WO2007132809A1

WO2007132809A1 - Work support

Info

Publication number: WO2007132809A1
Application number: PCT/JP2007/059858
Authority: WO
Inventors: Gaku Yoshimura
Original assignee: Kosmek Ltd.
Priority date: 2006-05-16
Filing date: 2007-05-14
Publication date: 2007-11-22
Also published as: JPWO2007132809A1

Abstract

A taper collet (10), which can expand and contract in the diameter direction, is fitted at the outside of a rod (4) movably inserted in a housing in a shaft center direction. The taper collet (10) is reduced in the diameter by many balls (B) arranged outside of the taper outer circumference surface (11) of the taper collet (10). On the inner circumference of the taper collet (10), straight inner circumference surfaces (41) to which the straight outer circumference surface (40) of the rod (4) abuts are arranged at intervals in the shaft center direction. A circumference groove (42) is arranged between the adjacent straight inner circumference surfaces (41, 41). The width dimension (w2) of the circumference groove (42) is set at a value of the width dimension (w1) of the straight inner circumference surface (41) or more but smaller than the diameter (d) of the balls (B).

Description

Specification

Work support

Technical field

The present invention relates to a work support used for a machine tool or the like, and is a technique suitable for gripping a support rod at a predetermined height position by a taper collet.

Background art

[0002] Conventionally, this type of work support is described in the following Patent Document 1 (Japanese Patent Laid-Open No. 10-146733).

In the prior art, a taper collet that can be expanded and contracted in the diameter direction is externally fitted to a rod that is inserted in a housing so as to be movable in the axial direction, and a large number of taper collets are arranged outside the taper outer peripheral surface. The taper collet is configured to be reduced in diameter by a ball.

In the above configuration, conventionally, a spiral groove is formed at a predetermined pitch on the inner periphery of the taper collet, and between the spiral grooves, the spiral straight is set to a width dimension larger than the width dimension of the same spiral groove. An inner peripheral surface was formed, and the straight inner peripheral surface was in contact with the straight outer peripheral surface of the rod.

Patent Document 1: Japanese Patent Laid-Open No. 10-146733

Disclosure of the invention

Problems to be solved by the invention

[0003] The above prior art is excellent in that the straight inner peripheral surface of the tape collet switched to the reduced diameter state is brought into contact with the straight outer peripheral surface of the rod and the rod can be gripped when the work support is locked. However, there has been a demand for further increasing the gripping force. However, if the surface pressure of the straight inner peripheral surface with respect to the straight outer peripheral surface is increased during the lock driving, the straight inner peripheral surface damages the straight outer peripheral surface, and the rod smoothly moves in the axial direction. There was a problem of being unable to move.

An object of the present invention is to achieve both a smooth movement of the work support rod and a significant increase in the gripping force of the rod. Means for solving the problem

[0004] In order to achieve the above object, according to the first invention, for example, as shown in FIGS. 1 and 2, the work support is configured as follows.

A taper collet (10) that can be expanded and contracted in the diameter direction is externally fitted to a rod (4) that is inserted into the housing (2) so as to be movable in the axial direction. The taper collet (10) is configured to be reduced in diameter by a large number of balls (B) arranged outside the taper outer peripheral surface (11) of the taper collet (10). A plurality of straight inner peripheral surfaces (41) that are in contact with the straight outer peripheral surface (40) of the rod (4) are provided on the inner periphery of the taper collet (10) at intervals in the axial direction. . A circumferential groove (42) is provided between adjacent straight inner circumferential surfaces (41X41). And the width dimension (w2) of the circumferential groove (42) is smaller than the diameter (d) of the ball (B) with a value equal to or greater than the width dimension (wl) of the straight inner circumferential surface (41), Set to value.

[0005] In the first invention described above, the straight inner peripheral surface (41) is preferably provided at substantially equal intervals in the axial direction in order to efficiently machine the tapered collet. You may change the installation space | interval of a surrounding surface. In this case, it can be considered that the width dimension of the straight inner peripheral surface or the circumferential groove is regularly changed (or irregularly changed) in the axial center direction of the taper collet.

[0006] The first invention described above has the following effects.

The width of the circumferential groove on the inner circumference of the taper collet is set to a value that is equal to or greater than the width of the straight inner circumference and smaller than the ball diameter. When the diameter of the taper collet is reduced, the ball prevents the inner circumference of the tape collet from becoming excessively inward in the radial direction, and the straight inner circumference surface of the rod is Can be pressed almost evenly. For this reason, it is possible to prevent the surface pressure on the straight inner peripheral surface from becoming excessively high during the lock driving, and to prevent the straight inner peripheral surface from damaging the straight outer peripheral surface. As a result, the mouth can be smoothly moved in the axial direction. Also, since the width of the straight inner circumferential surface is set to a value smaller than the width of the circumferential groove, a large surface pressure can be secured and the force for gripping the rod is greatly increased.

Therefore, the work support rod can be moved smoothly and the gripping force of the rod can be greatly increased. It was possible to increase both of them.

[0007] In order to achieve the above object, according to the second invention, for example, as shown in FIGS. 1 and 2, the single support is configured as follows.

A taper collet (10) that can be expanded and contracted in the diameter direction is externally fitted to a rod (4) that is inserted into the housing (2) so as to be movable in the axial direction. The taper collet (10) is configured to be reduced in diameter by a large number of balls (B) arranged outside the taper outer peripheral surface (11) of the taper collet (10). A circumferential groove (42) is provided in a spiral shape on the inner periphery of the taper collet (10), and the straight outer peripheral surface (40) of the rod (4) is in contact with the spiral circumferential groove (42). The straight inner peripheral surface (41) to be hit is provided in a spiral shape. The width dimension (w2) of the circumferential groove (42) was set to a value smaller than the diameter (d) of the ball (B) with a value equal to or greater than the width dimension (wl) of the straight inner circumferential surface (41). .

[0008] The second invention described above has the following operational effects as in the first invention.

Therefore, it was possible to achieve both the smooth movement of the work support rod and a significant increase in the gripping force of the rod.

[0009] In each of the above inventions, it is preferable that the width dimension (wl) of the straight inner peripheral surface (41) is set to a value equal to or more than half of the width dimension (w2) of the peripheral groove (42). .

In this case, since the straight inner peripheral surface can secure a large area, it is possible to prevent the surface pressure from becoming excessively high when the work support is driven to lock. Because of this, its straight inner circumference It is possible to reliably prevent the surface from damaging the straight outer peripheral surface of the rod. As a result, the rod can be smoothly moved in the axial direction over a long period of time.

[0010] In each of the above inventions, the average value of the minimum value (tl) and the maximum value (t2) of the radial thickness of the tapered outer peripheral surface (11) of the tapered collet (10) is: It is preferable to set a value larger than the diameter (d) of the ball (B).

In this case, sufficient rigidity can be ensured in the taper collet. Therefore, when the diameter of the taper collet is reduced through a large number of balls when the workpiece support is driven, the ball collides with the taper collet. The straight inner peripheral surface can be evenly pressed against the straight outer peripheral surface of the rod by reliably preventing the circumference from being excessively bent inward in the radial direction. For this reason, it is possible to prevent the surface inner peripheral surface from damaging the straight outer peripheral surface by preventing the surface pressure from becoming excessively high during the lock driving. As a result, it was ensured that the rod was smoothly moved in the axial direction over a long period of time. Brief Description of Drawings

FIG. 1 is a longitudinal sectional view of a work support according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of the main part of the work support.

Explanation of symbols

[0012] 2: Nosing, 4: Rod, 10: Tapered collet, 11: Tapered outer peripheral surface, 40: Straight outer peripheral surface, 41: Straight inner peripheral surface, 42: Circumferential groove, B: Ball, d: Ball B Diameter, tl: minimum thickness, t2: maximum thickness, wl: width of straight inner circumferential surface 41, w2: width of circumferential groove 42 Best Mode for Carrying Out the Invention

Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 and 2. Fig. 1 is a longitudinal sectional view of the work support. FIG. 2 is a schematic diagram of a cross-sectional view of the main part of the work support. In this embodiment, a structure in which the work support 1 is locked by oil pressure and released by panel force is illustrated.

The housing 2 of the work support 1 includes an upper end wall 2a, a lower end wall 2b, and a body portion 2c, and is fixed to the table T by a plurality of fastening bolts 3 (only one is shown here). A support rod 4 is inserted into the housing 2 so as to be movable in the vertical direction. That rock The door 4 is projected upward by the advance panel 5, and the attachment bolt 6 provided on the top of the rod 4 is brought into contact with the workpiece W. The protruding amount of the rod 4 can be regulated by the regulating bolt 7.

[0014] A gripping region A is provided in the lower half portion of the outer peripheral surface of the rod 4, and a cylindrical taper collet 10 that can be expanded and contracted in the radial direction is fitted on the gripping region A. The collet 10 has a tapered outer peripheral surface 11 having an upper concavity, and is adapted to be reduced in diameter by one slit 12 extending in the vertical direction. An annular transmission 14 is arranged on the outer peripheral side of the collet 10, and the tapered inner peripheral surface 15 of the transmission 14 is opposed to the taper outer peripheral surface 11 of the collet 10 on the upper side.

As shown in FIG. 1, the gradient α of the tapered outer peripheral surface 11 and the tapered inner peripheral surface 15 is set to be the same.

A large number of ball cages are inserted into the annular taper gap C formed between the tapered outer peripheral surface 11 and the tapered inner peripheral surface 15. These balls are inserted so as to be in contact with the circumferential direction of the annular taper gap C and stacked so as to be in contact with the axial direction.

The ball rods are pushed up by the pressing panel 17 to the upper flange 18 of the collet 10 and aligned. The collet 10 is pressed against the stopper 22 of the lower end wall 2b by the elastic force of the pressing rubber 20 and the upper sleeve 21, and is positioned in the unclamped lowered state. The pressing panel 17 and the pressing rubber 20 can be omitted.

[0016] A clamping piston 24 (first driving means F) protrudes radially outward from the transmission 14 and a hydraulic working chamber 25 is formed on the upper side of the piston 24 and a panel chamber on the lower side. 2 6 is formed. A pressure oil supply / discharge rod 27 communicates with the working chamber 25, and a return panel 28 (second drive means S) is attached to the panel chamber 26. A filter 30 is attached to the breathing passage 29 of the panel room 26.

[0017] The workpiece W is supported by the workpiece support 1 in the following procedure, for example.

In the released state shown in FIG. 1, the pressure oil is discharged from the hydraulic working chamber 25, the piston 24 and the transmission 14 are moved upward by the return panel 28 to release the diameter of the collet 10, and the servo rod 4 is moved to the advance panel. Projected upward by 5. In the released state, the work piece W is loaded with the upper force, and the main part of the work piece W is supported by a support base (not shown). The workpiece protruding portion shown in the figure is also brought into contact with the attachment bolt 6 of the support rod 4 with an upper force. As a result, the support rod 4 is retracted to the illustrated height position.

Thereafter, pressure oil is supplied into the hydraulic working chamber 25. Then, the transmission 14 is moved downward by the hydraulic pressure acting on the piston 24 from the working chamber 25, and the tapered inner peripheral surface 15 of the transmission 14 rolls the ball B while rolling the ball B. The collet 10 is smoothly engaged with the outer peripheral surface 11 and the diameter of the collet 10 received by the stopper 22 is reduced. As a result, the collet 10 having a reduced diameter presses the gripping area A of the support rod 4 in the centripetal direction, and fixes the support rod 4 at the height position shown in the figure.

The upper surface of the workpiece W is mechanically swung in the locked state, and the lower end of the housing 2 is pushed through the support rod 4, the gripping area A, and the collet 10 in order. It is received by wall 2b.

[0019] After the machining is completed, the pressure oil is discharged from the hydraulic working chamber 25. Then, the piston 24 and the transmission device 14 are pressed upward by the return panel 28, and the taper inner peripheral surface 15 of the transmission device 14 moves smoothly upward while rolling the ball B, and the taper of the collet 10 The pressed state of the outer peripheral surface 11 is released. As a result, the collet 10 is expanded in diameter by its own elastic restoring force, and the lock state of the support rod 4 is released.

In the above configuration, as shown in FIG. 2, the rod 4 and the collet 10 are configured as follows.

The outer periphery of the rod 4 is composed of a circular straight outer peripheral surface 40 formed over the entire gripping area A extending in the vertical direction (axial direction).

The inner peripheral surface of the collet 10 is provided at substantially equal intervals in the straight inner peripheral surface 41 force contacting the straight outer peripheral surface 40 in the vertical direction (axial direction). Further, a circumferential groove 42 is provided between the above-mentioned adjacent straight inner peripheral surfaces 41.

[0021] The width dimension w2 force of the circumferential groove 42 is set to a value that is equal to or larger than the width dimension wl of the straight inner circumferential surface 41 and smaller than the diameter d of the ball B. Further, the width dimension wl of the straight inner peripheral surface 41 is set to a value which is not less than half of the width dimension w2 of the circumferential groove 42. Furthermore, before The average thickness force between the minimum value tl and the maximum value t2 of the radial thickness of the tapered outer peripheral surface 11 of the tapered collet 10 is set to a value larger than the diameter d of the ball B.

[0022] Since each dimension is set as described above, when the collet 10 is reduced in diameter via a large number of balls B when the work support 1 is driven to lock, the ball B has an inner circumference of the collet 10. The straight inner peripheral surface 41 can be pressed almost evenly against the straight outer peripheral surface 40 of the rod 4 by preventing the rod from being excessively bent inward in the radial direction. For this reason, it is possible to prevent the surface pressure of the straight inner peripheral surface 41 from becoming excessively high during the lock driving, and to prevent the straight inner peripheral surface 41 from damaging the straight outer peripheral surface 40. As a result, the mouth 4 can be moved smoothly in the axial direction.

The straight inner peripheral surface 41 has a width wl set to a value smaller than the width w2 of the circumferential groove 42, so a large surface pressure can be secured and the force to grip the rod 4 is greatly increased. To increase. In addition, the circumferential groove 42 having a relatively large width can accommodate film-like oil interposed between both the straight inner circumferential surface 41 and the straight outer circumferential surface 40 of the rod 4. Therefore, the friction coefficient between the both surfaces can be increased to further increase the force for gripping the rod 4.

[0023] The inclination angle Θ of the circumferential groove 42 with respect to the straight inner circumferential surface 41 is preferably set to a small value within a range of about 5 degrees to about 10 degrees.

Note that the circumferential groove 42 is not limited to the illustrated triangle, but may have a corner such as a top formed in an arc shape.

The above embodiment can be modified as follows.

In FIG. 2, instead of providing a plurality of straight inner peripheral surfaces 41 at intervals in the axial direction on the inner periphery of the collet 10, circumferential grooves 42 are spirally formed on the inner periphery of the collet 10. Provide. A straight inner peripheral surface 41 that contacts the straight outer peripheral surface 40 of the rod 4 is spirally provided between the spiral peripheral grooves 42. In this modified embodiment, the other configurations are the same as those in the above embodiment, and the same effects as those in the embodiment are achieved.

[0025] The above-described embodiments and modifications can be further modified as follows.

The transmission tool 14 and the piston 24 are separately formed instead of being integrally formed as shown in the figure. It can also be formed on the body. Further, the urging force of the return panel 28 may be applied to the transmission 14 instead of being applied to the piston 24.

The work support 1 can be locked and released by the oil pressure while being locked by the panel force and released by the oil pressure.

As a means for advancing the rod 4 upward, another type of elastic body such as rubber or compressed air may be used instead of the advance panel 5.

The pressure fluid supplied to the working chamber 25 may be a gas such as air instead of a liquid such as pressure oil.

The work support 1 can be installed so that the axis of the rod 4 is in a horizontal direction or an oblique direction, instead of being installed so that the axis of the rod 4 is in a vertical direction.

Claims

The scope of the claims

[1] A taper collet (10) that can be expanded and contracted in the diametrical direction is externally fitted to a rod (4) that is inserted in the housing (2) so as to be movable in the axial direction, and the taper collet (10) The tapered collet (10) is configured to be reduced in diameter by a large number of balls (B) arranged outside the tapered outer peripheral surface (11),

A plurality of straight inner peripheral surfaces (41) that are in contact with the straight outer peripheral surface (40) of the rod (4) are provided on the inner periphery of the taper collet (10) at intervals in the axial direction. A straight groove (42) is provided between the matching straight inner peripheral surfaces (41X41)

The width dimension (w2) of the circumferential groove (42) is set to a value that is equal to or greater than the width dimension (wl) of the straight inner circumferential surface (41) and smaller than the diameter (d) of the ball (B). A work sabot that is characterized by

[2] In the work support of claim 1,

The workpiece support according to claim 1, wherein a width dimension (wl) of the straight inner peripheral surface (41) is set to a value not less than half of a width dimension (w2) of the circumferential groove (42).

[3] A taper collet (10) that can be expanded and reduced in the diametrical direction is externally fitted to a rod (4) that is inserted in the housing (2) so as to be movable in the axial direction, and the taper collet (10) Tapered outer surface (

The taper collet (10) is reduced in diameter by a large number of balls (B) arranged on the outside of 11),

A circumferential groove (42) is provided in a spiral shape on the inner periphery of the taper collet (10), and is in contact with the straight outer peripheral surface (40) of the rod (4) between the spiral circumferential groove (42). Straight inner peripheral surface (41) to be spirally provided,

[4] In the work support of claim 3,

[5] Claims 1 to 4! For any work support! The average value of the minimum value (tl) and the maximum value (t2) of the radial wall thickness of the tapered outer peripheral surface (11) of the tapered collet (10) is the diameter (d) of the ball (B). Work support characterized by being set to a value greater than.