JP2002096262A - Grinding device and holding method of work piece - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a grinding device capable of flatly grinding a plate surface of a work with high accuracy. SOLUTION: This grinding device simultaneously grinds both surfaces of the work 2 by cutting into the work 2 from upper and lower parts by rotating upper and lower grinding wheels 7. A intra-hole driven roller 5 is arranged to a center hole 2a provided to the work 2, and a driving roller 3 and an outer periphery driven roller 4 are also arranged to the outer periphery of the work 2, whereby the work 2 is rotatably supported by being held by the rollers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grinding apparatus for grinding a surface of a workpiece having a disk shape and a hole formed in a central portion thereof, and a method of holding the workpiece.

[0002]

2. Description of the Related Art Conventionally, a grinding apparatus for simultaneously grinding both surfaces of a workpiece by sandwiching a plate surface of a thinly cut disk-shaped workpiece (workpiece) between two rotating grindstones. It has been known. In the grinding device, since it is necessary to rotate the grindstone and also the workpiece, the outer periphery of the disk-shaped work is sandwiched by a plurality of rollers, and at least one of the rollers is rotationally driven. , Rotating the work. As an example, FIGS. 10 and 11 schematically show a grinding apparatus. FIG. 10 is a perspective view showing a state in which a workpiece is ground by a conventional grinding apparatus. FIG. 11 is a front view of the grinding apparatus as viewed from a direction perpendicular to the plate surface of the workpiece. Depiction of the grindstone is omitted. As shown in FIG. 10, the conventional grinding apparatus holds the plate surface of a disk-shaped work 102 so as to be perpendicular to the ground, and sandwiches the plate surface of the work 102 between two rotating grindstones 106 and 107. This is a device for grinding. Three guide rollers 10 are provided on the outer periphery of the work 102.
3, 104 and 105 are provided, and the outer peripheral surface of each guide roller is in contact with the outer peripheral surface of the work 102. As shown in FIG. 11, when the driving roller 103, which is one of the guide rollers, is rotated counterclockwise by a work driving motor (not shown), the outer peripheral surface of the driving roller 103 contacts the outer peripheral surface of the work 102. The work 102 rotates clockwise due to the frictional force of the part. And
As shown in FIG. 10, two grindstones 106 and 107 rotating in a counterclockwise direction opposite to the rotation direction of the work 102.
Thus, the plate surface of the work 102 is sandwiched from both sides, and both the grindstones 106 and 107 are cut in the direction of the work 102, thereby simultaneously grinding the front and back surfaces of the work 102.

As described above, in the case of the supporting method in which the outer peripheral portion of the disk-shaped work 102 is held between the guide rollers, FIG.
As shown in FIG. 1, at least three rollers are required, and three more rollers have acute angles of all triangles formed by connecting the contact points between the respective outer peripheral surfaces and the outer peripheral surface of the work 102. It is necessary to arrange them so as to form an acute triangle.

[0004]

According to the above-mentioned conventional grinding apparatus, the outer periphery of a thin disk-shaped work 102 is sandwiched between a plurality of guide rollers 103, 104 and 105, and a rotation operation is given by the rotation of a drive roller 103. It has a structure. Therefore, in order to prevent the drive roller 103 from running idle, it is necessary to press at least one roller, for example, the roller 105, from the outer periphery of the work 102 toward the center of gravity of the triangle.

The work 10 is guided by a guide roller.
In the case of a structure in which the outer circumference of the roller 2 is held, a triangular distortion region 108 formed by at least three rollers 103, 104, and 105 (a hatched portion rising to the right in FIG. 11) is pressed by the roller 105. Distortion will occur. Further, the grinding area 109 where the grinding is performed by the rotary grindstones 106 and 107 (the hatched portion in the lower right direction in FIG. 11) must extend at least from the outer peripheral portion of the work 102 to the center hole 102a. Therefore, a triangular distortion region 108 in which distortion due to the pressing of the roller 105 has occurred.
And the grinding areas 109 where the grinding is performed by the action of the grindstones 106 and 107 are overlapped. In the overlapping strain grinding area 110 (the cross section of the hatched portion in FIG. 11), the pressing of the roller 105 is performed. Thus, the work 102 in the state where the distortion is generated is ground by the rotating grindstones 106 and 107 to achieve flattening.

However, in this case, when the grinding is completed, the work 105 is removed from the guide roller by retreating the pressed roller 105, the work 102 is distorted by the pressing of the roller 105, and the work 102 is restored.
Is distorted instead of flat. That is, the roller 1
Since the work 102 distorted by the pressing of the workpiece 05 is ground to flatten it, if the pressing of the roller 105 is released and the distortion returns to its original state, the work surface flattened by the grinding will be distorted in reverse. Will be.

The invention according to the present application has been made to solve the above-mentioned problems, and an object of the invention is to grind a plate surface of a work with high precision and flatness. An object of the present invention is to provide an apparatus and a method for holding a workpiece.

[0008]

In order to achieve the above object, a first aspect of the present invention provides a disk-shaped workpiece provided with a circular hole at the center while supporting the disk-shaped workpiece by a support mechanism. A grinding device that rotates and grinds a plane of the workpiece by a rotating grindstone, wherein the support mechanism arranges a roller at least in a hole provided in the workpiece, and forms a roller on an outer periphery of the workpiece. A grinding roller, wherein the workpiece is held between the rollers to support the workpiece.

According to a second aspect of the present invention, the support mechanism is provided in a plurality on a rotatable work support table.
The grinding apparatus according to the first invention, wherein a position can be indexed to at least two positions of a workpiece grinding side facing the grinding wheel and a workpiece mounting side opposite to the grinding wheel.

Further, a third invention according to the present application is characterized in that a work rest is provided which is supported by the support mechanism and which holds a portion of the work being processed which is not supported by the grinding stone under static pressure. The grinding device according to the first or second aspect of the present invention.

A fourth invention according to the present application is characterized in that the work rest is provided on a work support table provided with the support mechanism, corresponding to the support mechanism. It is a grinding apparatus according to the invention.

Further, in a fifth aspect of the present invention, the work rest has a fluid ejection hole, and ejects a fluid from the fluid ejection hole to hold a workpiece under static pressure from both upper and lower surfaces or only from the lower surface. The grinding device according to the third or fourth aspect of the present invention,

According to a sixth aspect of the present invention, in the work rest, the ejection pressure of the fluid in the later stage of the grinding is higher than the ejection pressure of the fluid in the earlier stage of the grinding of the workpiece. The grinding apparatus according to the fifth aspect, wherein the ejection pressure is changed as described above.

Further, in a seventh invention according to the present application, the work rest holds the workpiece from both upper and lower surfaces under static pressure, and the work rest on the upper surface side of the workpiece is provided to be vertically movable by its own weight. A third or a fourth feature characterized in that
It is a grinding apparatus according to the invention.

An eighth invention according to the present application is characterized in that a plurality of the support mechanisms are provided around a grindstone by distributing an outer peripheral direction of the grindstone, and a plurality of workpieces can be ground simultaneously. The grinding device according to any one of the first to seventh inventions.

Further, according to a ninth aspect of the present invention, a thin plate-shaped workpiece is sandwiched by a jig having a fluid ejection hole.
A method for holding a workpiece under static pressure by ejecting a fluid from the fluid ejection hole, during grinding of the workpiece,
A method for holding a workpiece, wherein the ejection pressure of the fluid is changed.

According to a tenth aspect of the present invention, a thin plate-shaped workpiece is sandwiched by a jig having a fluid ejection hole, and fluid is ejected from the fluid ejection hole to hold the workpiece at a static pressure. A method of holding a workpiece, characterized in that the ejection pressure of the fluid in the later stage of grinding is higher than the ejection pressure of the fluid in the earlier stage of grinding the workpiece. .

Further, an eleventh invention according to the present application is characterized in that the jig sandwiches a thin plate-shaped workpiece from both upper and lower surfaces, and the jig on the upper surface side can be moved up and down by its own weight during processing. A method for holding a workpiece according to the ninth or tenth aspect of the present invention.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention according to the present application will be described below in detail with reference to FIGS. 1 to 6, 8 and 9.

FIG. 1 is an enlarged plan view showing the configuration of the grinding section from the overall view of the grinding apparatus 1 in the present embodiment shown in FIG. The work 2 has a substantially disk shape, and has a center hole 2a, which is a through hole, formed at the center of the work 2 to form a so-called disk. The disk-shaped work 2 is made of, for example, amorphous or crystallized glass. The size of the work 2 is assumed to be used for a hard disk which is an auxiliary storage device such as a computer. A description will be given of a case of grinding a workpiece 2 having a center hole diameter of about 20 mm, a workpiece thickness of 1 mm or less, of 2.5 inches. It should be noted that the present invention is not limited to the grinding of a workpiece having the above-mentioned size, and it goes without saying that various values can be taken according to the type of the workpiece.

First, the work 2 is cut out of a glass plate formed as a single thin plate into a disk shape by, for example, a press. This glass plate material is not necessarily formed flat with high precision, and the glass plate itself may have distortion, undulation, or the like. Also, since the pressure is applied by a punching process such as a press, the center hole 2
a and the outer peripheral portion are slightly deformed. When the cut work 2 is used for a hard disk or the like of a computer, the work 2 is rotated at an extremely high speed, and therefore, particularly, flatness is required.

Therefore, the cut work 2 is ground by the grinding apparatus 1 of the present embodiment shown in FIGS. FIG. 2 is a longitudinal sectional view showing a sectional structure of a grinding section of the grinding device 1. As shown in FIG. 2, the grinding apparatus 1 according to the present embodiment is arranged such that the plate surface of the work 2 is parallel to the reference surface 14 a of the bed 14 (see FIG. 8). Is sandwiched between the upper grinding wheel 6 and the lower grinding wheel 7 to perform grinding. The upper grindstone 6 is provided with an annular grinding grindstone 6a on a disk-shaped upper grindstone base 6b, and performs the same function as a so-called cup grindstone. The grinding wheel 6a is a diamond wheel, and is formed by bonding diamond abrasive grains with a binder, and is generally used for grinding a workpiece made of a hard and brittle material.

The upper grindstone 6 is fixed to the upper grindstone shaft 8 by fastening a flange 8a formed at the tip of an upper grindstone shaft 8 for rotating the grindstone and an upper grindstone base 6b with bolts 8b. The upper grindstone shaft 8 is a rotation axis of the upper grindstone 6, and is disposed perpendicular to the reference surface 14a of the bed 14 (see FIG. 8), so that a grinding action surface on which the grinding grindstone 6a acts on the workpiece. Is parallel to the reference surface 14a of the bed 14, that is, parallel to the plate surface of the work 2. Similarly, the lower whetstone 7
The lower wheel base 9b and the grinding wheel 7a are also fastened by bolts 9b to a flange 9a provided at the tip of the lower wheel shaft 9. The grinding wheel 7a is a diamond wheel, and the grinding surface of the grinding wheel 7a is arranged parallel to the plate surface of the work 2. In the present embodiment, the cup-shaped grindstone is used as described above, but the present invention is not limited to these, and a flat grindstone or a segment grindstone having a circular grinding action surface may be used. it can.

FIG. 8 is a longitudinal sectional view showing an overall view of the present grinding apparatus 1. The main grinding device 1 includes a lower grinding wheel 7, a work support mechanism 12, a grinding wheel correction device (not shown), and the like.
It is provided in. An upper grindstone 6 is provided on a column 23 integrated with a top rail erected on the bed 14.
The bed 14 is provided with a control box 25.

As shown in the figure, the lower grinding wheel shaft 9 is integrally formed with the rotating shaft of the lower grinding wheel drive motor 11.
The rotor 11b is shrink-fitted and fixed. The rotation of the rotor 11b of the lower grindstone drive motor 11 causes the lower grindstone shaft 9 and the lower grindstone 7 to be rotationally driven. Similarly, although not shown, the upper grinding wheel shaft 8 serves as a rotating shaft of the upper grinding wheel drive motor, and rotation is given by rotation of the rotor of the upper grinding wheel drive motor.

The lower grindstone drive motor 11 is provided in the lower grindstone raising / lowering mechanism 30, and the lower grindstone raising / lowering mechanism 30 has a structure in which the lower grindstone 7 can be moved up and down. The lower whetstone lifting mechanism 30 includes a lower quill 33 and a Z-axis control motor 3.
4 and a Z-axis feed screw 35 and a nut 36. The Z-axis feed screw 35 is provided on the axis of the rotary shaft 34a of the Z-axis control motor 34 so as to be connected to the rotary shaft 34a. The rotation of the Z-axis control motor 34 causes the Z-axis feed screw 35 to rotate. The Z-axis control motor 34 is a servomotor, and is fixed to the bed 14.

A nut 36 screwed into a Z-axis feed screw 35 is fixed to the lower quill 33, and the nut 36 moves upward or downward as the Z-axis feed screw 35 rotates, The lower quill 33 moves up and down.
Since the lower wheel drive motor 11 has its stator 11 c fixed to the lower quill 33, the lower wheel drive motor 11 moves up and down according to the up and down movement of the lower quill 33.

Although not shown, the upper grinding wheel drive motor is also provided in the upper grinding wheel lifting mechanism 20 having the same configuration as the lower grinding wheel lifting mechanism 30. The feed screw feeds the nut,
The upper quill to which the nut is fixed performs the elevating operation. Since the stator of the upper grindstone drive motor is fixed to the upper quill, the upper grindstone drive motor moves up and down according to the up and down movement of the upper quill.

Next, the work supporting mechanism 12 for supporting the work 2 will be described with reference to FIGS. The work 2 punched from a glass plate by a press is rotatably held on a work support 13. As shown in FIG. 1, the work support table 13 includes a driving roller 3 serving as three guide rollers, an outer peripheral driven roller 4, an in-hole driven roller 5, a roller driving motor 18 for rotating the driving roller 3, and As shown in FIG. 2, an upper work rest 15 and a lower work rest 16 for holding the work 2 from above and below are provided.

Each of the three guide rollers 3, 4, and 5 has a disk shape.
Rotating shafts 3a, 4a, 5 in the direction perpendicular to
a and is rotatably held by the rotating shafts 3a, 4a and 5a. Each of the guide rollers 3, 4, and 5 is formed to be thicker than the work thickness so that the outer peripheral portion of the work 2 and the center hole 2a can be reliably sandwiched. The material of the guide rollers 3, 4, and 5 is the work 2
A material that is softer than the material of the work 2 and has a certain degree of elasticity so as not to damage the work 2 is used. In the present embodiment, a material having a certain degree of elasticity and hardness, such as urethane or plastic, is used.

As shown in FIG. 1, the driving roller 3 is fixed to a rotating shaft 3a rotatably supported on the work support table 13, and a pulley 3b is fixed to the rotating shaft 3a under the driving roller 3. Have been. A belt 17 is hung on the pulley 3b, and the belt 17 is provided in an elongated ring shape on a plane parallel to the table surface 13b of the work support table 13. One end of the belt 17 is hung on the pulley 3b, and the other end is a rotating shaft 18 of a roller driving motor 18.
It is hung on a pulley 18b fixed to a.

The rotation of the roller drive motor 18 causes the belt 17 to rotate via the pulley 18b,
7, the rotational power of the roller drive motor 18 is transmitted to the drive roller 3. The outer periphery of the drive roller 3 is in contact with the outer periphery of the work 2, and the rotation of the drive roller 3 causes the work 2 to rotate.
Performs rotation. In FIG. 1, the roller drive motor 18
Rotates counterclockwise, and the drive roller 3 also rotates counterclockwise by the belt 17. Thereby, the driving roller 3
Is rotated clockwise. The outer peripheral surface of the outer peripheral driven roller 4 is in contact with the outer peripheral surface of the work 2,
As the work 2 rotates, the outer peripheral driven roller 4 rotates counterclockwise.

In the center hole 2a of the work 2, an in-hole driven roller 5 is disposed, and the outer peripheral surface of the roller 5 is located in the center hole 2a.
a, the driven roller 5 in the hole also rotates clockwise as the work 2 rotates. The roller diameter of the in-hole driven roller 5 is formed to be at least smaller than the diameter of the center hole 2a of the work 2 so that the upper and lower grinding wheels 6, 7 do not contact the in-hole driven roller.

In this embodiment, the work 2
Although two rollers, a driving roller 3 and an outer peripheral driven roller 4, are arranged as guide rollers arranged on the outer periphery, the present invention is not limited to these forms, and three or more rollers are arranged on the outer periphery. It may be. Further, the drive roller does not necessarily need to be disposed on the outer periphery, and a structure in which the roller in the center hole 2a is driven may be used.

The work support 13 is provided with a holding frame 40 for holding the upper work rest 15. The holding frame 40 has a crank shape as shown in FIG. 2, and one end of the holding frame 40 is fastened and fixed to the work support 13 by bolts 41. An upper work rest 15 is held above the work 2 of the holding frame 40. A plurality of ejection holes 15a are formed on the surface of the upper work rest 15, and the ejection holes 15a are connected to a pump (not shown) for supplying a fluid. Upper work rest 15
Is the same as the planar shape of the lower work rest 16 (see FIG. 3), and overlaps in the vertical direction.

Above the upper work rest 15, there is provided a hanging member 42 having a key portion 42a which is convex to the left and right. Further, a lifter 43 having a claw portion 43a that engages with a key portion 42a of the hanging member 42 is provided.
2 is fitted to the lifter 43 so as to be vertically movable.
Guide holes 43b are formed at both left and right ends of the lifter 43, and a guide shaft 44 is fitted into the guide holes 43b. The guide shaft 44 is fixed to the holding frame 40 and hangs down. The guide shaft 44 is provided vertically downward from the holding frame 40 with respect to the platform 13 b of the work support 13, and the guide hole 43 b is also formed perpendicular to the platform 13 b of the work support 13.

At the center of the upper surface of the lifter 43, the tip of the rod 45a of the hydraulic cylinder 45 is fixed. The cylindrical barrel 45b side of the hydraulic cylinder 45 is fixed on the holding frame 40, and two oil feed pipes 46a and 46b for supplying or discharging oil into and from the barrel 45b are provided. In the present embodiment, the hydraulic cylinder 4
5, the present invention is not limited to this, and it goes without saying that a screw feed structure or the like can be applied as long as the lifter 43 can be moved up and down.

The lifter 43 moves up and down as the rod 45a of the hydraulic cylinder 45 moves up and down. A guide shaft 44 hung from the holding frame 40 is slidably fitted in a guide hole 43 b provided in the lifter 43, so that the lifter 43 is guided by the guide shaft 44 and the lifter 43 is placed on the surface of the work support table 13. 13b is vertically moved.

The lifter 43 is provided with a space 43c so that the key portion 42a can be engaged with play upward. Therefore, when the lifter 43 is lowered to bring the upper work rest 15 close to the upper surface of the work 2, the upper work rest 15 is held in a state of floating above the work 2 due to the reaction force of the gas ejected from the upper work rest 15. Is done. At this time, the engagement between the key portion 42a and the claw portion 43a is released, and the key portion 42a is held in the space 43c so as to be separated upward from the claw portion 43a. This takes into account that the work 2 becomes thinner as the work 2 is ground during the grinding process, and when the gap between the upper work rest 15 and the work 2 changes, the upper work rest 15 can move up and down by its own weight from the balance with buoyancy. It is like that. The space 43c of the lifter 43 is formed in such a size that the key portion 42a does not rattle in the left-right direction.
a is held without swinging left and right.

Next, a mechanism for pressing the lower work rest 16 and the drive roller 3 against the work 2 will be described.
FIG. 3 is a plan view showing a state in which the bolts 41 fixing the holding frame 40 in FIG. 1 are removed, the holding frame 40 is removed from the work support 13, and the upper grindstone 6 is further removed.

The lower work rest 16 shown in FIG. 3 is disposed on the work support 13 and is fixed on the work support 13 without moving up and down. Lower work rest 16
Are formed with a plurality of ejection holes 16a, and the ejection holes 16a are connected to a pump (not shown) for supplying a fluid. The lower work rest 16 ejects a fluid such as air through the ejection hole 16a from below to above, so that the work 2 is placed on the lower work rest 16.
Is held in a floating state.

The ejection hole 15 of the upper work rest 15
Fluid is ejected downward from a, and the upper and lower surfaces of the work 2 are sandwiched between the upper work rest 15 and the lower work rest 16 to hold the work 2 at a static pressure. In the present embodiment, the ejected fluid uses air, but the ejected fluid may be a gas or a liquid, and the use of the grinding fluid may serve as both the grinding fluid and the work static pressure holding in the grinding action section. it can.

The upper and lower work rests 15 and 16 hold the area other than the area where the work 2 is ground by the upper and lower whetstones 6 and 7 using static pressure. Work rest 1 on the outer circumference of grinding stones 6 and 7
5 and 16 are provided to hold the work 2 under static pressure.

As shown in FIG. 2, the fixed shaft 5a of the driven roller 5 in the hole is fixed to a support rod 47 provided on the back of the work support table 13. A plate-shaped support portion 47a is provided at the tip of the support rod 47, and the fixed shaft 5a is fixed to the support portion 47a vertically above the plate surface of the support portion 47a. Since the plate surface of the support portion 47a is arranged so as to be parallel to the table surface 13b of the work support table 13, the fixed shaft 5a is held in a state perpendicular to the table surface 13b of the work support table 13. An in-hole driven roller 5 is rotatably attached to the fixed shaft 5a.

The guide member 4 is provided on the back surface of the work support 13.
8 are provided. The guide member 48 includes a support rod 47.
Is parallel to a straight line connecting the centers of the upper and lower whetstones 6 and 7 and the center of the work 2 (on a straight line when viewed from above), and in a longitudinal direction in a plane parallel to the base surface 13b of the work support base 13 (FIG. (Horizontal direction). The guide member 48 supports the back surface of the support rod 47 so that the support rod 47 does not move away from the work support base 13 by bending. The guide is parallel to the extension line connecting the centers of the.

The other end 49b of the tension coil spring 49 whose one end 49b is fixed to the work support 13 is hooked to the end 47b of the support rod 47 opposite to the end where the support portion 47a is provided. In addition, the driven roller 5 in the hole is urged by the tension coil spring 49 in a direction away from the upper and lower grinding wheels 6 and 7.

As shown in FIG. 3, when the driven roller 5 in the hole presses the center hole 2a against the inner peripheral surface, a disk-shaped contact is formed between the driven roller 5, the driving roller 3 and the driven roller 4 at the outer periphery. The work 2 is held flat.

At this time, the three guide rollers 3, 4, 5
3. A triangular distortion region 108 (a hatched portion rising to the right in FIG. 3) formed by connecting the outer peripheral surface of the workpiece 2 and the contact point of the outer peripheral surface of the work 2;
Since the grinding areas 109 of the upper and lower whetstones 6 and 7 (hatched portions in the lower right portion of FIG. 3) do not overlap, the distortion of the work 2 due to the pressure of the driven roller 5 in the hole does not affect the grinding area 109, and the distortion is reduced. An area where no occurrence has occurred can be ground flat.

Therefore, after the grinding is completed, the driven roller 5
When the pressurization is released, the workpiece 2 is not distorted and can be ground flat with high precision. As shown in FIG.
At the end portion 47b of the support rod 47 on which a is hooked, a release shaft 50 is provided vertically upward, and an arm member 51 provided with a long hole 51a fitted to the release shaft 50 is provided.
Is installed. The root side of the arm member 51 is fixed to a rotation shaft 52a of an arm drive motor 52 fixed to the work support table 13, and the rotation of the arm drive motor 52 causes the arm member 51 to rotate around the rotation shaft 52a. Perform the action. As the arm drive motor 52, a torque motor, a rotary solenoid, a fluid pressure rotary motor, or the like is employed.

A long hole 51a is formed at the tip of the arm member 51, and the release shaft 50 is inserted into the long hole 51a.
Since it is provided so as to be movably fitted inside a, the in-hole driven roller 5 moves in the direction approaching the upper and lower grinding wheels 6 and 7 (leftward in FIG. 3) in accordance with the operation of the arm member 51. The arm member 51 is used to remove the work 2 from the work support table 13. When the grinding is completed, the arm drive motor 52 rotates counterclockwise, and the arm member 51
1 rotates counterclockwise against the spring force of the tension coil spring 49. At that time, the long hole 51a of the arm member 51
The side moves in a direction approaching the upper and lower whetstones 6 and 7, and the pressurization of the work 2 by the driven roller 5 in the hole is released.
Can be removed.

When the driven roller 5 in the hole is pressed against the work 2, the supply of the electric power to the arm drive motor 52 is stopped so that the arm member 51 can freely rotate.
The driven roller 5 in the hole is pressed against the work 2 by the force of the tension coil spring 49.

As shown in FIG. 4, the work support table 13 is provided with the work support mechanism 12 configured as described above.
It is provided on both sides symmetrically with respect to the center of the work support 13. Hereinafter, the side closer to the upper and lower grindstones 6 and 7 of the work support table 13 is referred to as a work grinding side, and the side farther from the upper and lower grindstones 6 and 7 is referred to as a work mounting side. Is appended with “′” and the description is omitted.

As shown in FIG. 8, at the center of the work support 13, a support rotating shaft 13a is fixed. The support base rotating shaft 13a is provided with a bearing house 37 fixed to the bed 14.
Are rotatably supported by bearings 38. The support base rotation shaft 13a is connected to a rotation shaft 53a of a support base drive motor 53 fixed to the bearing house 37. When the support driving motor 53 rotates, the support rotating shaft 13 a fixed on the rotating shaft 53 a rotates, and the work support 13 rotates with respect to the bed 14. At this time, the work support table 1
3 rotates on a plane parallel to the reference surface 14a of the bed 14. Note that the support base drive motor 53 is a servomotor that can be indexed by 180 degrees rotation. Next, the operation of the grinding device 1 will be described.

A glass disk formed by punching from a glass plate is mounted on a work support 13. The work support table 13 has two work support mechanisms 12,
The work 2 is mounted on the upper and lower whetstones 6,
7 is performed in the work supporting mechanism 12 'located on the work mounting side opposite to the work mounting side.

[Description of Work Mounting Side] As shown in FIG. 5, the upper work rest 15 'of the work supporting mechanism 12' located on the work mounting side is supplied with oil from the oil feed pipe 46b 'of the hydraulic cylinder 45'. Since the oil is discharged from the oil feed pipe 46a 'side, the piston 45 in the hydraulic cylinder 45' is
c 'is located above, and the upper work rest 15' is located above.

As shown in FIG. 6, the work 2 is mounted by the transfer mechanism 54. Unground work cassette 70
(See FIG. 9), the transport mechanism 54 holding the outer periphery of the unground work 2 with the plate surface of the work 2
The work 2 is conveyed to the work support mechanism 12 'in a state where the work 2 is parallel to the platform 13b. As shown in FIG.
In the work supporting mechanism 12 'on the work mounting side, since the upper work rest 15' is in the raised state, the work 2 is transported between the upper work rest 15 'and the driven roller 5' in the hole, and the center hole 2a of the work 2 is It is arranged so as to be located above the driven roller 5 'in the hole.

When the center hole 2a of the work 2 reaches the upper part of the driven roller 5 'in the hole, the work 2 is slowly placed on the lower work rest 16'. Then, the oil feed pipe 46a '
The piston 45c 'is lowered by supplying the oil from the oil supply pipe and discharging the oil from the oil feed pipe 46b' to lower the upper work rest 15 ', and the work 2 is sandwiched between the upper and lower work rests 15' and 16 '. Hold. At this time, the ejection holes 15a 'on the upper and lower work rests 15', 16 '
Since air is jetted from 16a ', the work 2 is held in a non-contact state between the work rests 15' and 16 'by static pressure.

Since the hanging member 42 'of the upper work rest 15' is fitted to the lifter 43 'so as to be able to move up and down, the upper work rest 15' is provided with the ejection hole 15a 'of the upper work rest 15'. The upper work rest 15 'is kept floating at a position where the buoyancy of the gas ejected from the air and the weight of the upper work rest 15' are balanced. This takes into account that the work 2 becomes thinner as the work 2 is ground during the grinding, and when the gap between the upper work rest 15 ′ and the work 2 changes,
The upper work rest 15 'can be moved up and down by its own weight from the balance with buoyancy.

After lowering the upper work rest 15 ',
The work holding portion 54a of the transfer mechanism 54 is opened to release the work 2, and the transfer mechanism 54 is retracted.

Next, the arm drive motor 52 'shown in FIG.
Is released to allow the arm member 51 'to freely rotate, and the in-hole driven roller 5' is pressed against the unground work 2 by the spring force of the tension coil spring 49 '.
Perform positioning. The work 2 has a center hole 2a of the work 2.
4 is pressed to the left in FIG. 4 by an in-hole driven roller 5 ′, and is supported and positioned at three points by a driving roller 3 ′ and an outer peripheral driven roller 4 ′ arranged on the outer periphery of the work 2.

After the grinding of the workpiece 2 on the workpiece grinding side is completed, the workpiece support 13 is rotated clockwise by 180 ° about the support platform rotation shaft 13a, so that the grinding on the workpiece grinding side is completed. Work 2 moves to the work mounting side, and the unground work 2 previously attached to the work mounting side moves to the work grinding side.

Subsequently, on the work mounting side, the outer periphery of the work 2 after the grinding is clamped by the transfer mechanism 54 in the work support mechanism 12 '. By pressing the arm member 51 'shown in FIG. 4 counterclockwise around the rotation shaft 52a' of the arm drive motor 52 ', the pressing of the workpiece 2 by the driven roller 5' in the hole is released. afterwards,
As shown in FIG. 5, oil is supplied from the oil feed pipe 46b '
The piston 45c 'is raised by discharging from the a', and the upper work rest 15 'is raised.

The transport mechanism 54 raises the plate surface of the work 2 to the upper part of the driven roller 5 ′ in the hole while keeping the plate surface of the work 2 parallel to the base surface 13 b of the work support table 13,
The workpiece support mechanism 1 is moved in parallel with the
The work 2 after grinding is removed from 2 '.

Then, as shown in FIG. 9, the removed work 2 after grinding is stored in the already-ground work cassette 71.

Then, the transport mechanism 54 moves the unground work 2
Is taken out of the unground work cassette 70, and the unground work 2 is mounted on the work supporting mechanism 12 'on the work mounting side as described above.

[Description of Work Grinding Side] Next, the work grinding side will be described. As shown in FIG. 2, on the work grinding side, the work 2 is ground by cutting upper and lower grindstones 6 and 7 into the unground work 2 held by the work support mechanism 12 from above and below. The upper grindstone 6 and the lower grindstone 7 rotate around the grindstone rotating shafts 8 and 9 by the rotation of the upper grindstone drive motor 10 and the lower grindstone drive motor 11, respectively. In the present embodiment, the upper grindstone 6 and the lower grindstone 7 rotate in opposite directions, and when viewed from above, the upper grindstone 6 rotates clockwise as shown in FIG. As shown, the lower grindstone 7 rotates counterclockwise.

However, the upper grindstone 6 and the lower grindstone 7 do not always need to be rotated in opposite directions, but may be rotated in the same direction. When the upper and lower grindstones 6 and 7 are rotated in the same direction as the work 2, upcuts are performed on the upper and lower surfaces of the work 2, and the upper and lower grindstones 6 and 7 are rotated in the opposite direction to the work 2. In this case, the upper and lower surfaces of the work 2 are cut down.

First, the lower grindstone 7 is raised by the lower grindstone raising / lowering mechanism 30 to a position just before contact with the lower work surface of the work 2, and the upper grindstone 6 is brought into contact with the upper work surface of the work 2 by the upper grindstone lift mechanism 20. Down to a position just before

The drive roller 3 is rotated by rotating the roller drive motor 18 to rotate the annular belt 17 hung on the pulley 18b. The outer peripheral surface of the drive roller 3 is in contact with the outer peripheral surface of the work 2, and the work 2 is rotated by a frictional force generated between the outer peripheral surface of the drive roller 3 and the outer peripheral surface of the work 2. At this time, the diameter of the upper and lower whetstones 6 and 7 was 350 mm, and the rotation speed was 500 to 3000 rpm. p.
m, more preferably 500 to 1500 r. p. m
It is. The diameter of the work 2 is 96 mm, and the rotation speed is 2 to 100 r. p. m, more preferably 2 to 20
r. p. m.

After the work 2 is rotated, the upper and lower surfaces of the work 2 are simultaneously ground by cutting the upper grindstone 6 and the lower grindstone 7.

At this time, since the unground work 2 has warpage and uneven thickness, the upper and lower work rests 15 and 16
It is not preferable to forcibly flatten and grind the workpiece 2 by the pressure of the ejection fluid from the ejection holes 15a and 16a. Therefore, in the initial stage of the grinding process, the ejection pressure of the fluid (air) from the ejection holes 15a, 16a of the upper and lower work rests 15, 16 is reduced, and the correcting force of the upper and lower work rests 15, 16 is applied to the work 2. Keep it from working. When sufficient flatness is obtained by removing warpage and thickness unevenness after grinding for a while, the pressure of the fluid ejected from the upper and lower work rests 15 and 16 is increased, and the work 2 is held strongly. Perform grinding.
That is, in the initial stage of the grinding process, the pressure of the ejected fluid is controlled to be low, and in the later stage of the grinding process, the pressure of the ejected fluid is controlled to be increased. in this way,
By changing the pressure of the fluid ejected from the work rest during the grinding process, the thin plate-shaped work can be ground flat with high precision. At this time, the upper work rest 15 maintains the balance between its own weight and buoyancy,
It moves up and down with respect to the lifter 43 and maintains a floating state at a balanced position.

The cutting of the grindstone is performed by lowering the upper grindstone 6 toward the work 2 and simultaneously raising the lower grindstone 7 toward the work 2. The cutting speed of the grindstone at this time is about 50 to 1000 μm / min, and more preferably 50 to 400 μm / min.

By the above-mentioned method, the upper and lower grinding wheels 6, 7 are cut until the work 2 has a desired thickness. At this time, FIG.
As shown in FIG. 7, a distortion region 108 formed by a contact point between the outer peripheral surface of the three guide rollers (the driving roller 3, the outer peripheral driven roller 4, and the inner driven roller 5) and the outer peripheral surface of the work 2.
Since the (upward diagonally shaded portion) does not overlap with the grinding area 109 of the work 2 being ground by the upper and lower whetstones 6 and 7 (downward diagonally shaded part), the grinding area 109 of the work 2 is formed by the in-hole driven roller 5. Not affected by distortion due to pressing,
Highly flat grinding is possible.

After cutting the upper and lower grindstones 6 and 7 to a desired position, the upper grindstone 6 is lifted away from the work 2, and at the same time, the lower grindstone 7 is lowered away from the work 2 to lower the upper and lower grindstones 6 and 7. Evacuation. Upper and lower whetstones 6,7
Is stopped, the rotation of the roller drive motor 18 is stopped,
Stop two rotations of the work. Then, the work support 13 is rotated 180 ° counterclockwise around the support shaft 13a, and the ground work 2 is moved to the work mounting side.

With the rotation of the work support 13, the unground work 2 mounted on the work support mechanism 12 ′ on the work mounting side is transported to the work grinding side, and the grinding is performed as described above. Note that the rotation direction of the work support table 13 may be only one direction, but the accuracy of the mechanism can be improved by adopting a structure in which clockwise rotation and counterclockwise rotation are alternately repeated.

As described above, the work is ground by repeating the attachment and detachment of the work 2 in the work support mechanism 12 'on the work mounting side and the grinding of the work 2 on the work grinding side. As described above, while the workpiece 2 is being ground on the workpiece grinding side, the already-ground workpiece and the unground workpiece are exchanged in the workpiece support mechanism 12 'on the workpiece mounting side, so that the grinding can be performed efficiently. .

FIG. 9 is a conceptual view of the entire grinding apparatus 1 as viewed from above. The main grinding apparatus 1 is provided with the work support table 1 described above.
3 are provided. As shown in FIG.
A pair of work supports 13 is provided, and the direction of the outer periphery of the grindstone is divided into four equal parts, and the directions of the respective work supports 13 are rotated by 90 ° and arranged. The operation of each work support 13 is as described above.

As described above, by providing a plurality of work supporting mechanisms 13, a plurality of works 2 can be ground at the same time, and the time required for the grinding operation can be reduced.
Further, since a plurality of works 2 are arranged between the upper and lower grinding wheels 6, 7, the grinding balance of the upper and lower grinding wheels 6, 7 is good, and the grinding can be stably performed. Although four sets of work supports 13 are provided in the grinding device 1 shown in FIG. 9, the number of work supports 13 is not limited to four sets, and the same effect can be obtained if two or more sets are provided. It is obtained. For example, when providing three sets of work supports,
The circumference of the whetstone is divided into three equal parts, and the direction of the work support is 120 °
What is necessary is just to rotate and arrange each.

Next, another embodiment of the work support will be described with reference to FIG. FIG. 7 shows the work support 56.
FIG. 3 is a plan view showing a configuration on the workpiece grinding side of FIG. Note that parts different from the above-described embodiment are indicated by two-dot chain lines,
The same parts are denoted by the same reference numerals and the description is omitted.

In this embodiment, the work support 5
One end 49 b of a tension coil spring 49 attached to the back surface of the work support 6 is connected to a rod 57 a of a hydraulic cylinder 57 provided on the back surface of the work support 56. And
A hydraulic cylinder 57 is used instead of the arm member 51 shown in FIG.
Presses and releases the driven roller 5 in the hole. Oil feed pipes 58a and 58b are connected to the hydraulic cylinder 57 to supply oil before and after a piston 57c in the barrel 57b. The oil supply pipes 58 a and 58 b are supplied and discharged with pressure oil by a pump 59 via a four-way switching valve 62.

Since the tension coil spring 49 is arranged between the hydraulic cylinder 57 and the driven roller 5 in the hole, the driven roller 5 in the hole presses and holds the work 2 by the force of the hydraulic cylinder 57 and the force of the tension coil spring 49. I do.
At this time, the tension coil spring 49 is
A spring that is slightly stronger than the tensile force of

As described above, by disposing the tension coil spring 49 between the hydraulic cylinder 57 and the driven roller 5 in the hole, the vibration generated during the grinding is made to follow the tension coil spring 49, and the holding force for the work 2 is maintained. Can be processed while maintaining a constant.

The work support 56 includes a control unit 60.
Is provided. The controller 60 controls the roller drive motor 18
And controls the rotation of the roller drive motor 18. The outer peripheral driven roller 4 is provided with a detection unit 61 for detecting the rotation speed N2 of the outer peripheral driven roller 4. Information on the rotation speed N2 of the outer peripheral driven roller 4 detected by the detection unit 61 is sent to the control unit 60. Further, the control unit 60 controls the rotation of the roller drive motor 18, and can know the rotation speed N 1 of the drive roller 3 from the control target rotation speed of the roller drive motor 18.

Generally, the outer peripheral driven roller 4 rarely idles with respect to the work 2. Therefore, when the peripheral speed of the drive roller 3 is higher than the peripheral speed of the outer peripheral driven roller 4, the drive roller 3 It is thought that it is spinning against. In the present embodiment, since the roller diameters of the driving roller 3 and the outer peripheral driven roller 4 are the same, N1>
In the case of N2, the outer peripheral surface of the drive roller 3 slips with respect to the outer peripheral surface of the work 2 and runs idle.

The control unit 60 calculates the difference between the rotation speed N1 of the driving roller 3 and the rotation speed N2 of the outer peripheral driven roller 4. When N1−N2> 0, the outer peripheral surface of the driving roller 3 Is determined to be idling with respect to the outer peripheral surface of. When the idle rotation of the driving roller 3 is detected, the control unit 60 controls the pressure control valve 6 for controlling the discharge pressure of the pump 59.
3 or the rotation speed of the pump 59 is controlled. As described above, the idle rotation is detected from the difference between the peripheral speeds of the driving roller 3 and the outer peripheral driven roller 4, and the idling is detected and fed back to the pressing force of the driven roller 5 in the hole.
The work 2 can be appropriately held while preventing the driving roller 3 from running idle.

As described above, according to the present invention, when the workpiece 2 having the center hole 2a is ground, at least one guide roller (in-hole driven roller 3) is arranged in the center hole 2a, so that the guide is provided. The distortion region 108 formed by the roller and the grinding region 109 of the grindstone can be prevented from overlapping, and the thin plate-shaped work can be ground flat with high precision.

Further, by changing the holding force of the upper and lower work rests 15 and 16 in accordance with the elapse of grinding time, distortion and undulation of the thin plate-like work can be efficiently removed.

Further, idling of the driving roller 3 is detected from the difference between the peripheral speed of the driving roller 3 and the peripheral speed of the outer peripheral driven roller 4, and
By feeding back to the pressing force of the driven roller 5 in the hole, the work 2 can be prevented from running idle and can be ground efficiently.

In the present embodiment, an example of grinding using a so-called double-headed grinding machine has been described. However, the present invention focuses on how to hold a disk-shaped work. It is not limited to double-ended grinding machines. In addition, depending on the work 2, the upper work rest 15 may be unnecessary, and may be held only by the lower work rest 16.

As described above, according to the present invention, the disc-shaped work 2 having the circular center hole 2a at the center is rotated while being supported by the work supporting mechanism 12, and the work is rotated by the rotating grindstone (6 or 7). In the grinding device for grinding a flat surface of the work 2, the work supporting mechanism 12 has an in-hole driven roller 5 disposed at least in a center hole 2a provided in the work 2, and a roller (the drive roller 3 or the outer periphery) This is a grinding device 1 in which a driven roller 4) is arranged, and the work 2 is nipped and supported by the roller.

A plurality of work support mechanisms 12 are provided on a rotatable work support table 13, and upper and lower grinding wheels 6, 7 are provided.
The grinding device 1 is capable of indexing at least two positions, ie, a work grinding side facing the work and a work mounting side opposite to the work grinding side.

Further, the grinding apparatus 1 is provided with a work rest 16 (and 15) which is supported by the work supporting mechanism 12 and which holds a portion not supported by the upper and lower grindstones 6 and 7 of the work 2 being ground under static pressure. . The work rest 16 (and 15) is provided on the work support table 1 provided with the work support mechanism 12.
3 is provided corresponding to the work support mechanism 12.

[0093] The work rest 16 (and 15)
6a (and 15a), and the ejection holes 16a (and 15
The grinding device 1 is characterized in that a fluid is ejected from a) and the work 2 is held under static pressure from both upper and lower surfaces or only from the lower surface. Also, at the work rest 15 (or 16),
The ejection pressure is changed so that the ejection pressure of the fluid in the later stage of the grinding becomes higher than the ejection pressure of the fluid in the earlier stage of the grinding of the workpiece 2.

Further, the work rests 15 and 16 hold the work 2 from both upper and lower surfaces under static pressure, and the upper work rest 15 on the upper surface side of the work 2 is the grinding device 1 provided to be vertically movable by its own weight.

The grinding device 1 is characterized in that a plurality of work support mechanisms 12 are provided around the grindstones 6 and 7 by distributing the outer circumferential direction of the grindstones 6 and 7, and a plurality of works 2 can be ground simultaneously. is there.

The invention according to the present application relates to a work 2 in the form of a thin plate.
The work rest 15, which has the ejection holes 15a and 16a,
A method for holding a work 2 under static pressure by ejecting a fluid from the ejection holes 15a and 16a and sandwiching the work 2 by a pressure, wherein the ejection pressure of the fluid is changed during grinding of the work 2. Is the way.

Further, the work 2 having a thin plate shape is inserted into the ejection hole 15.
a method of holding the work 2 at a static pressure by sandwiching the work 2 between the work rests 15 and 16 and having the work holes 15a and 16a and ejecting a fluid from the ejection holes 15a and 16a. In addition, this is a work holding method characterized in that the ejection pressure of the fluid in the latter stage of the grinding is higher.

Further, the work rests 15 and 16 sandwich the thin plate-shaped work 2 from both upper and lower surfaces, and the upper work rest 15 on the upper surface side can be moved up and down by its own weight during processing. .

[0099]

According to the present invention, in the grinding of a thin plate-like work, the plate surface of the work can be ground flat with high precision.

[Brief description of the drawings]

FIG. 1 is an enlarged plan view showing a grinding section of the present grinding apparatus.

FIG. 2 is an enlarged longitudinal sectional view showing a section of a grinding section of the present grinding apparatus.

FIG. 3 is a schematic diagram illustrating a positional relationship among a grindstone, a guide roller, and a work in a grinding unit.

FIG. 4 is a plan view showing the overall configuration of a work support base.

FIG. 5 is a longitudinal sectional view showing the entire configuration of the work support base.

FIG. 6 is a plan view showing how the work is mounted on the work mounting side of the work support base.

FIG. 7 is a schematic diagram showing a control structure of a work support base and a guide roller according to another embodiment.

FIG. 8 is a longitudinal sectional view of the entire grinding device of the present invention.

FIG. 9 is a conceptual plan view of the entire grinding device of the present invention as viewed from above.

FIG. 10 is a perspective view of a grinding unit of a conventional grinding device.

FIG. 11 is a plan view showing a state of a grinding unit of a conventional grinding device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Grinding apparatus 2 ... Work 2a ... Center hole 3 ... Driving roller 3a ... Rotating shaft 3b ... Pulley 4 ... Peripheral driven roller 4a ... Rotating shaft 5 ... In-hole driven roller 5a ... Fixed shaft 6 ... Upper grindstone 6a ... Grinding grindstone 6b ... Upper whetstone stand 7 ... Lower whetstone 7a ... Grinding whetstone 7b ... Lower whetstone head 8 ... Upper whetstone shaft 8a ... Flange part 8b ... Bolt 9 ... Lower whetstone shaft 9a ... Flange part 9b ... Bolt 11 ... Lower whetstone drive motor 11b ... Rotor 11c …
Stator 12 Work support mechanism 13 Work support 13a Support support rotating shaft 13b
Table surface 14 Bed 14a Reference surface 15 Upper work rest 15a Spout hole 16 Lower work rest 16a Spout hole 17 Belt 18 Roller drive motor 18a Rotating shaft 18b Pulley 20 Upper whetstone lifting mechanism 23 Column 24 ... Z-axis control motor 25 ... Control box 30 ... Lower whetstone raising / lowering mechanism 33 ... Lower quill 34 ... Z-axis control motor 35 ... Z-axis feed screw 36 ... Nut 37 ... Bearing house 38 ... Bearing 40 ... Holding frame 41 ... Bolt 42 ... Hanging member 42a Key part 43 Lifter 43a Claw part 43b Guide hole 4
3c ... space 44 ... guide shaft 45 ... hydraulic cylinder 45a ... rod 45b ... barrel 45c ... piston 46a, 46b ... oil feed pipe 47 ... support rod 47a ... support part 47b ... end part 48 ... guide member 49 ... tension coil spring 50 ... Release shaft 51 ... Arm member 51a ... Elongated hole 52 ... Arm drive motor 52a ... Rotating shaft 53 ... Support table drive motor 53a ... Rotation shaft 54 ... Transport mechanism 54a ... Work clamping section 56 ... Work support table 57 ... Hydraulic cylinder 57a ... Rod 57b Barrel 57c Piston 58a, 58b Oil feed pipe 59 Pump 60 Control unit 61 Detection unit 62 Four-way switching valve 102 Work 102a Center hole 103 Drive rollers 104, 105 Guide rollers 106, 107 ... Whetstone 108 ... Strain area 109 ... Grinding area 110 ... Strain grinding area

Continuing from the front page (72) Inventor Tomoyuki Kawazu 1 Shinmeicho, Yokosuka City, Kanagawa Prefecture Inside the Heiwa Toyama Technical Center Co., Ltd. Reference) 3C016 AA01 BA02 CB06 CB11 CD01 CE05 3C034 AA08 AA13 BB22 BB75 BB84 3C043 BC06 CC04 DD05

Claims (11)

[Claims] 1. A grinding device for rotating a disk-shaped workpiece having a circular hole at its center while supporting it by a support mechanism, and grinding a plane of the workpiece by a rotating grindstone. The support mechanism may be arranged such that a roller is arranged in at least a hole provided in the workpiece, a roller is also arranged on the outer periphery of the workpiece, and the workpiece is sandwiched and supported by the roller. Features grinding equipment. 2. The method according to claim 1, wherein a plurality of the support mechanisms are provided on a rotatable work support table, and can be indexed at least at two positions, ie, a work grinding side facing the grindstone and a work mounting side opposite to the grinding wheel. The grinding device according to claim 1, wherein 3. The workrest according to claim 1, further comprising a work rest supported by the support mechanism and configured to hold a portion of the workpiece during grinding that is not supported by the grindstone under a static pressure. Grinding equipment. 4. The grinding apparatus according to claim 3, wherein the work rest is provided on a work support table provided with the support mechanism, the work rest corresponding to the support mechanism. 5. The work rest has a fluid ejection hole,
The grinding device according to claim 3 or 4, wherein a fluid is ejected from the fluid ejection hole to hold the workpiece from both upper and lower surfaces or only the lower surface under a static pressure. 6. The work rest, wherein the ejection pressure is changed so that the ejection pressure of the fluid in a later stage of grinding is higher than the ejection pressure of the fluid in an earlier stage of grinding the workpiece. The grinding device according to claim 5, wherein 7. The work rest, which holds a workpiece from both upper and lower surfaces under static pressure, and wherein the work rest on the upper surface side of the workpiece is provided to be vertically movable by its own weight. The grinding device according to claim 3 or 4. 8. The apparatus according to claim 1, wherein a plurality of the support mechanisms are provided around the grindstone by distributing an outer peripheral direction of the grindstone, and a plurality of workpieces can be ground at the same time.
The grinding device according to any one of the above. 9. A method of holding a workpiece in a thin plate shape by holding a workpiece by holding a workpiece under static pressure by sandwiching the workpiece with a jig having a fluid ejection hole and ejecting a fluid from the fluid ejection hole. A method for holding an object to be processed, characterized in that the pressure of jetting the fluid is changed during grinding. 10. A method of sandwiching a thin plate-shaped workpiece by a jig having a fluid ejection hole and ejecting a fluid from the fluid ejection hole to hold the workpiece under a static pressure. A method for holding a workpiece, wherein a fluid ejection pressure in a later stage of grinding is higher than a fluid ejection pressure in an earlier stage of grinding. 11. The apparatus according to claim 9, wherein the jig sandwiches a thin plate-shaped workpiece from both upper and lower surfaces, and the jig on the upper surface can be moved up and down by its own weight during processing. The method of holding the workpiece.