the projection may each have an inclined distal surface that is shorter at the clamping surface, and an inclined proximal surface that is shorter at the clamping surface.

[0055] The protrusion may extend into a gap between opposing sides of adjacent jaws adjacent the clamping surface.

[0056] The protrusion may extend beyond the clamping surface towards the axis.

[0057] The chuck may further include a generally cylindrical housing and a clamping rod. The jaw guide, the jaw and the engagement sleeve may be rotatably arranged inside the generally cylindrical housing. The clamping rod may be pivotally mounted to the housing and connected to one of the jaw guide and the engagement sleeve for axial displacement thereof.

[0058] The chuck has a ratio of the largest axis to the smallest axis that can be accommodated by the chuck without pinching that is substantially equal to 4:1.

[0059] The chuck may further include a generally cylindrical housing and a clamping rod. The jaw guide, the jaw and the engagement sleeve may be rotatably arranged inside the generally cylindrical housing. The clamping rod may be pivotally mounted to the housing and connected to one of the jaw guide and the engagement sleeve to axially displace the engagement sleeve.

[0060] The inclined engagement surface may be located on the engagement sleeve. The jaw guide may be substantially fixed relative to the engagement sleeve. The chuck may further include an axially displaceable actuating head axially engaged with the jaw. Axial displacement of the actuating head in the engagement direction may push the drive surface of the jaw against the inclined engagement surface and axially displace the jaw relative to the engagement sleeve.

[0061] The inclined engagement surface may be located on the jaw guide.The jaw may have a threaded surface disposed thereon that threadably engages with a thread disposed on the sleeve.

[0062] The jaw guide may be at the distal end of the drive shaft.

[0063] The chuck for wire drive comprises a generally cylindrical housing, an axially extending drive shaft, a plurality of jaws, an engagement sleeve, an actuator sleeve, a first locating bearing, a second locating bearing and a clamping actuator. The generally cylindrical housing defines a longitudinal axis. The axially extending drive shaft is rotatably arranged in the housing on the longitudinal axis to selectively rotate around the longitudinal axis. The drive shaft comprises a jaw guide at the distal end of the drive shaft. The jaw guide comprises a plurality of first jaw channels circumferentially distributed around the axis. A plurality of jaws are slidably arranged in the jaw channel. Each jaw has a clamping surface facing the axis and a driving surface substantially opposite to the clamping surface. The engagement sleeve is rotatably arranged in the housing on the longitudinal axis to selectively rotate around the longitudinal axis. The engagement sleeve has an inclined engagement surface on its inner surface. The engagement surface is substantially centered on the axis and substantially parallel to the driving surface. The engagement surface is at least partially arranged to be axially aligned with the drive surface and is arranged radially outside thereof, and selectively engages with the drive surface. The actuator sleeve is slidably and non-rotatably arranged on the longitudinal axis, near the engagement surface, and selectively axially engages with the engagement sleeve in each of the first axial direction and the second axial direction. The first locating bearing is an axial-radial bearing arranged between the drive shaft and the housing near the actuator sleeve. The second locating bearing is a substantially radially bearing-only bearing arranged between the engagement sleeve and the housing at the far side of the actuator sleeve. The clamping actuator is connected to the actuator sleeve by a clamping linkage device to axially displace the engagement sleeve. The displacement of the engagement sleeve relative to the jaw guide in the clamping direction displaces the clamping surface toward the axis.

[0064] The chuck of the preceding paragraph may include additional features as described below, which features may be included alone or in combination with one another, such combinations being limited only by mutual exclusivity.

[0065] The chuck may further comprise a bearing support sleeve arranged on and fixed to the drive shaft, wherein the inner race of the first locating bearing is fixed to the bearing support sleeve.

[0066] The bearing support sleeve may include threads on its inner diameter and a first shoulder on the inner diameter at the proximal end of the threads. The drive shaft may include threads on the tail portion of the drive shaft and a second shoulder on the outer diameter of the drive shaft at the proximal end of the threads. The threads of the bearing support sleeve may be threadedly engaged with the threads of the tail portion, and the corresponding shoulders may engage with each other.

[0067] The clamping actuator may include a clamping rod pivotally mounted to the housing. The clamping linkage may include a yoke portion of the rod engaging the actuator sleeve. Displacement of the engagement sleeve relative to the jaw guide in the clamping direction may displace the clamping surface toward the axis.

[0068] A first thrust bearing may be disposed between the distal end of the actuator sleeve and the engagement sleeve. A second thrust bearing may be disposed between the proximal end of the actuator sleeve and the engagement sleeve.

[0069] Relative orientations and directions (e.g., top, bottom, bottom, rear, front, back, back, lateral, medial, inward, outward, lateral, left, right, proximal, distal) are not provided in this specification. They are not intended to be limiting, but are intended to facilitate the reader in describing at least one embodiment of the structure. Here, "proximal" is understood to mean toward the surgeon holding the handpiece 22, away from the surgical site where the wire 101 or drill bit can be applied. "Distal" is understood to mean away from the surgeon and toward the site where the wire 101 or drill bit is applied.

[0070] Figure 1 and Figure 2 An example chuck 20 is shown coupled to an example handpiece 22 , which together may comprise a wire driver. The chuck 20 includes a longitudinal axis 24 that coincides with the axis of rotation of certain portions of the chuck 20 and handpiece 22 .

[0071] The handpiece 22 may include a motor 26, a controller 28, a first actuator button 30, a second actuator button 32, and a power source 34, which are similar to commercially available handpieces (e.g., U drive). Power source 34 is schematically represented using example types of power sources including batteries and power cords. The identified power sources are not intended to be limiting. Examples of other additional alternative power sources include pneumatic power and hydraulic power.

[0072] exist Figures 3 to 6 The example chuck 20 best shown in FIG. 2 is oriented substantially along a longitudinal axis 24. The longitudinal axis 24 may also serve as an axis of rotation for the chuck 20. The chuck 20 includes a chuck housing 36 in which a rotatable part may be disposed. The housing 36 may be generally cylindrical and centered about the axis 24 and may define the axis 24.

[0073] The chuck 20 may also include an example clamping actuator (e.g., a clamping rod 38) that may be pivotally connected to the housing 36 via a pivot (i.e., a pin 40 that passes through a rod pivot hole 42 in the rod 38 and a rod mounting hole 44 in a mounting trunnion 46 of the housing 36). A screw 48 may be used to retain the pin 40 in the rod 38 and the trunnion 46. A gripping portion 50 may be separated from a yoke 52 of the rod 38 via the pivot hole 42.

[0074] The yoke 52 may be disposed substantially within the housing 36, passing through an opening 54 in the housing 36 aligned with the trunnion 46. The yoke 52 is slidably disposed in an actuator slot 56 of an actuator sleeve 58, thereby being connected to the actuator sleeve 58. The actuator sleeve 58 is slidably disposed within the housing 36 for movement along the axis 24. Engagement of the yoke 52 with the sleeve 58 causes the sleeve 58 to move axially along the axis 24 as the lever 38 pivots about the pin 40. A release spring 59 (e.g., a compression coil spring) may be disposed in the housing 36, between the housing and the sleeve 58, to bias the sleeve 58 to the release position, and with it, bias the lever 38 to the release position away from the grip handle 60 of the handpiece 22.

[0075] The clamping linkage between the lever 38 (more specifically, the grip portion 50) and the actuator sleeve 58 may include the yoke 52, the trunnion 46, and the actuator slot 56. An alternative arrangement may include an actuator in the form of an electric motor and a switch for the actuator in place of a lever, and a clamping linkage in the form of a gear transmission disposed between the electric motor and the actuator sleeve 58.

[0076] The drive shaft 62 is rotatably arranged in the housing 36 and on the longitudinal axis 24 to selectively rotate about it. The drive shaft 62 may include a jaw guide 64 to rotate therewith. The jaw guide 64 extends axially because it extends axially along the axis 24 and can define the axis 24 and can be at the distal end of the drive shaft 62. The jaw guide 64 includes a plurality of jaw channels 65, three being an example number, in which the jaws 66 are slidably arranged. The channels 65 are evenly distributed circumferentially around the axis 24, for example, in the case where there are three channels 65, the channels are separated by 120°. The drive shaft 62 may include an engagement end 68 for coupling with a rotating drive element (not shown) driven by the motor 26 of the handpiece 22. A first locating bearing 67 (e.g., a roller bearing 67) may be placed between the drive shaft 62 and the housing 36 to facilitate rotation therebetween. For the purpose of illustrating the space that may be occupied by the bearing 67, the bearing 67 is schematically illustrated as a torus having a solid cross-section. However, the bearing 67 may include rollers (e.g., ball rollers, cylindrical rollers, tapered rollers, needle rollers), an inner race, an outer race, and a roller cage. The bearing 67 may be an axial-radial load bearing, i.e., capable of bearing and accommodating thrust loads (i.e., axial loads) and radial loads.

[0077] The first locating bearing 67 can be mounted on a bearing support sleeve 69 fixed to the shaft 62. The bearing support sleeve 69 can have a first thread 71 on the inner diameter that is threadedly engaged with the drive shaft 62, and the drive shaft 62 can have a second thread 73 on the outer diameter. The relative positioning of the sleeve 69 and the shaft 62 can be established by the engagement of the inner diameter first shoulder 75 in the sleeve 69 with the outer diameter second shoulder 77 of the drive shaft 62. The shoulders 75, 77 can be parallel and each can have an angle of 45°. When the sleeve 69 is installed, this arrangement can introduce a tensile load in the sleeve 69 device and a compressive load in the drive shaft 62 between the corresponding threads 71, 73 and shoulders 75, 77.

[0078] The distal end of the drive shaft 62 may have a nose cap 70 disposed thereon for rotation therewith. The nose cap 70 may help retain a leaf spring disposed between the nose cap 70 and the jaw guide 64. The nose cap 70 may be partially surrounded by a nose housing 72 that is fixed to the distal end of the drive shaft 62 by a threaded engagement between the nose housing 72 and the nose cap 70.

[0079] A leaf spring 74 may be used to help retain the jaws 66 in the jaw channel 65. The leaf spring 74 may include a number of spring fingers 76 equal to the number of jaws 66 to engage each jaw 66. The fingers 76 may each extend from a circular base 78.

[0080] The engagement sleeve 80 includes a head 82 having an inclined engagement surface 84 on the inner surface of the engagement sleeve 80. The inclined engagement surface 84 is at least partially positioned to be axially aligned with the claw 66 and located radially outside the claw 66, such as Figure 5B 2, at least partially surrounding the jaws 66 in the engaged position. The engagement surface 84 can be selectively engaged with the drive surface 90. The engagement sleeve 80 can include a tail 86 that extends axially away from the head 82 in the proximal direction and helps keep the head 82 centered on the axis 24. A second locating bearing 79 (e.g., a roller bearing 79) can be disposed between the engagement sleeve 80 and the housing 36. More specifically, an inner race (not shown) of the bearing 79 can engage with the head 82. An outer race (not shown) of the bearing 79 can engage with the nose housing 72, which is fixed to the housing 36 as described above. Rollers and roller retainers (not shown) can be arranged between the races of the bearing 79. The bearing 79 can be configured to accommodate substantially only radial loads.

[0081] The actuator sleeve 58 may be slidably disposed on the tail portion 86 to move axially therewith and allow relative rotation therebetween. The axial movement of the sleeve 58 in the proximal direction along the tail portion 86 may be limited by a first retaining ring 81 that may be removably disposed on the proximal end of the tail portion 86. The axial movement of the sleeve 58 in the distal direction along the tail portion 86 may be limited by the head 82 of the engagement sleeve 80. The actuator sleeve 58 may be located therein.

[0082] A first thrust bearing 83 and a second thrust bearing 85 (e.g., roller bearings 83, 85) may be disposed at opposite ends of the actuator sleeve 58 to reduce the frictional resistance against relative rotation of the engagement sleeve 80 relative to the actuator sleeve 58, particularly when the sleeve 58 is biased to an extreme proximal or distal position on the tail 86.

[0083] When the actuator sleeve 58 is arranged in a first axial direction (e.g., a distal direction), the actuator sleeve 58 can selectively axially engage with the head 82 of the engagement sleeve 80, such engagement including indirect engagement, such as may occur when the thrust plate 87 and the thrust bearing 83 are disposed between the actuator sleeve 58 and the head 82. Similarly, when the actuator sleeve 58 is arranged in a second direction (e.g., a proximal direction), the actuator sleeve 58 can selectively axially engage with the proximal end of the tail 86 indirectly through the retaining ring 81, such engagement including engagement such as may occur when the second thrust plate 91 and the thrust bearing 85 are disposed between the actuator sleeve 58 and the retaining ring 81.

[0084] A first thrust bearing 83, which may include a roller and a roller cage, may be disposed between the head 82 and the actuator sleeve 58. A first thrust plate 87 may be disposed between the thrust bearing 83 and the head 82. Each of the thrust plate 87 and the head 82 may define opposing bearing races. A plurality of shim washers 89 (collectively referred to as a shim stack) may be disposed between the first thrust plate 87 and the head 82. Another thrust plate, not shown, may be disposed between the head 82 and the bearing 83. Still alternatively, the bearing 87 may include opposing integral bearing races, thereby eliminating the need to form races in the head 82 or the thrust plate 87.

[0085] The second thrust bearing 85 may be disposed above the tail portion 86 between the actuator sleeve 58 and the first retaining ring 81. The tail portion 86 of the engagement sleeve 80 may carry a second thrust plate 91 between the second thrust bearing 85 and the first retaining ring 81. The second thrust plate 91 may be sized in diameter for axial engagement by the second thrust bearing 85 and retained by the ring 81. Alternative bearing structures as described for the first thrust bearing 87 may also be employed herein. A third thrust plate 97 may be disposed between the second thrust bearing 85 and the second thrust plate 91. A spring washer 99 may be disposed between the thrust plates 91, 97. The drive shaft 62 may have a proximal portion 122 terminating at a proximal end 124 of the drive shaft 62. An input shaft guide 126 may be slidably disposed on the proximal portion 122. The input shaft guide 126 and the proximal portion 122 may include complementary features, wherein the cross-sectional profile of the axial passage through the guide 126 is complementary to the cross-sectional profile of the proximal portion 122. Such a profile may include features that allow the guide to translate axially along the proximal portion 122 while resisting relative rotation between the input shaft guide 126 and the drive shaft 62, and may be a substantially constant axially extending non-circular section, such as opposing flat surfaces, splines, and similar configurations. A second retaining ring 128 (e.g., a snap ring 128) may be disposed in a circumferential groove in the proximal portion 122, proximate the proximal end 124. A drive spring 130 (e.g., a compression coil spring 130) may be disposed on the proximal portion 122, between the bearing support sleeve 69 and the input shaft guide 126. The drive spring 130 may engage each of the bearing support sleeve 69 and the input shaft guide 126, thereby pressing the input shaft guide 126 against the second retaining ring 128. The input shaft guide 126 may be used to driveably connect the drive shaft 62 to an input shaft (not shown) of the handpiece 22. The input shaft may be disposed between the motor 26 and the drive shaft 62 and drivingly connects the motor 26 and the drive shaft 62 when the chuck 20 is mounted to the handpiece 22 .

[0086] The jaws 66 each have a gripping surface 88 facing the axis 24 and a drive surface 90 substantially opposite the gripping surface 88. The jaws 66 also have a protrusion 92 on a first lateral side 94 and a cavity 96 on a second lateral side 98. The jaws may have a spring groove 95 intersecting the drive surface for receiving one of the fingers 76 of the leaf spring 74.

[0087] The lateral sides 94, 98 of the jaws 66 may be separated by an angle α that is substantially equal to 360° divided by the number of jaws. In the present example, where there are three jaws 66, the angle α may be substantially equal to 120°. The angle α of a chuck having a greater number of jaws will have a proportionally lower value. The facing lateral sides 94, 98 of adjacent jaws 66 may be substantially parallel to each other, i.e., at a 0° angle to each other. The shaft 101 disposed between the facing lateral sides 94, 98 may be sandwiched between two adjacent jaws 66. However, as Figure 8C and Fig.8D As shown in , the protrusion 92 provides an angle β between the facing surface 100 and the facing lateral side 98 of the protrusion 92, which is related to the angle β between the facing sides 94, 98. An increase in the angle β may cause a shaft 101 (e.g., a wire, a pin, a tool bit) disposed between the surface 100 and the lateral side 98 to be pushed toward the axis 24 without being squeezed as the surface 100 and the lateral side 98 move closer together.

[0088] Figure 8C and Fig.8D The example of FIG. 1 shows an angle β that increases from 0° (without the protrusion 92) to 30° (with the protrusion 92 introduced). The protrusion 92 of each jaw 66 is at least partially arranged in the cavity 96 of the adjacent jaw 66 in at least one position of the chuck 20, which is Figure 8C 6, so that the jaws 66 are staggered. The protrusion 92 of each jaw 66 can be substantially complementary to the cavity 96 in the adjacent jaw 66.

[0089] The inclined engagement surface 84 of the engagement sleeve 80 is substantially centered on the axis 24 and substantially parallel to the drive surface 90. The engagement surface 84 may include a plurality of circumferentially distributed engagement segments. The displacement of the jaw 66 relative to the inclined engagement surface 84 in the clamping direction causes the clamping surface 88 to be displaced toward the axis 24. The clamping direction of the surface 84 and the jaw 66 is consistent with the movement of the engagement surface 84 toward the jaw 66, for example, in the clamping condition, so that the sleeve 80 is relative to the housing 36 along the Figures 5A-5C The jaw guide 64 is moved in a leftward direction in the embodiment of the present invention, wherein the jaw guide 64 remains laterally fixed relative to the housing 36.

[0090] The jaws 66 and the protrusions 92 may each have an inclined distal entry surface 102 and 104, respectively, to receive the shaft 101 from the distal end of the chuck 20 and the handpiece 22. The inclined distal surfaces 102, 104 may taper in the proximal direction toward the axis 24 in the installed condition. Such inclined distal surfaces 102, 104 may help guide the end of the shaft 101 that engages the inclined surfaces 102, 104 to slide further axially and radially along the surfaces 102, 104 into the receiving hole 106 between the jaws 66. As the jaws 66 move together, the shaft 101 is moved into the clamped position within the hole 106 between the clamping surfaces 88 of the jaws 66. The jaws 66 are capable of receiving a small diameter shaft 101', i.e., a shaft 101 having a diameter at the small diameter end of the clamping range of the chuck 20, when the protrusions 92 are at least partially disposed in the cavities 96 in the adjacent jaws 66.

[0091] The jaws 66 and the protrusions 92 may also each have inclined proximal entry surfaces 108 and 110, respectively, to receive the shaft 101 from the proximal ends of the chuck 20 and the handpiece 22. The inclined proximal surfaces 108, 110 may taper in the distal direction toward the axis 24 in the installed condition. Such inclined proximal surfaces 108, 110 may help guide the end of the shaft 101 that engages the inclined surfaces 108, 110 to slide further axially and radially along the surfaces 108, 110 into the receiving hole 106 between the jaws 66. As the jaws 66 move together, the shaft 101 is moved into the clamped position within the hole 106 between the clamping surfaces 88 of the jaws 66.

[0092] The jaws 66 may also include a flange portion 112 opposite the gripping surface 88, which may partially incorporate the drive surface 90. The flange portion 112 of each jaw 66 may extend laterally beyond side walls 114 of the jaws 66, which are slidably disposed within the walls of the channel 65. The engagement of the underside of the flange portion 112 with the jaw guide 64 may prevent the jaws 66 from overtraveling within the channel 65 and may prevent the gripping surface 88 from moving beyond the axis 24.

[0093] The jaws 66 may have alternative configurations of the protrusions 92 and cavities 96. Fig.9A -C and Fig. 10A-D shows an alternative example configuration of the jaw 66'. The protrusion 92' may extend from the first lateral side 94' beyond the clamping surface 88 at the outer side edge to define a facing surface 100'. The angle β' between the facing surface 100' and the second lateral side 98' may be 60°. The protrusion 92' may be at least partially received by the complementary cavity 96'. The jaw 66' and the protrusion 92' may each have an inclined distal entry surface 102' and 104', respectively. The jaw 66' and the protrusion 92' may also each have an inclined proximal entry surface 108' and 110', respectively. The jaw 66' may jointly define a receiving hole 106'.

[0094] Fig.11A -C and Fig. 12A -Another alternative construction of the claw 66" shown in -D may have a first protrusion 92" and a first cavity 96" on the first lateral side 94" and a second protrusion 92"' and a second cavity 96"' on the second lateral side 98". The angle β" between the facing surfaces 100", 100"' may be 120°. The claw 66" and the protrusion 92" may each have an inclined distal entry surface 102" and 104". The protrusion 92"' may have an inclined distal entry surface 104"'. The claw 66" and the protrusion 92" may each also have an inclined proximal entry surface 108" and 110". The protrusion 92"' may have an inclined proximal entry surface 110"'. The claw 66" may jointly define a receiving hole 106".

[0095] The chuck 20 may be used as follows. The chuck 20 may be mounted on the handpiece 22 in a known manner, thereby drivingly connecting the drive shaft 62 to the motor 26. Figure 5A The chuck 20 is shown in the disengaged (ie, released) position. Figure 5B The chuck 20 is shown in an engaged or clamped condition, receiving a small diameter shaft 101'. Figure 5C The chuck 20 shown in FIG. 1 is also in an engaged or clamped condition, receiving a large diameter shaft 101″, i.e., a shaft 101 having a diameter at the large diameter end of the clamping range of the chuck 20. For example, the clamping range might be 0.5 mm to 3.5 mm, resulting in a maximum to minimum ratio of 7:1. An alternative example range of 0.5 mm to 2.0 mm would result in a 4:1 ratio. Figure 5B The axis 101' and Figure 5C The clamping of the shaft 101″ in the grip portion 50 is responsive to the application of the force F on the grip portion 50, thereby biasing the grip portion 50 toward the grip handle 60 to move the grip portion 50 toward the grip handle 60.

[0096] By passing the shafts 101, 101', 101" through Figure 2The rear access hole 116 shown in FIG. 1 is located in the rear portion 118 of the housing 36 and the Figure 1 The shaft 101, 101', 101" can be inserted into the chuck 20 through one of the front access holes 120 shown in the figure that passes through the nose mask 70. If passing through the front access hole 120, the shaft 101 can engage the distal access surface 102, 102', 102" of one of the jaws 66, 66', 66" or the distal access surface 104, 104', 104", 104"' of one of the protrusions 92. If passing through the rear access hole 116, the shaft 101 can engage the proximal access surface 108 of one of the jaws 66, 66', 66" or the proximal access surface 110, 110', 110", 110'" of one of the protrusions. To accommodate entry of the shaft 101, 101', 101" from the rear, the drive shaft 62 may include a drive shaft passage 121 therethrough, which is coaxial with the axis 24. The diameter of the passage 121 may serve as a limit to the maximum allowable diameter of the shaft 101, 101', 101" that can be received by the chuck 20.

[0097] One end of the shaft 101, 101', 101" is guided toward the axis 24 by entry surfaces 102, 102', 102" and 104, 104', 104", 104"' located on the distal end or entry surfaces 108 and 110, 110', 110", 110"' located on the proximal end. The rod 38 can be grasped on its grip portion 50 by the operator's (i.e., surgeon's) fingers, and the rod 38 is squeezed toward the grip handle 60. The rod 38 pivots about the pivot 40. The yoke 52 is inclined in the distal direction, and the actuator sleeve 58 is also displaced in the distal direction by the engagement of the yoke 52 with the actuator sleeve 58 at the groove 56. The second locating bearing 79 can be axially constrained on the distal side. An annular reaction plate 132 can be arranged on the proximal side of the second locating bearing 79 to be engaged by the release spring 59. The release spring 59 can be compressed between the first thrust plate and the reaction plate 132. The release spring 59 resists displacement of the sleeve 58 in the distal direction. The actuator sleeve 58 is also axially engaged with the head 82 of the engagement sleeve 80 via the first thrust bearing 83, the thrust plate 87 and the spacer washer 89, i.e., axially connected. The rod 38 can therefore be connected to the engagement sleeve 80. Squeezing the rod 38 can cause the inclined engagement surface 84 of the engagement sleeve 80 to engage the drive surface 90 of the claw 66 and displace the claws 66, 66', 66" and the clamping surface 88 toward the axis 24.

[0098] By describing the displacement of the jaws 66, 66', 66" in more detail, the axial displacement of the sleeve 58 in the distal direction produces an axial displacement of the head 82 and the entire engagement sleeve 80 and the first thrust bearing 83 in the distal direction. The distal axial displacement of the head 82 along the axis 24 causes the inclined surface 84 of the engagement sleeve 80 to act on the drive surface 90 of the jaws 66, 66', 66". In response to the force of the head 82 abutting against the jaws 66, 66', 66", the jaws 66, 66', 66" are restricted to radial movement, i.e., movement toward and away from the axis 24, by the jaw channels 65. Therefore, axial movement of the sleeve 80 results in sliding of the inclined surface 84 on the drive surface 90 and radial displacement of the jaws 66, 66', 66" toward the axis 24, such displacement being limited by the engagement of the clamping surface 88 on the shaft 101, 101', 101". As the clamping surfaces 88 move closer together, facing surfaces 100 , 100 ′, 100 ″, 100 ′″ of the lateral sides 98 , 98 ′, 98 ″ and / or the protrusions 92 , 92 ′, 92 ″, 92 ′″ of the jaws 66 drive the shaft 101 toward the axis 24 .

[0099] Jaws having complementary protrusions and cavities may be incorporated into any other style of chuck employing jaws. Patent publication PCT / US2017 / 062754 shows an alternative construction of a chuck for a wire drive which may have a rod connected to a jaw guide adapted for axial movement, not shown here. The jaw guide and the jaws disposed therein may be axially displaced by squeezing the rod. Axial displacement of the jaw guide may press the driving surface of the jaw against the inclined engagement surface of the engagement sleeve, thereby displacing the clamping surface of the jaw toward the axis. In FIGS. 13 to 14, the jaws may be provided with a plurality of guides which are adapted to move the jaws in a axial direction. Fig.19C Other example alternative configurations are shown in .

[0100] Fig.13A , Fig. 13B and Fig. 13C Shown for use with Fig.14 and Fig.15 The example staggered jaws 266 used with the example keyless chuck 220 shown in FIG. Keyless chucks are commercially available, wherein the example chucks are available as The example keyless chuck 220 clamps the shaft 301 disposed on the longitudinal axis 224 without the use of a rod such as the rod 38 of the chuck 20. Instead, clamping can be achieved by having one person hold the sleeve 280 while using a handpiece such as the handpiece 22 to rotate the drive shaft 262 in the tightening direction while the external engagement sleeve 280 is stalled. Clamping can also be achieved by manually holding the sleeve 280 and the collar 258 and rotating the collar 258 and the sleeve 280 relative to each other in the tightening direction.

[0101] The axially extending jaw guide 264, which defines an axis 224 also serving as an axis of rotation and is centered on the axis 224, slidably holds the jaw 266 in a jaw channel 265 formed therein. The jaw 266 has a clamping surface 288 facing the axis 224 and a drive surface 290 substantially opposite the clamping surface 288. The jaws 266 each have a protrusion 292 on a first lateral side 294 and a cavity 296 on a second lateral side 298. As shown for the jaws 66, 66' and 66", when the jaws 266 are sufficiently close to the axis 224 in the radial direction, the adjacent jaws 266 have the protrusion 292 of one jaw 266 disposed in the cavity 296 of the other jaw 266.

[0102] As with the jaws 66 and protrusions 92, the jaws 266 and protrusions 292 can each have inclined distal access surfaces 302 and 304, respectively, to facilitate receiving the shaft 301 from the distal end of the handpiece 22 and chuck 20. Similarly, the jaws 266 and protrusions 292 can each have inclined proximal access surfaces 308 and 310, respectively, to receive the shaft 301 from the proximal end of the chuck 220 and handpiece 22.

[0103] Such inclined distal surfaces 302, 304 can help guide the end of the shaft 301 that engages the inclined surfaces 302, 304 to slide further axially and radially along the surfaces 302, 304 into the receiving hole 306 between the jaws 266. The hole 306 can be at least partially defined by the facing surface 300 of the protrusion 292 and the second lateral side 298 of the jaws 266. As the jaws 266 move together, the shaft 301 is moved into the hole 306 between the clamping surfaces 288 of the jaws 266 to a clamped position.

[0104] To accommodate entry of the shaft 301, the jaw driver 274 may include a driver passage 321 therethrough, which is coaxial with the axis 224. The diameter of the passage 321 may serve as a limit to the maximum allowable diameter of the shaft 301 that may be received by the chuck 220.

[0105] The jaws 266 may also include a flange portion 312 opposite the gripping surface 288, which may partially engage the drive surface 290. The flange portion 312 of each jaw 266 may extend laterally beyond the sidewalls 314 of the jaws 266, which are slidably disposed within the walls of the channel 265. The engagement of the underside of the flange portion 312 with the jaw guide 264 may prevent the jaws 266 from overtraveling within the channel 265 and may prevent the gripping surface 288 from moving beyond the axis 224.

[0106] The engagement sleeve 280 includes an inclined engagement surface 284 thereon (ie, therein). The inclined engagement surface 284 is at least partially arranged radially outward of the claw 266, thereby at least partially surrounding the claw 266 in the engaged position, such as Fig.15 The engagement surface 284 is substantially centered about the axis 224 and is substantially parallel to the drive surface 290. The axially extending jaw guide 264 may be substantially fixed relative to the engagement sleeve 280. The engagement sleeve 280 may be fixedly coupled to the supplemental sleeve 297.

[0107] The drive shaft 262 may be fixed to the drive sleeve 270 so as to rotate integrally therewith about the axis 224. The drive sleeve 270 may be threadedly engaged with the shank 272 of the jaw driver 274. The jaw driver 274 includes an axially displaceable actuation head 375, which is rotatably fixed to but slidably disposed in the jaw guide 264. This relationship may be achieved by providing a plurality of circumferentially distributed finger grooves 278 in the jaw guide 264 and providing the same number of axially extending engagement fingers 282 on the head 276. The finger grooves 278 may be aligned with and connected to the jaw channel 265 and lead to the jaw channel 265. A plurality of distal abutment surfaces 286 (the number of which is equal to the number of jaws 266) may be arranged on the head 276, circumferentially interposed between the fingers 282. Abutment surface 286 may engage a proximal abutment surface 295 of jaw 266 at a proximal end of jaw 266 .

[0108] The inward radial movement of the head 276 is caused by the head 276 resisting the axial displacement of the claw 266. More specifically, as the drive shaft 262 rotates relative to the engagement sleeve 280 in the first direction, the drive sleeve 270 rotates relative to the claw driver 274. The threaded engagement between the claw driver 274 and the drive sleeve 270 causes relative axial displacement between the driver 274 and the sleeve 270 in the engagement direction. The distal abutment surface 286 of the claw driver 274 axially engages and pushes against the proximal abutment surface 295 of the claw 266, thereby forcing the drive surface 290 of the claw 266 to rest on the inclined surface 284 of the engagement sleeve 280 and causing the claw 266 to be axially displaced relative to and resisting the engagement sleeve 280 in the engagement direction. As the drive surface 290 slides over the inclined surface 284 , movement of the jaws 266 along the axis 224 pushes the clamping surface 288 of the jaws 266 against the shaft 301 to clamp the shaft 301 .

[0109] Jacobs keyed chuck 420 may also incorporate complementary protrusions and cavities in jaws 466. Jacobs keyed chucks are commercially available, with example chucks being Purchased as part of a System 8 power tool set. Figure 16-19C The example Jacobs keyed chuck 420 shown in FIG. 4 has three substantially cylindrical jaws 466 slidably disposed in holes (i.e., channels 465) in an axially extending and substantially cylindrical jaw guide 464. The channel 465 may be at an angle γ with a longitudinal axis 424 that may be defined by the jaw guide 464. The longitudinal axis 424 may also serve as an axis of rotation. The drive sleeve 470 drives the three jaws 466 axially distally relative to rotation of the jaw guide 464 about the axis 424 in a first relative rotational direction, and simultaneously drives the three jaws 466 radially inward toward the axis 424 due to the angle γ to engage and clamp the shaft 501 through the clamping surfaces 488 of the jaws 466. Relative rotation between the sleeve 470 and the jaw guide 464 in a second rotational direction opposite to the first rotational direction drives the jaws 466 axially inward toward the handpiece 22 and radially away from the axis 424 and the axis 501. A chuck key, not shown, may be used to rotate the sleeve 470 relative to the jaw guide 464 .

[0110] The clamping surface 488 of each jaw 466 faces the axis 424. The drive surface 490 is positioned on the jaw 466 at the distal end of the jaw 466 in a manner substantially opposite to the clamping surface 488. Fig.18A and Fig.18B The jaw 466 shown in the figure can have a first protrusion 492 and a first cavity 496 on a first lateral side 494, and can have a second protrusion 492' and a second cavity 496' on a second lateral side 498. As shown for the jaw 66", adjacent jaws 466 can have the protrusion 492, 492' of one jaw 466 disposed in the cavity 496', 496 of the other jaw 466 when the jaw 466 is radially close enough to the axis 424. The jaw 466 and the protrusion 492, 492' each have an inclined distal entry surface 502, 504 and 504', respectively, to facilitate receiving the shaft 501 from the distal end of the handpiece 22 and the chuck 420.

[0111] Such inclined distal surfaces 502, 504, 504' can help guide the end of the shaft 501 that engages the inclined surfaces 502, 504, 504' to slide further axially and radially along the surfaces 502, 504, 504' into the receiving hole 506 between the jaws 466. The hole 506 can be at least partially defined by the facing surfaces 500, 500' of the protrusions 492, 492' and the clamping surface 488. As the jaws 466 move together, the shaft 501 is moved into the clamped position within the hole 506 between the clamping surfaces 488 of the jaws 466 by the facing surfaces 500, 500'.

[0112] To accommodate proximal entry of shaft 501 into jaw guide 464 beyond jaws 466, jaw guide 464 may include a guide channel 521 therethrough that is coaxial with axis 424. The diameter of channel 521 may serve as a limit to the maximum allowable diameter of shaft 501 that may be received by chuck 420.

[0113] The jaw guide 464 includes an example inclined engagement surface 484 that is co-disposed in the channel 465 relative to the axis 424. The inclined engagement surface 484 is at least partially disposed radially outward of its associated jaw 466, thereby at least partially surrounding the jaw 466 in the engaged position, as shown in FIG. Fig.17 The inclined engagement surface 484 is substantially centered about the axis 424 and is substantially parallel to the drive surface 490 of the associated pawl 466 .

[0114] The jaw guide 464 may include an axially extending drive shaft 462 to rotate integrally therewith about the axis 424. The drive shaft 462 may be selectively engaged with the handpiece 22. The drive sleeve 470 may drive the jaws 466, i.e., axially displace the jaws 466, through a threaded connection between the drive sleeve 470 and the jaws 466. By providing an internal (i.e., female) thread 474 in the drive sleeve 470, an outwardly facing threaded surface 472 of each jaw 466 located on the side opposite to the axis 424 and at the proximal end of the jaw 466 may be engaged. The sleeve 470 may include a split nut 476 that is provided on the jaws and pressed into the sleeve 470. The sleeve 470 has a circle of chuck sleeve teeth 486 distributed on the distal end of the sleeve 470 and centered about the axis 424 and a plurality (e.g., three) of pin holes 478 located in the jaw guide 464 at a location distally beyond the sleeve 470. A chuck key (not shown) may include a pin surrounded by the chuck key teeth.

[0115] As with chucks 20 and 220, when the shaft 501 is clamped, the inward radial movement of the jaws 466 of the chuck 420 is caused by the relative axial displacement of the chuck 466 relative to the inclined surface 484 engaged by the drive surface 490 of the chuck 466. This relative axial displacement can be provided by using a chuck key. The chuck key engages with the chuck when the pin of the key is placed in one of the pin holes 478 and the teeth of the key engage with the chuck sleeve teeth 486. Once engaged, the key is rotated in the tightening direction, thereby rotating the sleeve 470 relative to the jaw guide 464 in the first (i.e., tightening) direction. The rotation of the sleeve 470 relative to the jaw guide 464 can also be manually achieved by rotating the jaw guide 464 using the handpiece 22 while engaging the sleeve with fingers. The rotation of the collar 258 can cause the drive shaft 262 to rotate therewith. This manual clamping can be performed by using a key to screw the jaw 466 against the shaft 501. As the sleeve 470 and the nut 476 rotate relative to the jaw guide 464 in a first direction, the jaw 466 is driven axially distally by the action of the nut 474 on the threaded surface 472 of the jaw 466. The threaded engagement between the jaw 466 and the drive sleeve 470 causes relative axial displacement between the guide 464 and the sleeve 470. The driving surface 490 of the jaw 466 acting on the inclined surface 484 of the jaw guide 464 causes the clamping surface 488 of the jaw to move radially inward. With the driving surface 490 sliding on the inclined surface 484, the movement of the jaw 466 along the axis 424 pushes the clamping surface 488 of the jaw 466 against the shaft 501 to clamp the shaft 501. Rotation of the key in the opposite direction releases the shaft 501. Fig.19B The jaws 466 are shown clamped against the small diameter shaft 501 '. Fig.19C The jaws 466 are shown gripping the large diameter shaft 501".

[0116] Jaw chucks having staggered jaws have been disclosed.

[0117] In the accompanying drawings, the same reference numerals represent the same elements. In addition, some or all of these elements can be changed. Regarding the media, processes, systems, methods, inspirations, etc. described herein, it should be understood that, although the steps of such processes, etc. have occurred according to a certain orderly sequence, such processes can be practiced using the steps performed in a sequence different from the sequence described herein. It should also be understood that some steps can be performed simultaneously, other steps can be added, or some steps described herein can be omitted. In other words, the description of the process herein is provided for the purpose of illustrating certain embodiments, and should never be interpreted as limiting the claims.

[0118] Therefore, it will be understood that the above description is intended to be illustrative rather than restrictive. After reading the above description, many embodiments and applications other than the examples provided will be apparent. The scope should not be determined with reference to the above description, but should be determined with reference to the full scope of the attached claims and the equivalents of the claims. It is expected and intended that future developments will occur in the technology discussed herein, and the disclosed systems and methods will be incorporated into such future embodiments. In a word, it should be understood that the present application is capable of modification and variation.

[0119] As used herein, the adverb “substantially” means that the shape, structure, size, quantity, time, etc. may be different from the precisely described geometry, distance, size, quantity, time, etc. due to materials, machining, manufacturing, data transmission, computing speed, etc.

[0120] Unless expressly indicated to the contrary herein, all terms used in the claims are intended to be given their ordinary meanings as understood by those skilled in the art to which the technology described herein belongs. In particular, the use of singular articles such as "a", "an", "the", "said", etc. should be understood to recite one or more of the elements described, unless an express limitation to the contrary is given in the claims.

[0121] The abstract is provided to allow the reader to quickly ascertain the nature of the technical disclosure. This document is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing detailed description, it can be seen that the various features are grouped in the various embodiments for the purpose of simplifying the disclosure. The method of the present disclosure should not be interpreted as reflecting an intention that the claimed embodiments require more features than those expressly recited in each claim. On the contrary, as reflected in the appended claims, the inventive subject matter lies in less than all the features of a single disclosed embodiment. Therefore, the following claims are hereby incorporated into the detailed description, wherein each claim independently serves as a separately claimed subject matter.

Claims

1. A chuck for clamping a shaft, comprising: an axially extending jaw guide defining a longitudinal axis and including a first plurality of jaw channels distributed circumferentially about the axis; a plurality of staggered jaws, said jaws being slidably disposed in said jaw channel, and each jaw having a gripping surface facing said axis and a drive surface substantially opposite said gripping surface, and having a protrusion on a first lateral side and a cavity on a second lateral side, wherein said protrusion of each jaw is at least partially disposed in said cavity of an adjacent jaw; and an inclined engagement surface located on an inner surface of the jaw guide and one of the engagement sleeve, the engagement surface being substantially centered on the axis and substantially parallel to the drive surface, wherein displacement of the jaw relative to the engagement surface in a clamping direction is radial movement of the clamping surface toward and away from the axis.

2. The chuck according to claim 1, wherein: The jaws define a receiving aperture adapted to receive and clamp a shaft ranging from a first diameter to a second, larger diameter, and the projections are disposed within the cavity when the jaws are positioned to clamp a shaft having the first diameter.

3. The chuck according to claim 1, wherein: The jaw channels and jaws are evenly distributed about the axis, and the protrusion of each jaw is substantially complementary to the cavity in the adjacent jaw.

4. The chuck according to claim 1, wherein: The claw has each of the protrusions and cavities on each of the first lateral side and the second lateral side, and the protrusion of the first lateral side of each claw is at least partially arranged in the cavity of the second lateral side of the adjacent claw, and the protrusion of the second lateral side of each claw is at least partially arranged in the cavity of the first lateral side of the adjacent claw.

5. The chuck according to claim 1, wherein: The claw and the protrusion each have an inclined distal surface.

6. The chuck according to claim 1, wherein: The detent and the projection each have an inclined proximal surface.

7. The chuck according to claim 1, wherein: The jaws and the projections each have an inclined distal surface and have an inclined proximal surface.

8. The chuck according to claim 1, wherein: The protrusion extends into a gap between facing lateral sides of adjacent jaws proximate the clamping surface.

9. The chuck according to claim 1, wherein: The protrusion extends beyond the clamping surface toward the axis.

10. The chuck according to claim 1, wherein: The ratio of the largest shaft to the smallest shaft that can be accommodated by the chuck without squeezing is at least 4:

1.

11. The chuck according to claim 1, wherein: The chuck also includes: a generally cylindrical housing in which the jaw guide, the jaw, and the engagement sleeve are rotatably arranged; and A clamping lever is pivotally mounted to the housing and connected to one of the jaw guide and the engagement sleeve for axial displacement thereof.

12. The chuck according to claim 1, wherein: The inclined engagement surface is located on the engagement sleeve, and the jaw guide is basically fixed relative to the engagement sleeve, and the chuck also includes an axially displaceable actuator head axially engaged with the jaw, and further, the axial displacement of the actuator head in the engagement direction pushes the drive surface of the jaw against the inclined engagement surface and causes the jaw to axially displace relative to the engagement sleeve.

13. The chuck according to claim 1, wherein: The inclined engagement surface is located on the jaw guide, and the jaw has a threaded surface disposed thereon that threadably engages a thread disposed on a drive sleeve.

14. A chuck for a wire drive, wherein: The chuck comprises: an axially extending jaw guide defining a longitudinal axis and including a first plurality of jaw channels distributed circumferentially about the axis; a plurality of staggered jaws, said jaws being slidably disposed in said jaw channel, and each jaw having a gripping surface facing said axis and a drive surface substantially opposite said gripping surface, and having a protrusion on a first lateral side and a cavity on a second lateral side, wherein said protrusion of each jaw is at least partially disposed in said cavity of an adjacent jaw; and An engagement sleeve having an inclined engagement surface on its inner surface, the engagement surface being substantially centered on the axis and substantially parallel to the drive surface, wherein displacement of the jaw guide relative to the engagement sleeve in the clamping direction is radial movement of the clamping surface toward and away from the axis.

15. The chuck according to claim 14, wherein: The chuck also includes: a generally cylindrical housing in which the jaw guide, the jaw, and the engagement sleeve are rotatably arranged; and A clamping lever is pivotally mounted to the housing and connected to one of the jaw guide and the engagement sleeve for axial displacement thereof.

16. The chuck of claim 14, wherein: The jaws define a receiving aperture adapted to receive and clamp a shaft ranging from a first diameter to a second, larger diameter, and the projections are disposed within the cavity when the jaws are positioned to clamp a shaft having the first diameter.

17. The chuck of claim 14, wherein: The jaw channels and jaws are evenly distributed about the axis, and the protrusion of each jaw is substantially complementary to the cavity in the adjacent jaw.

18. The chuck of claim 14, wherein: The claw has each of the protrusions and cavities on each of the first lateral side and the second lateral side, and the protrusion of the first lateral side of each claw is at least partially arranged in the cavity of the second lateral side of the adjacent claw, and the protrusion of the second lateral side of each claw is at least partially arranged in the cavity of the first lateral side of the adjacent claw.

19. The chuck of claim 14, wherein: The claw and the protrusion each have an inclined distal surface.

20. The chuck of claim 14, wherein: The detent and the projection each have an inclined proximal surface.

21. The chuck of claim 14, wherein: The jaws and the projections each have an inclined distal surface and have an inclined proximal surface.

22. The chuck of claim 14, wherein: The projection extends across a gap between facing lateral sides of adjacent jaws proximate the clamping surface.

23. The chuck of claim 14, wherein: The protrusion extends beyond the clamping surface toward the axis.

24. The chuck of claim 14, wherein: The ratio of the largest shaft to the smallest shaft that can be accommodated by the chuck without squeezing is at least 4:

1.

25. The chuck of claim 14, wherein: The jaw guide is at the distal end of the drive shaft.

26. The chuck of claim 14, wherein: The chuck also includes: a generally cylindrical housing defining a longitudinal axis; an axially extending drive shaft rotatably disposed within the housing on the longitudinal axis for selective rotation about the longitudinal axis and including the jaw guide at a distal end of the drive shaft; wherein the engagement sleeve is rotatably arranged within the housing on the longitudinal axis to selectively rotate about the longitudinal axis, and the engagement surface is at least partially arranged to be axially aligned with the drive surface and arranged radially outward of the drive surface and selectively engage with the drive surface; an actuator sleeve slidably and non-rotatably disposed proximate the engagement surface on the longitudinal axis and selectively axially engaged with the engagement sleeve in each of a first axial direction and a second axial direction; a first locating bearing, the first locating bearing being an axially-radially loaded bearing, the bearing being arranged between the drive shaft and the housing on the proximal side of the actuator sleeve; a second locating bearing, the second locating bearing being a substantially radially only load bearing arranged between the engagement sleeve and the housing distally of the actuator sleeve; and A clamping actuator is connected to the actuator sleeve by a clamping linkage to axially displace the engagement sleeve, wherein displacement of the engagement sleeve relative to the jaw guide in a clamping direction displaces the clamping surface toward the axis.

27. The chuck of claim 26, wherein: The chuck also includes a bearing support sleeve disposed on and fixed to the drive shaft, and the inner race of the first locating bearing is fixed to the drive shaft.

28. The chuck of claim 27, wherein: The bearing support sleeve includes threads on its inner diameter and a first shoulder on the inner diameter at a proximal end of the threads, and the drive shaft includes threads on a tail portion of the drive shaft and a second shoulder on an outer diameter of the drive shaft at a proximal end of the threads, and the threads of the bearing support sleeve are threadably engaged with the threads of the tail portion, and the corresponding shoulders are engaged with each other.

29. The chuck of claim 26, wherein: The clamp actuator comprises a clamp rod pivotally mounted to the housing, and the clamp linkage comprises a yoke portion of the clamp rod engaging the actuator sleeve, displacement of the engaging sleeve in a clamping direction relative to the jaw guide displacing the clamping surface toward the axis.

30. The chuck of claim 26, wherein: The chuck also includes a first thrust bearing disposed between a distal end of the actuator sleeve and the engagement sleeve and a second thrust bearing disposed between a proximal end of the actuator sleeve and the engagement sleeve.

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