JP2002239886A - Work holding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain well dependent rotation of a work, reduce expenses for a chuck in a previous process and a shorten a rearrangement time. SOLUTION: This work holding device comprises a pasting pan 23 for pasting a work 9, a work holder 16 having an opening portion 16b through which the pasting pan 23 is inserted and a stepped portion 16a near the center of the outer periphery, a permanent magnet 18 fixed to the end of the stepped portion 16a of the work holder 16, a permanent magnet 19 and a permanent magnet 17 fixed to the upper and lower ends of the work holder 16, respectively, a permanent magnet 21 and a permanent magnet 15 opposed to the upper and lower faces of the permanent magnet 18, respectively, in no contact therewith and arranged at the upper and lower parts thereof, respectively, a permanent magnet 20 and a permanent magnet 14 opposed to the outer peripheries of the permanent magnet 19 and the permanent magnet 17, respectively, in no contact therewith and arranged at the outsides thereof, respectively. The respective opposed portions of the permanent magnet 19 and the permanent magnet 20, the permanent magnet 18 and the permanent magnet 15, the permanent magnet 19 and the permanent magnet 20 and the permanent magnet 17 and the permanent magnet 14 have mutually repulsive polarities.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work holding apparatus used in a processing machine for processing a work such as a lens, a mirror or the like made of glass, crystal material, ceramic, or the like, or a molding die.

[0002]

2. Description of the Related Art A work holding device used in a processing machine for processing a work such as an optical element or a mold is disclosed in Japanese Patent Publication No. 7-983.
No. 06 (prior art for all claims). FIG. 8 schematically shows holding of a work according to the above-mentioned conventional technique.

[0003] In FIG. 8, a work 101 is held by a work support 103, and the work support 103 is formed on a work shaft support 104 by a U-shaped upper arm 10.
2 is rotatably supported. Upper arm 102
Is a swing arm 10 formed in a U-shape.
5 is rotatably connected to the swing arm support portion 1 via an upper arm support portion 106.
07, it is rotatably connected to the stay 108. Then, the axis of the rotation center of the swing arm 105 is X,
When the axis of the center of rotation of the upper arm 102 is Y and the axis of the center of rotation of the workpiece support 103 is Z, the axes X, Y, and Z are set to intersect at one point O.

FIG. 9 shows a configuration example of a work holding device that embodies the above principle. A sticking plate 113 as a work supporting portion 103 to which the work 101 is stuck is a bearing 110.
8 (corresponding to the work shaft support 104 in FIG. 8), the upper arm 102 is rotatably held around the axis Z. The outer ring of the bearing 110 is fixed to the upper arm 102 by a stopper 111 and a screw 109. Also, the upper arm 102 is
The swing arm 105 is configured to be rotatable around the axis Y via the swing arm 2 via the rotation arm 2.

[0005]

The processing of the work by the work holding device having the above-mentioned structure is performed as shown in FIG. The tool 114 is brought into contact with the processing surface 101a of the workpiece 101 held on the sticking plate 113,
4 is swung in the α direction, or the work 101 is swung back and forth in the β direction so that the work 101 and the tool 11
The tool 114 is caused to rotate (gamma direction) while relatively oscillating with the tool 4. At this time, the work 101 is rotated in the same direction by the rotational movement of the tool 114 (hereinafter, this rotation is referred to as a subordinate rotation), whereby the processing surface 101a of the work 101 is processed.

However, at this time, if there is no subordinate rotational movement of the work 101, the outer peripheral portion of the tool 114 has a higher peripheral speed than the inner peripheral portion, so that the tool 114 wears more than the inner peripheral portion due to friction with the work 101. This promotes uneven wear of the tool 114.
As a result, the shape of the workpiece 101 processed by the unevenly worn tool 114 is also lost. Therefore, the work 101
In order to perform stable machining, it is important to rotate the work 101 dependently on the tool 114 to prevent uneven wear of the tool 114.

[0007] The work 101 rotates dependently when the rotational force of the tool 114 is transmitted to the work 101 as a rotational force due to friction between the work 101 and the tool 114. As a factor that reduces the transmission of the rotational force, there is a problem of the bearing 110 that holds the sticking plate 113 rotatably. That is, when the starting torque of the bearing 110 is larger than the friction torque between the workpiece 101 and the tool 114,
Dependent rotation is not possible. Also, even if the starting torque is small enough at the beginning, the coolant is
When the coolant enters the interior of the bearing 10 and the chips mixed with the coolant damage the inner and outer races and the ball of the bearing 110, the starting torque increases, and the subordinate rotation becomes impossible.

In the prior art work holding apparatus, when the revolving diameter of the ball of the bearing 110 is large, the starting torque is large and does not follow the rotation. However, in order to reduce the starting torque of the bearing 110, the revolving diameter of the ball of the bearing 110 is reduced. In this case, the damage caused by the chips is increased, and the subordinate rotation is impossible. In addition, since a processing load is applied to the bearing 110, the working life is shorter than the original life. As described above, in the related art, there is a problem that stable machining cannot be performed because good subordinate rotation of the work cannot be maintained.

When the workpiece 101 is pasted on the pasting plate 113 and precision grinding and polishing are performed, as a pre-process, as shown in FIG. The cup-type grinding tool 120 is held by a chuck 122 attached to the
By rotating and moving back and forth,
Performs rough grinding (curve generator method).

As described above, according to the prior art, it is not possible to maintain a good subordinate rotation of the work 101,
In order to at least slightly improve the subordinate rotation of the work 101, it is necessary to set the size of the bearing 110 with respect to the diameter of the work 101. As a result, each work 1
It is necessary to change the outer diameter of the sticking plate 113 with respect to 01. For this reason, in the above-described rough grinding, which is the previous step, the chuck 122 for holding the sticking plate 113 is prepared in accordance with the work 101, and the chuck 122
However, there is a problem in that the cost is high and the changeover takes time.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the related art, and it is an object of the present invention to maintain a good subordinate rotation of a work, reduce the cost of a chuck in a previous process, and shorten a setup change time. An object of the present invention is to provide a work holding device that can perform the work.

[0012]

According to a first aspect of the present invention, there is provided a work holding apparatus comprising: a stay fixed to a pressing mechanism of a processing machine; and a first support attached to the stay. A swing arm, which is rotatably supported via a shaft and has a U-shape having a first support shaft as a symmetrical axis, and a second intersecting first support shaft at both ends of the swing arm. An upper arm having a U-shape that is rotatably supported via a support shaft, and a third support shaft that is orthogonal to the second support shaft and rotatably held at the center of the upper arm. A work holder, comprising: a sticking plate for sticking a work, an opening for inserting the sticking plate, and a stepped portion near the center of the outer periphery; A first magnet fixed to the tip of the stepped portion of the holder; Second and third magnets fixed to the outer periphery of the upper end and the lower end of the work holder, respectively, are disposed at the upper and lower portions, respectively, facing the upper and lower surfaces of the first magnet in a non-contact manner. A fourth and a fifth magnet, and a sixth and a seventh magnet arranged on the outside of the second and the third magnet in a non-contact manner facing the outer periphery of each of the second and the third magnets, and Opposing portions of the magnet and the fourth magnet, the first magnet and the fifth magnet, the second magnet and the sixth magnet, and the third magnet and the seventh magnet, respectively, Are characterized by having polarities repelling each other.

According to a second aspect of the present invention, there is provided a workpiece holding device, comprising: a stay fixed to a pressurizing mechanism of a processing machine; and a rotatably supported by the stay via a first support shaft. A swing arm having a U-shape having a support shaft as a symmetric axis, and a pivot arm supported at both ends of the swing arm via a second support shaft intersecting the first support shaft. A work holding device having an upper arm having a U-shape and a work holder rotatably held at a center of the upper arm by a third support shaft orthogonal to the second support shaft, the work being attached to the upper arm. A sticking dish to be attached, a work holder having an opening for inserting the sticking dish, and having a stepped portion near the center of the outer periphery, respectively fixed to the upper surface and the lower surface of the stepped portion of the work holder, An inclined surface inclined with respect to the third support shaft First and second magnets having,
A third and a fourth magnet having an inclined surface facing the inclined surface of each of the first and second magnets in a non-contact manner, wherein the first magnet and the third magnet, The opposite inclined surfaces of the second magnet and the fourth magnet have polarities repelling each other.

According to a third aspect of the present invention, there is provided a workpiece holding device according to the first or second aspect, wherein a fluid is supplied to an upper end of the work holder.

According to a fourth aspect of the present invention, there is provided a workpiece holding device according to the first or second aspect, wherein an upper end of the work holder and the upper arm or a member fixed to the upper arm are provided. It is characterized by having a pivot bearing.

According to a fifth aspect of the present invention, there is provided a workpiece holding apparatus according to the first aspect, wherein at least the fourth magnet is constituted by an electromagnet.

According to a sixth aspect of the present invention, there is provided a workpiece holding apparatus according to the second aspect, wherein at least one of the first magnet and the third magnet is constituted by an electromagnet.

That is, in the work holding device according to the first aspect, the sticking plate for sticking the work is inserted into the opening of the work holder. The work is brought into contact with the grindstone by the pressing mechanism of the processing machine, and the work is ground or polished by rotating the grindstone and relatively swinging the work and the grindstone.

At this time, the rotational force of the grindstone is transmitted to the work, so that a force is applied to the sticking plate in the radial direction through the work, but the outer periphery of the upper end portion and the lower end portion of the work holder holding the sticking plate. The second and third grindstones fixed to each other and the sixth and seventh magnets, which are arranged on the outer sides of the second and third magnets facing each other in a non-contact manner, repel each other, The work holder can maintain the position where it rotates about the work rotation center axis (axis Z).

When a thrust direction force is applied to the sticking plate via the work by the pressurizing mechanism of the processing machine, the first magnet fixed to the tip of the stepped portion of the work holder,
The fourth magnet arranged in an upper part in a non-contact manner with the upper surface of the magnet
Although the gap between the first magnet and the fourth magnet is reduced, the repulsive force between the first magnet and the fourth magnet is increased as the gap is reduced, so that they do not come into contact with each other.

As described above, since the work holder is rotatably held at the center of the upper arm, there is nothing to suppress the subordinate rotation of the work with respect to the grindstone, and the work is properly subordinately rotated.

In the work holding device according to the second aspect, the sticking plate on which the work is stuck is inserted into the opening of the work holder. The work is brought into contact with the grindstone by the pressing mechanism of the processing machine, and the work is ground or polished by rotating the grindstone and relatively swinging the work and the grindstone.

At this time, the rotational force of the grindstone is transmitted to the work, so that a radial force is applied to the sticking plate via the work, but the upper and lower surfaces of the stepped portion of the work holder holding the sticking plate are held. The first and second magnets are respectively fixed and inclined surfaces inclined with respect to the third support shaft,
The third and fourth magnets, each having an inclined surface facing the inclined surface of the first and second magnets in a non-contact manner, repel each other, and the work holder rotates by the radial component of the repulsive force. The position of rotation about the central axis (axis Z) can be maintained.

When a force is applied to the sticking plate in the thrust direction via the work by the pressurizing mechanism of the processing machine, the gap between the first magnet and the third magnet is narrowed. 3
Since the thrust component of the repulsive force between the magnets and the magnets increases, they do not come into contact with each other.

As described above, since the work holder is rotatably held at the center of the upper arm, there is nothing to suppress the dependent rotation of the work with respect to the magnet, and the work is favorably rotated dependently.

According to a third aspect of the present invention, in the work holding apparatus according to the first or second aspect,
At the time of pressurizing the work by the pressurizing mechanism of the processing machine, the work holder is pressurized from above by supplying a fluid such as air to the upper end of the work holder to cancel the pressing force by the pressurizing mechanism of the processing machine. Other operations are the same as those of the first or second aspect.

According to a fourth aspect of the present invention, there is provided the work holding device according to the first or second aspect.
A pivot bearing is provided between the upper end of the work holder and the upper arm or a member fixed to the upper arm, and when the work is pressed by the pressing mechanism of the processing machine, the pressing force of the pressing mechanism of the processing machine is pivoted. Receive with bearings.
Other operations are the same as those of the first or second aspect.

According to a fifth aspect of the present invention, in the work holding apparatus of the first aspect, at least the fourth magnet is constituted by an electromagnet whose magnetic force can be controlled,
When the work is pressed by the pressing mechanism of the processing machine, the pressing force of the pressing mechanism of the processing machine is canceled by increasing the magnetic force. Other operations are the same as those of the first aspect.

According to a sixth aspect of the present invention, in the work holding apparatus according to the second aspect, at least one of the first magnet and the third magnet is constituted by an electromagnet whose magnetic force can be controlled. When the work is pressed by the pressing mechanism of the processing machine, the magnetic force is increased to cancel the pressing force by the pressing mechanism of the processing machine. Other operations are the same as those of the second aspect.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the work holding apparatus of the present invention will be described below with reference to the drawings. Note that, in each embodiment, the same elements are assigned the same reference numerals and corresponded.

(Embodiment 1) An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a front view showing the work holding device partially cut away, and FIG. 2 is a side view showing the work holding device partially cut away. In this embodiment, the first to seventh magnets correspond to claim 1.

The stay 2 is fixed by screws 3 to a work shaft 1 having a pressing mechanism (not shown) of the processing machine body. At the lower end 2 a of the stay 2, a U-shaped swing arm 4 is supported by a nut 8 via a support shaft 5, a washer 6, and a bearing 7 on an axis X orthogonal to a workpiece rotation center axis (axis Z). It is rotatably connected. The U-shaped swing arm 4 has an opening having the support shaft 5 as a symmetric axis, and the swing arm 4 is provided at both ends of the opening of the swing arm 4.
An upper arm 10 having a U-shape similar to that of FIG.
And is rotatably connected on an axis Y orthogonal to the axis X and intersecting the work rotation center axis (axis Z).
The pins 12 are fixed to both side surfaces of the swing arm 4 with screws 13. In the center of the upper arm 10, a through hole 10 centered on the workpiece rotation center axis (axis Z) is provided.
a, a counterbore hole 10b and a counterbore hole 10c are provided in a circular shape, the counterbore hole 10b is provided above the through hole 10a, and the counterbore hole 10c is provided above the counterbore hole 10b.

A ring-shaped permanent magnet 14 as a seventh magnet having a polarity in the radial direction is fixed to the lower end of the inner periphery of the through hole 10a of the upper arm 10 about the work rotation center axis (axis Z). And a fifth surface having a polarity in the thrust direction is formed on the upper surface of the counterbore hole 10b.
A ring-shaped permanent magnet 15 as a magnet is fixed.

A cylindrical work holder 16 is provided in the through hole 10a of the upper arm 10 with the work rotation center axis (Z axis) as the center. At the lower end of the outer periphery of the work holder 16, a permanent magnet 17 is fixed as a third magnet facing the permanent magnet 14 and having a polarity in the radial direction. In the vicinity of the center of the work holder 16, there is provided a stepped portion 16a extending to the upper surface of the counterbore hole 10b.
A ring-shaped permanent magnet 18 as a first magnet having a polarity in the thrust direction facing the permanent magnet 15 is fixed to a tip of the permanent magnet 15. Opposing poles of the permanent magnet 14 and the permanent magnet 17 and of the permanent magnet 15 and the permanent magnet 18 are magnetized so as to have repelling polarities. Further, a ring-shaped permanent magnet 19 as a second magnet having a polarity in a radial direction about a work rotation center axis (axis Z) is fixed to the upper end of the outer periphery of the work holder 16.

The counterbore 10c of the upper arm 10
In order not to interfere with the upper part of the work holder 16,
A cover 22 having a circular counterbore 22a around the workpiece rotation center axis (axis Z) is provided. The cover 22 has a lower surface on the outer peripheral side thereof placed on the upper surface of the counterbore 10c and a screw 25. Is fixed to the upper arm 10.

On the cover 22, a ring-shaped permanent magnet 20 as a sixth magnet having a polarity in the radial direction about the center axis of rotation (axis Z) of the work is fixed to the upper end of the work holder 16. Is fixed at a position facing the permanent magnet 19. A ring-shaped permanent magnet 21 as a fourth magnet having a polarity in the thrust direction is fixed to the cover 22 at an upper position facing the permanent magnet 18 fixed to the stepped portion 16 a of the work holder 16. Have been. Opposing poles of the permanent magnet 20 and the permanent magnet 19 and of the permanent magnet 21 and the permanent magnet 18 are magnetized to have repelling polarities.

Accordingly, the work holder 16 is provided with a radial repulsive force between the permanent magnet 17 and the permanent magnet 14 and between the permanent magnet 19 and the permanent magnet 20, and between the permanent magnet 18 and the permanent magnet 21 and between the permanent magnet 18 and the permanent magnet. Due to the repulsion force in the thrust direction between the upper arm 15 and the upper arm 10, the workpiece is rotatably held in a non-contact manner about the work rotation center axis (axis Z).

The work holder 16 is provided with an opening 16b having a bottom from below with respect to the center axis of rotation of the work (axis Z). The workpiece 9 is held in such a manner that it is inserted into the portion 16b and the processing surface 9a of the work 9 faces downward. The sticking tray 23 is made of a magnetic material, and is attracted and held by the magnetic force of the permanent magnet 24 disposed at the upper end (bottom) of the opening 16 b of the work holder 16. Work 9
Is a lens made of glass, crystal material, ceramic, etc.
It consists of an optical element such as a mirror or a molding die.

The work 9 is processed by a grindstone 27 disposed below the work 9. That is, the processing surface 9a of the work 9 is brought into contact with a grindstone 27 fixed to a grindstone shaft portion 26 that rotates and swings, and the grinding and polishing of the work 9 are performed while supplying a grinding liquid or a polishing liquid to this contact portion. Polishing is performed.

In the above-described configuration, the intersection O between the axis X and the axis Z is set so that the rotating grindstone 27 opposes the tangential force acting on the processing surface 9a of the workpiece 9 so that the workpiece has a convex spherical shape. 9 is located at a position that coincides with or is close to the intersection of the tangent plane and the axis Z at the outermost periphery (point P) of the machining surface 9a.

Next, the operation of the work holding device having the above configuration will be described. In precision grinding and polishing with a polishing machine,
The attachment plate 23 on which the work 9 is attached is placed on the work holder 16.
Into the opening 16b. At this time, the sticking plate 23, which is a magnetic material, is attracted and held by the permanent magnet 24 fixed to the upper end of the opening 16b.

The work surface 9a of the work 9 is brought into contact with the grindstone 27 by a pressurizing mechanism of the work shaft 1 not shown, and a grinding liquid or a polishing liquid is supplied to the contact part from a nozzle not shown. . The work 9 is ground or polished by rotating and oscillating the grindstone 27.

At this time, the rotational force of the grindstone 27 is transmitted to the work 9, whereby a force is applied to the sticking plate 23 in the radial direction via the work 9, but the permanent magnet 17 fixed to the work holder 16 and A permanent magnet 19 and a permanent magnet 1 disposed on the upper arm 1 to face each other.
The gap between the work holder 16 and the through-hole 10a of the upper arm 10 and the gap between the work holder 16 and the counterbore hole 22a of the cover 22 are kept constant by the repulsive force of the work holder 16 and the permanent magnet 20. Can be maintained at a position where it rotates about the work rotation center axis (axis Z).

When the work 9 is brought into contact with the grindstone 27 by the pressurizing mechanism of the work shaft 1, a reaction is applied upwardly to the sticking plate 23 via the work 9 in the thrust direction. Work holder 16 holding
A permanent magnet 18 fixed to the tip of the stepped portion 16a,
The gap between the permanent magnet 21 and the permanent magnet 21 disposed on the cover 22 is narrowed, but the magnetic force is inversely proportional to the square of the distance. Therefore, the repulsive force between the permanent magnet 18 and the permanent magnet 21 rapidly increases, The stepped portion 16a of the work holder 16 does not contact the lower surface of the cover 22.

Therefore, since the work holder 16 is rotatably held without contact with the upper arm 10 and the cover 22, there is nothing to suppress the dependent rotation of the work 9 with respect to the grindstone 27, and a good dependent rotation is obtained. .

According to the present embodiment, the work holder 1
Since the work 9 and the sticking plate 23 are held by the upper arm 10 in a non-contact manner without the intervention of a bearing in the state of being held by 6, the good rotation of the work 9 can be maintained. Further, since there is almost no starting torque as compared with the bearing, the work holder 16 is not provided as in the prior art.
It is not necessary to change the diameter of the insertion portion of the sticking plate 23 in accordance with the diameter of the work 9, so that the cost of the chuck in the rough grinding processing in the previous process can be reduced, and the setup change time can be shortened.

(Embodiment 2) An embodiment of the present invention will be described with reference to FIGS. 3, 4, and 5. FIG. 3 is a front view showing the work holding device partially cut away, FIG. 4 is a side view showing the work holding device partially cut away, and FIG. 5 is a partially cutaway work holding device according to a modification of the present embodiment. FIG.

The work holder 16 of the present embodiment is provided with an upper end portion 16c extending from the work holder 16 of the first embodiment above a permanent magnet 19 as a second magnet. On the other hand, the cover 22 is
6, and a counterbore hole 22 b is provided inside the extended portion of the cover 22 so as to have a gap with the outer periphery of the upper end 16 c of the work holder 16. A joint 31 communicating with the counterbore hole 22b is fixed to the upper surface of the cover 22, and a joint 32 is
Has been fixed. The joints 31 and 32 are tubes 33
The other end of the joint 32 is connected to a fluid supply device (not shown). Other configurations are the same as those of the first embodiment, and therefore, the same components are denoted by the same reference symbols and description thereof will be omitted.

Next, the operation of the work holding device having the above configuration will be described. In precision grinding and polishing with a polishing machine,
The attachment plate 23 on which the work 9 is attached is placed on the work holder 16.
Into the opening 16b. At this time, the sticking plate 23, which is a magnetic material, is attracted and held by the permanent magnet 24 fixed to the upper end of the opening 16b.

The processing surface 9a of the work 9 is brought into contact with the grindstone 27 by the pressurizing mechanism of the work shaft 1 not shown, and a grinding liquid or a polishing liquid is supplied to the contact part from a nozzle not shown. . The work 9 is ground or polished by rotating and oscillating the grindstone 27.

At this time, when the rotational force of the grindstone 27 is transmitted to the work 9, a force is applied to the sticking plate 23 in the radial direction via the work 9, but the third magnet fixed to the work holder 16 is applied. Permanent magnet 17 as the second
Of the work holder 16 and the upper arm 10 due to the repulsive force of the permanent magnets 19 as the magnets and the seventh permanent magnet 14 and the sixth permanent magnet 20 disposed on the upper arm 10 to face each other. A gap between the holes 10a,
And counterbore hole 22 of work holder 16 and cover 22
The gap with respect to a is kept constant, and the work holder 16 can be maintained at a position where the work holder 16 rotates around the work rotation center axis (axis Z).

When the work 9 is brought into contact with the grindstone 27 by the pressurizing mechanism of the work shaft 1, the reaction exerts an upward force on the sticking plate 23 through the work 9 in the thrust direction. The counterbore hole 22b of the cover 22 and the work holder 16 are connected to the shaft unit 1 via a joint 32, a tube 33, and a joint 31 by a fluid supply device (not shown).
The air is supplied to the space between the upper end 16c and the upper end. The air supply pressure at this time is made equal to the pressing force of the pressing mechanism (not shown) of the work shaft 1. Thereby, the gap between the upper surface of the stepped portion 16a of the work holder 16 and the lower surface of the cover 22 and the stepped portion 1 of the work holder 16
The gap between the lower surface of 6a and the upper surface of the counterbore 10b of the upper arm 10 is kept constant, and the work holder 16 is rotatably held in non-contact with the upper arm 10 and the cover 22. There is nothing to suppress the subordinate rotation with respect to, and good subordinate rotation can be maintained.

According to the present embodiment, the same effects as those of the first embodiment can be obtained, and the permanent magnets 15 and 18 can be canceled by canceling the pressing force of the pressing mechanism of the work shaft 1 by the air supply pressure. , 21 can be applied irrespective of the magnetic force, so that the subordinate rotation of the work 9 can be favorably maintained even in high-load grinding and polishing.

In the present embodiment, the air is supplied by the fluid supply device (not shown) of the work shaft portion 1.
The same effect can be obtained by supplying a fluid such as a grinding fluid, a polishing fluid, or water instead of air.

Further, as a modification of the present embodiment, as shown in FIG. 5, instead of a fluid supply device, joints 31, 32, and tube 33, not shown, of the work shaft 1, a counterbore hole 22b of the cover 22 is provided. Between the lower surface of the work holder 16 and the upper surface of the upper end portion 16c of the work holder 16, a pivot bearing 34 composed of a ball and a pair of retainers for receiving the ball is provided.
Accordingly, the pressurizing mechanism (not shown) of the work shaft portion 1 is pressed by the pivot bearing 34, and the starting torque of the pivot bearing 34 is smaller than that of a normal radial bearing. Dependent rotation can be maintained.

(Embodiment 3) Embodiment 3 of the present invention will be described with reference to FIG. FIG. 6 is a partially cutaway front view of the work holding device.

In this embodiment, the permanent magnet 21 as the fourth magnet in the first embodiment is eliminated, and a ring-shaped electromagnet 35 as the fourth magnet is provided instead of the permanent magnet 21. ing. A connection cord 36 connected to a control device (not shown) is connected to the electromagnet 35, so that the magnetic force of the electromagnet 35 can be controlled by the control device. Other configurations are the same as those of the first embodiment, and therefore, the same components are denoted by the same reference symbols and description thereof will be omitted.

Next, the operation of the work holding device having the above configuration will be described. In precision grinding and polishing with a polishing machine,
The attachment plate 23 on which the work 9 is attached is placed on the work holder 16.
Into the opening 16b. At this time, the sticking plate 23, which is a magnetic material, is attracted and held by the permanent magnet 24 fixed to the upper end of the opening 16b.

The processing surface 9a of the work 9 is brought into contact with the grindstone 27 by a pressurizing mechanism of the work shaft 1 not shown, and a grinding liquid or a polishing liquid is supplied to the contact part from a nozzle not shown. . The work 9 is ground or polished by rotating and oscillating the grindstone 27.

At this time, when the rotational force of the grindstone 27 is transmitted to the work 9, a force is applied to the sticking plate 23 in the radial direction via the work 9, but the third magnet fixed to the work holder 16 is applied. Permanent magnet 17 as the second
The permanent magnets 19 as the magnets, and the permanent magnet 14 as the seventh magnet and the permanent magnet 20 as the sixth magnet disposed opposite to each other on the upper arm 10 repel each other. 16 and the gap between the through hole 10a of the upper arm 10 and the work holder 16
The gap between the cover 22 and the counterbore hole 22a of the cover 22 is kept constant, and the work holder 16 is fixed to the work rotation center axis (axis Z).
Can be maintained at a position rotated around the center.

When the work 9 is brought into contact with the grindstone 27 by the pressurizing mechanism of the work shaft 1, when the sticking plate 23 is subjected to an upward force in the thrust direction via the work 9 due to the reaction. At the same time, the repulsive force between the electromagnet 35 and the permanent magnet 18 as the first magnet causes the upper arm 1
A control device (not shown) controls the repulsive force between the permanent magnet 15 and the permanent magnet 18 serving as the fifth magnet fixed to the upper surface of the counterbore hole 10b to be equal to the resultant force of the pressure by the pressing mechanism. A magnetic force is applied to the electromagnet 35. Thereby, the gap between the upper surface of the stepped portion 16a of the work holder 16 and the lower surface of the cover 22, and the lower surface of the stepped portion 16a of the work holder 16 and the counterbore hole 1 of the upper arm 10 are formed.
0b is maintained constant, and the work holder 16 is rotatably held in non-contact with the upper arm 10 and the cover 22, so that there is nothing to suppress the subordinate rotation of the work 9 with respect to the grindstone 27. Dependent rotation can be maintained.

According to the present embodiment, the same effect as that of the first embodiment can be obtained, and the pressing force of the pressing mechanism of the work shaft portion 1 is canceled with a simple configuration in which the magnetic force of the electromagnet 35 is changed. As a result, the permanent magnet 15,
Pressure can be applied irrespective of the magnetic force of 18, so that the subordinate rotation of the work 9 can be favorably maintained even in high-load grinding and polishing.

(Embodiment 4) Embodiment 4 of the present invention will be described with reference to FIG. FIG. 7 is a partially cutaway front view of the work holding device. In this embodiment, the first to fourth magnets correspond to claim 2.

In the present embodiment, the shape of the work 9 in the first embodiment is changed from a convex spherical shape to a concave spherical shape. The intersection point O is arranged so as to coincide with or be close to the intersection point O between the tangent plane at the outermost peripheral point P of the work surface 9a of the workpiece 9 and the axis Z. In the present embodiment, the permanent magnets 14, 15, 1 in the first embodiment are used.
7, 18, 19, 20, and 21 were abolished and configured as follows.

A ring-shaped permanent magnet 37 as a first magnet and a ring-shaped permanent magnet 38 as a second magnet are fixed to the upper and lower surfaces of the stepped portion 16a of the work holder 16. The permanent magnet 37 and the permanent magnet 38 have an inclined surface 37a and an inclined surface 38a. Further, a ring-shaped permanent magnet 39 as a third magnet having an inclined surface 39a opposed to the inclined surface 37a of the permanent magnet 37 and the inclined surface 38a of the permanent magnet 38, and a fourth magnet having an inclined surface 40a as a third magnet. A ring-shaped permanent magnet 40 is provided above the counterbore hole 22 b of the cover 22 and on the upper surface of the counterbore hole 10 b of the upper arm 10. The inclined surface 37a of the permanent magnet 37 and the inclined surface 39a of the permanent magnet 39 are opposed with a gap, and the inclined surface 38a of the permanent magnet 38 and the inclined surface 40a of the permanent magnet 40 are opposed with a gap. The permanent magnets 37 and 39 and the permanent magnets 38 and 40 have polarities that repel each other. Further, the upper portion of the cover 22 has an opening 22 so as not to interfere with the work holder 16.
c is provided. Other configurations are the same as those of the first embodiment, and therefore, the same components are denoted by the same reference symbols and description thereof will be omitted.

Next, the operation of the work holding device having the above configuration will be described. In precision grinding and polishing with a polishing machine,
The attachment plate 23 on which the work 9 is attached is placed on the work holder 16.
Into the opening 16b. At this time, the sticking plate 23, which is a magnetic material, is attracted and held by the permanent magnet 24 fixed to the upper end of the opening 16b.

The processing surface 9a of the work 9 is brought into contact with the grindstone 27 by a pressurizing mechanism of the work shaft 1 not shown, and a grinding liquid or a polishing liquid is supplied to the contact part from a nozzle not shown. . The work 9 is ground or polished by rotating and oscillating the grindstone 27.

At this time, the rotational force of the grindstone 27 is transmitted to the sticking plate 23 via the work 9 to the work 9, so that a force is applied in the radial direction.
The permanent magnet 37 and the permanent magnet 38 fixed to the cover 22 and the permanent magnet 39 and the permanent magnet 40 disposed on the cover 22 facing each other repel each other between the facing inclined surfaces. Then, the component force of the repulsive force acts in the radial direction and the thrust direction, respectively. Thereby, the gap between the work holder 16 and the upper arm 10,
In addition, the gap between the work holder 16 and the cover 22 is kept constant, and the work holder 16 can be maintained at a position where the work holder 16 rotates about the work rotation center axis (axis Z).
Since the workpiece 9 is rotatably held in a non-contact manner, there is nothing to suppress the subordinate rotation of the work 9 with respect to the grindstone 27, and a favorable subordinate rotation can be maintained.

According to the present embodiment, the permanent magnets 37, 3
8, 39 and 40 have inclined surfaces 37a, 38a and 39, respectively.
a, 40a, and a structure in which inclined surfaces having repelling polarities are opposed to each other to repel each other can be provided with a structure in which the number of permanent magnets is reduced. 9 can be favorably maintained.

The technical idea having the following configuration is derived from the above specific embodiment. (Supplementary note) (1) A stay fixed to a pressurizing mechanism of a processing machine, and a U-shape that is rotatably supported by the stay via a first support shaft and has a first support shaft as a symmetric axis. A swing arm having a shape;
A U-shaped upper arm rotatably supported via a second support shaft intersecting a first support shaft at both ends of the swing arm, and a second
A work holder rotatably held by a third support shaft orthogonal to the support shaft of the work support device, the work support device having an attachment plate for attaching a work, and an opening for inserting the attachment plate. A work holder having a stepped portion near the center of the outer periphery, a first magnet fixed to the tip of the stepped portion of the work holder, and a first magnet fixed to the outer periphery of an upper end and a lower end of the work holder. The second and third magnets are disposed on the work holder holding portion of the upper arm in a non-contact manner with the upper and lower surfaces of the first magnet in a non-contact manner, and are disposed on upper and lower portions of the upper and lower surfaces. The fourth and fifth magnets respectively disposed are disposed on the work holder holding portion of the upper arm in a non-contact manner with the outer circumferences of the second and third magnets, respectively. Comprising a serial sixth and seventh magnets arranged outside of the second and third magnets, wherein the first magnet and the fourth magnet, wherein the first magnet 5
The magnets, the second magnet and the sixth magnet, and the opposing portions of the third magnet and the seventh magnet have polarities repelling each other. apparatus.

(2) A stay fixed to the pressurizing mechanism of the processing machine, and a U-shape which is rotatably supported by the stay via a first support shaft and has the first support shaft as a symmetric axis. A swing arm having a U-shape which is rotatably supported at both ends of the swing arm via a second support shaft intersecting a first support shaft; and In a work holding device having a work holder rotatably held on a third support shaft orthogonal to the second support shaft at the center of the upper arm, a sticking plate for sticking a work and the sticking plate are inserted. And a work holder having a stepped portion in the vicinity of the center of the outer periphery and fixed to upper and lower surfaces of the stepped portion of the work holder, respectively, and inclined with respect to the third support shaft. First and second magnets with inclined surfaces A third and a fourth magnet having an inclined surface facing the inclined surface of each of the first and second magnets in a non-contact manner, and disposed on the work holder holding portion of the upper arm; The work holding device, wherein the first and third magnets, and the inclined surfaces of the second and fourth magnets, which have opposite polarities, have opposite polarities.

According to the work holding device described in the appendix (1), the work and the sticking plate are held in a non-contact manner without the intervention of the bearing, so that a starting torque is hardly required and a good subordinate rotation can be maintained. it can. Also, there is almost no starting torque compared to bearings, and it is not necessary to change the diameter of the sticking plate inserted into the work holder according to the diameter of the work.
The setup change time can be reduced.

According to the work holding device of the supplementary item (2), the same effects as those of the first aspect can be obtained, and the subordinate rotation of the work can be maintained in a good state even with a structure in which the number of permanent magnets is reduced. .

[0074]

As described above, according to the first aspect of the present invention,
According to the work holding device according to the first aspect, the work and the sticking plate are held in a non-contact manner without the intervention of a bearing. Therefore, a starting torque is hardly required, and a good subordinate rotation can be maintained. In addition, there is almost no starting torque compared to bearings, and there is no need to change the diameter of the sticking plate inserted into the work holder according to the diameter of the work. Can be shortened.

According to the workpiece holding device of the second aspect of the present invention, the same effects as those of the first aspect are exhibited, and the subordinate rotation of the workpiece is maintained in a good state even with a structure in which the number of permanent magnets is reduced. be able to.

According to the workpiece holding device of the third aspect of the present invention, the same effects as those of the first or second aspect can be obtained, and by supplying the fluid to the upper end of the work holder, regardless of the magnetic force of the permanent magnet. Since the work shaft can be pressurized by the pressurizing mechanism, the subordinate rotation of the work can be favorably maintained even in high-load grinding and polishing.

According to the workpiece holding device of the fourth aspect of the present invention, the same effects as those of the first or second aspect can be obtained, and by providing the pivot bearing between the upper end of the work holder and the upper arm, etc. The work shaft can be pressurized by the pressurizing mechanism regardless of the magnetic force of the magnet, so that the subordinate rotation of the work can be favorably maintained even in high-load grinding and polishing.

According to the workpiece holding device of the fifth aspect of the present invention, the same effect as that of the first aspect is obtained, and the magnetic force of the electromagnet is adjusted so that the work shaft can be pressurized by the pressurizing mechanism. Since a repulsive force can be generated between the magnets, the subordinate rotation of the work can be favorably maintained even in high-load grinding and polishing.

According to the work holding device of the sixth aspect of the present invention, the same effect as that of the second aspect is obtained, and the magnetic force of the electromagnet is adjusted so that the work shaft can be pressurized by the pressurizing mechanism. Since a repulsive force can be generated between the magnets, the subordinate rotation of the work can be favorably maintained even in high-load grinding and polishing.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view of Embodiment 1 of the present invention.

FIG. 2 is a side view showing the first embodiment of the present invention, partially cut away.

FIG. 3 is a front view showing a second embodiment of the present invention, partially cut away;

FIG. 4 is a side view showing a second embodiment of the present invention, partially cut away.

FIG. 5 is a partially cutaway front view showing a modification of the second embodiment of the present invention.

FIG. 6 is a front view showing a third embodiment of the present invention, partially cut away;

FIG. 7 is a front view showing a fourth embodiment of the present invention, partially cut away;

FIG. 8 is a diagram schematically showing a conventional technique.

FIG. 9 is a half sectional front view showing a conventional technique.

FIG. 10 is a sectional view showing a conventional technique.

FIG. 11 is a front view showing the prior art with a part cut away.

[Explanation of symbols]

Reference Signs List 1 work shaft portion 2 stay 4 swing arm 5 support shaft 9 work 10 upper arm 10a through hole 12 pin 14, 15, 17, 18, 19, 20, 21, 24 permanent magnet permanent magnet 16 work holder 22 cover 22a counterbore hole 22b Counterbore hole 22c Opening 23 Pasting plate 35 Electromagnet 37, 38, 39, 40 Permanent magnetic permanent stone 37a, 38a, 39a, 40 Inclined surface

Claims (6)

[Claims] A stay fixed to a pressurizing mechanism of a processing machine; a stay rotatably supported by the stay via a first support shaft;
A swing arm having a U-shape having a first support axis as a symmetric axis, and rotatably supported at both ends of the swing arm via a second support shaft intersecting the first support shaft. A work holding device comprising: an upper arm having a U-shape; and a work holder rotatably held on a third support shaft orthogonal to the second support shaft at the center of the upper arm. A sticking plate for attaching the work, a work holder having an opening for inserting the sticking plate, and having a stepped portion near the center of the outer periphery; and a work holder fixed to a tip of the stepped portion of the work holder. First
And second and third magnets respectively fixed to the outer periphery of the upper end and the lower end of the work holder, facing the upper and lower surfaces of the first magnet in a non-contact manner,
Fourth and fifth magnets respectively disposed on the upper and lower parts, and sixth and seventh magnets disposed on the outside in a non-contact manner opposed to the outer periphery of each of the second and third magnets, The first magnet and the fourth magnet, the first magnet and the fifth magnet, the second magnet and the sixth magnet, and the third magnet and the seventh magnet. The workpiece holding device, wherein opposing portions of the magnets have polarities repelling each other. A stay fixed to a pressurizing mechanism of the processing machine; and a rotatably supported by the stay via a first support shaft;
A swing arm having a U-shape having a first support axis as a symmetric axis, and rotatably supported at both ends of the swing arm via a second support shaft intersecting the first support shaft. A work holding device comprising: an upper arm having a U-shape; and a work holder rotatably held on a third support shaft orthogonal to the second support shaft at the center of the upper arm. A sticking plate for attaching a work, a work holder having an opening for inserting the sticking plate, and having a stepped portion in the vicinity of the center of the outer periphery; and an upper surface and a lower surface of the stepped portion of the work holder, respectively. First and second magnets fixed and having inclined surfaces inclined with respect to the third support shaft, and inclined surfaces opposed to the inclined surfaces of the first and second magnets in a non-contact manner. And third and fourth magnets, The work holding device, wherein the first and third magnets, and the inclined surfaces of the second and fourth magnets, which have opposite polarities, have opposite polarities. 3. The work holding device according to claim 1, wherein a fluid is supplied to an upper end of the work holder. 4. The work holding device according to claim 1, further comprising a pivot bearing between an upper end of the work holder and the upper arm or a member fixed to the upper arm. 5. The work holding device according to claim 1, wherein at least the fourth magnet is constituted by an electromagnet. 6. The work holding device according to claim 2, wherein at least one of the first magnet and the third magnet is constituted by an electromagnet.