Chuck device and method for attaching sub-jaw

Abstract

Provided are: a chuck device with which it is possible to lessen the burden of replacement work of child jaws attached to parent jaws and to achieve firm attachment of the child jaws to the parent jaws; and a method for attachment of child jaws.　The parent jaws of this chuck device each have: a recess provided so as to be recessed in a direction parallel to the axial center of a spindle; and a locking part that is disposed on the outer side of the recess in a direction orthogonal to the axial center. The child jaws each comprise: an elastic member; a biasing member having an insertion member that is to be inserted, by an elastic force of the elastic member, into the recess from a direction parallel to the axial center; a plate which, in a state of being attached to a corresponding one of the parent jaws, is disposed on the side opposite to the biasing member and which clamps said parent jaw in cooperation with the insertion member being inserted in the recess; and a to-be-locked part which, in a state where the insertion member is inserted in the recess, gets locked as a result of coming into contact with the locking part from the inner side in a direction orthogonal to the axial center.

Description

[Technical Field]

[0001] The present disclosure relates to a chuck device for gripping a workpiece and a method for attaching a sub-jaw. [Background technology]

[0002] Various chuck devices for gripping a workpiece have been proposed in the past. For example, Patent Document 1 below describes a chuck device for gripping an annular workpiece. In the chuck device of Patent Document 1, an annular workpiece is provided radially outward from the axis, and child jaws are arranged further radially outward from the workpiece. The child jaws are attached so as to be guided by the pins of the main jaws, and move radially inward in response to the radial advance / retract movement of the main jaws to press the workpiece. The workpiece is gripped between the multiple child jaws and the axis. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Utility Model Application Publication No. 01-166008 (Fig. 7) Summary of the Invention [Problem to be solved by the invention]

[0004] In the chuck device of Patent Document 1 mentioned above, a master jaw with a slave jaw attached thereto is operated to grip a workpiece with the slave jaw. In this type of chuck device, the slave jaw is replaced depending on the type of workpiece, etc. For this reason, it is desirable that the slave jaw has a structure that allows it to be easily attached to the master jaw. On the other hand, in order to press the workpiece with the slave jaw and stably grip it during rotation and processing of the workpiece, it is desirable that the slave jaw be firmly attached to the master jaw.

[0005] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a chuck device and a method for attaching a child jaw that can reduce the burden of replacing a child jaw attached to a parent jaw and can firmly attach the child jaw to the parent jaw. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, this specification provides a chuck comprising: a chuck body that rotates around the axis of a spindle; a stopper that is detachably attached to the chuck body; a master jaw that is attached to the chuck body; and a slave jaw that is detachably attached to the master jaw and that clamps a workpiece that is in contact with the stopper from the outside in a direction perpendicular to the axis, wherein the master jaw has a recess that is recessed in a direction parallel to the axis and a locking portion that is provided outside the recess in the direction perpendicular to the axis, and the slave jaw has an elastic member and a biasing member that has an insertion member that is inserted into the recess from a direction parallel to the axis by the elastic force of the elastic member, and when attached to the master jaw, the biasing member In a direction parallel to the axis, the main claw is sandwiched between a plate located on the opposite side and sandwiching the master claw between the plate and the insertion member inserted into the recess; and a locked portion that comes into contact with and is locked to the locking portion from the inside in a direction perpendicular to the axis when the insertion member is inserted into the recess. the master jaw has a recessed groove formed in a direction parallel to the axis, the plate has a ridge formed in a size that allows it to be inserted into the recessed groove, the recessed portion is formed at a position where the insertion member is inserted when the ridge is aligned with the position of the recessed groove and moved in a direction parallel to the axis, and the slave jaw is moved outward in a direction perpendicular to the axis from a state where the plate is positioned on the base end side of the chuck body with respect to the recessed groove, the master jaw has an attachment / detachment recessed portion inside the recessed portion in the direction perpendicular to the axis, the attachment / detachment recessed portion is recessed in a direction parallel to the axis, and is formed at a position where the insertion member is inserted when the ridge of the plate is aligned with the position of the recessed groove in the direction perpendicular to the axis. A chuck device is disclosed. Furthermore, the contents of the present disclosure are not limited to implementation as a chuck device, but are also useful when implemented as a method for attaching a sub-jaw to a chuck device. [Effects of the Invention]

[0007] According to the chuck device and the method of attaching a child jaw of the present disclosure, the burden of replacing a child jaw attached to a parent jaw can be reduced, and the child jaw can be firmly attached to the parent jaw. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view of an NC lathe according to an embodiment of the present invention. [Figure 2] FIG. [Figure 3] 3 is a cross-sectional view of the chuck device taken along line AA in FIG. 2 and a partially enlarged view thereof. [Figure 4] FIG. 4 is a cross-sectional view showing a state in which the metal plate has been removed from the attached state shown in FIG. 3. [Figure 5] FIG. [Figure 6] FIG. [Figure 7] FIG. [Figure 8] FIG. [Figure 9] FIG. 10 is a perspective view of the sub-claw as seen from the rear side. [Figure 10] FIG. [Figure 11] FIG. 10 is a perspective view showing a state in which the secondary jaw is inserted into the primary jaw in the axial direction. [Figure 12] 12 is a partial cross-sectional view of the side surface in the state of FIG. 11. [Figure 13] FIG. 12 is a rear view in the state of FIG. 11. [Figure 14] FIG. 10 is a perspective view showing a state in which a secondary claw is attached to a primary claw. [Figure 15] 15 is a partial cross-sectional view and a partial enlarged view of the side surface in the state of FIG. 14. [Figure 16] FIG. 15 is a rear view in the state of FIG. 14. DETAILED DESCRIPTION OF THE INVENTION

[0009] An embodiment of the chuck device of the present disclosure will be described below with reference to the drawings. FIG. 1 is a perspective view of an NC lathe 10. The NC lathe 10 is an example of an apparatus equipped with the chuck device of the present disclosure. In this embodiment, an example in which the chuck device of the present disclosure is embodied in a chuck device 11 of the NC lathe 10 will be described as an embodiment of the chuck device of the present disclosure. Note that the apparatus equipped with the chuck device of the present disclosure is not limited to an apparatus that automatically processes a workpiece, such as an NC lathe, but may also be a general-purpose lathe that is manually operated by a user to perform processing.

[0010] In the NC lathe 10, in addition to the chuck device 11 that grips the workpiece, a turret device that holds a tool and a drive mechanism (not shown) that moves the turret device along the X-axis, Z-axis, etc. are provided on the bed 13. The above-mentioned devices of the NC lathe 10 are covered by a main body cover 15. The main body cover 15 covers the upper part of the bed 13 of the NC lathe 10 and houses the above-mentioned devices. A sliding door 15A is provided at the center of the front of the main body cover 15. The sliding door 15A slides left and right in FIG. 1 to open and close the center of the front of the main body cover 15. A user can load or unload a workpiece by opening the sliding door 15A. Furthermore, as described below, a user can replace the stopper 22 and the sub-jaw 24 of the chuck device 11 by opening the sliding door 15A. FIG. 1 shows the sliding door 15A in an open state. The sliding door 15A may be opened and closed manually by the user or automatically by the NC lathe 10. The workpiece may be loaded and unloaded manually by the user or automatically by a loader. A control device 17 is provided next to the sliding door 15A on the front side of the main body cover 15. The control device 17 comprehensively controls the machining operations of the NC lathe 10.

[0011] When the sliding door 15A is opened, a space for machining a workpiece is formed inside the main body cover 15. The chuck device 11 is attached to the spindle of the NC lathe 10 in this machining space. The workpiece to be machined is gripped and rotated by this chuck device 11. The turret device, for example, selects a tool from a plurality of tools according to the machining content and performs machining on the workpiece gripped by the chuck device 11.

[0012] FIG. 2 shows an exploded perspective view of the chuck device 11. FIG. 3 shows a cross-sectional view of the chuck device 11 taken along line AA in FIG. 2 without being disassembled. In the following explanation, as shown in FIGS. 2 and 3, the direction along the axis of the spindle is referred to as the axial direction, and the direction perpendicular to the axial direction is referred to as the radial direction. In addition, the side of the chuck device 11 that is attached to the NC lathe 10 in the axial direction is referred to as the base end side, and the side to which the workpiece W (see FIG. 3) is attached is referred to as the tip end side. In addition, the explanation will be based on a state in which each member, such as the backing plate 22, is attached to the chuck body 21. Note that FIG. 3 shows a state in which the workpiece W is abutted (placed) against the backing plate 22 from the axial tip side.

[0013] As shown in Fig. 2, the chuck device 11 includes a chuck body 21, a contact member 22, a plurality of master jaws 23, and a plurality of slave jaws 24. The chuck body 21 has a generally cylindrical shape extending along the axis of the spindle, i.e., along the axial direction. The chuck body 21 is attached to a spindle 25. The spindle 25 rotates the chuck body 21 about its axis based on the rotation of a spindle motor (not shown).

[0014] (About the mounting structure of the 22nd plate) A tip end surface 21A is formed on the tip end side of the chuck body 21, to which the abutment 22 and the master jaw 23 are attached. The tip end surface 21A is circular, and a abutment attachment portion 27 is formed in the center, i.e., at a position along the axis. The abutment 22 is attached to the abutment attachment portion 27. The abutment 22 is generally annular in shape and is detachably attached to the abutment attachment portion 27 of the chuck body 21. A shank 27A is formed in the center of the abutment attachment portion 27 in the radial direction, i.e., at the position of the axis (center of rotation). The shank 27A has a cylindrical shape along the axial direction. The abutment 22 is formed with an insertion hole 22A into which the shank 27A is inserted. The insertion hole 22A is formed so as to penetrate the abutment 22 along the axial direction, has a circular cross-sectional shape, and has an inner diameter that matches the outer diameter of the shank 27A. When the abutment 22 is attached to the abutment attachment portion 27, the inner circumferential surface of the insertion hole 22A abuts against the outer circumferential surface of the shaft portion 27A. As a result, when the abutment 22 is attached to the abutment attachment portion 27, the abutment attachment portion 27 restricts radial movement of the abutment 22.

[0015] The backing metal mounting portion 27 has a first mounting surface 27B formed around the shank 27A. The first mounting surface 27B faces the tip end side of the chuck body 21 in a direction parallel to the axial direction and is a circular flat surface. The shank 27A is formed at the center of the first mounting surface 27B. The backing metal 22 has a second mounting surface 22B formed at the base end side of the backing metal 22. The second mounting surface 22B faces the base end side of the backing metal 22 in a direction parallel to the axial direction and is annular in shape with an insertion hole 22A formed in the center. The second mounting surface 22B comes into contact with the first mounting surface 27B when the backing metal 22 is mounted on the backing metal mounting portion 27 (chuck body 21). For example, the second mounting surface 22B is in surface contact with the entire first mounting surface 27B. As a result, when the abutment 22 is attached to the abutment attachment portion 27, the abutment attachment portion 27 restricts the abutment 22 from moving axially toward the base end side.

[0016] Furthermore, a positioning member 27C is provided on the first mounting surface 27B, protruding toward the tip in a direction parallel to the axial direction. The positioning member 27C is, for example, a bolt, which is screwed into a threaded portion formed on the first mounting surface 27B and is fixed to the first mounting surface 27B with its head protruding toward the tip. Note that the positioning member 27C is not limited to a bolt, and may be, for example, a metal member (metal protrusion) formed integrally with the backing metal mounting portion 27, or a pin.

[0017] Furthermore, the second mounting surface 22B is formed with a positioning hole 22C recessed from the base end side to the tip end side in a direction parallel to the axial direction. The positioning hole 22C is formed with a size that can accommodate the portion of the positioning member 27C that protrudes from the first mounting surface 27B toward the tip end. The positioning hole 22C accommodates the positioning member 27C when the abutment 22 is attached to the abutment mounting portion 27 and the second mounting surface 22B is in surface contact with the first mounting surface 27B. Note that the abutment 22 may not be in surface contact with the abutment mounting portion 27. In other words, the second mounting surface 22B and the first mounting surface 27B may be uneven or spherical instead of flat.

[0018] The abutment 22 is fixed to the abutment attachment portion 27 by a biasing member 29. More specifically, the biasing member 29 is attached to the abutment 22. The biasing member 29 is, for example, a ball plunger, and includes a spring 29A and a ball 29B biased by the elastic force of the spring 29A. The biasing member 29 is an example of the abutment-side biasing member of the present disclosure. Note that the abutment-side biasing member of the present disclosure is not limited to a ball plunger, and other plungers such as a pin plunger can also be used. Furthermore, the abutment-side biasing member is not limited to a plunger, and various biasing members (such as a leaf spring) that apply a biasing force from the abutment 22 to the main body-side recess 27D of the abutment attachment portion 27 (described later) can be used.

[0019] The biasing member 29 is attached to the abutment 22 with the ball 29B facing inward (toward the center in the radial direction) of the abutment 22. The biasing member 29 is attached to the abutment 22 in a position where the ball 29B is biased upward in FIG. 3 by a spring 29A. The biasing member 29 has, for example, a male thread formed on its outer circumferential surface, which is screwed into a threaded portion 22D (female thread) formed on the abutment 22 and fixed thereto. The radial position of the biasing member 29 relative to the abutment 22 is adjusted by the amount of screwing. Note that the abutment 22 has, for example, a horizontal hole 22E formed therein that communicates with the threaded portion 22D. A screw (not shown) is screwed into this horizontal hole 22E to prevent the biasing member 29 from loosening. The radial position of the biasing member 29 is more firmly fixed by this anti-loosening screw.

[0020] Further, the backing metal mounting portion 27 is formed with a main body side recess 27D into which the ball 29B of the biasing member 29 is inserted. The main body side recess 27D is, for example, a countersink (recess) formed by countersinking a portion of the metal backing metal mounting portion 27. The main body side recess 27D is formed by recessing the backing metal mounting portion 27 radially inward. The main body side recess 27D is formed to match the position of the biasing member 29. In other words, when the backing metal 22 is attached to the backing metal mounting portion 27 by aligning the positioning hole 22C with the position of the positioning member 27C, the main body side recess 27D is formed at a position where the ball 29B of the biasing member 29 is inserted.

[0021] (Regarding the installation of Allowance 22) FIG. 4 shows a state in which the contact 22 has been removed from the attached state shown in FIG. 3. Since FIG. 4 shows a state in which the contact 22 has been removed, the workpiece W in FIG. 3 is not shown. As shown in FIG. 4, the user attaches the contact 22 to the contact attachment portion 27 with the position of the positioning member 27C aligned with the positioning hole 22C. The user aligns the positioning member 27C with the positioning hole 22C and inserts the shaft portion 27A into the insertion hole 22A to attach the contact 22 to the contact attachment portion 27. By aligning the positioning member 27C with the positioning hole 22C, the biasing member 29 and the main body recess 27D are aligned in the circumferential direction. The user inserts the contact 22 into the contact attachment portion 27 until, for example, the biasing member 29 is inserted into the main body recess 27D and the user feels a sensation in their hand as if the ball 29B of the biasing member 29 is entering the main body recess 27D. The user inserts the biasing member 29 into the main body recess 27D, which facilitates the attachment of the abutment 22 and allows the abutment 22 to be attached to the abutment attachment portion 27 at the correct position where the biasing member 29 is inserted into the main body recess 27D.

[0022] As shown in the enlarged view of FIG. 3 , when the abutment 22 is attached to the abutment attachment portion 27, the center line O2 of the ball 29B is offset toward the distal end from the center line O1 of the recess (countersink) of the body-side recess 27D. The center line O1 is, for example, a straight line passing through the center of the countersink of the body-side recess 27D and parallel to the radial direction. The center line O2 is, for example, a straight line passing through the center of the spherical ball 29B and parallel to the radial direction. Therefore, the abutment 29 presses the ball 29B against the body-side recess 27D at a position distal to the center line O1 of the body-side recess 27D. The ball 29B is pressed against the inclined surface of the body-side recess 27D, which slopes radially inward from the distal end toward the proximal end. As a result, the abutment 22 receives a force (reaction force) biasing it toward the proximal end from the inclined surface of the body-side recess 27D.

[0023] Meanwhile, when the abutment 22 is attached to the abutment attachment portion 27, the second attachment surface 22B is in surface contact with the first attachment surface 27B from the tip side, and is locked by the first attachment surface 27B. Therefore, a portion of the first attachment surface 27B that faces the biasing member 29 in the axial direction functions as a main body side locking portion of the present disclosure. Furthermore, a portion of the second attachment surface 22B that contacts the first attachment surface 27B that functions as the main body side locking portion functions as abutment side locked portion of the present disclosure.

[0024] According to this, the abutment 22 is restricted from moving in the radial direction by sandwiching the shaft portion 27A from both radial sides between the inner wall of the insertion hole 22A and the ball 29B. Furthermore, with the ball 29B inserted into the main body recess 27D, the second mounting surface 22B of the abutment 22 contacts the first mounting surface 27B from the axial tip side. This restricts the abutment 22 from moving in the axial direction. Therefore, the abutment 22 can be firmly attached to the abutment mounting portion 27.

[0025] Furthermore, by shifting the center lines O1 and O2 and abutting the ball 29B against the inclined surface of the main body recess 27D, the ball 29B, biased by the spring 29A, tries to fit (submerge) toward the center (deeper) of the main body recess 27D. The abutment 22 receives a reaction force toward the base end from the inclined surface of the main body recess 27D via the ball 29B, and presses the second mounting surface 22B against the first mounting surface 27B. As a result, the abutment 22 is attached to the abutment mounting portion 27 while receiving a force toward the base end, and axial movement is restricted. The abutment 22 can be more firmly fixed to the abutment mounting portion 27 against rotation of the chuck body 21 during machining.

[0026] In addition, the abutment 22 can be attached by attaching the abutment 22 to the abutment attachment portion 27 from the axial tip end side and pushing the abutment 22 into a position where the ball 29B of the biasing member 29 fits into the main body side recess 27D (a position where the first and second attachment surfaces 27B, 22B are in surface contact). This allows the user to easily attach the abutment 22 to the abutment attachment portion 27 with a single touch.

[0027] Furthermore, when removing the contact metal 22, the contact metal 22 can be removed by pulling the contact metal 22 toward the tip end against the biasing force of the spring 29A until the ball 29B comes out of the main body recess 27D. Therefore, even during the removal operation, the user can easily remove the contact metal 22 with a single touch. This allows the contact metal 22 to be easily replaced with an appropriate one depending on the type of workpiece W, etc.

[0028] As described above, the radial position of biasing member 29 is adjusted by the amount of screwing. Therefore, the force with which ball 29B presses main body recess 27D by spring 29A can be adjusted in accordance with the screwing position of biasing member 29. This makes it possible to adjust the magnitude of the force required for installation, the fixing force after installation, and the force required for removal by adjusting the installation position of biasing member 29, i.e., the screwing position.

[0029] In this embodiment, the back metal mounting portion 27 and the back metal 22 include, for example, three combinations of the above-described body-side recesses 27D and biasing members 29. The three combinations of back metal mounting portions 27 and biasing members 29 are provided, for example, at equal intervals (120-degree intervals) around the circumferential direction of the back metal 22. Each of these three combinations of back metal mounting portions 27 and biasing members 29 is provided at a position where the ball 29B fits into the body-side recess 27D when the positioning member 27C is aligned with the positioning hole 22C. Note that the chuck device 11 may be configured to include only one combination of the body-side recesses 27D and biasing members 29, or may be configured to include two or more combinations. Furthermore, the back metal 22 may be configured to be fixed to the back metal mounting portion 27 with bolts and nuts without using the biasing members 29. In this case, the back metal mounting portion 27 does not need to include the body-side recess 27D. Although details are omitted, the backing plate mounting portion 27 and the master jaw 23 are formed with a detection hole 30 for blowing compressed air to check whether the workpiece W is properly attached (seated) on the backing plate 22. The NC lathe 10 can determine the seating state of the workpiece W based on the back pressure of the compressed air sent into the detection hole 30.

[0030] (Installation structure of sub-claw 24) Next, the attachment structure of the child jaws 24 to the parent jaws 23 will be described. As shown in FIGS. 2 and 3, three jaw attachment portions 33 are provided on the tip surface 21A of the chuck body 21. A parent jaw 23 is attached to each of the three jaw attachment portions 33. A child jaw 24 is attached to each of the three parent jaws 23. Therefore, the chuck device 11 of this embodiment has three combinations of jaw attachment portions 33, parent jaws 23, and child jaws 24. Each of the three sets of jaw attachment portions 33, parent jaws 23, and child jaws 24 has the same shape and structure. Therefore, the following description will describe any one set of jaw attachment portions 33, etc. Note that each set of jaw attachment portions 33, parent jaws 23, and child jaws 24 may have a different structure from each other. Furthermore, the number of sets of jaw attachment portions 33, etc. is not limited to three, and may be multiple sets other than one or three.

[0031] The three jaw attachment portions 33 are provided at equal intervals (120-degree intervals) in the circumferential direction of the chuck body 21. Accordingly, the master jaws 23 and the slave jaws 24 are also provided at equal intervals (120-degree intervals) in the circumferential direction. A stopper 22 is disposed at the center of the three slave jaws 24, against which the workpiece W (see FIG. 3) is pressed. Each of the three slave jaws 24 moves radially, clamping the workpiece W abutted against the stopper 22 between them and chucking (fixing) the workpiece W in a machineable state. More specifically, for example, the jaw attachment portions 33, master jaws 23, and slave jaws 24 form a so-called ball chuck, which swings around a rotation center O3 shown in FIG. 3 in response to the driving force of a drive mechanism (not shown). The jaw attachment parts 33 and the like rotate (swing) clockwise around a rotation center O3 in Fig. 3 to clamp the workpiece W, and rotate counterclockwise to release the chuck (see the two-dot chain line in Fig. 3). The rotation center O3 is, for example, the center of a ball (not shown) provided in the chuck body 21. Note that the jaw attachment parts 33 and the like are not limited to a ball chuck, and may be configured to slide radially without swinging.

[0032] The master claw 23 is fixed to the claw attachment portion 33 by, for example, two bolts 35, and swings integrally with the claw attachment portion 33. For example, a T-slot nut 37 is attached to the claw attachment portion 33, and the bolt 35 is threaded into this T-slot nut 37 to fix the master claw 23 to the claw attachment portion 33. A gap (space) corresponding to the height of the T-slot nut 37 is formed between the master claw 23 and the claw attachment portion 33 in the axial direction. First and second plates 54, 55 of the secondary claw 24, which will be described later, are inserted into this gap. Note that the member forming the gap between the master claw 23 and the claw attachment portion 33 is not limited to a T-slot nut, and may be a nut of another shape, a washer, a spring, or the like.

[0033] FIG. 5 shows a front view of the master jaw 23 as seen from the tip end in the axial direction. In the following explanation, the master jaw 23 will be described based on the left-right direction as seen from the front of the chuck device 11 in the axial direction, as shown in FIG. 5. This left-right direction is, for example, a direction parallel to a line (a line tangential to the cylindrical chuck body 21) perpendicular to a radial line passing through the axis of the chuck body 21 and the center of the master jaw 23. As shown in FIGS. 5, 6, and 7, the master jaw 23 has a main body portion 39 and a locking portion 41. The master jaw 23 has a shape that is line-symmetrical with respect to a line 40 that passes through the center of the master jaw 23 in the left-right direction and runs along the radial direction. The main body portion 39 has a predetermined thickness in the axial direction and has a generally rectangular plate shape that is elongated in the radial direction when viewed from one side in the axial direction.

[0034] Four grooves 43 are formed on both sides of the main body 39 in the left-right direction. Two of the four grooves 43 are formed on the left side surface and two on the right side surface of the main body 39. The four grooves 43 are formed by recessing the main body 39 toward the inside in the left-right direction, and are grooves formed along a direction parallel to the axial direction. The cross-sectional shape of each groove 43 cut by a plane perpendicular to the axial direction is a rectangle that is long in the radial direction. The two grooves 43 formed on one side surface in the left-right direction are formed parallel to each other with a predetermined gap between them in the radial direction.

[0035] Two L-shaped grooves 44 are formed at the inner end of the master jaw 23, at positions radially inward of the grooves 43. The two L-shaped grooves 44 are formed radially inward of the grooves 43 formed on both left and right sides. Each of the four grooves 43 and the two L-shaped grooves 44 is formed to a size that allows the ridges 54A, 55A (see FIG. 9) of the slave jaw 24, which will be described later, to be inserted therein. A distal end surface 43A of the grooves 43 is flush with a distal end surface 39A of the main body 39 (see FIG. 7). The grooves 43, excluding their bottom portions, protrude further toward the base end than a proximal end surface 39B of the main body 39, forming a flat surface on the distal end surface 43B (see FIG. 7).

[0036] The main body 39 also has two bolt holes 45 formed in the left-right center with a predetermined radial distance between them. The two bolt holes 45 axially penetrate the main body 39, and each of the two bolts 35 described above is inserted into one of the bolt holes 45. Note that the bolts 35 are not shown in FIGS. 6 and 7. The main body 39 also has two recesses 47 and two attachment / detachment recesses 48. The recesses 47 and the attachment / detachment recesses 48 are, for example, countersink holes (recesses) formed by countersinking a portion of the metal main body 39. The two recesses 47 and the two attachment / detachment recesses 48 each have, for example, the same shape and are formed by recessing the main body 39 toward the base end in the axial direction. The recesses 47 and the attachment / detachment recesses 48 are inserted into a biasing member 57 of the secondary jaw 24, which will be described later.

[0037] The two recesses 47 are formed at positions sandwiching the radially outer bolt hole 45 of the two bolt holes 45 in the left-right direction. Similarly, the two attachment / detachment recesses 48 are formed at positions sandwiching the radially outer bolt hole 45 in the left-right direction, and at positions radially inward of the recesses 47. The distance L1 between the two recesses 47 in the left-right direction is the same as the distance between the two attachment / detachment recesses 48 in the left-right direction. In addition, the recesses 47 and the attachment / detachment recesses 48 are formed at positions spaced a predetermined distance L2 apart in the radial direction. The recesses 47 are formed at positions into which the biasing member 57 (see FIG. 9) of the secondary claw 24 is inserted when the secondary claw 24 is attached to the primary claw 23, as will be described later. In addition, the attachment / detachment recess 48 is formed at a position where the urging member 57 is inserted when the child claw 24 is removed from the parent claw 23 (when the protrusions 54A, 55A of the first and second plates 54, 55 described later are inserted into the recessed groove 43 and the L-shaped groove 44).

[0038] The locking portion 41 is located radially outside the two recesses 47 and is integrally formed with the outer end of the main body 39 in the radial direction. The locking portion 41 has a generally plate-like shape that is thin in the radial direction and protrudes from the main body 39 toward the tip. The locking portion 41 is formed from one end of the main body 39 to the other end in the left-right direction. A first flat surface 41A is formed on the radially inner side of the locking portion 41. The first flat surface 41A is a flat surface that extends in the left-right and axial directions and comes into contact with a second flat surface 51E (see FIG. 9) of the child claw 24, which will be described later.

[0039] 8 and 9, the child jaw 24 has a main body 51, a first side portion 52, a second side portion 53, a first plate 54, a second plate 55, and two biasing members 57. The child jaw 24 is configured to be detachable from the parent jaw 23. When attached to the parent jaw 23, the child jaw 24 swings integrally with the claw attachment portion 33 and the parent jaw 23, and clamps the workpiece W (see FIG. 3) abutted against the abutment 22 from the outside in the radial direction. The child jaw 24 has a shape and structure that is symmetrical with respect to a straight line 65 (see FIG. 8) that passes through the center in the left-right direction and is parallel to the radial direction.

[0040] The main body 51 is plate-shaped with a predetermined thickness in the axial direction. When viewed in the axial direction, the radially outer portion of the main body 51 has a rectangular shape that is long in the left-right direction, and an inner convex portion 51A is formed on the radially inner portion of the main body 51. The inner convex portion 51A protrudes toward the tip end in the axial direction (see FIG. 10) and has a shape that curves radially outward. Two clamping claws 59 are attached to the radially inner surface of the inner convex portion 51A, i.e., the curved surface 51B. Each of the two clamping claws 59 is fixed to the inner convex portion 51A by two bolts 61 (see FIG. 10) inserted radially from the outside into the inner convex portion 51A. The clamping claws 59 are provided with, for example, a plurality of mountain-shaped protrusions with pointed tips. The clamping claws 59 clamp the workpiece W by abutting these protrusions against the workpiece W.

[0041] The first side portion 52 is formed on the right end of the main body portion 51. The first side portion 52 is formed integrally with the main body portion 51 and protrudes toward the base end in the axial direction. The first side portion 52 is a plate-shaped member having a predetermined thickness in the left-right direction and approximately the same length as the main body portion 51 in the radial direction. A first plate 54 is attached to a tip surface 52A on the base end side of the first side portion 52. The first plate 54 is fixed to the tip surface 52A by two bolts 63 inserted from the base end side in the axial direction.

[0042] Three ridges 54A are formed on the inner side (left side) of the first plate 54 in the left-right direction. The multiple ridges 54A protrude leftward from the left side surface of the first plate 54, protrude further left than the left side surface of the first side portion 52, and are formed with a predetermined interval between them in the radial direction. The ridges 54A have a generally rectangular parallelepiped shape that is long in the axial direction. The length L3 of the ridges 54A in the radial direction is, for example, slightly shorter than the length L4 (groove width, see FIG. 7) of the groove 43 in the radial direction. Therefore, the ridges 54A are formed to a size that allows them to be inserted into the groove 43. Of the multiple ridges 54A, the two ridges 54A on the outer side in the radial direction are formed to match the position of the groove 43 formed on the right side of the master claw 23 and are inserted into this groove 43. The radially innermost ridge 54A is formed to match the position of the L-shaped groove 44 formed on the right side of the master claw 23 and is inserted into this L-shaped groove 44. The radially innermost ridge 54A may have a length L3 different from the other ridges 54A.

[0043] As described above, the secondary jaw 24 has a shape and structure that is symmetrical with respect to the straight line 65. Therefore, detailed description of the second side portion 53 and the second plate 55 will be omitted. The second side portion 53 is formed on the left end of the main body 51 and protrudes toward the base end. The second plate 55 is fixed to the tip surface 53A of the second side portion 53 by two bolts 67. Similar to the protruding strip 54A, three protruding strips 55A are formed on the right side of the second plate 55. Therefore, the protruding strips 54A, 55A protrude toward each other in the left-right direction. The three protruding strips 55A are inserted into the two recessed grooves 43 and the L-shaped groove 44 formed on the left side of the primary jaw 23.

[0044] A space is formed on the base end side of the secondary jaw 24 in the axial direction, surrounded by the main body 51, the first and second side portions 52, 53, and the first and second plates 54, 55. The primary jaw 23 is housed in this space when the secondary jaw 24 is attached. The distance L5 in the axial direction between the first and second plates 54, 55 (the ridges 54A, 55A) and the main body 51 is, for example, approximately the same as the distance L6 (see FIG. 7) between the surface 39A on the tip side of the primary jaw 23 and the surface 43B of the recessed groove 43 in the axial direction.

[0045] The two urging members 57 are attached to the radially outer portion of the main body 51. The two urging members 57 are provided at the same position in the radial direction, are arranged symmetrically across the straight line 65, and are provided at positions spaced a predetermined distance L7 apart in the left-right direction. This distance L7 is the same as the distance L1 (see FIG. 5) between the recess 47 and the attachment / detachment recess 48. That is, the urging members 57 are attached in accordance with the positions of the recess 47 and the attachment / detachment recess 48.

[0046] The biasing member 57 is, for example, a ball plunger, and includes a spring 57A and a ball 57B that is biased by the elastic force of the spring 57A (see FIGS. 3 and 12). Note that the biasing member of the present application is not limited to a ball plunger, and other plungers such as a pin plunger can also be used. Furthermore, the biasing member is not limited to a plunger, and various biasing members that apply a biasing force from the child jaw 24 to the main jaw 23 can also be used.

[0047] The biasing member 57 is attached to the main body 51 with the ball 57B facing the base end side (the master claw 23 side) in the axial direction. The biasing member 57 has, for example, a male thread formed on its outer peripheral surface, which is screwed into a threaded portion 51C (female thread) formed on the main body 51 and fixed thereto. The position of the biasing member 57 relative to the main body 51 in the axial direction is adjusted by the amount of screwing. Note that, for example, a horizontal hole 51D communicating with the threaded portion 51C is formed in the radial outer surface of the main body 51 (a second flat surface 51E described later). A screw (not shown) is screwed into this horizontal hole 51D to prevent the biasing member 57 from loosening.

[0048] Furthermore, a second flat surface 51E is formed on the radially outer side of the main body 51. The second flat surface 51E is, for example, a flat surface along the axial direction and the left-right direction, and has a rectangular shape with a predetermined width in the axial direction and a long width in the left-right direction. When the secondary claw 24 is attached to the primary claw 23, the second flat surface 51E comes into surface contact with and is locked to the first flat surface 41A of the locking portion 41 of the primary claw 23. Therefore, the portion of the main body 51 where the second flat surface 51E is formed functions as the locked portion of the present disclosure.

[0049] (Installation of the 24 sub-claw) Fig. 10 is an exploded perspective view of the master claw 23 and the slave claw 24. As shown in Fig. 10, the user positions the slave claw 24 and the master claw 23 facing each other in a direction parallel to the axial direction, with the ridges 54A, 55A of the first and second plates 54, 55 aligned with the recessed grooves 43 and the L-shaped grooves 44, respectively. With the slave claws positioned facing each other, the user attaches the slave claw 24 to the master claw 23 from the tip end in the axial direction (see the arrow in Fig. 10). As the slave claw 24 is moved toward the base end, the ridges 54A, 55A are inserted into the recessed grooves 43 and the L-shaped grooves 44, respectively.

[0050] As shown in FIGS. 11 to 13, when the ridges 54A and 55A are inserted into the groove 43 and the L-shaped groove 44, the two attachment / detachment recesses 48 are positioned to face the balls 57B of the two biasing members 57 in the axial direction. The user inserts the secondary claw 24 into the primary claw 23 until the ridges 54A and 55A are positioned on the axially proximal side of the surface 43B of the groove 43. For example, the user inserts the secondary claw 24 until the distal end surface 39A of the primary claw 23 abuts against the axially proximal surface of the main body 51, the ball 57B abuts against the attachment / detachment recess 48, and the biasing force of the biasing member 57 is felt by hand. In this state, the center line O4 of the depression of the attachment / detachment recess 48 coincides with the center line of the ball 57B (see FIG. 12). Because the surface 43B and the ridges 54A and 55A are positioned at radially offset positions (see FIG. 13), the secondary claw 24 can be freely moved in the axial direction relative to the primary claw 23, i.e., removed. The ridges 54A and 55A are inserted into an axial gap between the primary claw 23 and the claw mounting portion 33, formed by, for example, the T-slot nut 37. The second flat surface 51E of the main body 51 and the first flat surface 41A of the locking portion 41 are positioned opposite each other with a predetermined radial gap therebetween. This gap is, for example, the same as the distance L2 (see FIG. 5) between the recess 47 and the attachment / detachment recess 48.

[0051] 11 to 13, the user moves the secondary claw 24 radially outward relative to the primary claw 23 (see the arrow in FIG. 11). When the ball 57B comes out of the attachment / detachment recess 48 as the secondary claw 24 moves, the biasing force of the spring 57A presses the primary claw 23 (surface 39A) toward the base end in the axial direction with the ball 57B. In addition, the ridges 54A and 55A of the first and second plates 54 and 55 are positioned so as to overlap the base end of the surface 43A of the recessed groove 43 in the axial direction. Therefore, the main body 39 of the primary claw 23 is sandwiched between the ridges 54A and 55A and the two biasing members 57 in the axial direction.

[0052] As shown in FIGS. 14 to 16 , the user moves the child jaw 24 radially outward to a position where the ball 57B of the biasing member 57 is inserted into the recess 47. When the biasing member 57 is moved radially outward from the position where the ball 57B is inserted into the attachment / detachment recess 48 by a distance L2 (see FIG. 5 ) or a distance slightly shorter than the distance L2, the ball 57B is inserted into the recess 47. The child jaw 24 axially contacts the protruding ridges 54A and 55A with the surface 43A from the base end side and the main body 51 with the surface 39A from the tip end side, inserting the ball 57B into the recess 47 and sandwiching the child jaw 23 in the axial direction. Therefore, when the child jaw 24 is attached to the child jaw 23, the first and second plates 54 and 55 are located on the opposite side of the biasing member 57 in the axial direction, and sandwich the child jaw 23 between them and the ball 57B inserted into the recess 47. The secondary claw 24 is now restricted from moving in the axial direction relative to the main claw 23. The user moves the secondary claw 24 until, for example, the user feels as if the ball 57B is entering the recess 47. This makes it easier to attach the secondary claw 24, and the secondary claw 24 can be attached to the main claw 23 in the correct position where the biasing member 57 is inserted into the recess 47.

[0053] As described above, the child jaw 24 is moved in a direction parallel to the axial direction with the ridges 54A, 55A aligned with the recessed groove 43, and then moved radially outward from a state in which the ridges 54A, 55A are positioned on the base end side of the surface 43B of the recessed groove 43. As a result, the recess 47 is formed at a position where the ball 57B of the biasing member 57 is inserted. With this configuration, the child jaw 24 can be attached by moving it axially from a position where it faces the main jaw 23 in the axial direction, and then moving it radially. This eliminates the need to position the entire child jaw 24 radially inward of the main jaw 23.

[0054] Alternatively, the entirety of the child jaw 24 may be positioned radially inward of the parent jaw 23, for example, at a position where the second flat surface 51E is closer to the abutment 22 than the main body 39, and then the child jaw 24 may be moved radially outward to sandwich the parent jaw 23 between the ridges 54A and 55A and the abutment 22, and then the abutment 57 may be inserted into the recess 47 for attachment. In this case, the parent jaw 23 does not need to have the recessed groove 43, the L-shaped groove 44, or the attachment / detachment recess 48. However, since the child jaw 24 is positioned inside the parent jaw 23, it is necessary to provide a space between the parent jaw 23 and the abutment 22 in the radial direction so that the child jaw 24 can be inserted. In other words, the radial distance between the parent jaw 23 and the abutment 22 becomes longer. As a result, the entire chuck device 11 (e.g., the radial length) becomes longer.

[0055] In contrast, as described above, by providing the recessed groove 43 or the like and configuring the device so that the child jaws 24 can be inserted from the axial direction, it is possible to facilitate the attachment work of the child jaws 24 while miniaturizing the chuck device 11. Note that the content of the present disclosure may also be configured so that the child jaws 24 are attached from the radially inner side of the parent jaw 23 (a configuration that does not require axial attachment work). In this case, as described above, the parent jaw 23 does not need to be provided with the recessed groove 43, the L-shaped groove 44, the attachment / detachment recess 48, or the like. Also, the first and second plates 54, 55 may not have a convex shape like the ridges 54A, 55A, but may have a shape that fills the gaps between the ridges 54A, 55A (a single plate shape).

[0056] As shown in the enlarged view of FIG. 15 , when the secondary jaw 24 is attached to the primary jaw 23, the biasing member 57 is configured such that the center line O6 of the ball 57B is offset radially inward from the center line O5 of the depression (countersink) of the recess 47. The center line O5 is, for example, a straight line passing through the center of the recess 47, which is a countersink, and is parallel to the axial direction. The center line O6 is, for example, a straight line passing through the center of the spherical ball 57B and is parallel to the axial direction. Therefore, the biasing member 57 presses the ball 57B against the recess 47 at a position radially inward of the center line O5 of the recess 47. The ball 57B is pressed against the inclined surface of the recess 47, which slopes radially outward from the radially inward direction. As a result, the secondary jaw 24 receives a force (reaction force) biasing it radially outward from the inclined surface of the recess 47.

[0057] Meanwhile, when the child claw 24 is attached to the parent claw 23 (with the ball 57B inserted in the recess 47), the second flat surface 51E is in surface contact with the first flat surface 41A from the radially inner side, and is locked. Therefore, the portion of the main body 51 located radially outward from the biasing member 57 functions as the locked portion of the present disclosure. By shifting the center lines O5 and O6 and abutting the ball 57B against the inclined surface of the recess 47, the ball 57B, biased by the spring 57A, attempts to fit toward the center of the recess 47. The child claw 24 receives a radially outward reaction force from the inclined surface of the recess 47 via the ball 57B, and presses the second flat surface 51E against the first flat surface 41A. As a result, the child claw 24 is attached to the parent claw 23 while receiving a radially outward force, and its radial movement is restricted.

[0058] If the center lines O5 and O6 were aligned, the ball 57B would be positioned at the bottom of the countersink in the recess 47. In this case, the biasing force of the spring 57A on the ball 57B would be balanced with the reaction force from the bottom of the countersink. In other words, unlike when the ball 57B is positioned on the inclined surface described above, no force is applied to push the ball 57B radially outward (toward the bottom of the inclined surface). As a result, the ball 57B may move radially inward during machining of the workpiece W, which may cause the secondary jaw 24 to move or vibrate, generating abnormal noise. In contrast, by positioning the ball 57B on the inclined surface described above, the radial movement of the ball 57B can be suppressed, thereby suppressing the generation of abnormal noise.

[0059] Furthermore, the child claw 24 is attached to the parent claw 23 with the second flat surface 51E in surface contact with the first flat surface 41A of the locking portion 41. This allows the child claw 24 to be more stably locked by the parent claw 23, and the child claw 24 can be firmly fixed to the parent claw 23. Note that the child claw 24 may not be in surface contact with the parent claw 23. In other words, the second flat surface 51E and the first flat surface 41A may not be flat, but may be uneven or spherical.

[0060] The master jaw 23 is housed in a space surrounded by the main body 51, the first and second side portions 52, 53, and the first and second plates 54, 55. The side surfaces of the master jaw 23 in the left-right direction, i.e., the surfaces of the non-recessed portions of the recessed groove 43, are in close contact with the inner peripheral surfaces of the first and second side portions 52, 53 or face each other in the left-right direction with a small gap therebetween. This restricts the slave jaw 24 from moving left-right relative to the master jaw 23. In other words, the slave jaw 24 is restricted from moving relative to the master jaw 23. This allows the slave jaw 24 to be more firmly fixed to the master jaw 23 against rotation of the chuck body 21 during machining.

[0061] Furthermore, as described above, the attachment work of the child claw 24 can be performed by aligning the ridges 54A, 55A, etc. with the positions of the recessed grooves 43, etc., and then moving the child claw 24 axially until the ball 57B of the biasing member 57 is inserted into the attachment / detachment recess 48, and then sliding the child claw 24 further radially outward until the ball 57B fits into the recess 47 (the position where the first and second flat surfaces 41A, 51E are in surface contact). This allows the user to easily attach the child claw 24 to the parent claw 23.

[0062] Furthermore, in the removal operation of the child jaw 24, the child jaw 24 is slid radially inward against the biasing force of the spring 57A to a position where the ball 57B comes out of the recess 47 and is inserted into the attachment / detachment recess 48, i.e., the position shown in FIGS. 11 to 13. This allows the child jaw 24 to be moved to a position where it can be removed from the parent jaw 23. The user can easily remove the child jaw 24 from the parent jaw 23 by inserting the ridges 54A, 55A into the recessed grooves 43, etc., and moving the child jaw 24 toward the tip in the axial direction. This allows the child jaw 24 to be easily replaced with an appropriate one depending on, for example, the type of workpiece W.

[0063] Therefore, the detachment recess 48 is formed at a position where the ball 57B is inserted when the ridges 54A, 55A are aligned with the grooves 43, etc. As a result, when the secondary claw 24 is moved radially inward from the attached state, the biasing force changes as the biasing member 57 fits into the detachment recess 48, allowing the user to sense by touch that the secondary claw 24 has been moved to the detachment position. In other words, the provision of the detachment recess 48 makes it easier for the user to recognize the detachment position where the ridges 54A, 55A are aligned with the grooves 43, etc., facilitating the removal of the secondary claw 24. As a result, the time required for replacing the secondary claw 24 can be reduced.

[0064] As described above, the axial position of the biasing member 57 is adjusted by the amount it is screwed into the threaded portion 51C, and the force with which the ball 57B presses the master claw 23 (recess 47, attachment / detachment recess 48, etc.) by the spring 57A is adjusted according to the screwing position. This makes it possible to adjust the magnitude of the force required for attachment, the fixing force after attachment, and the force required for removal by adjusting the attachment position of the biasing member 57, i.e., the screwing position.

[0065] Incidentally, the first mounting surface 27B is an example of a main body side engaging portion. The second mounting surface 22B is an example of a backing side engaged portion. The biasing member 29 is an example of a backing side biasing member. The spring 29A is an example of a backing side elastic member. The ball 29B is an example of a backing side inserting member. The first and second plates 54, 55 are an example of plates. The spring 57A is an example of an elastic member. The ball 57B is an example of an inserting member.

[0066] As described above, the present embodiment provides the following effects. In one aspect of this embodiment, the chuck device 11 includes a chuck body 21, a backing 22, a main jaw 23, and a secondary jaw 24. The chuck body 21 rotates about the axis of the spindle by a spindle 25. The backing 22 is detachably attached to the chuck body 21. The secondary jaw 24 is detachably attached to the main jaw 23 attached to the chuck body 21, and clamps the workpiece W abutting against the backing 22 from the outside in the radial direction. The main jaw 23 has a recess 47 recessed in a direction parallel to the axial direction and a locking portion 41 provided radially outside the recess 47. The biasing member 57 attached to the secondary jaw 24 includes a spring 57A and a ball 57B that is inserted into the recess 47 from a direction parallel to the axial direction by the elastic force of the spring 57A. Furthermore, each of the first and second plates 54, 55 of the child claw 24 is located on the axial opposite side of the biasing member 57 when the child claw 24 is attached to the parent claw 23, and holds the parent claw 23 between itself and the ball 57B inserted in the recess 47. When the ball 57B is inserted in the recess 47, the second flat surface 51E of the main body 51 comes into contact with and is locked to the locking portion 41 from the radially inner side.

[0067] This allows the child claw 24 to be attached to the parent claw 23 using the biasing member 57, in which the ball 57B moves forward and backward due to the spring 57A. For example, the child claw 24 can be attached to the parent claw 23 by fitting the ball 57B into the recess 47 by moving the child claw 24 relative to the parent claw 23 from the inside to the outside in the radial direction. The child claw 24 is restricted from moving in the axial direction by sandwiching the parent claw 23 from both axial sides between the first and second plates 54, 55 and the ball 57B. Furthermore, with the ball 57B inserted in the recess 47, the second flat surface 51E of the child claw 24 contacts the locking portion 41 from the inside in the radial direction. This restricts the child claw 24 from moving in the radial direction. Therefore, the child claw 24 can be firmly attached to the parent claw 23.

[0068] On the other hand, when removing the child claw 24, the child claw 24 can be removed by, for example, moving the child claw 24 radially inward relative to the parent claw 23 against the biasing force of the biasing member 57. In other words, the child claw 24 can be attached and detached from the parent claw 23 with a single touch. This reduces the burden of the work of replacing the child claw 24 attached to the parent claw 23.

[0069] It goes without saying that the present disclosure is not limited to the above-described embodiments, and various improvements and modifications are possible within the scope of the present disclosure. For example, although the above embodiment is a so-called triple-jaw chuck device 11, the present invention is not limited to this. For example, a collet chuck may be used in which the backing plate mounting portion 27 is provided with a positioning member 27C and a main body recess 27D, and the backing plate 22 is provided with a positioning hole 22C and a biasing member 29. The recesses and main body recesses of the present disclosure are not limited to countersunk holes, but may be vertically or horizontally elongated holes. The shapes and numbers of components in the above embodiment are merely examples. For example, the combination of the master claw 23 and the slave claw 24 may be one, two, or four or more sets. Two or more positioning members 27C may be provided, and one or three or more biasing members 57 may be provided for one slave claw 24. The abutment 22 may be provided with one or two or more biasing members 29. The slave claw 24 may be configured to include one of the first and second plates 54, 55 (protruding strips 54A, 55A). One protruding strip 54A, 55A may be provided. In the above embodiment, the axis of the spindle of the chuck device 11 is parallel to the installation surface of the device, but this is not limited to this. For example, the axis may be perpendicular to the installation surface. Furthermore, the machine tool equipped with the chuck device 11 is not limited to a lathe. Therefore, the machine equipped with the chuck device of the present disclosure may be, for example, a horizontal lathe, a face lathe, a vertical lathe, a single-spindle lathe, a double-spindle lathe, a milling machine, a drilling machine, etc. [Explanation of symbols]

[0070] 11 chuck device, 21 chuck body, 22 stopper, 22A insertion hole, 22B second mounting surface (stopper side engaged portion), 22C positioning hole, 23 master jaw, 24 slave jaw, 27A shaft portion, 27B first mounting surface (main body side engaged portion), 27C positioning member, 27D main body side recess, 29 biasing member (stopper side biasing member), 29A spring (stopper side elastic member), 29B ball (stopper side inserted member), 41A first flat surface, 43 groove, 47 recess, 48 ​​attachment / detachment recess, 51E second flat surface (engaged portion), 54 first plate (plate), 55 second plate (plate), 57 biasing member, 57A spring (elastic member), 57B ball (insertion member), W workpiece.

Claims

1. a chuck body that rotates around the axis of the spindle; a stopper detachably attached to the chuck body; a master jaw attached to the chuck body; a child jaw that is detachably attached to the parent jaw and that clamps the workpiece that is in contact with the abutment from the outside in a direction perpendicular to the axis; Equipped with The main claw is a recess formed in a direction parallel to the axis; a locking portion provided on the outer side of the recess in a direction perpendicular to the axis; and The baby nail is an urging member having an elastic member and an insertion member that is inserted into the recess in a direction parallel to the axis by the elastic force of the elastic member; a plate that is located on the opposite side of the main jaw in a direction parallel to the axis from the biasing member when attached to the main jaw, and that holds the main jaw between itself and the insertion member inserted into the recess; a locked portion that contacts and is locked to the locking portion from an inside in a direction perpendicular to the axis when the insertion member is inserted into the recess; and The main claw is a groove formed in a direction parallel to the axis, The plate is a protrusion formed to a size that allows it to be inserted into the recessed groove; The recessed portion is the protrusion is aligned with the position of the recessed groove and moved in a direction parallel to the axis, and the child jaw is moved outward in a direction perpendicular to the axis from a state in which the plate is positioned on the base end side of the chuck body with respect to the recessed groove, and the child jaw is formed at a position where the insertion member is inserted, The main claw is a detachable recess portion located on the inner side of the recess portion in a direction perpendicular to the axis; The attachment / detachment recess is A chuck device that is recessed in a direction parallel to the axis and is formed at a position where the insertion member is inserted when the convex ridge of the plate is aligned with the position of the concave groove in a direction perpendicular to the axis.

2. The recessed portion is a countersink recessed in a direction parallel to the axis, The baby nail is 2. The chuck device according to claim 1, wherein the insertion member is pressed by the elastic member to a position inward from the center of the countersink in a direction perpendicular to the axis, and the chuck device is attached to the master jaw in a state where the engaged portion is in contact with the engaging portion.

3. The locking portion is a first plane on the inner side in a direction perpendicular to the axis; The locked portion is a second plane on the outside in a direction perpendicular to the axis; The baby nail is The chuck device according to claim 2 , wherein the chuck device is attached to the master jaw in a state where the second flat surface of the locked portion is in surface contact with the first flat surface of the locking portion.

4. The biasing member is 4. The chuck device according to claim 1, wherein the chuck device is a ball plunger, has a ball as the insertion member, is attached by being screwed onto the child jaw, and a force with which the ball presses against the recess due to an elastic force of the elastic member is adjusted according to a position at which the ball is screwed.

5. The chuck body includes: Shaft and a main body side recess recessed inward in a direction perpendicular to the axis; a body-side engaging portion provided closer to the base end of the chuck body than the body-side recess in a direction parallel to the axis; and The said reserve is an insertion hole into which the shaft portion is inserted; an abutment side biasing member having an abutment side elastic member and an abutment side insertion member that is inserted into the main body side recess from a direction perpendicular to the axis by the elastic force of the abutment side elastic member; a stopper side engaged portion that contacts and is engaged with the main body side engaging portion from a tip side of the chuck main body in a direction parallel to the axis when the shaft portion is inserted into the insertion hole and the stopper side insertion member is inserted into the main body side recess; The chuck device according to any one of claims 1 to 4, comprising:

6. The chuck body includes: a first mounting surface provided around the shaft portion and facing a tip side of the chuck body in a direction parallel to the axis; The said reserve is a second mounting surface that contacts the first mounting surface when attached to the chuck body; The first mounting surface has: a positioning member protruding from a tip end side of the chuck body in a direction parallel to the axis; The second mounting surface has 6. The chuck device according to claim 5, further comprising a positioning hole recessed in a direction parallel to the axis, into which the positioning member is inserted when the abutment is attached to the chuck body.

7. a chuck body that rotates around the axis of the spindle; a stopper detachably attached to the chuck body; a master jaw attached to the chuck body; a child jaw that is detachably attached to the parent jaw and that clamps the workpiece that is in contact with the abutment from the outside in a direction perpendicular to the axis; A method for attaching a sub-jaw to a chuck device comprising: The main claw is a recess formed in a direction parallel to the axis; a locking portion provided on the outer side of the recess in a direction perpendicular to the axis; and The baby nail is an elastic member; and a biasing member having an insertion member to which the elastic force of the elastic member is applied; Plate and A locked portion; and The main claw is a groove formed in a direction parallel to the axis, The plate is a protrusion formed to a size that allows it to be inserted into the recessed groove; The recessed portion is the protrusion is aligned with the position of the recessed groove and moved in a direction parallel to the axis, and the child jaw is moved outward in a direction perpendicular to the axis from a state in which the plate is positioned on the base end side of the chuck body with respect to the recessed groove, and the child jaw is formed at a position where the insertion member is inserted, The main claw is a detachable recess portion located on the inner side of the recess portion in a direction perpendicular to the axis; The attachment / detachment recess is a recess formed in a direction parallel to the axis, and formed at a position where the insertion member is inserted when the protrusion of the plate is aligned with the position of the recessed groove in a direction perpendicular to the axis, How to attach the child nails: disposing the thumb nail between the plate and the biasing member in a direction parallel to the axis; a step of sliding the child claw outward in a direction perpendicular to the axis relative to the parent claw while the parent claw is disposed between the plate and the biasing member, inserting the insert member into the recess from a direction parallel to the axis by the elastic force of the elastic member, sandwiching the parent claw between the insert member inserted into the recess and the plate, and bringing the locked portion into contact with the locking portion from the inside in the direction perpendicular to the axis to lock it; How to attach the child nails, including:

Images