Chuck

Abstract

This invention provides a chuck that can improve work efficiency when processing irregularly shaped workpieces. [Solution] The chuck 1 comprises a chuck body 131, three sliding bodies 132 disposed on the chuck body 131 so as to be slidable along three virtual axes J21, J22, and J23, and three arms 134 arranged to surround the central axis J1 of the chuck body 131, each having a gripping portion 1341 and a pivoted portion 1342 pivotally supported by the sliding body 132. The tip of the gripping portion 1341 of each of the three arms 134 is positioned to face the central axis J1 side of the gripping portion 1341 of the adjacent arm 134, and the central axis J1 side of the adjacent sliding body 132 that pivots each arm 134 is positioned so as to be able to abut against the side opposite to the central axis J1 side of the gripping portion 1341.

Description

Technical Field

[0004] , , , ,

[0005] , , ,

[0001] The present invention relates to a chuck.

Background Art

[0002] An NC machining apparatus for bone members provided with a bone member support portion for supporting a bone member has been proposed (see, for example, Patent Document 1). In the surgery using this NC machining apparatus for bone members, for example, shape machining is performed on the collected bone collected from the patient himself / herself during the surgery using this NC machining apparatus for bone machining, and transplantation is performed to the site that requires treatment. Here, since the collection of bone is performed manually, the shape of the collected bone is not stable.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in the NC machining apparatus for bone members as described in Patent Document 1, a scroll chuck is often adopted. However, many scroll chucks assume that the workpiece is cylindrical, and due to the state of bone collection, the skeletal shape of the patient, etc., the cross-sectional shape of the collected bone is irregular. Therefore, in the case of a scroll chuck, it may not be possible to firmly grip the bone in the collected state. Also, in this case, it becomes necessary for the staff at the medical site to process the bone collected using a cutting tool such as a file into a shape that can be firmly gripped by the scroll chuck, and there is also a risk that the work efficiency at the medical site will decrease.

[0005] The present invention has been made in view of the above circumstances, and an object thereof is to provide a chuck capable of improving the work efficiency when machining a workpiece having an irregular shape. [Means for solving the problem]

[0006] To achieve the above objective, the chuck according to the present invention is The zipper body and Multiple sliding bodies are disposed on the chuck body so as to be slidable along multiple virtual axes that extend radially from the central axis of the chuck body, passing through the workpiece holding position where the workpiece to be held is positioned, in a direction perpendicular to the central axis, The chuck body comprises a plurality of arms, each having a gripping portion that is arranged to surround the central axis and curved such that the side facing the central axis is recessed, and a pivoted portion that is continuous with the base end of the gripping portion and pivotally supported on each of the plurality of sliding bodies so as to be rotatable, Each of the multiple arms is arranged such that the tip of the gripping portion faces the central axis side of the gripping portion of another adjacent arm in one circumferential direction around the central axis, and the central axis side of the sliding body that pivots each of them and the other adjacent sliding body in the circumferential direction can contact the side opposite to the central axis side of the gripping portion. [Effects of the Invention]

[0007] According to the present invention, each of the multiple arms is arranged to surround the central axis of the chuck body and has a gripping portion that is curved so as to be recessed on the side facing the central axis, and a pivoted portion that is continuous with the base end of the gripping portion and pivotally supported by each of the multiple sliding bodies. The tip of the gripping portion of each of the multiple arms is positioned to face the central axis side of the gripping portion of the adjacent arm in the circumferential direction, and the central axis side of the adjacent sliding body in the circumferential direction that pivots each of the multiple arms is positioned to be able to contact the side opposite to the central axis side of the gripping portion. As a result, as each of the multiple sliding bodies advances toward the central axis of the chuck body, the side of the gripping portion of each of the multiple sliding bodies that pivots it toward the central axis is pushed forward by the adjacent sliding body in the circumferential direction, causing each of the multiple arms to rotate toward the central axis around the portion pivoted by the sliding body, resulting in a movement similar to a so-called iris diaphragm mechanism. Therefore, since the workpiece rotates and moves along the central axis of each of the multiple arms' gripping parts and is gripped in contact with the optimal contact position of each of the multiple arms' gripping parts, the workpiece can be firmly held regardless of its cross-sectional shape. Consequently, when processing irregularly shaped workpieces, there is no need for workpiece processing work to firmly hold each irregularly shaped workpiece in the chuck, thus increasing the work efficiency when processing irregularly shaped workpieces. [Brief explanation of the drawing]

[0008] [Figure 1] This is a perspective view of a chuck according to Embodiment 1 of the present invention. [Figure 2] This is a plan view of the chuck according to Embodiment 1. [Figure 3] This is a cross-sectional view of the chuck according to Embodiment 1, taken along line AA in Figure 2. [Figure 4] The arm according to Embodiment 1 is shown, with (A) being a perspective view and (B) being a cross-sectional view. [Figure 5] The operation of the chuck according to Embodiment 1 is shown, where (A) is a plan view of a part of the chuck showing the state immediately before it holds the workpiece, and (B) is a diagram showing an example of a workpiece. [Figure 6] The operation of the chuck according to Embodiment 1 is shown, where (A) is a plan view of a part of the chuck showing it holding a workpiece, and (B) is a plan view of a part of the chuck showing it holding another workpiece. [Figure 7] This is a perspective view of a chuck according to Embodiment 2 of the present invention. [Figure 8] This is a cross-sectional view of a part of the chuck according to Embodiment 2. [Figure 9] This is a perspective view of a chuck and chuck handle according to Embodiment 3 of the present invention. [Figure 10] The chuck handle according to Embodiment 3 is shown, where (A) is a side view, (B) is a top view, and (C) is a cross-sectional view. [Figure 11] This is a perspective view of the chuck and positioning jig according to Embodiment 3. [Figure 12] This is a side view of the chuck and positioning jig according to Embodiment 3. [Modes for carrying out the invention]

[0009] (Embodiment 1) Hereinafter, a chuck according to an embodiment of the present invention will be described with reference to the drawings. The chuck according to this embodiment comprises a chuck body, a plurality of slide bodies disposed on the chuck body so as to be slidable along a plurality of virtual axes extending radially from the central axis of the chuck body in a direction perpendicular to the central axis, passing through a workpiece holding position on the chuck body where the workpiece to be held is placed, a plurality of arms having a gripping portion arranged so as to surround the central axis of the chuck body and curved so as to be recessed on the side facing the central axis, and a pivoted portion that is continuous with the base end of the gripping portion and pivotally supported on each of the plurality of slide bodies so as to be rotatable. The plurality of arms are arranged such that the tip of the gripping portion of each arm faces the central axis side of the gripping portion of the adjacent arm in the circumferential direction around the central axis, and the central axis side of the adjacent sliding body in the circumferential direction to the sliding body that pivots each arm is positioned so as to be able to abut against the side opposite to the central axis side of the gripping portion.

[0010] As shown in Figures 1 and 2, the chuck 1 according to this embodiment comprises a chuck body 131, three sliding bodies 132, and three arms 134. The chuck body 131 is a bottomed cylindrical shape and has an outer shell 1311 with an opening 1311a in its bottom wall as shown in Figure 3, and a disc-shaped rotating disc 1312 that is positioned inside the outer shell 1311 and is rotatable relative to the outer shell 1311. A spiral scroll groove 1312a is formed on the +Z direction side of the rotating disc 1312, centered on the central axis J1 of the chuck body 131.

[0011] Furthermore, the chuck body 131 includes a support block 1314 inserted through the opening 1311a of the outer shell 1311 and supporting the turntable 1312 so that it can rotate around the central axis J1 of the chuck body 1311, a cover plate 1315 arranged to cover the turntable 1312 on the +Z direction side and fixed to the +Z direction end of the support block 1314, and a rotating member 1313 that rotates in conjunction with the turntable 1312. The support block 1314 includes a base portion 13141 whose tip is inserted through the opening 1311a of the outer shell 1311, and a support portion 13142 having an outer flange portion 13142a that protrudes outward from the side wall perpendicular to the Z-axis direction and supports the turntable 1312 so that it can rotate when the turntable 1312 is placed on the +Z direction side of the outer flange portion 1314a. The base portion 13141 has a screw hole 13141b through which a screw 1317 is screwed in for fastening the support portion 13142 and the cover plate 1315 to the base portion 13141. The support portion 13142 also has a through hole 13142b that penetrates the support portion 13142 in the Z-axis direction and through which the screw 1317 is inserted. With the base end of the support portion 13142 fixed to the tip of the base portion 13141, the outer circumference of the opening 1311a of the outer shell body 1311 is positioned opposite the outer flange portion 13142a in the -Z direction. Furthermore, the base portion 13141 has an outer flange portion 13141a that protrudes outward from the side wall perpendicular to the Z-axis direction, and a wave spring 1316 that supports the outer shell 1311 is interposed between the outer circumference of the opening 1311a of the outer shell 1311 and the outer flange portion 13141a.

[0012] The cover plate 1315 is substantially circular in plan view, and as shown in FIGS. 1 and 2, three slits 1315a extending along three virtual axes J21, J22, and J23 that radially extend from the central axis J1 of the chuck body 131 are formed. As shown in FIG. 3, a sliding body 132 is inserted into each slit 1315a. Further, a pin mounting hole 1315b into which a pin 137 is inserted is formed in the cover plate 1315, and the pin 137 is fixed such that the end portion on the -Z direction side thereof is inserted into the pin mounting hole 1315b and the end portion on the +Z direction side protrudes to the +Z direction side of the cover plate 1315.

[0013] The rotating member 1313 has a cylindrical rotating member main body 13131 whose end portion on the -Z direction side is fixed to the peripheral portion of the rotating disk 1312, and an inner flange portion 13132 that projects inward from the end portion on the +Z direction side of the rotating member main body 13131. The rotating member 1313 is arranged to rise from the entire outer peripheral portion of the rotating disk 1312 to the +Z direction side and the end portion on the +Z direction side is exposed to the +Z direction side of the cover plate 1315.

[0014] As shown in Figures 1 and 2, the three sliding bodies 132 are slidably disposed on the chuck body 131 along three virtual axes J21, J22, and J23 that extend radially from the central axis J1, which passes through the workpiece holding position Pos1 where the workpiece to be held is positioned, in a direction perpendicular to the central axis J1. Each of the three sliding bodies 132 has an arm support portion 1321 and a hinge pin 1323. The arm support portion 1321 pivotally supports the arm 134 via the hinge pin 1323 so that it can rotate. Here, the arm support portion 1321 has a hinge groove 1321a formed on the side facing the central axis J1 and extending to the side facing the circumferential direction AR1, indicated by arrow AR1 in Figure 2, which circles around the central axis J1. The arm 134 is pivotally supported by a hinge pin 1323 with a portion of it fitted into a hinge groove 1321a, allowing it to rotate freely. The arm support portion 1321 is also provided with a through hole 1321b through which a screw 1324 is inserted, which penetrates the arm support portion 1321 in the Z-axis direction and secures the arm support portion 1321 to the sliding body 1322, which will be described later. The hinge pin 1323 may be fixed to the arm support portion 1321 or it may be detachable. If the hinge pin 1323 is detachable from the arm support portion 1321, the arm 134 can be detached from the arm support portion 1321 by detaching the hinge pin 1323 from the arm support portion 1321. This allows the arm 134, arm support portion 1321, and hinge pin 1323 to be cleaned separately, improving the workability when maintaining these parts.

[0015] Furthermore, each of the three sliding bodies 132 has a sliding body body 1322 with teeth 1322a protruding in the -Z direction, which are screwed into the scroll groove 1312a of the rotating disc 1312, as shown in Figure 3. The sliding body body 1322 has a screw hole 1322b for fixing the arm support portion 1321 to the sliding body body 1322 by a screw 1324. The arm support portion 1321 is fixed to the sliding body body 1322 by the tip of the screw 1324, which is inserted through the through hole 1321b, being screwed into the screw hole 1322b of the sliding body body 1322.

[0016] As shown in FIGS. 1 and 2, each of the three arms 134 has a gripping portion 1341 that is arranged to surround the central axis J1 of the chuck body 131 and is curved so that the central axis J1 side is recessed, and a pivotally supported portion 1342 that is continuous with the base end portion of the gripping portion 1341 and is pivotally supported on each of the plurality of sliders 132 so as to be rotatable. Here, each of the three arms 134 is arranged such that the tip end portion of the gripping portion 1341 faces the central axis J1 side of the gripping portion 1341 of the other arm 134 adjacent thereto in the circumferential direction AR1 that orbits around the central axis J1. Further, when viewed from the Z-axis direction, each of the three arms 134 is pivotally supported by a hinge pin 1323 at a portion located on the circumferential direction AR1 side of the virtual axes J21, J22, and J23 in the slider 132. As a result, with respect to each of the three arms 134, the central axis J1 side of the slider 132 that pivotally supports it and the other slider 132 adjacent thereto in the circumferential direction AR1 can abut on the opposite side of the central axis J1 side of the gripping portion 1341.

[0017] As shown in Figure 4(A), the gripping portion 1341 is a curved plate shape, with its thickness decreasing from the base end towards the tip. The tip of the gripping portion 1341 has a rounded shape when viewed from the Z-axis direction. As shown in Figure 4(B), the pivoted portion 1342 has a circular through-hole 1342a in plan view, and a hinge pin 1323 is inserted inside the through-hole 1342a. The sliding body 132 is provided with a biasing member 136 made of an elastic wire. The biasing member 136 has a winding portion 1361 that is spirally wound around the hinge pin 1323, an arm fixing portion 1362 that is continuous with one end of the winding portion 1361 and has an L-shaped bent tip fixed to the arm 134, and an extension portion 1363 that extends from the other end of the winding portion 1361 and is positioned to abut against the bottom surface 1321c of the hinge groove 1321a of the arm support portion 1321. When the arm 134 rotates so that the opening angle between the central axis J3 of the hinge pin 1323 and the tip portion Po2 of the arm 134 is different from a preset reference angle θ1, the biasing member 136 applies a biasing force to the arm 134 in a direction that causes the aforementioned opening angle to return to the reference angle θ1 due to its restoring force.

[0018] Next, the operation of the chuck according to this embodiment will be described. First, as shown in Figure 5(A), the workpiece W1 is positioned in a region surrounded by three arms 134A, 134B, and 134C, with the corner Pw11 of the workpiece W1 in contact with the arc portion of the gripping portion 1341 of one arm 134 on the side of the central axis J1. The workpiece W1 may also be positioned in contact with the arc portion of the gripping portion 1341 of any of the other two arms 134 on the side of the central axis J1. Here, the workpiece W1 is a long rectangular prism and has a first surface W1a and a second surface W1b along its longitudinal direction, as shown in Figure 5(B). At this time, the workpiece W1 is slidable relative to the chuck body 131 within the region surrounded by the three arms 134, as shown by the rectangular dashed line in Figure 5(A). Next, as the three sliding bodies 132 each slide toward the central axis J1 of the chuck body 131, the area surrounded by the three arms 134A, 134B, and 134C gradually shrinks. Then, as shown in Figure 6(A), the tip Po134a of arm 134A, which is in contact with the corner Pw11 of the workpiece W1, and the tip Po134a of arm 134B, which is adjacent to it in the circumferential direction, come into contact with the first surface W1a of the workpiece W1, and the tip Po134b of arm 134C, which is adjacent to arm 134B in the circumferential direction, come into contact with the second surface W1b of the workpiece W1. At this time, the resultant force F23 of the force F21 applied by arm 134A to the workpiece W1 and the force F22 applied by arm 134C to the workpiece W1 is equal to the force applied by arm 134B to the workpiece W1, and the workpiece W1 is gripped by the three arms 134A, 134B, and 134C with its corner Pw11 fixed at one point on the arc portion of the gripping part 1341 of arm 134A on the central axis J1 side. Here, the gripping state of the workpiece W1 by the three arms 134A, 134B, and 134C is maintained as long as the aforementioned rotating disc 1312 of the chuck body 131 does not rotate in the opposite direction to the rotation direction when the three sliding bodies 132 slide toward the central axis J1.

[0019] Furthermore, the chuck 1 according to this embodiment can firmly grip a workpiece W2 having a cross-sectional shape such as that shown in Figure 6(B). In this configuration, the workpiece W2 has two corners, Pw21 and PW22, with corner Pw21 in contact with arm 134A, the other corner Pw22 in contact with the tip Po134a of arm 134B which is adjacent to arm 134A in the circumferential direction, and the tip Po134b of arm 134C which is adjacent to arm 134B in the circumferential direction, in contact with the curved surface W2a of the workpiece W2. At this time, the resultant force F33 of the force F31 applied by arm 134A to workpiece W1 and the force F32 applied by arm 134C to workpiece W2 balances the force applied by arm 134B to workpiece W2, and workpiece W2 is gripped by the three arms 134A, 134B, and 134C with its corner Pw11 fixed at one point on the arc portion of the gripping part 1341 of arm 134A on the central axis J1 side.

[0020] As described above, according to the chuck 1 of this embodiment, the three arms 134 each have a gripping portion 1341 that is curved so as to be recessed on the side facing the central axis J1 of the chuck body 131, and a pivoted portion 1342 that is continuous with the base end of the gripping portion 1341 and pivotally supported by each of the three sliding bodies 132 so as to be rotatable. The three arms 134 are arranged so that the tip of the gripping portion 1341 faces the side facing the central axis J1 of the gripping portion 1341 of the other arm 134 that is adjacent to it in the circumferential direction. In addition, the three arms 134 are such that the side facing the central axis J1 of the other sliding body 132 that is adjacent to them in the circumferential direction can abut against the side opposite to the central axis J1 of the gripping portion 1341. As a result, as the three sliding bodies 132 advance toward the central axis J1 of the chuck body 131, the opposite side of the gripping portion 1341 of the arm 134 pivoted by each of the three sliding bodies 132 is pushed forward by the other sliding bodies 132 adjacent to it in the circumferential direction. This causes the three arms 134 to rotate toward the central axis J1 around the portion pivoted by the sliding body 132, resulting in a movement similar to a so-called iris diaphragm mechanism. Consequently, the workpiece W1 rotates or moves along the central axis J1 side of the gripping portion 1341 of each of the three arms 134 and is gripped in contact with the optimal contact position on the gripping portion 1341 of each of the three arms 134, thus firmly holding the workpiece W1 regardless of its cross-sectional shape. Therefore, when processing irregularly shaped workpieces W1, it is unnecessary to pre-process each irregularly shaped workpiece W1 to securely hold it in the chuck 1, thus increasing the work efficiency when processing irregularly shaped workpieces W1.

[0021] Incidentally, there has long been a type of chuck used to grip workpieces, known as a scroll chuck, which has an automatic self-aligning function. These scroll chucks are categorized as 3-jaw chucks, 4-jaw chucks, and 6-jaw chucks depending on the number of jaws that grip the workpiece. These chucks are used differently depending on the application, but all are based on the premise that the workpiece is cylindrical in shape. Therefore, for workpieces that are not cylindrical, such as those with a square, rectangular, trapezoidal, semicircular, or sector-shaped cross-section, these chucks may not be able to grip them firmly enough. In such cases, when gripping such workpieces, it has been common to use a fixing jig specifically designed for that workpiece according to its cross-sectional shape, or to use a special chuck in which multiple jaws slide independently. However, in this case, it is necessary to use multiple types of fixing jigs or special chucks depending on the type of workpiece, which can reduce work efficiency and increase the burden of preparation. Also, in the medical field, for example, in the treatment of avulsion fractures, bone fixation surgery is sometimes performed using screws made from metals such as titanium or materials with high affinity to biological tissue. In this bone fixation surgery, a method is being developed to reduce the burden on the patient by using bone from the patient with good bone fusion during the surgery, and then machining a screw of the optimal size for bone fixation. This eliminates the need for a second surgery to remove the screw after bone fusion. In this case, the shape of the bone material that can be harvested from the patient is not limited to cylindrical, depending on the condition of the patient's bone and the shape of their skeleton. For this reason, there is a risk that the conventional chuck described above may have difficulty firmly gripping the bone material. In contrast, the chuck 1 according to this embodiment can firmly grip workpieces of various cross-sectional shapes with the same operation as a conventional scroll chuck, without using a workpiece-specific fixing jig or individually preparing the jaws as described above. Therefore, for example, the time required to process the bone material harvested from the patient during bone fixation surgery can be shortened, reducing the burden on the doctor, and ultimately reducing the burden on the patient by shortening the overall time required for bone fixation surgery.

[0022] (Embodiment 2) The chuck according to this embodiment differs from the chuck according to Embodiment 1 in that multiple arms are pivotally supported on a single sliding body so as to be able to rotate freely.

[0023] As shown in Figure 7, the chuck 2001 according to this embodiment comprises a chuck body 131, three sliding bodies 2132, three arms 134, and three sub-arms 2134. In Figure 7, components similar to those in Embodiment 1 are denoted by the same reference numerals as in Figure 1. Each of the three sliding bodies 2132 has an arm support portion 21321 and a hinge pin 1323. The arm support portion 21321 pivotally supports the arms 134 and sub-arms 2134 via the hinge pin 1323 so that they can rotate freely. Here, the arm support portion 21321 has two hinge grooves 21321a that are arranged in parallel in the Z-axis direction and extend from the side facing the central axis J1 to the side facing the central axis J1, indicated by arrow AR1, on the circumferential AR1 side. Arm 134 is pivotally supported by a hinge pin 1323 with a portion of it fitted into one of the two hinge grooves 21321a located on the -Z side, allowing it to pivot freely. Sub-arm 2134 is also pivotally supported by a hinge pin 1323 with a portion of it fitted into the other of the two hinge grooves 21321a located on the +Z side, allowing it to pivot freely.

[0024] Each of the three sub-arms 2134 has a gripping portion 1341 that is arranged to surround the central axis J1 of the chuck body 131 and is curved so as to be recessed on the side facing the central axis J1, and a pivoted portion 21342 that is continuous with the base end of the gripping portion 1341 and pivotally supported on each of the multiple sliding bodies 2132 so as to be rotatable. Here, the tips of the gripping portions 1341 of each of the three sub-arms 2134 are arranged so as to face the central axis J1 side of the gripping portion 1341 of the adjacent sub-arm 2134 in the circumferential direction AR1 that rotates around the central axis J1. Also, when viewed from the Z-axis direction, each of the three sub-arms 2134 is pivotally supported by a hinge pin 1323 at a portion located one circumferential direction AR1 side of the virtual axes J21, J22, and J23 described in the embodiment of the sliding body 2132, similar to the arm 134. As a result, the three sub-arms 2134 are able to contact the central axis J1 side of each of the adjacent sliding bodies 2132 in one circumferential direction AR1 with the side opposite to the central axis J1 side of the gripping portion 1341.

[0025] As shown in Figure 8, an elongated hole 21342a is provided through the pivoted portion 1342 of the sub-arm 2134, and a hinge pin 1323 is inserted inside the elongated hole 21342a so as to be movable along the longitudinal direction of the elongated hole. This allows the sub-arm 2134 to move independently of the arm 134 when the three sliding bodies 2132 are slid toward the central axis J1 of the chuck body 131 to bring the three arms 134 into contact with the workpiece W3. Therefore, even if the cross-sectional shape of the portion of the workpiece W3 facing the three sub-arms 2134 is different from the cross-sectional shape of the portion gripped by the three arms 134, all three sub-arms 2134 can be brought into contact with the workpiece W3.

[0026] As described above, the chuck 2001 according to this embodiment allows the workpiece W3 to be gripped at multiple locations in the Z-axis direction, thus enabling a more secure grip on the workpiece W3.

[0027] (Embodiment 3) The chuck according to this embodiment differs from Embodiment 1 in that the chuck body has a rotating member which has a cylindrical rotating member body with one end in the axial direction of the cylinder fixed to the circumferential part of the rotating disk, and an inner flange portion which protrudes inward from the entire other end in the axial direction of the rotating member body and has a plurality of teeth formed over the entire tip portion.

[0028] As shown in Figure 9, the chuck 3001 according to this embodiment comprises a chuck body 3131 having a rotating member 31313. In Figure 9, components similar to those in Embodiment 1 are denoted by the same reference numerals as in Figure 1. The rotating member 31313 has a cylindrical rotating member body 313131 with its -Z-direction end fixed to the periphery of a rotating disc (not shown), and an inner flange portion 313132 that protrudes inward from the +Z-direction end of the rotating member body 313131. As described in Embodiment 1, the rotating disc is disc-shaped, positioned inside the outer shell 1311, and rotatable relative to the outer shell 1311. In addition, a plurality of teeth 313132a are formed over the entire tip of the inner flange portion 313132. Similar to Embodiment 1, the rotating member 31313 rises from the entire outer circumference of the rotating disc towards the +Z direction, and its +Z-direction end is exposed on the +Z-direction side of the cover plate 1315.

[0029] The rotating member 31313 of the chuck 3001 according to this embodiment can be rotated using the chuck handle 3005 and the rotation transmission member 3006. The rotation transmission member 3006 has a long shaft 3061, a gear 3062 provided at one end of the shaft 3061 in the longitudinal direction, and a hexagonal cross-section projection 3063 provided at the other end of the shaft 3061. When the gear 3062 is rotatably fitted to the tip of the pin 137 disposed on the chuck body 3131, it meshes with the teeth 313132a of the rotating member 31313 of the chuck body 3131.

[0030] As shown in Figures 10(A) to (C), the chuck handle 3005 comprises a long handle body 3052, a long gripping portion 3051 to be grasped by the user, a hinge pin 3054 connecting the handle body 3052 and the gripping portion 3051, and a long elastic member 3053. The tip of the handle body 3052 is provided with a through hole 3052a, which has a hexagonal shape in plan view and penetrates the handle body 3052. This through hole 3052a can be fitted into a projection 3063 of the rotation transmission member 3006. The elastic member 3053 is formed from an elastic metal such as β-titanium, and as shown in Figure 10(C), one end in the longitudinal direction is fixed to the hinge pin 3054 and the other end is locked by a stopper 3055 embedded in the handle body 3052.

[0031] Here, we will explain how to use the chuck handle 3005 and the rotation transmission member 3006. First, the gear 3062 of the rotation transmission member 3006 is engaged with the teeth 313132a of the rotating member 31313 of the chuck body 3131. Next, the through hole 3052a of the chuck handle 3005 is fitted into the projection 3063 of the rotation transmission member 3006. In this state, the gripping portion 3051 of the chuck handle 3005 is gripped and rotated. At this time, the elastic member 3053 gradually deforms so as to bend, and depending on the degree of deformation, the angle between the longitudinal direction of the handle body 3052 and the longitudinal direction of the gripping portion 3051 at the hinge pin 3054 becomes an angle that deviates from 180 degrees. The handle body 3052 is provided with 19 markings that reflect the difference between the angle between the longitudinal direction of the handle body 3052 and the longitudinal direction of the gripping portion 3051 and 180 degrees. This allows the torque applied to the rotation transmission member 3006 by the chuck handle 3005 to be visually observed, making it easier to adjust the torque applied to the rotation transmission member 3006 to an appropriate level.

[0032] Furthermore, the rotating member 31313 of the chuck 3001 according to this embodiment can also be rotated using the chuck handle 3005 while fixing the position of the workpiece W3 using a positioning jig 4007, as shown in Figures 11 and 12. The positioning jig 4007 has two long support columns 4074, a long shaft 4071, a gear 4072 provided at one end of the shaft 4071 in the longitudinal direction, and a hexagonal cross-sectional projection 4073 provided at the other end of the shaft 4071. The +Z direction ends of the two support columns 4074 are fitted to the tips of pins 137 disposed on the chuck body 3131. Also, when the gear 4072 is rotatably fitted to the tips of pins 137 disposed on the chuck body 3131, it meshes with the teeth 313132a of the rotating member 31313 of the chuck body 3131. Furthermore, the positioning jig 4007 has a plate 4075 that is supported at the +Z-direction ends of the two support columns 4074 and rotatably holds the shaft 4071. As shown in Figure 12, a cone-shaped rivet 4075a is provided in the center of the plate 4075, projecting toward the -Z direction.

[0033] When gripping the workpiece W3 with the chuck 3001, the tip of the rivet 4075a of the positioning jig 4007 is embedded in the end of the workpiece W3 on the +Z direction, thereby preventing the workpiece W3 from tilting.

[0034] Incidentally, particularly in the medical field, when cutting and processing bone material collected from patients, the bone material is sometimes held in a chuck. In this case, if the gripping force of the chuck on the bone material is excessive, there is a risk that the bone material may break. On the other hand, if the gripping force is insufficient, there is a risk that the bone material may fall out of the chuck during cutting and processing. In contrast, the chuck 3001 according to this embodiment allows the bone material to be held in the chuck 3001 using the aforementioned chuck handle 3005 and rotational transmission member 3006. Furthermore, as mentioned above, the torque applied to the rotational transmission member 3006 by the chuck handle 3005 can be visually observed. Therefore, regardless of the user's senses or experience, the chuck 3001 can grip the bone material with the necessary and sufficient gripping force, so even inexperienced users can properly perform the task of gripping the bone material in the chuck 3001.

[0035] Furthermore, by using the positioning jig 4007 according to this embodiment, it is possible to prevent the workpiece W3 from being unintentionally held in a tilted position by the chuck 3001.

[0036] Although embodiments of the present invention have been described above, the present invention is not limited to the configuration of the embodiments described above. For example, in each embodiment, there may be four or more sliding bodies 132, 2132, arms 134, and sub-arms 2134.

[0037] In each embodiment, an example was described in which the chuck body 131, 3131 is a so-called scroll chuck in which the sliding bodies 132, 2132 are slid by a rotating disc 1312. However, the means for sliding the sliding bodies 132, 2132 are not limited to those having a rotating disc 1312. For example, the chuck body may have a linear actuator, air cylinder, etc., that slides the sliding bodies 132, 2132 along virtual axes J21, J22, J23, respectively.

[0038] Although embodiments and variations of the present invention have been described above, the present invention is not limited thereto. The present invention includes embodiments and variations that are appropriately combined, and those that are appropriately modified thereto. [Industrial applicability]

[0039] The present invention is suitable as a chuck used when machining irregularly shaped workpieces. [Explanation of Symbols]

[0040] 1,2001,3001: Chuck, 131,3131: Chuck body, 132,2132: Sliding body, 134,134A,134B,134C: Arm, 136: Biasing member, 137: Pin, 1311: Outer shell, 1311a: Opening, 1312: Rotating disc, 1312a: Scroll groove, 1313: Rotating member, 1314: Support block, 1315: Cover plate T, 1315a: Slit, 1315b: Pin mounting hole, 1316: Wave spring, 1317, 1324: Screw, 1321b, 1342a, 3052a, 13142b: Through hole, 1321: Arm support part, 1321c: Bottom surface, 1322: Sliding body, 1322a: Teeth, 1322b, 13141b: Screw hole, 1323, 3054: Hinge pin, 132 1a,21321a: Hinge groove, 1341,3051: Gripping part, 1342,21342: Pivot part, 1361: Winding part, 1362: Arm fixing part, 1363: Extension part, 2134: Sub-arm, 3005: Chuck handle, 3006: Rotation transmission member, 3052: Handle body, 3053: Elastic member, 3061,4071: Shaft, 3062,4072: Teeth Car, 3063, 4073: projection, 4007: positioning jig, 4074: support column, 4075: plate, 4075a: rivet, 13131: rotating member body, 13132: inner flange, 13141: base, 13141a, 13142a: outer flange, 13142: support part, 21342a: elongated hole, J1: central axis, J21, J22, J23: virtual axis, Pos1: workpiece holding position

Claims

1. The zipper body and Multiple sliding bodies are disposed on the chuck body so as to be slidable along multiple virtual axes that extend radially from the central axis of the chuck body, passing through the workpiece holding position where the workpiece to be held is positioned, in a direction perpendicular to the central axis, The chuck body comprises a plurality of arms, each having a gripping portion that is arranged to surround the central axis and curved such that the side facing the central axis is recessed, and a pivoted portion that is continuous with the base end of the gripping portion and pivotally supported on each of the plurality of sliding bodies so as to be rotatable, Each of the multiple arms is arranged such that the tip of the gripping portion faces the central axis side of the gripping portion of another adjacent arm in one circumferential direction around the central axis, and the central axis side of the sliding body pivoting each of them and the other adjacent sliding body in the circumferential direction are arranged to abut against the side opposite to the central axis side of the gripping portion. Chuck.

2. The chuck body has a rotating disc with spiral scroll grooves inside, Each of the sliding bodies has teeth that screw into the scroll groove, and is capable of screwing along the virtual axis as the rotating disk rotates. The chuck according to claim 1.

3. The sliding body pivotally supports the arm via a hinge pin so that it can rotate freely. The arm and the hinge pin are detachably attached to the sliding body. The chuck according to claim 1 or 2.

4. When viewed from the direction of the central axis, the arm is pivotally supported at a portion of the sliding body located circumferentially to the virtual axis. The chuck according to claim 1 or 2.

5. The gripping portion is curved and plate-shaped, with a shape that becomes thinner as it approaches the tip from the base end. The chuck according to claim 4.

6. The tip of the gripping portion has a rounded shape when viewed from a direction along the central axis. The chuck according to claim 1 or 2.

7. The sliding body is detachably attached to the chuck body. The chuck according to claim 1 or 2.

8. The chuck body is further provided with a plurality of sub-arms, each having a gripping portion that is arranged to surround the central axis and curved such that the side facing the central axis is recessed, and a pivoted portion that is continuous with the base end of the gripping portion and pivotally supported on each of the plurality of sliding bodies so as to be rotatable, The sliding body, together with the arm, pivotally supports at least one of the sub-arms via a hinge pin so that it can rotate freely. The pivoted portion of the sub-arm has an elongated hole through which the hinge pin is inserted. The chuck according to claim 1 or 2.

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