clamping device

Abstract

A chuck device is provided which is inexpensive and can be easily constructed. A chuck mechanism (200) constituting a chuck device (100) has a movable member (210) (piston (220), shaft member (230), action member (240), pressing member (250)) which is movable in the direction of extension of a body portion inside space (120), a disc spring (260), a ring spring (270), a spring (280), and a collet (300). A drive mechanism (400) has a movable member (430) which is movable in the direction of extension of a body portion inside space (130) in conjunction with the rotation of a rotation member (410). A closed space (121, 131) and a communication path (140) are filled with oil. When the rotation member (410) is rotated in one direction, the movable member (210) is moved to the closed space (121) side, and the chuck mechanism (200) is set to a chuck mode in which a tool holder (510) is held. When the rotation member (410) is rotated in the other direction, the movable member (210) is moved to the side opposite the closed space (121), and the chuck mechanism (200) is set to a release mode in which the tool holder (510) is released from being held.

Description

TECHNICAL FIELD

[0001] The present application relates to a clamping device that clamps a clamped member. BACKGROUND

[0002] In a machine tool that processes a workpiece using a tool, a clamping device that clamps a clamped member, which is a tool or a tool holder that holds a tool, or the like, is used. For example, the clamping device disclosed in Patent Literature 1 is used. In Patent Literature 1, a clamping device that clamps or releases a clamped member using rotation of a motor is disclosed. Specifically, the rotational force of the motor is transmitted to a clamping mechanism via a speed reduction mechanism, a motion conversion mechanism that converts rotational motion to linear motion.

[0003] Prior art documents

[0004] Patent documents

[0005] Patent Literature 1: Japanese Patent Application Publication No. 2016-144853 SUMMARY

[0006] PROBLEMS TO BE SOLVED BY THE INVENTION

[0007] The clamping device disclosed in Patent Literature 1 uses a speed reduction mechanism and a motion conversion mechanism composed of gears, and thus the structure is complicated and is expensive.

[0008] The present application has been made in view of such a problem, and has an object to provide a clamping device that is inexpensive and can be easily constituted.

[0009] MEANS FOR SOLVING THE PROBLEM

[0010] The clamped member clamped by the clamping device of the present application has a handle portion in which a recess is formed.

[0011] The present application has a main body portion, a clamping mechanism, and a drive mechanism that drives the clamping mechanism.

[0012] The main body portion has a first main body portion inside space, a second main body portion inside space, and a communication path. The main body portion can be constituted by combining a plurality of members by using a bolt or the like, or can be constituted by a single member. The extension direction of the first main body portion inside space and the extension direction of the second main body portion inside space can be appropriately set. For example, it can be set to a direction that intersects (including being orthogonal to) or the same direction (parallel).

[0013] The clamping mechanism has a first movable member, a first chamber, a first elastic member, and a collet. The first movable member is movable in the extension direction of the inside space of the first main body portion. The volume of the first chamber changes in accordance with the movement of the first movable member. The first elastic member generates an elastic force that moves the first movable member in the direction in which the volume of the first chamber decreases with respect to the main body portion. The collet has a first protrusion that can be engaged with a recess of the clamped member. As the collet, various structures of collets can be used.

[0014] The collet can be set in a clamped mode in which the first protrusion and the recess are engaged or in a released mode in which the engagement of the first protrusion and the recess is released. The collet is set in the clamped mode by the movement of the first movable member in the direction in which the volume of the first chamber decreases. In addition, the collet is set in the released mode by the movement of the first movable member in the direction in which the volume of the first chamber increases.

[0015] The drive mechanism has a second movable member and a second chamber. The second movable member is movable in the extension direction of the inside space of the second main body portion. The volume of the second chamber changes in accordance with the movement of the second movable member.

[0016] The communication path is formed to communicate the first chamber and the second chamber. The first chamber, the second chamber, and the communication path are filled with a power transmission medium. As the power transmission medium, it is preferable to use oil.

[0017] The cross-sectional area of the first chamber is set to be larger than the cross-sectional area of the second chamber. Thereby, it is possible to increase the pressing force that moves the first movable member to the side opposite to the first chamber.

[0018] In the present application, when the second movable member moves in the direction in which the volume of the second chamber increases, the first movable member moves in the direction in which the volume of the first chamber decreases due to the elastic force of the first elastic member, and thereby the collet is set in the clamped mode.

[0019] In addition, when the second movable member moves in the direction in which the volume of the second chamber decreases, the first movable member moves in the direction in which the volume of the first chamber increases against the elastic force of the first elastic member. Thereby, the collet is set in the released mode.

[0020] As the structure that sets the collet in the clamped mode or the released mode in conjunction with the movement of the first movable member, various structures can be used.

[0021] In the present application, it is possible to obtain a clamping device that is inexpensive and can be easily configured.

[0022] In a different aspect of the present application, the drive mechanism has a rotating member. In addition, the second movable member is configured to be movable in the extension direction of the inside space of the second main body portion in conjunction with the rotation of the rotating member. As the way to move the second movable member in conjunction with the rotation of the rotating member, various ways can be used.

[0023] Also, the second movable member is configured to move in a direction in which the volume of the second chamber increases when the rotating member is rotated in one direction, and to move in a direction in which the volume of the second chamber decreases when the rotating member is rotated in the other direction.

[0024] In the present aspect, for example, in the case where the rotating member is driven by a motor, a small motor can be used to obtain the pressing force that moves the first movable member in the direction in which the volume of the first chamber increases.

[0025] In the present aspect, the driving mechanism can be configured simply.

[0026] In a different aspect of the present application, the handle portion of the clamping member has a handle inner circumferential surface that forms a handle inner space that is open at one end. Also, a recess is formed in the handle inner circumferential surface.

[0027] The first movable member has a first piston and a first shaft member. The first piston forms the first chamber. The first shaft member is provided on the side opposite the first chamber with respect to the first piston (the side in which the volume of the first chamber increases), and extends in the extension direction of the first body portion inner space. The first movable member can be configured, for example, by combining a first piston and a first shaft member that are formed separately, or can be configured by a single member that has a first piston and a first shaft member.

[0028] In addition, the collet has a plurality of collet members that are arranged in a circumferential direction on the outer circumferential side of the first shaft member.

[0029] Each collet member extends in the circumferential direction and the axial direction. Each collet member has a collet member inner circumferential surface and a collet member outer circumferential surface. In addition, a first protrusion protrudes outward from the end portion of each collet member on the side opposite the first chamber.

[0030] The inner circumferential surface of the collet member has a first collet member inner circumferential surface portion and a second collet member inner circumferential surface portion disposed on the side opposite the first chamber with respect to the first collet member inner circumferential surface portion. When viewed in a cross section along the extension direction of the first shaft member, the second collet member inner circumferential surface portion extends at an inclination angle θ with respect to the extension direction of the first collet member inner circumferential surface portion. The inclination angle θ is set such that the interval between the extension line of the first collet member inner circumferential surface portion and the second collet member inner circumferential surface portion increases from the side of the first chamber toward the side opposite the first chamber. The inclination angle θ is set, for example, such that in a state (including a state of abutment) in which the first collet member inner circumferential surface portion is close to the outer circumferential surface of the first shaft member, the first protrusion is able to engage with the recess of the clamped member, and in a state (including a state of abutment) in which the second collet member inner circumferential surface portion is close to the outer circumferential surface of the first shaft member, the engagement of the first protrusion and the recess of the clamped member is released.

[0031] In the present aspect, the first collet member inner circumferential surface portion of each collet member is made to approach the first shaft member when the first piston moves in the direction in which the volume of the first chamber decreases (the side of the first chamber). That is, the second collet member inner circumferential surface portion and the first protrusion are made to move away from the first shaft member. Thus, the collet is set to the clamped mode.

[0032] Further, the second collet member inner circumferential surface portion of each collet member is made to approach the first shaft member when the first piston moves in the direction in which the volume of the first chamber increases (the side opposite the first chamber). That is, the first protrusion is made to approach the first shaft member, and the first collet member inner circumferential surface portion is made to move away from the first shaft member. Thus, the collet is set to the released mode.

[0033] In the present aspect, it is possible to easily set the collet (the plurality of collet members that constitute the collet) to the clamped mode or the released mode.

[0034] In a different aspect of the present application, the clamping mechanism has a second elastic member. The second elastic member generates an elastic force that causes the first collet member inner circumferential surface portion of each collet member to approach the first shaft member.

[0035] In the present aspect, the first collet member inner circumferential surface portion of each collet member approaches the first shaft member due to the elastic force of the second elastic member when the first piston moves in the direction in which the volume of the first chamber decreases. Thus, the collet is set to the clamped mode.

[0036] Further, the second collet member inner circumferential surface portion of each collet member approaches the first shaft member against the elastic force of the second elastic member when the first piston moves in the direction in which the volume of the first chamber increases. Thus, the collet is set to the released mode.

[0037] In the present aspect, it is possible to easily set the collet to the clamped mode or the released mode.

[0038] In a different aspect of the present application, each collet member has a second protruding portion protruding toward the outer peripheral side at the end portion on the first chamber side. In addition, the first shaft member has an abutting portion capable of abutting against the second protruding portion of each collet member.

[0039] In the present aspect, when the first piston moves in the direction in which the volume of the first chamber decreases, the abutment of the abutting portion of the first movable member and the second protruding portion of each collet member is released. Also, at this time, the first collet member inner peripheral surface portion of each collet member approaches the first shaft member due to the elastic force of the second elastic member. Thus, the collet is set to the clamped mode.

[0040] In addition, when the first piston moves in the direction in which the volume of the first chamber increases, the abutting portion of the first movable member abuts against the second protruding portion of each collet member, and a force that moves the second protruding portion toward the outer peripheral side acts. Also, at this time, the second collet member inner peripheral surface portion of each collet member approaches the first shaft member against the elastic force of the second elastic member. Thus, the collet is set to the released mode.

[0041] In the present aspect, it is possible to easily set the collet to the clamped mode or the released mode.

[0042] In a different aspect of the present application, the first shaft member has a protruding portion protruding toward the outer peripheral side at the end portion on the side opposite to the first chamber.

[0043] In the present aspect, when the first piston moves in the direction in which the volume of the first chamber decreases, the protruding portion of the first shaft member abuts against a part of the second collet member inner peripheral surface portion of each collet member, and a force that moves the second collet member inner peripheral surface portion away from the first shaft member acts. Thus, the collet is set to the clamped mode.

[0044] In addition, when the first piston moves in the direction in which the volume of the first chamber increases, the abutment of the protruding portion of the first shaft member and the part of the second collet member inner peripheral surface portion of each collet member is released. Also, at this time, the second collet member inner peripheral surface portion of each collet member approaches the first shaft member. Thus, the collet is set to the released mode.

[0045] In the present aspect, it is possible to improve the clamping force, and to securely hold the engagement of the first protruding portion and the recess of the clamped member.

[0046] In a different aspect of the present application, the main body portion has a movement restriction portion at a predetermined position, the movement restriction portion restricting movement of each collet member in the direction in which the volume of the first chamber increases along the extension direction of the first main body portion inner side space.

[0047] In addition, the clamping mechanism has a third elastic member. The third elastic member is configured to generate an elastic force that separates the first movable member and each cartridge clamp member.

[0048] Each cartridge clamp member is disposed at a predetermined position by the movement restriction portion irrespective of the movement of the first movable member due to the elastic force of the third elastic member.

[0049] In the present aspect, it is possible to easily set the cartridge clamp to the clamping mode or the releasing mode.

[0050] In a different aspect of the present application, the second movable member has a second piston and a second shaft member. The second piston forms a second chamber. The second shaft member is provided on a side opposite to the second chamber with respect to the second piston and extends in the extension direction of the second body portion inner space. The second shaft member is configured to be movable in the extension direction of the second body portion inner space in conjunction with the rotation of the rotation member.

[0051] The second movable member can be configured, for example, by combining the second piston and the second shaft member formed separately by using a bolt or the like, or can be configured by a single member having the second piston and the second shaft member.

[0052] In the present aspect, it is possible to convert the rotation of the rotation member to the movement in the extension direction of the second body portion inner space with a simple structure.

[0053] Effects of the Invention

[0054] In the present application, it is possible to obtain a clamping device that is inexpensive and can be easily configured. BRIEF DESCRIPTION OF DRAWINGS

[0055] Figure 1 is a cross-sectional view of the clamping device of the first embodiment.

[0056] Figure 2 is a cross-sectional view of the clamping mechanism that configures the clamping device of the first embodiment.

[0057] Figure 3 is a cross-sectional view of the drive mechanism that configures the clamping device of the first embodiment.

[0058] Figure 4 is a side view of one embodiment of the cartridge clamp used in the clamping mechanism that configures the clamping device of the first embodiment.

[0059] Figure 5 is a view obtained by viewing Figure 4 from the direction of the arrow V.

[0060] Figure 6 is a VI-VI line view of Figure 5 .

[0061] Figure 7 is a sectional view of an example of a clamped member clamped by the clamping device of the first embodiment.

[0062] Figure 8 is a view showing the state of the collet in the state shown in Figure 1

[0063] Figure 9 is a view showing the state of the collet in the state shown in

[0064] Figure 10 is a view showing the state of the collet in the state shown in Figure 9

[0065] Figure 11 is a view showing the state of the collet in the state shown in

[0066] Figure 12 is a view showing the state of the collet in the state shown in

[0067] Figure 13 is a view showing the state of the collet in the state shown in Figure 12

[0068] Figure 14 is a sectional view of the clamping device of the second embodiment.

[0069] Figure 15 is a side view of a different embodiment of the collet.

[0070] Figure 16 is a view showing the state of the collet of the different embodiment in the state set to the release mode. DETAILED DESCRIPTION

[0071] The following detailed description is directed to a preferred application of the application for the purpose of conveying a detailed understanding of the application to those skilled in the art. The scope of the application is not limited to the detailed description, but is determined by the claims. Therefore, the combination of structures, methods in the following detailed description is not all necessarily essential to the practice of the application, and is merely used to disclose a representative way of the application in the detailed description together with the accompanying drawings.

[0072] ​​​An embodiment of the present application will be described below with reference to the drawings.

[0073] Referring to Figures 1-3 A first embodiment of the clamping device of the present application will be described. Furthermore, Figure 1 is a cross-sectional view of the clamping device 100 of the first embodiment, Figure 2 is a cross-sectional view of the clamping mechanism 200, Figure 3 is a cross-sectional view of the drive mechanism 400.

[0074] The clamping device 100 of the present embodiment is configured as a tool holder clamping device that clamps a tool holder.

[0075] Referring to Figure 7 An example of a tool holder clamped by the clamping device 100 of the present embodiment will be described.

[0076] Furthermore, hereinafter, with respect to the tool holder 510, the side (upper side in Figure 7 ) that is inserted into the shank insertion space 122 (to be described later) of the clamping device 100 along the center line T of the tool holder 510 will be referred to as the "rear end side", and the side (lower side in Figure 7 ) opposite to the side that is inserted into the shank insertion space 122 will be referred to as the "front end side".

[0077] Figure 7 The tool holder 510 illustrated in the drawing holds a tool 550.

[0078] The tool holder 510 has a tool holder rear end surface 510B, a tool holder inner peripheral surface 511, and a tool holder outer peripheral surface 512.

[0079] The tool holder inner peripheral surface 511 has tool holder inner peripheral surface portions 511a to 511f. The tool holder inner side space 510a that is open at one end side (the rear end side) is formed by the tool holder inner peripheral surface 511. In addition, the tool holder outer peripheral surface 512 has tool holder outer peripheral surface portions 512a to 512c.

[0080] A shank 520 is provided on the rear end side of the tool holder 510, and the shank 520 is inserted into the shank insertion space 122 of the clamping device 100. The shank 520 is formed by the rear end face 510B of the tool holder, an inner circumferential surface of the shank including the inner circumferential surface portions 511b to 511f of the tool holder, and an outer circumferential surface of the shank including the outer circumferential surface portion 512c of the tool holder. The inner and outer circumferential surfaces of the shank have circular cross-sections. An inner shank space 520a with an end-side (rear end side) opening is formed by the inner circumferential surface of the shank. Furthermore, a recess 523 is formed by utilizing the inner circumferential surface portion (inner circumferential surface portion of the tool holder) 511e that forms the inner circumferential surface of the shank, which can engage with the protrusions 313A (described later) of each collet member 310 constituting the collet 300. Preferably, the recess 523 is formed as a groove extending in the circumferential direction.

[0081] The clamping device 100 of this embodiment includes a main body 110, a clamping mechanism 200, and a driving mechanism 400.

[0082] The main body 110 has inner spaces 120 and 130 that are open at one end. In this embodiment, the inner spaces 120 and 130 are formed such that the extending direction of the inner space 120 (center line H1) and the extending direction of the inner space 130 (center line H2) are orthogonal. Of course, the extending directions of the inner spaces 120 and 130 can be appropriately selected.

[0083] In addition, the main body 110 has a connecting passage 140 that connects the sealed space 121 (described later) formed on the side opposite to the opening in the inner space 120 of the main body and the sealed space 131 (described later) formed on the side opposite to the opening in the inner space 130 of the main body.

[0084] The inner space 120 of the main body corresponds to the "first inner space of the main body" of the present invention, and the inner space 130 of the main body corresponds to the "second inner space of the main body" of the present invention. In addition, the sealed space 121 corresponds to the "first chamber" of the present invention, the sealed space 131 corresponds to the "second chamber" of the present invention, and the connecting path 140 corresponds to the "connecting path" of the present invention.

[0085] like Figure 2 As shown, the inner peripheral surface of the main body forming the inner space 120 of the main body has inner peripheral surface portions 120a to 120l.

[0086] A protrusion is formed on the inner circumferential surface portion 120b to 120d of the main body portion, protruding toward the centerline H1 (radially inward). Each collet member 310 (described later) constituting the collet 300 is arranged across this protrusion on the outer circumferential side of the shaft member 230 (described later) along the extension direction of the centerline H1. When each collet member 310 abuts against the inner circumferential surface portion 120d of the main body portion forming the protrusion, the axial movement of each collet member 310 toward the side opposite to the sealed space 121 is restricted.

[0087] The inner peripheral surface portion 120d of the main body corresponds to the "movement restriction portion provided at a predetermined position in the main body and restricting the movement of the collets (each collet member) along the extension direction of the inner space of the first main body to the side opposite to the first chamber" of the present invention.

[0088] The inner circumferential surface portion 120h of the main body extends in a direction intersecting the extension direction of the center line H1, forming a stepped surface that connects the inner circumferential surface portions 120g and 120i of the main body.

[0089] The inner peripheral surface portion 120j of the main body extends in a direction intersecting the extension direction of the center line H1, forming a stepped surface that connects the inner peripheral surface portions 120i and 120k of the main body. The inner peripheral surface portion 120j of the main body functions as a movement restriction part to limit the movement of the movable member 210 along the center line H1 to the side opposite to the enclosed space 121.

[0090] The inner circumferential surface portion 120l of the main body forms the bottom surface of the inner space 120 of the main body.

[0091] A shank insertion space 122 is formed on the opening side of the inner peripheral surface portions 120a and 120b of the main body portion, for inserting the shank portion 520 of the tool holder 510.

[0092] like Figure 3 As shown, the inner peripheral surface of the main body forming the inner space 130 of the main body has inner peripheral surface portions 130a to 130i.

[0093] The inner peripheral surface portion 130f of the main body extends in a direction intersecting the extension direction of the center line H2, forming a stepped surface that connects the inner peripheral surface portions 130e and 130g of the main body. The inner peripheral surface portion 130g of the main body functions as a movement restriction part that limits the movement of the movable member 430 (described later) along the center line H2 toward the enclosed space 131.

[0094] The inner circumferential surface portion 130a of the main body forms the bottom surface of the inner space 130 of the main body.

[0095] The clamping mechanism 200 is disposed in the inside space 120 of the main body portion. In the present embodiment, the clamping mechanism 200 is disposed such that the center line P of the clamping mechanism 200 coincides (including "substantially coincides") with the center line H1 of the inside space 120 of the main body portion.

[0096] Further, hereinafter, with respect to the clamping mechanism 200, the side of the opening portion (the lower side in Figure 1 and Figure 2 ) will be referred to as the "front end side", and the side opposite to the opening portion (the upper side in Figure 1 and Figure 2 ) will be referred to as the "rear end side".

[0097] The clamping mechanism 200 has a movable member 210, a disc spring 260, a ring spring 270, a spring 280, and a collet 300.

[0098] The movable member 210 is movable along the extension direction of the inside space 120 of the main body portion (hereinafter, referred to as the "extension direction of the center line H1"). The movable member 210 has a piston 220, a shaft member 230, an operation member 240, and a pressing member 250. In the present embodiment, the movable member 210 is configured by combining the piston 220, the shaft member 230, the operation member 240, and the pressing member 250 which are formed separately by using a bolt or the like. Of course, the movable member 210 can also be configured by one member.

[0099] The movable member 210 corresponds to the "first movable member" of the present application.

[0100] The piston 220 has a piston front end face 220A, a piston rear end face 220B, and a piston outer peripheral face 222. The piston outer peripheral face 222 has a circular cross-sectional shape.

[0101] An O-ring 223 is disposed between the piston outer peripheral face 222 and the inner peripheral face portion 120k of the main body portion. Thus, a closed space 121 is formed by the inner peripheral face portion 120k, 120l of the main body portion and the piston 220 (the piston rear end face 220B). That is, the piston 220 forms the closed space 121.

[0102] The piston 220 corresponds to the "first piston of the first movable member" of the present application.

[0103] The shaft member 230 extends along the extension direction of the center line H1 on the front end side (the side opposite to the closed space 121) of the piston 220. In the present embodiment, the shaft member 230 has a circular cross-sectional shape.

[0104] The shaft member 230 has a shaft member front end surface 230A, a shaft member rear end surface 230B, and a shaft member outer peripheral surface 232.

[0105] The shaft member outer peripheral surface 232 has shaft member outer peripheral surface portions 232a to 232d. A protruding portion 233 protruding outward in the peripheral direction is formed by the shaft member front end surface 230A and the shaft member outer peripheral surface portions 232a to 232c on the front end side of the shaft member 230. In the present embodiment, the shaft member outer peripheral surface portion 232b is formed as a tapered surface inclined such that the distance from the center line H1 becomes longer from the rear end side toward the front end side.

[0106] The shaft member 230 corresponds to the "first shaft member of the first movable member" of the present application, and the protruding portion 233 corresponds to the "protruding portion of the first shaft member" of the present application.

[0107] The action member 240 is provided on the outer peripheral side of the shaft member 230 on the front end side of the piston 220 and extends along the center line H1.

[0108] The action member 240 is formed in a cylindrical shape and has an action member front end surface 240A, an action member rear end surface 240B, an action member inner peripheral surface 241, and an action member outer peripheral surface 242. The action member inner peripheral surface 241 and the action member outer peripheral surface 242 have a circular cross-sectional shape.

[0109] The action member front end surface 240A has action member front end surface portions 240A1 to 240A3. The action member front end surface portion 240A2 is formed as a tapered surface inclined such that the distance from the center line H1(P) becomes longer from the front end side toward the rear end side. The action member front end surface portion 240A2 is capable of abutting against a protruding portion 313B (to be described later) of a collet member 310 constituting a collet 300 (in detail, an inner peripheral surface portion 311e of the collet member).

[0110] The action member inner peripheral surface 241 has action member inner peripheral surface portions 241a to 241e. A space into which one end portion of a spring 280 (to be described later) is capable of being inserted is formed by the action member inner peripheral surface portions 241c and 241d.

[0111] The action member outer peripheral surface 242 has action member outer peripheral surface portions 242a to 242e.

[0112] The action member outer peripheral surface portion 242b extends in a direction intersecting the direction of extension of the center line H1 and is formed as a step surface connecting the action member outer peripheral surface portions 242a and 242c.

[0113] The action member outer peripheral surface portion 242d extends in a direction intersecting the direction of extension of the center line H1 and is formed as a step surface connecting the action member outer peripheral surface portions 242c and 242e.

[0114] The actuating member 240 corresponds to the "acting member of the first movable member" of the present invention, and the front end face portion 240A2 of the actuating member corresponds to the "abutting portion of the first movable member that can abut against the second protrusion of each collet member" of the present invention.

[0115] The pressing member 250 is located on the front end side of the piston 220 and on the outer periphery of the actuating member 240.

[0116] The pressing member 250 is formed in a cylindrical shape and has a front end face 250A, a rear end face 250B, an inner circumferential surface 251, and an outer circumferential surface 252.

[0117] The outer peripheral surface 252 of the pressing member has pressing member outer peripheral surface portions 252a to 252c. The pressing member outer peripheral surface portion 252b extends in a direction intersecting the extension direction of the center line H1, forming a stepped surface that connects the pressing member outer peripheral surface portions 252a and 252c.

[0118] The outer peripheral surface portion 252b of the pressing member abuts against the inner peripheral surface portion 120j of the main body, thereby restricting the movement of the movable member 210 towards the front end along the center line H1. That is, the outer peripheral surface portion 252b of the pressing member and the inner peripheral surface portion 120j of the main body constitute a movement restriction mechanism that restricts the movement of the movable member 210 towards the front end along the center line H1.

[0119] The pressing member 250 corresponds to the "pressing member of the first movable member" of the present invention.

[0120] The disc spring 260 is disposed in a compressed state between the inner peripheral surface portion 120h of the main body and the front end face 250A of the pressing member. That is, the disc spring 260 generates an elastic force that causes the movable member 210 to move relative to the main body 110 along the center line H1 toward the rear end.

[0121] The disc spring 260 corresponds to the "first elastic member that generates an elastic force that moves the first movable member relative to the main body toward the first chamber" of the present invention.

[0122] Next, refer to Figures 4-6 One embodiment of the collet 300 will be described. Furthermore, Figure 4 This is a side view of collet 300. Figure 5 Viewed from the direction of arrow V Figure 4 The resulting image, Figure 6 yes Figure 5 VI-VI line view.

[0123] The collet 300 has multiple collet components 310.

[0124] The collet member 310 is arranged along the circumferential direction at the outer peripheral side of the shaft member 230, compared to the operation member 240 at the front end side.

[0125] The collet member 310 extends along the circumferential direction and the center line P(H1) at the outer peripheral side of the shaft member 230, and has a collet member front end surface 310A, a collet member rear end surface 310B, a collet member inner peripheral surface 311 formed at the inner peripheral side, a collet member outer peripheral surface 312 formed at the outer peripheral side, and a collet member side surface 315 formed at one side and the other side along the circumferential direction. Further, as shown in Figure 5 viewed from a direction at right angles to the center line P, the collet member 310 extends in a circular arc shape along the shaft member outer peripheral surface 232.

[0126] The collet member inner peripheral surface 311 has collet member inner peripheral surface portions 311a to 311e. The collet member inner peripheral surface portion 311e is formed as a tapered surface inclined such that the distance from the center line P becomes larger from the front end side toward the rear end side.

[0127] When viewed in a cross section along the center line P(H1) (refer to Figure 6 ), the collet member inner peripheral surface portion 311a extends at an inclination angle θ with respect to the extension direction of the collet member inner peripheral surface portion 311b. The inclination angle θ is set such that the distance between the extension line of the collet member inner peripheral surface portion 311b and the collet member inner peripheral surface portion 311a becomes larger from the rear end side toward the front end side.

[0128] The collet member inner peripheral surface portion 311c abuts against the other-side end portion of the spring 280.

[0129] The collet member outer peripheral surface 312 has collet member outer peripheral surface portions 312a to 312h. The collet member outer peripheral surface portion 312g is formed as a tapered surface inclined such that the distance from the center line P(H1) becomes smaller from the rear end side toward the front end side.

[0130] A protrusion 313A protruding to the outer peripheral side is formed at the front end side of the collet member 310 by the collet member front end surface 310A and the collet member outer peripheral surface portion 312a. The protrusion 313A is formed so as to be engageable in the recess 523 of the tool holder 510.

[0131] In addition, a protrusion 313B protruding to the outer peripheral side is formed at the rear end side of the collet member 310 by the collet member rear end surface 310B, the collet member outer peripheral surface portions 312g, 312h, and the collet member inner peripheral surface portions 311b to 311e. The protrusion 313B is configured to be abuttable against the abutment portion of the operation member 240. Specifically, the collet member inner peripheral surface portion 311e forming the protrusion 313B is configured to be abuttable against the operation member front end surface portion 240A2 of the operation member 240.

[0132] The angle θ of the extension direction of the inner peripheral surface portion 311b of the collet member relative to the extension direction of the inner peripheral surface portion 311a of the collet member is set such that, when the inner peripheral surface portion 311b of the collet member is close to the outer peripheral surface 232 (outer peripheral surface portion 232d) of the shaft member 230 (including the abutting state), the protrusion 313A can engage with the recess 523 of the tool holder 510 inserted into the shank insertion space 122. Conversely, the angle θ is set such that, when the inner peripheral surface portion 311a of the collet member is close to the outer peripheral surface 232 (outer peripheral surface portion 232d) of the shaft member 230 (including the abutting state), the protrusion 313A cannot engage with the recess 523 of the tool holder 510 inserted into the shank insertion space 122 (the engagement between the protrusion 313A and the recess 523 is released).

[0133] The inner peripheral surface portion 311b of the collet member corresponds to the "inner peripheral surface portion of the first collet member" of the present invention, the inner peripheral surface portion 311a of the collet member corresponds to the "inner peripheral surface portion of the second collet member" of the present invention, the protrusion 313A corresponds to the "first protrusion of the collet member that protrudes from the end on the front end side (the side opposite to the first chamber) to the outer peripheral side" of the present invention, and the protrusion 313B corresponds to the "second protrusion of the collet member that protrudes from the end on the rear end side (the side of the first chamber) to the outer peripheral side" of the present invention.

[0134] In addition, such as Figures 4-6 As shown, with the inner circumferential surface portion 311b of each collet member 310 abutting against the outer circumferential surface portion 232d of the shaft member (the extending direction of the inner circumferential surface portion 311b of the collet member is parallel to the extending direction of the shaft member 230), a gap 316 extending along the centerline P is formed between two circumferentially adjacent collet members 310. The gap 316 includes a gap 316B and a gap 316A formed on the front end side and having a wider spacing than the gap 316B. Specifically, as... Figure 4 As shown, each collet member 310 has collet member side surface 315 with collet member side surface portion 315a to 315c. Collet member side surface portions 315a and 315c extend along the center line P. Collet member side surface portion 315b is formed as a stepped surface that connects collet member side surface portions 315a and 315c in a stepped manner.

[0135] In this embodiment, gap 316B extends along centerline P at interval N. Additionally, gap 316A extends along centerline P at an interval M (M > N) that is wider than the interval N of gap 316B.

[0136] The gap 316B corresponds to the "first gap between chuck members formed on the rear end side" of the present application, and the gap 316A corresponds to the "second gap between chuck members formed on the front end side" of the present application.

[0137] In the present embodiment, as described later, the chuck 300 is set to a clamping mode in which the chuck member inner peripheral surface portion 311b is close to the shaft member outer peripheral surface portion 232d, and the chuck member inner peripheral surface portion 311a is away from the shaft member outer peripheral surface portion 232d. In addition, the chuck 300 is set to a releasing mode in which the chuck member inner peripheral surface portion 311b is away from the shaft member outer peripheral surface portion 232d, and the chuck member inner peripheral surface portion 311a is close to the shaft member outer peripheral surface portion 232d. Here, it is necessary to be configured such that, when the chuck 300 is shifted from the clamping mode to the releasing mode, the circumferentially adjacent chuck members 310 do not contact each other. For example, the circumferentially adjacent chuck members 310 are arranged at a wide interval.

[0138] On the other hand, if the circumferentially adjacent chuck members 310 are arranged at a wide gap, there is a concern that the interval between the circumferentially adjacent chuck members 310 is deviated in a state in which the chuck member inner peripheral surface portion 311b is close to the shaft member outer peripheral surface portion 232d (clamping mode). If the interval between the chuck members 310 is deviated, there is a concern that the clamping force of each chuck member 310 to the tool holder 510 is deviated, and the holding characteristics of the tool holder 510 are reduced.

[0139] In the present embodiment, gaps having different intervals are formed between the two circumferentially adjacent chuck members 310. In addition, the interval M of the gap 316A formed on the front end side is made wider than the interval N of the gap 316B formed on the rear end side.

[0140] By making the interval M of the gap 316A on the front end side wide, it is possible to prevent the circumferentially adjacent chuck members 310 from contacting each other when set to the releasing mode. In addition, by making the interval N of the gap 316B on the rear end side narrow, it is possible to prevent the interval between the chuck members 310 from being deviated when set to the clamping mode. Thus, it is possible to make the clamping force of each chuck member 310 to the tool holder 510 substantially equal, and it is possible to stably hold the tool holder 510.

[0141] The annular spring 270 generates an elastic force that moves each chuck member 310 arranged in a circumferential direction to the radially inner side. In the present embodiment, an annular spring having a letter C shape is used as the annular spring 270. An O-ring can also be used as the annular spring 270.

[0142] In the present embodiment, as described later, the chuck 300 is set to a clamping mode in which the chuck member inner peripheral surface portion 311b is close to the shaft member outer peripheral surface portion 232d, and the chuck member inner peripheral surface portion 311a is away from the shaft member outer peripheral surface portion 232d. In addition, the chuck 300 is set to a releasing mode in which the chuck member inner peripheral surface portion 311b is away from the shaft member outer peripheral surface portion 232d, and the chuck member inner peripheral surface portion 311a is close to the shaft member outer peripheral surface portion 232d. Here, it is necessary to be configured such that, when the chuck 300 is shifted from the clamping mode to the releasing mode, the circumferentially adjacent chuck members 310 do not contact each other. For example, the circumferentially adjacent chuck members 310 are arranged at a wide interval. Figure 6As shown, grooves 312A are formed in the outer peripheral surface portions 312d to 312f of the collet members. The grooves 312A are formed in portions of the outer peripheral surface 312 of the collet members that correspond to the inner peripheral surface portion 311b of the collet members on the front end side relative to the protrusions 313B and extend in the circumferential direction.

[0143] The annular spring 270 is inserted into the grooves 312A of the respective collet members 310 arranged in the circumferential direction in an elongated state. As a result, the elastic force of the annular spring 270 acts as a force that brings the inner peripheral surface portion 311b of the collet member 310 closer to the outer peripheral surface portion 232d of the shaft member.

[0144] The annular spring 270 corresponds to the "second elastic member" of the present application.

[0145] The spring 280 is arranged between the respective collet members 310 and the operation member 240 (movable member 210) in a compressed state. The elastic force of the spring 280 acts as a force that separates the respective collet members 310 and the operation member 240 (movable member 210). The respective collet members 310 are restricted from moving toward the front end side (the side opposite the sealed space 121) relative to the main body 110 along the center line H1 by the inner peripheral surface portion 120d of the main body 110. Therefore, the elastic force of the spring 280 acts as a force that moves the respective collet members 310 toward the rear end side relative to the operation member 240 (movable member 210). That is, the respective collet members 310 are maintained in a state of abutting against the inner peripheral surface portion 120d of the main body 110 regardless of the movement of the movable member 210.

[0146] The spring 280 corresponds to the "third elastic member" of the present application.

[0147] The drive mechanism 400 is arranged in the main body inner side space 130. In the present embodiment, the drive mechanism 400 is arranged such that the center line Q of the drive mechanism 400 coincides (including "approximately coincides") with the center line H2 of the main body inner side space 130.

[0148] Further, hereinafter, with respect to the drive mechanism 400, the direction of extension of the main body inner side space 130 (center line H2) and the direction of extension of the drive mechanism 400 (center line Q), the side of the opening portion (the right side in Figure 1 and Figure 3 the left side in Figure 1 and Figure 3 ) is referred to as the "rear end side", and the side opposite the opening portion (the left side in

[0149] As shown in Figure 3 , the drive mechanism 400 includes a rotation member 410 and a movable member 430 arranged on the front end side (the sealed space 131 side) relative to the rotation member 410.

[0150] The rotating member 410 is disposed in the main body portion inside space portion formed by the main body portion inside peripheral surface portions 130f to 130i. The rotating member 410 is formed in a cylindrical shape, and has a rotating member front end surface 410A, a rotating member inside peripheral surface 411 that forms a rotating member inside space 410a of which the front end side opening is formed, and a rotating member outside peripheral surface 412. The rotating member inside peripheral surface 411 and the rotating member outside peripheral surface 412 have a circular cross section.

[0151] The rotating member inside peripheral surface 411 has rotating member inside peripheral surface portions 411a to 411d. The rotating member inside peripheral surface portion 411b extends in a direction that intersects the extending direction of the center line H2, and is formed as a step surface that connects the rotating member inside peripheral surface portions 411a and 411c. The rotating member inside peripheral surface portion 411d forms the bottom surface of the rotating member inside space 410a. An internal thread is formed in the rotating member inside peripheral surface portion 411c.

[0152] Between the rotating member outside peripheral surface 412 and the main body portion inside peripheral surface portion 130g, a bearing member 420 is disposed. Due to this, the rotating member 410 is able to rotate with respect to the main body portion 110 with the center line H2 as the center.

[0153] In the present embodiment, the rotating member is driven by a motor.

[0154] The movable member 430 has a shaft member 440 and a piston 450 that is disposed on the front end side (the sealed space 131 side) with respect to the shaft member 440. In the present embodiment, the movable member 430 is constituted by joining the shaft member 440 and the piston 450 that are formed separately by means of a bolt or the like. Of course, the movable member 430 can also be constituted by one member.

[0155] The movable member 430 corresponds to the "second movable member" of the present application.

[0156] The shaft member 440 has a shaft member front end surface 440A, a shaft member rear end surface 440B, and a shaft member outside peripheral surface 442. The shaft member outside peripheral surface 442 has a circular cross section.

[0157] The shaft member outside peripheral surface 442 has shaft member outside peripheral surface portions 442a to 442f.

[0158] An external thread that is able to threadably engage with the internal thread formed in the rotating member inside peripheral surface portion 411c is formed in the shaft member outside peripheral surface portion 442f. In addition, the shaft member 440 is restricted from rotating by a rotation restricting member 460. Due to this, when the rotating member 410 rotates, the shaft member 440 moves along the center line H2. That is, the shaft member 440 functions as a movement conversion portion that converts the rotational movement of the rotating member 410 into linear movement along the center line H2.

[0159] The shaft member 440 corresponds to "a second shaft member of a second movable member" of the present application.

[0160] The piston 450 has a piston front end surface 450A, a piston rear end surface 450B, and a piston outer peripheral surface 452. The piston outer peripheral surface 452 has a circular cross-sectional shape.

[0161] An O-ring 453 is arranged between the piston outer peripheral surface 452 and the body portion inner peripheral surface portion 130b. Thus, a closed space 131 is formed by the body portion inner peripheral surface portions 130a, 130b and the piston 450 (the piston front end surface 450A). That is, the piston 450 forms the closed space 131.

[0162] Further, the closed spaces 121, 131 and the communication path 140 are filled with a power transmission medium. In the present embodiment, oil is used as the power transmission medium.

[0163] The piston 450 corresponds to "a second piston of a second movable member" of the present application.

[0164] Reference Signs List Figures 8-13 The operation of the clamping device 100 of the first embodiment will be described.

[0165] Figure 1 、 Figure 8 A state in which the collet 300 is set to the clamping mode when the shank portion 520 of the tool holder 510 is not inserted into the shank portion insertion space 122 is shown.

[0166] In a case where the collet 300 is to be set to the clamping mode, the rotation member 410 of the drive mechanism 400 is caused to rotate in one direction, for example, the counterclockwise direction. When the rotation member 410 rotates in one direction, the movable member 430 (the shaft member 440, the piston 450) moves along the center line H2 to the side opposite to the closed space 131 (the direction in which the volume of the closed space 131 increases). Thus, the movable member 210 (the piston 220, the shaft member 230, the action member 240, the pressing member 250) of the clamping mechanism 200 moves along the center line H1 to the closed space 121 side (the direction in which the volume of the closed space 121 decreases) due to the elastic force of the disc spring 260.

[0167] At this time, each collet member 310 constituting the collet 300 is held in a state of abutting against the inner peripheral surface portion 120d of the main body portion due to the elastic force of the spring 280. Also, since the movable member 210 moves to the side of the sealed space 121, the abutment of the operating member 240 and the protruding portion 313B of each collet member 310 (specifically, the abutment of the operating member front end surface portion 240A2 and the collet member inner peripheral surface portion 311e) is released. Due to this, the collet member inner peripheral surface portion 311b of each collet member 310 is brought close to the shaft member outer peripheral surface 232 (the shaft member outer peripheral surface portion 232d) of the shaft member 230 due to the elastic force of the annular spring 270, and the collet member inner peripheral surface portion 311a and the protruding portion 313A move to the outer peripheral side (in a direction away from the shaft member 230).

[0168] Also, since the movable member 210 moves to the side of the sealed space 121, the protruding portion 233 of the shaft member 230 (specifically, the shaft member outer peripheral surface portion 232b that forms the protruding portion 233) abuts against a portion of the collet member inner peripheral surface portion 311a of each collet member 310. Due to the abutment of the protruding portion 233 of the shaft member 230 against the collet member inner peripheral surface portion 311a of each collet member 310, a force that acts to move the protruding portion 233 to the outer peripheral side is generated. This force is added to the clamping force generated by the elastic force of the annular spring 270. Due to this, it is possible to increase the clamping force.

[0169] Next, the operation of inserting the handle portion 520 of the tool holder 510 into the handle portion insertion space 122 will be described with reference to FIG. 6. Figures 9-11 The operation of inserting the handle portion 520 of the tool holder 510 into the handle portion insertion space 122 will be described.

[0170] In order to insert the handle portion 520 of the tool holder 510 into the handle portion insertion space 122, it is necessary to set the collet 300 to the release mode.

[0171] In the case where it is desired to set the collet 300 to the release mode, the rotating member 410 of the drive mechanism 400 is caused to rotate in the other direction, for example, the clockwise direction. When the rotating member 410 rotates in the other direction, the movable member 430 moves to the side of the sealed space 131 (in a direction in which the volume of the sealed space 131 decreases) along the center line H2. Due to this, the pressure in the sealed space 121 of the clamping mechanism 200 increases, and the movable member 210 moves to the side opposite to the sealed space 121 (in a direction in which the volume of the sealed space 121 increases) against the elastic force of the disc spring 260.

[0172] Due to the movement of the movable member 210 to the side opposite to the sealed space 121, the abutment of the protruding portion 233 of the shaft member 230 and the collet member inner peripheral surface portion 311a of each collet member 310 is released.

[0173] At this time, since the movable member 210 moves to the side opposite to the sealed space 121, the spring 280 is compressed. Further, each collet member 310 constituting the collet 300 is held in a state of abutting against the main body portion inner peripheral surface portion 120d due to the elastic force of the spring 280.

[0174] In addition, due to the movement of the movable member 210 to the side opposite to the sealed space 121, the operation member 240 abuts against the protruding portion 313B of each collet member 310 (specifically, the operation member front end surface portion 240A2 and the collet member inner peripheral surface portion 311e abut against each other). Due to the abutment of the operation member 240 and the protruding portion 313B, the operation member 240 (the operation member front end surface portion 240A2) exerts a force to the protruding portion 313B (the collet member inner peripheral surface portion 311e) of each collet member 310 to move the protruding portion 313B to the outer peripheral side. Thus, the collet member inner peripheral surface portion 331b of each collet member 310 moves to the outer peripheral side (in a direction away from the shaft member 230) against the elastic force of the annular spring 270. At the same time, the collet member inner peripheral surface portion 331a and the protruding portion 313A move in a direction to approach the shaft member outer peripheral surface 232 (the shaft member outer peripheral surface portion 232d) of the shaft member 230 (refer to Figure 9 、 Figure 10 ).

[0175] Further, in a state where the collet 300 is set to the loosening mode, the shank portion 520 of the tool holder 510 is inserted into the shank insertion space 122. At this time, the protruding portion 313A of each collet member 310 is inserted into the shank inner side space 520a of the tool holder 510 (refer to Figure 11 ). In addition, the protruding portion 313A of each collet member 310 is disposed at a position opposite to the recessed portion 523 provided to the shank inner peripheral surface of the tool holder 510.

[0176] Further, the maximum outer diameter H of the protruding portion 313A of each collet member 310 in a state where the collet 300 is set to the loosening mode (refer to Figure 10 ) is set to be smaller than the inner diameter D of the shank inner side space 520a (refer to Figure 7 ) (H < D).

[0177] Next, the operation of clamping the tool holder 510 will be described with reference to Figure 12 、 Figure 13 .

[0178] In a state where the shank portion 520 of the tool holder 510 is inserted into the shank insertion space 122, the collet 300 is set to the clamping mode.

[0179] As described above, in the case where the collet 300 is to be set to the clamping mode, the rotating member 410 of the drive mechanism 400 is rotated in one direction, and the movable member 430 is moved along the center line H2 to the side opposite to the sealed space 131. Thus, the movable member 210 of the clamping mechanism 200 is moved along the center line Hl to the side of the sealed space 121 due to the elastic force of the disc spring 260.

[0180] As the movable member 210 of the clamping mechanism 200 is moved to the side of the sealed space 121, the abutment of the shaft member 230 and the protrusion 313B of each collet member 310 is released. Also, the collet member inner peripheral surface portion 311b of each collet member 310 is brought close to the shaft member outer peripheral surface 232 due to the elastic force of the ring spring 270. At the same time, the collet member inner peripheral surface portion 311a and the protrusion 313A are moved to the outer peripheral side (away from the shaft member outer peripheral surface 232). As the protrusion 313A is moved to the outer peripheral side, the protrusion 313A is engaged with the recess 523 of the tool holder 510. Further, the protrusion 233 of the shaft member 230 is in abutment with a portion of the collet member inner peripheral surface portion 311a, whereby a force acting to move the protrusion 233 to the outer peripheral side is generated. Thus, the clamping force can be increased.

[0181] Further, the movement of the protrusion 313A to the outer peripheral side is limited by the engagement of the protrusion 313A with the recess 523 of the tool holder 510.

[0182] In the clamping device 100 of the first embodiment, the extension direction of the main body portion inside space 120 (center line Hl) in which the clamping mechanism 200 is disposed and the extension direction of the main body portion inside space 130 (center line H2) in which the drive mechanism 400 is disposed are orthogonal, but the extension direction of the main body portion inside space 120 and the extension direction of the main body portion inside space 130 can be appropriately set.

[0183] Figure 14 A clamping device of the second embodiment is shown. The clamping device 100 of the second embodiment is the same structure as the clamping device 100 of the first embodiment except that the extension direction of the main body portion inside space 120 (center line Hl) and the extension direction of the main body portion inside space 130 (H2) are parallel and the shape of the communication path 140 is different.

[0184] In the present application, a sealed space filled with a power transmission medium is used as a power transmission mechanism between the drive mechanism and the clamping mechanism, and thus is inexpensive and can be easily configured. In particular, in the case where the extension direction of the main body portion inside space in which the drive mechanism is disposed and the extension direction of the main body portion inside space in which the clamping mechanism is disposed are to be changed, only the main body portion inside space and the communication path formed in the main body portion need to be changed, and thus design changes are easy.

[0185] Figure 15 、 Figure 16 Another embodiment of a collet 600 in which the shape of a gap formed between two collet members adjacent in the circumferential direction is changed is shown.

[0186] The collet 600 is composed of a plurality of collet members 610, like the collet 300.

[0187] The collet members 610 are arranged in the circumferential direction on the outer peripheral side of the shaft member outer peripheral surface portion 232d of the shaft member 230 of the movable member 210. Also, like the collet 300, the elastic force of the annular spring 270 acts as a force that causes the collet member inner peripheral surface portion 611b of each collet member 610 to approach the shaft member outer peripheral surface portion 232d and causes the collet member inner peripheral surface portion 611a and the protrusion 613A to move to the outer peripheral side (away from the shaft member outer peripheral surface portion 232d).

[0188] Also, when viewed in a cross section in the direction of extension of the shaft member 230 (center line P), a gap 616 is formed between two collet members 610 adjacent in the circumferential direction in a state in which the direction of extension of the collet member inner peripheral surface portion 611b of each collet member 610 is parallel to the direction of extension of the shaft member outer peripheral surface portion 232d. The gap 616 has a gap 616A and a gap 616B. The gap 616A is formed on the front end side compared to the gap 616B.

[0189] The gap 616B extends along the center line P with a spacing W. Also, the gap 616A extends along the center line P in a manner in which the spacing from the rear end side toward the front end side becomes a spacing V (V > W) that is wider than the spacing W from the spacing W.

[0190] Specifically, the collet member side surface 615 of each collet member 610 has a collet member side surface portion 615a and a collet member side surface portion 615b. The collet member side surface portion 615b extends parallel (including "approximately parallel") to the center line P, and the collet member side surface portion 615a extends in a direction inclined with respect to the direction of extension of the collet member side surface portion 615b (see FIG. 6). Figure 15 ).

[0191] The collet 600 of the present embodiment also has the same effects as the collet 300.

[0192] The gap 616B corresponds to the "first gap between collet members formed on the rear end side" of the present invention, and the gap 616A corresponds to the "second gap between collet members formed on the front end side" of the present invention.

[0193] The present invention is not limited to the structures described in the embodiments and various modifications, additions, and deletions can be made.

[0194] In the embodiment, the clamping device that clamps the tool holder having a shank and holding a tool is described, but the present application can be configured as a clamping device that clamps various clamped members such as a tool having a shank. That is, the "clamped member" includes a tool holder having a shank and holding a tool, a tool having a shank, and the like.

[0195] The shapes of the main body portion inside space in which the clamping mechanism is arranged (first main body portion inside space) and the main body portion inside space in which the driving mechanism is arranged (second main body portion inside space) are not limited to the shapes described in the embodiment.

[0196] The shapes and structures of the movable member (piston, shaft member, action member, pressing member), disc spring, ring spring, spring, collet, and the like that constitute the clamping mechanism are not limited to the shapes and structures described in the embodiment.

[0197] In the embodiment, the clamping mechanism is constituted by the movable member (piston, shaft member, action member, pressing member), disc spring, ring spring, spring, and collet, but the members that constitute the clamping mechanism are not limited thereto.

[0198] In the embodiment, the movable member (first movable member) of the clamping mechanism is constituted by the piston, shaft member, action member, and pressing member, but the structure of the movable member (first movable member) is not limited thereto. In addition, the movable member (first movable member) can be constituted by one member or by a plurality of members combined.

[0199] The shapes and structures of the rotating member, movable member (shaft member and piston), and the like that constitute the driving mechanism are not limited to the shapes and structures described in the embodiment.

[0200] In the embodiment, the driving mechanism is constituted by the rotating member and movable member (shaft member and piston), but the members that constitute the driving mechanism are not limited thereto.

[0201] In the embodiment, the movable member (second movable member) of the driving mechanism is constituted by the piston and shaft member, but the structure of the movable member (second movable member) is not limited thereto. In addition, the movable member (second movable member) can be constituted by one member or by a plurality of members combined.

[0202] Various known elastic members can be used as the elastic member.

[0203] The protrusions (first protrusion, second protrusion) of the collet member, the protrusions of the shaft member, disc spring, ring spring, spring, and the like can be appropriately selected as needed.

[0204] Each of the structures explained in the embodiments can be used alone, or can be used by combining a plurality of structures appropriately selected.

[0205] BRIEF DESCRIPTION OF DRAWINGS

[0206] 100, clamp device; 110, main body portion; 120, main body portion inner space (1st main body portion inner space); 120a to 120l, main body portion inner peripheral surface portions; 121, closed space (1st chamber); 122, shank portion insertion space; 130, main body portion inner space (2nd main body portion inner space); 130a to 130i, main body portion inner peripheral surface portions; 131, closed space (2nd chamber); 140, communication path; 200, clamping mechanism; 210, movable member (1st movable member); 220, piston (1st piston); 220A, piston front end surface; 220B, piston rear end surface; 222, piston outer peripheral surface; 223, O-ring (sealing member); 230, shaft member (1st shaft member); 230A, shaft member front end surface; 230B, shaft member rear end surface; 232, shaft member outer peripheral surface; 232a to 232d, shaft member outer peripheral surface portions; 233, protruding portion; 240, operation member; 240A, operation member front end surface; 240A1 to 240A3, operation member front end surface portions; 240B, operation member rear end surface; 241, operation member inner peripheral surface; 241a to 241e, operation member inner peripheral surface portions; 242, operation member outer peripheral surface; 242a to 242e, operation member outer peripheral surface portions; 250, pressing member; 250A, pressing member front end surface; 250B, pressing member rear end surface; 252, pressing member outer peripheral surface; 252a to 252c, pressing member outer peripheral surface portions; 260, disc spring (1st elastic member); 270, ring spring (diameter-reducing spring) (2nd elastic member); 280, spring (3rd elastic member); 300, collet; 310, collet member; 310A, collet member front end surface; 310B, collet member rear end surface; 310a, collet member inner space; 311, collet member inner peripheral surface; 311a to 311e, collet member inner peripheral surface portions; 312, collet member outer peripheral surface; 312a to 312h, collet member outer peripheral surface portions; 313A, protruding portion (1st protruding portion); 313B, protruding portion (2nd protruding portion); 315, collet member side surface; 315a to 315c, collet member side surface portions; 316A, 316B, gaps; 400, drive mechanism; 410, rotation member; 410A, rotation member front end surface; 411, rotation member inner peripheral surface; 411a to 411d, rotation member inner peripheral surface portions; 412, rotation member outer peripheral surface; 420, bearing member; 430, movable member (2nd movable member); 440, shaft member (2nd shaft member); 440A, shaft member front end surface; 440B, shaft member rear end surface; 442, shaft member outer peripheral surface; 442a to 442f, shaft member outer peripheral surface portions; 450, piston (2nd piston); 450A, piston front end surface; 450B, piston rear end surface; 452, piston outer peripheral surface; 453, O-ring (sealing member); 460, rotation-stopping member; 510, tool holder (clamped member);510a, tool holder inner side space; 510B, tool holder rear end face; 511, tool holder inner peripheral surface; 511a-511f, tool holder inner peripheral surface portions; 512, tool holder outer peripheral surface; 512a-512c, tool holder outer peripheral surface portions; 520, shank; 520a, shank inner side space; 523, recess; 550, tool.

Claims

1. A chuck device that chucks a chuck object having a shank portion in which a recess is formed, characterized by comprising: the chuck device is configured so that, the chuck device has a main body portion, a chuck mechanism, and a drive mechanism, the main body portion has a first main body portion inner space, a second main body portion inner space, and a communication passage, the chuck mechanism has a first movable member that is movable in an extension direction of the first main body portion inner space, a first chamber whose volume changes in accordance with movement of the first movable member, a first elastic member that generates an elastic force that moves the first movable member in a direction in which the volume of the first chamber decreases with respect to the main body portion, and a collet that has a first protrusion portion that is engageable with the recess of the chuck object, when the first movable member moves in a direction in which the volume of the first chamber decreases, the collet is set to a chucking mode in which the first protrusion portion and the recess are engaged, and when the first movable member moves in a direction in which the volume of the first chamber increases, the collet is set to a releasing mode in which engagement of the first protrusion portion and the recess is released, the drive mechanism has a second movable member that is movable in an extension direction of the second main body portion inner space, and a second chamber whose volume changes in accordance with movement of the second movable member, the communication passage communicates the first chamber and the second chamber, the first chamber, the second chamber, and the communication passage are filled with a power transmission medium, a cross-sectional area of the first chamber is set to be larger than a cross-sectional area of the second chamber, when the second movable member moves in a direction in which the volume of the second chamber increases, the first movable member moves in a direction in which the volume of the first chamber decreases due to the elastic force of the first elastic member, and the collet is set to the chucking mode, and when the second movable member moves in a direction in which the volume of the second chamber decreases, the first movable member moves in a direction in which the volume of the first chamber increases against the elastic force of the first elastic member, and the collet is set to the releasing mode.

2. The chuck device according to claim 1, characterized in that, the chuck device is configured so that, the drive mechanism has a rotation member, the second movable member is configured to be movable in the extension direction of the second main body portion inner space in linkage with rotation of the rotation member, when the rotation member is caused to rotate in one direction, the second movable member moves in a direction in which the volume of the second chamber increases, and when the rotation member is caused to rotate in the other direction, the second movable member moves in a direction in which the volume of the second chamber decreases.

3. The chuck device according to claim 1 or 2, characterized in that, the chuck device is configured so that, the shank portion of the chuck object has a shank portion inner peripheral surface that forms a shank portion inner space that is open at one end side, and the recess is formed in the shank portion inner peripheral surface, The first movable member has a first piston that forms the first chamber, and a first shaft member that is provided on the side opposite the first chamber with respect to the first piston and extends along the extension direction of the first body portion inside space, The collet has a plurality of collet members arranged along the circumference on the outer peripheral side of the first shaft member, Each of the collet members has a collet member inner peripheral surface and a collet member outer peripheral surface, and the first protruding portion protrudes outward from the end portion on the side opposite the first chamber of each of the collet members, When viewed in a cross section along the extension direction of the first shaft member, the collet member inner peripheral surface has a first collet member inner peripheral surface portion, and a second collet member inner peripheral surface portion that is formed on the side opposite the first chamber with respect to the first collet member inner peripheral surface portion and extends at an inclination angle θ with respect to the extension direction of the first collet member inner peripheral surface portion, the inclination angle θ being set such that the interval between the extension line of the first collet member inner peripheral surface portion and the second collet member inner peripheral surface portion increases from the side of the first chamber toward the side opposite the first chamber, When the first piston moves in the direction in which the volume of the first chamber decreases, the first collet member inner peripheral surface portion of each of the collet members approaches the first shaft member, and the collet is set to the clamped mode, and when the first piston moves in the direction in which the volume of the first chamber increases, the second collet member inner peripheral surface portion of each of the collet members approaches the first shaft member, and the collet is set to the released mode.

4. The clamping device according to claim 3, wherein the clamping device is configured such that the clamping mechanism has a second elastic member, the second elastic member generates an elastic force that causes the first collet member inner peripheral surface portion of each of the collet members to approach the first shaft member, when the first piston moves in the direction in which the volume of the first chamber decreases, the first collet member inner peripheral surface portion of each of the collet members approaches the first shaft member due to the elastic force of the second elastic member, and when the first piston moves in the direction in which the volume of the first chamber increases, the second collet member inner peripheral surface portion of each of the collet members approaches the first shaft member against the elastic force of the second elastic member.

5. The clamping device according to claim 4, wherein the clamping device is configured such that each of the collet members has a second protruding portion that protrudes outward on the outer peripheral side of the end portion on the side of the first chamber, the first shaft member has an abutting portion that is capable of abutting against the second protruding portion of each of the collet members, When the first piston moves in a direction in which the volume of the first chamber decreases, the abutment of the abutment portion of the first movable member and the second protruding portion of each collet member is released, and the first collet member inner peripheral surface portion of each collet member approaches the first shaft member due to the elastic force of the second elastic member, and when the first piston moves in a direction in which the volume of the first chamber increases, the abutment portion of the first movable member abuts against the second protruding portion of each collet member, a force that moves the second protruding portion to the outer peripheral side is applied, and thus the second collet member inner peripheral surface portion of each collet member approaches the first shaft member against the elastic force of the second elastic member.

6. The collet chuck according to any one of claims 3 to 5, characterized in that the collet chuck is configured so that the first shaft member has a protruding portion that protrudes to the outer peripheral side at an end portion on the side opposite the first chamber, when the first piston moves in a direction in which the volume of the first chamber decreases, the protruding portion of the first shaft member abuts against a portion of the second collet member inner peripheral surface portion of each collet member, a force that moves the second collet member inner peripheral surface portion away from the first shaft member is applied, and when the first piston moves in a direction in which the volume of the first chamber increases, the abutment of the protruding portion of the first shaft member and the portion of the second collet member inner peripheral surface portion of each collet member is released.

7. The collet chuck according to any one of claims 3 to 6, characterized in that the collet chuck is configured so that the main body portion has a movement restriction portion at a predetermined position that restricts movement of each collet member in a direction in which the volume of the first chamber increases, the collet mechanism has a third elastic member, the third elastic member generates an elastic force that separates the first movable member and each collet member.

8. The collet chuck according to claim 2, characterized in that the collet chuck is configured so that the second movable member has a second piston that forms the second chamber, and a second shaft member that is provided on the side opposite the second chamber with respect to the second piston and extends along the extension direction of the second main body portion inner side space, and the second shaft member is movable along the extension direction of the second main body portion inner side space in conjunction with the rotation of the rotation member.

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