JP2826107B2 - Ultra-precision chuck - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chuck for grasping a workpiece in a machine tool or the like, and in particular, to an ultra-precision chuck capable of extremely stably grasping a workpiece. About. [Prior art and its problems] Conventionally, a sliding member formed with a wedge is movably disposed in an axial center hole of a body, and is disposed in a radial guide groove formed radially in a radial direction of the body. A chuck in which a jaw engaging with a wedge of the sliding member is slidably fitted, and the jaw is moved in a radial direction by a wedge action accompanying the axial movement of the sliding member,
Various types are known, and an example of such a conventional type is described in German Patent Application Publication No. 3006786. In this chuck, the wedge groove of the master jaw is formed in a guided projection fitted into the T-shaped guide groove of the chuck body, and the axial length of the master jaw is shortened by such a configuration to reduce the weight. It is a measure. However, in this conventional chuck, the twelfth
As shown in the figure, the action position of the wedge and the workpiece grasping position are not located within the support range of the wedge of the sliding member by the body indicated by the black triangle, and the action position indicated by the white arrow is out of the support range. The wedge will be cantilevered by the body. As a result, the front portion of the wedge and the master jaw tilt due to the bending moment, and a stable tightening force on the workpiece cannot be obtained. [Object of the Invention] The present invention overcomes such problems in the prior art and provides an ultra-precision chuck capable of supporting a sliding member by a body without a bending moment acting on a wedge and a jaw. The purpose is to provide. [Summary of the Invention] In order to achieve the above-mentioned object, a first aspect of the present invention relates to a body, a sliding member movably arranged in an axial direction of the body, and a guide formed in a radial direction of the body. A slidably inserted jaw, and the jaw has a grasping portion in at least one of an outer side and an inner side of a wedge groove of the jaw in a radial direction of the body. A chuck that opens and closes in a radially outward and inward direction of the body by a wedge action accompanying the directional movement, wherein the body has an axial wedge insertion hole having an inner peripheral surface that supports the sliding member, A plurality of sliding members are disposed in the wedge insertion hole at intervals in the circumferential direction of the body, and each sliding member has a base and a projecting member extending from the base in the axial direction of the body. With the established support The wedge formed on the side of the jaw, the wedge formed on the side corresponding to the jaw in the circumferential direction of the body. The sliding member on the opposite side of the wedge is provided with the support portion, the support portion is provided with a sliding surface that is inserted and supported in a wedge insertion hole of the body, and is provided in the axial direction of the body. At the same time always supported on both front and rear sides of the wedge groove of the jaw, position the grip of the jaw within its support range,
The jaw is provided with one wedge groove on a side surface thereof. According to such a configuration, the grasping portion that grasps the working position of the wedge with respect to the wedge groove of the jaw and the workpiece is located between both ends of the support portion that is so-called both ends supported by the body in the body axis direction. Because
No bending moment acts on both the wedge and jaw members in the body axis direction.
The wedge and the jaw do not tilt, and a stable tightening force can be obtained for the workpiece. According to a second aspect of the present invention, in the configuration of the first aspect described above, the operation position of the wedge of the jaw and the grasping position of the workpiece in the circumferential direction of the body are located between the support portions of the body. Is added. According to such a configuration, since different bending moments do not act on the wedge even in the circumferential direction of the body, the bending moment does not act on the jaw, and a more stable tightening force is obtained on the workpiece. be able to. Further, the third aspect of the present invention is characterized in that, in addition to the configuration of the above-described second aspect of the present invention, a configuration is adopted in which a distal end side separated from the base of the sliding member toward the axial front side of the body is joined. It is characterized by. According to such a configuration, no bending moment acts on the jaw even in the circumferential direction of the body, and the rigidity of the sliding member can be further increased, so that a more stable fastening to the workpiece can be achieved. You can gain power. Hereinafter, the present invention will be described with reference to embodiments shown in the drawings. FIGS. 1 and 2 show a first embodiment of an ultra-precision chuck according to the present invention, wherein a first hole of a body 1 formed as a whole by an axially extending central hole 2 is formed. In the figure, the right end in the axial direction
3 cylindrical guides 3,3,3 radially spaced at an interval of degrees
Are formed. In addition, three flat wedges extending in parallel with the axial direction of the body 1 from the base end, which is the left side in FIG. Insertion holes 4, 4, 4 are formed, and each wedge insertion hole 4 has a width in the radial direction parallel to the circumferential direction of the body 1 as shown in detail in FIG. Project laterally from both ends. In the base end of the body 1, three communication openings 5, which allow each wedge insertion hole 4 to communicate with the center hole 2,
5,5 are formed. A cylindrical plunger 6 is slidably disposed in the center hole 2. The plunger 6 has a protruding 3 that faces into each wedge insertion hole 4 through each communication opening 5.
The two pistons 7, 7, 7 project from each other at an interval of 120 degrees. On the inner peripheral surface of the plunger 6, an inner screw 8 for connecting the plunger 6 to an actuator (not shown) is formed. As shown in FIGS. 4A, 4B, and 4C, for example, a thick cylindrical master jaw 9 is slidably inserted into each of the guide portions 3, and both sides of the outer peripheral surface of the master jaw 9 are provided. Are formed in parallel with each other, wedge grooves 10, 10 inclined with respect to the axial direction of the body 1 so as to be mirror-symmetrical. When the outer diameter of the workpiece is to be grasped, the end face of the master jaw 9 located on the body 1 and the center hole 2 side.
9A is curved in accordance with the curvature of the center hole 2 as shown in FIG. 4C, and is screwed to the end face 9A by a mounting bolt 11 inserted into the center hole 9C of the master jaw 9. Pad 12 is in contact therewith. On the other hand, a pair of wedges 14, 14 fitted into the two wedge grooves 10, 10 of the master jaw 9 are formed on a sliding member 13, as shown in FIG. That is, the sliding member 13 and the base portion 15 and a pair of support portions 16 and 16 having a rectangular cross section projecting in parallel from the base portion 15 are formed in a U-shape as a whole. The portions 16 and 16 have sliding surfaces formed so as to be able to swing relatively densely with the inner peripheral surface of the wedge insertion hole 4 of the body 1.
The interval between 6, 16 is formed to be substantially equal to the outer diameter of the master jaw 9. And these support parts 1
Inside the wedge insertion holes 4, the wedges 14, 14 having an inclination angle equal to the inclination angle of each wedge groove 10 with respect to the longitudinal direction in the axial direction of the body 1 of the wedge insertion hole 4 are provided on the axis of the body 1 of the support 16. Each wedge 14 has a thickness such that the body 1 can slide relatively densely in the wedge groove 10.
Is formed to have dimensions substantially equal to the width of the wedge groove 10 of the master jaw 9 in the axial direction. Further, on the front side of the base portion 15, a reinforcing piece 17 for reinforcing each wedge 14 integrally with the two wedges 14, 14 is provided so as to protrude. Further, a long groove 18 into which the protrusion of the piston 7 can be fitted relatively densely is formed on the communication opening 5 side of the base 15 in a direction perpendicular to the longitudinal direction of the wedge insertion hole 4. The body 1 is formed with a bolt insertion hole 19 extending parallel to the center hole 2 thereof.
Inside 19, mounting bolts 20 for fixing the ultra-precision chuck are inserted. Next, the operation of this embodiment having the above-described configuration will be described. To assemble the ultra-precision chuck as shown in FIG.
After inserting the master jaws 9 into the respective guide portions 3, a pad (grasping portion) 12 for grasping a workpiece so as to cover the end face 9A of each master jaw 9 is attached. On the other hand, the projection of each piston 7 of the plunger 6 has a long groove of each sliding member 13.
18 and fit the plunger 6 into the center hole 2 of the body 1.
And each sliding member 13 is simultaneously inserted into each wedge insertion hole 4, and a pair of wedges of each sliding member 13 is inserted.
14 and 14 are fitted into the wedge grooves 10 and 10 of the master jaw 9 so that the master jaw 9 is held therebetween (FIG. 5).
A, B). When an ultra-precision chuck as shown in FIG. 1 is formed in this way, a workpiece (not shown) is inserted into the center hole 2 of the body 1 and the plunger 6 is moved leftward in FIG. Each sliding member 13 in which the long groove 18 is fitted to each piston 7 of the plunger 6 also moves to the left along with the plunger 6, and the wedge 1 provided on each sliding member 13 is provided.
Since each master jaw 9 moves inward in the radial direction of the body 1 by the wedge action of the wedge grooves 10 and 10 of each master jaw 9, the workpiece 12 is moved outside by the pad 12 of each master jaw 9. You can figure out. On the other hand, although not shown, in order to grasp the inner diameter of the workpiece, a pad is attached to the end face 9B of each master jaw 9 located on the outer peripheral side of the body 1 and the plunger 6 is moved rightward in FIG. Wedge of each sliding member 13
Since each master jaw 9 moves outward in the radial direction of the body 1 by the wedge action of the wedge grooves 10 and 10 of each master jaw 9, the inner diameter of the workpiece is grasped by the pad of each master jaw 9. be able to. By the way, the sliding surfaces of the pair of support portions 16 and 16 protruding from each sliding member 13 cover the entire area in the longitudinal direction by the inner peripheral surface of the wedge insertion hole 4 of the body 1 when the outer diameter is grasped. Each of the support portions 16 is supported from the outside of the body 1 on the inner peripheral surface of the wedge insertion hole 4 of the body 1 and from the inside when grasping the inner diameter.
Wedge groove of master jaw 9 integral with wedge 14
The position of operation with respect to 10 is within a range in which the support portions 16, 16 are supported by the body in the body axial direction. Therefore, the wedges 14, 14 are supported at both ends as shown in FIG. 11, and each wedge 14 acts on the wedge groove 10 of the master jaw 9 within the range where both ends are supported. No bending moment acts on the sliding member 13 separating the sliding member 14. As a result, the sliding member 13 does not tilt, and a stable tightening force can be obtained on the workpiece. On the other hand, since the pad (grasping portion) 12 for grasping the workpiece is located substantially inside and outside the wedge groove 10 of the master jaw 9 in the radial direction of the body 1 (FIG. The gripping operation position is the same as the operation position of the wedge 14 with respect to the wedge groove 10 of the master jaw 9.
Within the range supported by Therefore, the master jaw 9 also moves in the axial direction of the body 1.
As shown in FIG. 11, since both ends are supported, no bending moment acts on the master jaw 9, so that the master jaw 9 does not tilt, so that the master jaw 9 is more stably fastened to the workpiece. An urging force can be obtained. In the body circumferential direction, the wedge 14 receives a bending moment due to the force acting on the wedge 14,
Since the wedges 14 are located at opposite positions, the bending moments generated in the two wedges 14 and 14 are substantially the same. Therefore, the master jaw 9 does not tilt even in the circumferential direction. 6 and 7 show a second embodiment of the ultra-precision chuck according to the present invention. The same components as those of the conventional one described above are denoted by the same reference numerals in the drawings, and the description thereof will be omitted. Is omitted. In FIG. 6, a sliding member 21 which is movable in the wedge insertion hole 4 of the body 1 is provided, and the sliding member 21 includes a base 22 and a pair of supporting portions 23, 23. Wedge 2
4 and is formed. Flat wedge 24 is base 2
It is stretched inside 2 and both support parts 23,23. As shown in detail in FIG. 8, the wedge 24 is formed so as to be inclined in the moving direction of the sliding member 21 so that the tip side of the body 1 is closer to the center of the body 1. An elongated hole 25 extending in the moving direction of the sliding member 21 is formed at the center in the width direction of the sliding member 21. In addition, this wedge
A supported surface 23A, which is supported by the body 1 by connecting the two support portions 23, 23, is formed on the distal end side of 24. On the other hand, a radially formed guide portion 27 of the body 1 into which a master jaw 26 to be described later is fitted is formed so as to intersect with the wedge insertion hole 4.
Is composed of a large diameter hole 28 located inside the wedge insertion hole 4 in the radial direction of the body 1 and a small diameter hole 29 located outside the wedge insertion hole 4 and formed concentrically with the large diameter hole 28. ing. The master jaw 26 has a body 1
A first cylindrical body 30 located inside the wedge 24 and slidable along the large-diameter hole 28 in the radial direction, and a second cylindrical body located outside the wedge 24 and slidable along the small-diameter hole 29. An end face 30A of the first cylinder 30 and an end face 31A of the second cylinder 31 joined to the wedge 24 form a wedge surface having the same inclination as the wedge 24, respectively. I have. Further, a first member located on the side of the center hole 2 of the body 1 is provided.
As shown in FIG. 9, the end surface 30B of the cylindrical body 30 is curved in accordance with the curvature of the center hole 2, and the end surface 30B of the first cylindrical body 30 is bent.
The end surface 32A of the pad 32 abutting on the end surface is curved so as to have a curvature equal to the curvature of the end surface 30B as shown in FIG. 10, and the end surface 32B of the pad 32 It is curved so as to have a curvature equal to the curvature of the diameter. Then, after the mounting bolt 11 is inserted from the outer peripheral side of the body 1 into the center hole 31C of the second cylindrical body 31, the mounting bolt 11 is inserted into the long hole 25 of the wedge 24 of the sliding member 21. By inserting the bolt 11 into the center hole 30C of the first cylindrical body 30 and screwing it to the pad 32, the master jaw 26 is assembled so as to be relatively movable with respect to the sliding member 21. Next, the operation of this embodiment having the above-described configuration will be described. When a workpiece is inserted into the center hole 2 of the body 1 and the plunger 6 is moved to the left in FIG. 6, each sliding member 21 in which the long groove 18 is fitted to each piston 7 of the plunger 6.
Also moves to the left with the plunger 6, and each sliding member 21
The wedge 24 and the first cylindrical body 3 stretched on the support portions 23
Each master jaw 26 by wedge action with 0 wedge surface 30A
Moves inward in the radial direction of the body 1 so that each pad 32
Thus, the outer diameter of the workpiece can be grasped. In order to grasp the inside diameter of the workpiece (not shown), a pad is attached to the end face 31B of the second cylindrical body 31 located on the outer peripheral side of the body 1, and then the plunger 6 is moved rightward in FIG. Then, contrary to the above, each master jaw 26 can be moved outward in the radial direction, and the inner diameter can be grasped by each pad. According to the present embodiment, as in the first embodiment described above, the plate-like wedge 24 of each sliding member 21 is attached to the base 22 of each sliding member 21.
Both sides are fixed to both support portions 23, 23 protruding from the inner surface of the wedge insertion hole 4 of the body 1 when the outer diameter of the entire region in the longitudinal direction is grasped. When the inside diameter is grasped, the wedge 24 is supported from the outside of the body 1 by the inner side when the inner diameter is grasped. 1 is within the range supported by. On the other hand, a pad (grasping portion) 32 for grasping the workpiece is provided with a master jaw in the radial direction of the body 1.
26 are located substantially inside and outside the first cylinder 30 and the second cylinder 31,
Similarly to the position where the wedge 24 acts on the wedge surface of the master jaw 26, each support portion 23 is within a range where the support portion 23 is supported by the body 1. Therefore, the sliding member 21
No bending moment acts on the master jaw 26 and the master jaw 26, and a stable tightening force can be obtained on the workpiece. Further, in the present embodiment, the two supporting portions 23, 23 of the sliding member 21 are also joined in the circumferential direction of the body 1, so that the supported surface supported on the inner circumferential surface of the wedge insertion hole 4 of the body 1 is supported. twenty three
Since the A is formed, the two support portions 23, 23 are integrally formed in the circumferential direction, and the wedge 24 is formed on the wedge surface of the master jaw 26 within a range of both ends supported by both ends in the circumferential direction of the body 1. And the gripping part of the workpiece is also located, so the sliding member
Since no bending moment acts on the master jaw 21 and the master jaw 26, a more stable tightening force can be obtained on the workpiece also in this respect. Note that the present invention is not limited to the above-described embodiments, and various modifications can be made as necessary. [Effect of the Invention] As described above, the first aspect of the present invention provides a body,
A sliding member movably arranged in the axial direction of the body, and a jaw slidably fitted in a guide portion formed in a radial direction of the body. A chuck provided with a grasping portion substantially at least one of an outer side and an inner side of a wedge groove of the jaw, and opening and closing the jaw outward and inward in a radial direction of the body by a wedge action accompanying the axial movement of the sliding member. hand,
The body has an axial wedge insertion hole having an inner peripheral surface for supporting the sliding member, and a plurality of sliding members are arranged in the wedge insertion hole at intervals in a circumferential direction of the body. Each of the sliding members includes a base, a support protruding from the base in the axial direction of the body, and a wedge formed on the support, and a circumference of the body. The sliding member on the side facing the jaw in the direction includes the wedge fitted into a wedge groove on the side surface of the jaw, and the sliding member on the opposite side of the wedge includes the support portion. An axial length of the wedge is formed much longer than an axial length of a wedge groove of the jaw, and the support portion has a sliding surface inserted and supported in a wedge insertion hole of the body, and Axial direction The jaw is always supported on both front and rear sides of the wedge groove of the jaw. Since the jaw has one wedge groove on its side surface, between both ends of the support portion supported at both ends by the body in the body axial direction, Since the grip position for grasping the position of the wedge acting on the wedge groove of the jaw and the workpiece is located, no bending moment acts on both members of the wedge and the jaw. A stable tightening force can be obtained on the workpiece without tilting the workpiece. According to a second aspect of the present invention, in addition to the configuration of the first aspect, since a different bending moment does not act on the wedge in the circumferential direction of the body, a bending moment is generated in the jaw. Therefore, it is possible to obtain a more stable tightening force having high gripping accuracy with a large tightening force on the workpiece. Further, in the third invention of the present application, since the distal end side separated from the base of the sliding member toward the front side in the axial direction of the body is connected, the bending moment is applied to the jaw in the circumferential direction of the body. Does not act, and the rigidity of the sliding member can be further increased, so that a large clamping force and a high grasping accuracy can be obtained more stably with respect to the workpiece.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 to 6 show a first embodiment of an ultra-precision chuck according to the present invention, wherein FIG. 1 is a front view in vertical section, and FIG. FIG. 3 is a perspective view of a sliding member, FIG. 4A is a perspective view of a master jaw, FIG. 4B is a cross-sectional view taken along line IV-IV of FIG. 4A, FIG. C is 4th
FIG. 5A is a right side view, FIG. 5A is a perspective view showing a fitted state of a sliding member and a master jaw, FIG. 5B is a plan view of FIG. 5A, and FIGS. 6 is a longitudinal sectional front view, FIG. 7 is a partial longitudinal schematic side view of FIG. 6, FIG. 8 is an exploded perspective view of a sliding member and a master jaw, FIG. 9 is a side view of the first cylindrical body, FIG. 10 is a side view of the pad, FIG. 11 is a schematic view showing a support state of the wedge in the first embodiment of the present invention, and FIG. It is a schematic diagram which shows the support state of a wedge. 1 ... body, 2 ... center hole, 3, 27 ... guide part, 4 ...
Wedge insertion hole, 6, plunger, 9,26 master jaw, 1 ... wedge groove, 12, 32 sliding part (pad), 13, 21 sliding member, 14, 24 wedge , 15,22
... Base, 16, 23.
The second cylinder.

Claims (1)

(57) [Claims] A body, a sliding member movably arranged in the axial direction of the body, and a jaw slidably fitted in a guide formed in a radial direction of the body. A grasping portion is provided at least in at least one of the wedge grooves of the jaw in the direction, and the jaw is opened and closed radially outward and inward of the body by a wedge action accompanying the axial movement of the sliding member. A chuck, wherein the body has an axial wedge insertion hole having an inner peripheral surface for supporting the sliding member, and a plurality of slides in the wedge insertion hole at circumferentially spaced intervals of the body. A member is disposed, each sliding member is constituted by a base, a support protruding from the base in the axial direction of the body, and a wedge formed on the support, The body The sliding member on the side facing the jaw in the circumferential direction includes the wedge fitted into a wedge groove on a side surface of the jaw, and the sliding member on the opposite side of the wedge supports the wedge. The supporting portion has a sliding surface that is inserted and supported in a wedge insertion hole of the body, and is always supported on both front and rear sides of a wedge groove of a jaw in the axial direction of the body. An ultra-precision chuck wherein a support portion of the jaw is positioned within a support range, and the jaw has one wedge groove on a side surface thereof. 2. A body, a sliding member movably arranged in the axial direction of the body, and a jaw slidably fitted in a guide formed in a radial direction of the body. A grasping portion is provided at least in at least one of the wedge grooves of the jaw in the direction, and the jaw is opened and closed radially outward and inward of the body by a wedge action accompanying the axial movement of the sliding member. A chuck, wherein the body has an axial wedge insertion hole having an inner peripheral surface for supporting the sliding member, and a plurality of slides in the wedge insertion hole at circumferentially spaced intervals of the body. A member is provided, and each sliding member is configured by a base, a support protruding from the base in the axial direction of the body, and a wedge formed on the support, Each slide The members are shaped to face each other in the circumferential direction of the body with the jaw therebetween, and are fitted to wedge grooves respectively formed on both side surfaces of the jaw on the sliding members facing the jaw. A pair of the wedges to be combined with each other, and each of the sliding members on the opposite side of each of the wedges includes the supporting portion; and the supporting portion is inserted into and supported by a wedge insertion hole of the body. A moving surface is provided, and is always supported on both front and rear sides of a wedge groove of the jaw in the axial direction of the body, and the jaw gripping part is positioned within the support range. An ultra-precision chuck having a wedge groove. 3. 3. The ultra-precision chuck according to claim 2, wherein said jaw is formed in a substantially cylindrical shape. 4. 4. The ultra-precision chuck according to claim 2, wherein the sliding member is formed in a forked end shape. 5. The ultra-precision chuck according to any one of claims 2 to 4, wherein the jaw is formed detachably in a radial direction of the body. 6. A body, a sliding member movably arranged in the axial direction of the body, and a jaw slidably fitted in a guide formed in a radial direction of the body. A grasping portion is provided at least in at least one of the wedge grooves of the jaw in the direction, and the jaw is opened and closed radially outward and inward of the body by a wedge action accompanying the axial movement of the sliding member. A chuck, wherein the body has an axial wedge insertion hole having an inner peripheral surface for supporting the sliding member, and a plurality of slides in the wedge insertion hole at circumferentially spaced intervals of the body. A member is provided, and each sliding member includes a base, a support protruding from the base in an axial direction of the body, and a wedge formed on the support. With Each of the sliding members is opposed to each other in the circumferential direction of the body with the jaw therebetween, and has a shape in which a distal end side separated from the base to the front side in the axial direction of the body is combined, and faces the jaw. The sliding member on the side includes a pair of wedges fitted into wedge grooves formed on both side surfaces of the jaw, respectively. The sliding member on the opposite side of each wedge includes the pair of wedges. A support portion, the support portion includes a sliding surface that is inserted and supported in a wedge insertion hole of the body, and the support portion is always supported on both front and rear sides of a wedge groove of a jaw in the axial direction of the body. And, while being always supported on the left and right sides of the wedge groove in the circumferential direction of the body, the grip portion of the jaw is positioned within the support range, An ultra-precision chuck having two wedge grooves on a side surface. 7. 7. The ultra-precision chuck according to claim 6, wherein said jaw is formed in a substantially cylindrical shape. 8. The ultra-precision chuck according to claim 6 or 7, wherein the sliding member is formed in a rectangular shape having a base connected thereto. 9. The ultra-precision chuck according to any one of claims 6 to 8, wherein the jaw is detachably formed in a radial direction of the body.