KR20130006303A - Method for grinding thin sheet-like workpiece and double-end surface grinder - Google Patents

Abstract

PURPOSE: A thin sheet-type workpiece grinding method and a double-sided surface grinder are provided to prevent the grinding accuracy of workpieces by damping the influence of external force delivered to a carrier ring because the carrier ring is supported by a static pressure carrier guide. CONSTITUTION: A thin sheet-type workpiece grinding method is as follows. Thin sheet-type workpieces mounted on a carrier(4) are supported by a pair of static pressure pads in a noncontact state. While the workpieces are rotated by the carrier, both sides of the workpieces are ground by a pair of grinding stones(3). Static pressure carrier guides(61,6b) are mounted in a peripheral direction. A carrier ring(5) has the outer peripheral surface(12) shaped like a cylindrical surface. The static pressure carrier guides are fixed or floated.

Description

METHOD FOR GRINDING THIN SHEET-LIKE WORKPIECE AND DOUBLE-END SURFACE GRINDER}

TECHNICAL FIELD This invention relates to the grinding method of the thin-shaped workpiece | work used for grinding thin-shaped workpiece | works, such as a silicon wafer, and a double head planar grinder.

When grinding thin-shaped workpieces, such as a silicon wafer, using a horizontal double-headed planar grinding machine, the left-right side which rotates about the horizontal axis while rotating the workpiece supported by the non-contact positive pressure by the pair of left-right positive-pressure pad around the center Grinding to a finish thickness determined by a pair of grinding grindstones.

The support system for rotatably supporting the work includes a direct contact support system (Patent Documents 1 and 2) for directly contacting and supporting the outer periphery of the work, and a carrier support system for supporting the work through a carrier and a carrier ring (Patent Document 3). ), And a direct contact support system includes a roller support system (Patent Document 1) and a belt support system (Patent Document 2).

The roller support method (patent document 1) supports the outer periphery of a disk-shaped workpiece | work rotatably by the some support roller in a circumferential direction, and makes it rotate | rotate a workpiece | work around a center by any one of the support rollers. . The belt support method (patent document 2) supports the outer periphery of the disk-shaped work in a circumferential direction with two sets of support belts, and rotates the work around the center by the support belts. have.

Carrier support system (patent document 3) mounts a workpiece | work to the mounting hole of the thin plate-shaped carrier with which the outer periphery was fixed to the carrier ring, and has a carrier ring by the several support roller arrange | positioned substantially equally in the outer periphery. The contact gears are held in contact with each other, and the drive gears engaged with the ring gears on the inner circumferential side of the carrier ring rotate the work around the center via the carrier ring and the carrier.

Japanese Patent Application Laid-open No. Hei 10-175144 Japanese Patent Application Laid-open No. Hei 10-156681 Japanese Patent Application Laid-Open No. 2005-205528

In the conventional direct contact support method, the outer periphery of the work is directly supported by the support roller or the support belt, and the work is rotated by the support roller or the support belt. There is a problem that I cannot.

On the other hand, the carrier support system uses a thin plate-shaped carrier whose outer periphery is fixed to the carrier ring, and drives and rotates the carrier ring supported by the outer periphery support roller while rotating the workpiece into the mounting hole. Compared to the supporting method, there is an advantage that the thin work can be ground with high accuracy. However, the conventional carrier support method employs the following contact support method by which the carrier ring is contact-supported by a plurality of support rollers arranged approximately equally on the outer circumference thereof.

That is, conventionally, since a plurality of support rollers are in contact support so as to cover the guide ring, the vibration of each support roller is transmitted to the carrier ring to be synthesized, and there is a problem that the rotational accuracy of the work is deteriorated by the combination. Moreover, when there is a defect in the attachment accuracy of the support shaft of a support roller, especially the parallelism with respect to the rotation center of a carrier ring, there exists a problem that a force other than rotation is transmitted to a carrier ring, and a carrier ring and a work | work incline.

In addition, the support roller may be formed by molding a resin material such as high hardness urethane and finishing it by machining so that the carrier ring is hardly damaged and the carrier ring can be reliably supported without slipping. Since the support roller is made of resin, there are the following problems. That is, it is difficult to stably obtain the circularity required for the support roller, and the quality of the support roller is easily deteriorated with time, and further, the support roller is easily worn. .

In view of such a conventional problem, the present invention can reduce the influence of the external force applied to the carrier ring, thereby improving the grinding precision of the work, and maintaining good grinding precision over a long period of time without causing problems such as friction. It is an object of the present invention to provide a method for grinding a thin plate-shaped workpiece and a double head grinder.

In the grinding method of the thin-shaped workpiece | work which concerns on this invention, the said thin-shaped workpiece | work mounted on a carrier is positively supported non-contactedly by a pair of positive pressure pad, and rotates the said workpiece through the said carrier, The said workpiece | work is carried out by a pair of grinding grindstones. When grinding both surfaces of the carrier, the carrier ring of the outer circumference of the carrier is statically supported in a non-contact manner by a plurality of static pressure carrier guides in the circumferential direction.

The double head planar grinding machine according to the present invention is a non-contact static pressure support of a thin plate-shaped workpiece mounted on a carrier by a pair of positive pressure pads, and is rotated on both sides of the workpiece by a pair of grinding grindstones while rotating the workpiece through the carrier. A two-sided planar grinding machine for grinding the die, comprising: a plurality of positive pressure carrier guides in the circumferential direction for statically supporting the carrier rings of the outer circumference of the carrier in a non-contact manner.

The carrier ring has an outer circumferential surface having a cylindrical surface shape, and the positive pressure carrier guides may be disposed approximately equally in close proximity to the outer circumferential surface. The positive pressure carrier guide may be fixed. It may be. In addition, the positive pressure carrier guide may be floatable.

Plot the positive pressure carrier guide by a floating axis approximately parallel to the rotation center of the carrier ring, and float the positive pressure pocket for supplying a constant pressure fluid to each of the positive pressure carrier guides with an outer circumferential surface of the carrier ring. The carrier ring may be provided substantially symmetrically in the rotational direction of the carrier ring.

A support arm pivotally supported by a pivot approximately parallel to the center of rotation of the carrier ring, the support arm movably supporting at least a portion of the constant pressure carrier guide relative to the carrier ring, and the support arm being pivotally supported. Drive means for rotating the circumference and stopper means for stopping the support arm at a predetermined position may be provided.

The static pressure carrier guide may be changed to a fixed state and a floating state that floats around a floating axis that is approximately parallel with the center of rotation of the carrier ring.

Three or more said positive pressure carrier guides arrange | positioned substantially equally on the outer periphery of the said carrier ring, and among these three or more positive pressure carrier guides, the position of the at least 1 constant pressure carrier guide is adjusted to the substantially radial direction of the said carrier ring. And the gap adjusting means for adjusting the gap between the positive pressure surfaces of the three or more positive pressure carrier guides and the outer circumferential surface of the carrier ring.

According to the present invention, since the carrier ring is statically supported by the positive pressure carrier guide, the influence of the external force applied to the carrier ring can be reduced, the grinding precision of the work can be improved, and problems such as friction and the like do not occur. There is an advantage that good grinding precision can be maintained over.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic side view of a lateral double head planar grinding machine showing one embodiment of the present invention.
2 is a schematic cross-sectional view thereof.
3 is an enlarged side view of the main part thereof.
Fig. 4 is an enlarged cross sectional view of the constant pressure carrier guide support on the upper side thereof;
5 is a sectional view of the fixed state of the hydrostatic carrier guide.
6 is a cross-sectional view taken along the line XX of FIG. 3.
7 is a cross-sectional view of the hydrostatic carrier guide.
8 is a bottom view of the hydrostatic carrier guide.
9 is a constant pressure circuit diagram of the constant pressure carrier guide.
10 is a cross-sectional view taken along the line YY of FIG. 3.
11 is a cross-sectional view of a floating state of the hydrostatic carrier guide.
It is a figure which shows the measurement result of the roundness of a carrier ring.
It is a figure which shows the measurement result of the outer periphery shake of a carrier ring in the conventional contact support system.
It is a figure which shows the measurement result of the outer periphery shake of a carrier ring in the non-contact support system of this invention.

EMBODIMENT OF THE INVENTION Hereinafter, each embodiment of this invention is described in detail based on drawing. The figure illustrates a lateral double head planar grinding machine employing the present invention. As shown in Figs. 1 and 2, the lateral double head planar grinder is arranged opposite to each other on the left and right, and a pair of left and right static pressure pads 1 for statically supporting the thin-shaped workpiece W non-contact, and each static pressure pad ( Corresponding to the notch 2 of 1), the left and right sides of the workpiece W supported by the static pressure pad 1 to be rotatably disposed around the grindstone axis in the left and right direction and moved in the axial direction of the cutting shaft are ground. Supports a pair of left and right grinding grindstones 3, a carrier 4 for rotating the mounted work W around the axis of the cutting shaft in a state held by the static pressure pad 1, and an outer periphery of the carrier 4 And a plurality of constant pressure carrier guides 6a and 6b which are arranged approximately equally on the outer circumference of the carrier ring 5 and which support the carrier ring 5 so as to be able to rotate in a non-contact manner from the outer circumference. have.

Each of the static pressure pads 1 is disposed at opposite end sides of the pair of left and right movable bases 8 that are movable in the axial direction of the cutting shaft, and is disposed between a forward position for holding the work W and a retreat position for retreating from the work W. FIG. The workpiece W is movable in the cutting axis direction, and the workpiece W is supported in a non-contact manner by a constant pressure fluid such as a constant pressure water supplied to the static pressure surface side facing the workpiece W at the forward position.

The carrier 4 is a thin plate-shaped disc that is thinner than the finishing dimension of the work W, and has a mounting hole 9 in which the work W is detachably mounted substantially concentrically. As shown in FIGS. 1 to 4, the carrier 4 is fixed to the carrier ring 5 arranged substantially concentrically on the outer circumference thereof, and is fixed within the carrier ring 5, and the outer circumference of the carrier 4 is defined by the carrier ring ( It is supported by the press ring 10 pressed to the 5) side. The carrier ring 5 has an outer circumferential surface 12 formed in the shape of a cylindrical surface substantially concentric with respect to the rotation center of the carrier 4, and end surfaces on both sides of the axial direction in the outer circumferential side of the positive pressure surface of the positive pressure pad 1 are formed. Opposite the gap with the edge part 11. The carrier means 7 is comprised by the carrier 4, the carrier ring, and the push ring 10, and the workpiece | work W enters and exits with this carrier means 7 integrally.

Moreover, although the thickness is small and the ceramic material, such as alumina, which is easy to raise roundness is used for the carrier ring 5, metal, such as stainless steel, may be sufficient. A ring gear 13 is provided on the inner circumference of the pressing ring 10, and the carrier means including the carrier 4 and the carrier ring 5 by the drive gear 14 engaged with the ring gear 13 ( 7) is rotationally driven.

Each static pressure carrier guide 6a, 6b is mounted on the opposite end side opposite to the carrier 4 of one movable base 8, and three or more are arranged approximately equally in the circumferential direction on the outer periphery of the carrier ring 5, have. For example, in this embodiment, four static pressure carrier guides 6a and 6b are arrange | positioned at about four times, and each of the positive pressure carrier guides 6a and 6b is floating, as shown to FIG. 3, FIG. 4, FIG. It is pivotally attached to the movable base 8 via the shafts 15a and 15b, and is movably attached to the fixed state and the floating state via the fixing means 16a and 16b and the restricting means 17a and 17b.

In each of the constant pressure carrier guides 6a and 6b, as shown in Figs. 7 and 8, the floating axes 15a and 15b are approximately at the center of the rotational direction of the carrier ring 5 (hereinafter simply referred to as the rotational direction). The axial hole 20 which penetrates is formed, and the positive pressure which opposes the two pin holes 21 arrange | positioned at the both sides of the axial hole 20, and the outer peripheral surface 12 of the carrier ring 5 with a small clearance gap. The surface 22, two positive pressure pockets 23 provided on the positive pressure surface 22 side, and a release groove 24 disposed between the two positive pressure pockets 23 are formed. The floating shafts 15a and 15b, the pin holes 21 and the shaft holes 20 are approximately parallel to the rotation axis and the cutting axis of the carrier ring 5, and the pin holes 21 rotate about the shaft hole 20. It is arrange | positioned substantially symmetrically on both sides of a direction.

The positive pressure surface 22 of each of the positive pressure carrier guides 6a and 6b is formed in an arc shape along the outer circumferential surface 12 of the carrier ring 5, and has a small gap between the outer circumferential surface 12 of the carrier ring 5. (For example, about 10 micrometers-about 30 micrometers), and it faces the radial direction. The positive pressure pocket 23 is for supplying a positive pressure fluid such as constant pressure water between the positive pressure surface 22 of the positive pressure carrier guides 6a and 6b and the outer circumferential surface 12 of the carrier ring 5, and the positive pressure surface 22. It is comprised by the recessed part recessed in the rotation direction, and long in a rotation direction, and is arrange | positioned substantially symmetrically on both sides of a rotation direction with respect to the floating shaft 15a, 15b and the axial hole 20. As shown in FIG. Each of the constant pressure pockets 23 is connected to the supply source 29 of the constant pressure fluid from the internal communication hole 25 via the flexible hose 26 on the side opposite to the constant pressure surface 22 and the like.

Of each of the positive pressure carrier guides 6a and 6b, the two positive pressure carrier guides 6a and 6b which face each other in the radial direction of the carrier ring 5 are positive pressure via the same circuit 27 as shown in FIG. It is connected to the supply source 29 of a fluid. In addition, each circuit 27 is provided with a pressure regulating valve 30 and a flow meter 31, whereby the pressure and the flow rate are managed.

The upper two static pressure carrier guides 6a are mounted to the support arms 34 pivotably attached to the movable base 8 by the pivot 33, as shown in FIGS. 3, 4 and 6. When the carrier means 7 is attached or detached, the support arm 34 is swung around the pivot 33 by the drive means 19 to move the upper static pressure carrier guide 6a in the perspective direction of the carrier ring 5. It is supposed to move to. The pivot 33 is approximately parallel with the floating axis 15a.

On one end of the support arm 34, a positive pressure carrier guide 6a is mounted in the receiving portion 35, and a cylinder 36 constituting the drive means 19 is connected to the other end. As shown in FIGS. 4 and 6, the housing portion 35 is provided between the side walls 35a and 35b of the support arm 34 in the radial direction of the carrier ring 5, and the accommodation portion ( The positive pressure carrier guide 6a is accommodated in the positive pressure carrier guide 6a by a floating shaft 15a penetrating through the side walls 35a and 35b on both sides of the accommodating portion 35 and inserted into the support arm 34. 6a) is pivotally supported. As shown in Figs. 3 and 6, the static pressure carrier guide 6a in the receiving portion 35 can be fixed to the support arm 34 at an appropriate angle by the fixing means 16a and the fixing means 16a. When it is released, it is possible to float within the floating range regulated by the restricting means 17a.

The fixing means 16a has a fixing pin 39 press-fitted into one pin hole 21 of the positive pressure carrier guide 6a, and a pin hole 38b into which the fixing pin 39 is inserted and detached, and has a support arm 34. It has a fixing bracket 38 detachably mounted to the side of. The fixing bracket 38 is pivotally attached to the support arm 34 by a fixing bolt 40 on the base side, and is screwed to the support arm 34 through the long hole 38a of the fixing bracket. The angle adjustment is possible around the fixing bolt 40 by the adjustment bolt 41. The pin hole 38b is formed at the tip end of the fixing bracket 38, and the fixing pin 39 is detachably fitted to the pin hole 38b. The restricting means 17a is constituted by the other pin hole 21 of the positive pressure carrier guide 6a and the restricting pin 42 penetrated through the receiving portion 35 and inserted into the pin hole 21. A gap corresponding to the floating range is formed between the pin 42 and the pin hole 21.

The cylinder 36 is interposed between the connecting pin 44 of the support arm 34 and the pivot support pin 45 of the movable base 8, and swings the support arm 34 around the pivot 33 to provide a positive pressure carrier. The guide 6a is moved with respect to the carrier ring 5 in the perspective direction (approximately the radial direction). On one end side of the support arm 34, a stopper means 47 for stopping the support arm 34 at a fixed position is provided.

As shown in Figs. 3 and 6, the stopper means 47 includes a contact portion 48 fixed to the movable base 8 and a screw-type stopper screwably adjustable to one end of the support arm 34 ( 49, and by adjusting the stopper 49, the space | interval between the positive pressure surfaces 22 of the positive pressure carrier guides 6a and 6b of the radial direction both sides of the carrier ring 5 changes, and the both positive pressure carrier guides The gap can be adjusted so that the carrier ring 5 is located approximately in the center between 6a and 6b. Therefore, the stopper means 47 also serves as a gap adjusting means for adjusting the gap between the positive pressure surface 22 of the positive pressure carrier guide 6a and the outer circumferential surface 12 of the carrier ring 5.

The lower two static pressure carrier guides 6b are fastening means 16b including a floating shaft 15b and a fixing bracket 50 as shown in Figs. 3, 5, 10 and 11 (Fig. 3, FIG. 5, and FIG. 10), and it is mounted so that change is possible in the fixed state and the floating state via the restricting means 17b (refer FIG. 11).

The floating shaft 15b is fixed to the movable base 8. The fixing bracket 50 is mounted so that one side in the longitudinal direction can be inverted front and rear with respect to the floating shaft 15b and the angle can be adjusted around the floating shaft 15b, and the fixing hole 53 is provided on the other end side. A larger diameter floating recess 54 is formed than the hole 53. The positive pressure carrier guide 6b is pivotally supported by the floating shaft 15b, and the coupling pin 55 is press-fitted into one pin hole 21. The amount of protrusion of the engaging pin 55 toward the fixing bracket 50 side is such that it does not engage the fixing hole 53 when the floating recess 54 is directed toward the positive pressure carrier guide 6b.

The fixing means 16b at the time of fixing the static pressure carrier guide 6b is made by the pin hole 21 of the engaging pin 55 and the fixing bracket 50, as shown to FIG. 3, FIG. 5, FIG. The positive pressure carrier guide 6b is fixed by inserting the engaging pin 55 into the pin hole 21.

Moreover, the restricting means 17b which regulates the floating range of the positive pressure carrier guide 6b is comprised by the coupling pin 55 and the floating recess 54 of the fixing bracket 50, as shown in FIG. When the coupling pin 55 enters the floating recess 54, the gap between the two pins corresponds to the floating range of the positive pressure carrier guide 6b.

At one end of the fixing bracket 50, two split type fixing portions 56 for fixing the base of the floating shaft 15b and fastening bolts 57 for fastening the fixing portions 56 are provided and fixed. The bracket 50 is angle adjustable with respect to the floating axis 15b. In addition, the fixing hole 53 and the floating recess 54 are formed long in the longitudinal direction of the fixing bracket 50 so that the fixing bracket 50 can be angled about the floating axis 15b.

In the grinding of the workpiece W, the workpiece W mounted on the carrier 4 is statically supported from the left and right sides by a pair of positive pressure pads 1 in a non-contact manner, and approximately 4 on the outer circumference of the carrier ring 5. A hydrostatic fluid is supplied from the hydrostatic pockets 23 of the hydrostatic carrier guides 6a, 6b arranged in equal distribution to the outer circumferential surface 12 of the carrier ring 5, and the hydrostatic fluid is supplied by the hydrostatic carrier guides 6a, 6b. Statically supports the carrier ring 5 non-contactly through it, and drives the carrier ring 5 through the ring gear 13 by the drive gear 14 and rotates the work W mounted on the carrier 4. It rotates around an axis and grinds both surfaces of the workpiece | work W with a pair of grinding grindstones 3 until it reaches a predetermined finishing dimension.

In this way, the carrier ring 5 can be positively supported in a non-contact manner by the positive pressure carrier guides 6a and 6b of the outer periphery. That is, between the outer peripheral surface 12 of the carrier ring 5, there is a static pressure fluid supplied from each of the constant pressure carrier guides 6a and 6b, and each of the constant pressure carrier guides 6a and 6b carries a carrier through the constant pressure fluid. The ring 5 can be statically supported non-contacted from the outer peripheral side. On the other hand, between the both end surfaces of the carrier ring 5, there exists a static pressure fluid supplied from each static pressure pad 1 similarly to the conventional one, and each static pressure pad 1 can support static pressure non-contactedly through a static pressure fluid.

For this reason, both the outer circumference and the both end surfaces of the carrier ring 5 are statically supported in a non-contact manner, and the carrier ring 5 during the grinding cycle as compared with the conventional contact supporting method of supporting the carrier ring 5 by a guide roller. The external force exerted on the workpiece | work W through the carrier 4 from the back becomes small, and the rotation precision (mainly outer periphery shake) of the workpiece | work W can be improved. Therefore, the grinding precision of the workpiece | work W can be improved.

In addition, since each of the positive pressure carrier guides 6a and 6b supports the carrier ring 5 to be rotatably fixed in a non-contact manner through a positive pressure fluid, problems such as abrasion due to contact between members as in the case of the contact support method. Can be maintained semi-permanently with good rotation accuracy. This can prevent deterioration of the grinding accuracy of the work W due to wear, increase in the number of maintenance steps, generation of consumable costs, and the like.

Moreover, among each of the static pressure carrier guides 6a and 6b arrange | positioned at approximately 4 times the outer periphery of the carrier ring 5, the positive pressure carrier guides 6a and 6b arrange | positioned at the both sides of the radial direction of the carrier ring 5 are FIG. As shown in FIG. 6, since the pressure and flow rate of the hydrostatic fluid are sufficiently connected to the same circuit 27, the positive pressure surface 22 of the hydrostatic carrier guides 6a and 6b and the outer circumferential surface 12 of the carrier ring 5 are shown. When the gap between the?) Fluctuates, a force for uniformizing the pressure in the same circuit 27 acts, and the carrier ring 5 is intended to maintain a stable position, so that stable rotational accuracy can be obtained.

That is, when the pressure balance of the pair of static pressure carrier guides 6a and 6b which opposes by some cause falls, for example, when the clearance gap between the lower positive pressure carrier guide 6b and the carrier ring 5 becomes narrow, the static pressure The pressure in the positive pressure pocket 23 of the carrier guide 6b rises. On the other hand, the clearance between the upper positive pressure carrier guide 6a and the carrier ring 5 becomes wide, and the pressure in the positive pressure pocket 23 of the positive pressure carrier guide 6a falls. Accordingly, according to the pressure difference between the positive pressure pockets 23 of the both positive pressure carrier guides 6a and 6b, the carrier ring 5 moves so that the gap between the both positive pressure carrier guides 6a and 6b is equal to a stable position. Will be maintained.

The outer circumferential surface 12 of the carrier ring 5 is a cylindrical surface that is substantially concentric with respect to the center of rotation of the carrier 4, and has a shape without a groove or the like in which the pressure of the hydrostatic fluid is released, and the outer circumferential surface of the carrier ring 5 ( Since the positive pressure surfaces 22 of the positive pressure carrier guides 6a and 6b are close to each other with a small gap, the carrier ring 5 can be stably supported by the positive pressure fluid, and the stable stability of the carrier ring 5 is achieved. Rotational accuracy can be obtained. In addition, the positive pressure surface 22 of each of the constant pressure carrier guides 6a and 6b has two positive pressure pockets 23 in the rotational direction of the carrier ring 5, and these pockets are formed by the release grooves 24 in the middle thereof. Since it divides into two, each positive pressure carrier guide 6a, 6b can balance the pressure of the positive pressure fluid in the both sides of the rotation direction of the carrier ring 5 independently.

When the carrier means 7 is attached or detached, the support arm 34 is swinged by the cylinder 36 in the direction of arrow a of FIG. 3 around the pivot 33 as shown by the double-dotted line in FIG. Static pressure carrier guides 6a are spaced apart in the radial direction of the carrier ring 5. Moreover, after putting the carrier ring 5 in the fixed position, the support arm 34 is rotated by the cylinder 36 in the opposite direction of the arrow a around the pivot 33. When the positive pressure surface 22 of the upper positive pressure carrier guide 6a and the outer circumferential surface 12 of the carrier ring 5 become a predetermined gap, the stopper 49 contacts the contact portion 48 to support the support arm 34. Regulate the meeting of).

Thus, by driving the support arm 34 by the cylinder 36 and moving the upper positive pressure carrier guide 6a, the pair of positive pressure carrier guides 6a arrange | positioned at the both sides of the radial direction of the carrier ring 5, Since the space | interval between 6b) changes, the entry | exit of the carrier ring 5 can be made easy and the automation can be aimed at easily.

Further, by adjusting the position where the screw stopper 49 of the stopper means 47 contacts the contact portion 48, the positive pressure surface 22 of each of the positive pressure carrier guides 6a and 6b and the outer peripheral surface of the carrier ring 5 ( The gap with 12) can be arbitrarily adjusted. That is, by adjusting the stopper 49, the position of the support arm 34 when the stopper 47 contacts the contact portion 48 changes, and the positive pressure carrier guide 6a on both sides in the radial direction of the carrier ring 5 is changed. , The interval between the positive pressure surfaces 22 of 6b) changes. And when a static pressure fluid is supplied to the outer periphery of the carrier ring 5 from the positive pressure carrier guides 6a and 6b of the radial direction both sides of the carrier ring 5, the carrier is substantially centered between both positive pressure carrier guides 6a and 6b. The ring 5 is located, and the space | interval of the outer peripheral surface 12 of the carrier ring 5 and the positive pressure surface 22 of the positive pressure carrier guides 6a and 6b of both sides substantially coincides. Therefore, according to the space | interval between the positive pressure surfaces 22 of the positive pressure carrier guides 6a and 6b of the radial direction both sides of the carrier ring 5, the positive pressure surface 22 and the carrier ring of each of the positive pressure carrier guides 6a and 6b. The interval with the outer peripheral surface 12 of (5) can be adjusted.

Each of the static pressure carrier guides 6a and 6b can be changed into a fixed state and a floating state, and can be appropriately classified and used by changing the order as necessary. For example, in the case where the roundness of the carrier ring 5 is high and the positive pressure support of the carrier ring 5 can be reliably supported, the respective constant pressure carrier guides 6a and 6b are fixed and the roundness of the carrier ring 5 is maintained. In the low case, each of the static pressure carrier guides 6a and 6b can be in a floating state. In addition, the lower two positive pressure carrier guides 6b may be fixed, and the upper two positive pressure carrier guides 6a may be in a floating state.

3 and 6 show a state in which the respective static pressure carrier guides 6a and 6b are fixed. When fixing the upper positive pressure carrier guide 6a, as shown in FIGS. 3, 5, 6, and 10, the fixing pin 39 of the positive pressure carrier guide 6a is fixed to the pin of the fixing bracket 38. It is inserted into the hole 38b, and the fixing bracket 38 is pivotally attached to the support arm 34 with the fixing bolt 40. As shown in FIG. When the fixing bracket 38 is rotated in the range of the long hole 38a around the fixing bolt 40 in this state, the positive pressure carrier guide 6a rotates around the floating shaft 15a, and the floating shaft 15a Since the gap between the positive pressure surface 22 of the positive pressure carrier guide 6a and the outer circumferential surface 12 of the carrier ring 5 changes on both sides of the position, the gap becomes approximately equal on both sides of the floating shaft 15a. The fixing bolt 41 may be tightened and fixed at.

In addition, since the adjustment allowance at the time of fixing the positive pressure carrier guide 6a is normally in the clearance gap with the regulation pin 42 of the pin hole 21, the regulation pin 42 penetrates into the pin hole 21. One state is good. In addition, the magnitude of the gap between the positive pressure surface 22 of the positive pressure carrier guide 6a and the outer circumferential surface 12 of the carrier ring 5 is appropriately adjusted by the stopper means 47.

When fixing the lower static pressure carrier guide 6b, as shown in FIGS. 5 and 10, the engaging pin 55 is fixed to the fixing hole 53 between the static pressure carrier guide 6b and the fixing bracket 50. Of the fixing bracket 50 so that the clearance between the positive pressure surface 22 of the positive pressure carrier guide 6b and the outer circumferential surface 12 of the carrier ring 5 is approximately equal on both sides of the floating shaft 15b. After the angle is adjusted by turning around the floating shaft 15b, the fastening bolts 57 are fastened to fix the fixing bracket 50 to the floating shaft 15b. As a result, the lower positive pressure carrier guide 6b is fixed.

Even in the case where the respective static pressure carrier guides 6a and 6b are fixed in this manner, there are two static pressure pockets 23 on the positive pressure surface 22 of each of the positive pressure carrier guides 6a and 6b, respectively. Since the static pressure fluid is supplied to the outer circumferential surface 12 of the carrier ring 5, the carrier ring 5 can be statically supported through the static pressure fluid. In addition, since each of the static pressure carrier guides 6a and 6b is fixed, the carrier ring 5 can be prevented from shaking to reliably support the carrier ring 5.

In the case where the upper static pressure carrier guide 6a is in a floating state, when the fixing bracket 38 is removed, the fixing pin 39 of the positive pressure carrier guide 6a is moved from the pin hole 38b of the fixing bracket 38. Because of the deviation, the fixing of the positive pressure carrier guide 6a by the fixing means 16a can be released. Thereby, the positive pressure carrier guide 6a can be floated around the floating axis 15a in the clearance gap between the regulation pin 42 and the pin hole 21. As shown in FIG.

When the lower static pressure carrier guide 6b is in a floating state, as shown in FIG. 11, the fixing bracket 50 is inverted to float the positive pressure carrier guide 6b within the range of the restricting means 17b. Mount it as much as possible. First, the positive pressure carrier guide 6b is removed from the floating shaft 15b, and the fixing bracket 50 is reversed from the front and rear to be mounted on the floating shaft 15b. Next, the positive pressure carrier guide 6b is covered with the floating shaft 15b, and the coupling pin 55 is coupled to the floating recess 54 of the fixing bracket 50.

Then, the fixing bracket 50 is moved on both sides of the floating shaft 15b so that the clearance between the positive pressure surface 22 of the positive pressure carrier guide 6b and the outer circumferential surface 12 of the carrier ring 5 becomes approximately equal. It adjusts to the circumference 15b, and fixes it with the fastening bolt 57. Thereby, the positive pressure carrier guide 6b can be floated around the floating axis 15b in the range of the clearance between the coupling pin 55 and the floating recess 54. As shown in FIG.

After allowing each of the positive pressure carrier guides 6a and 6b to be floated in this manner, a constant pressure fluid is supplied to the outer circumferential surface 12 of the carrier ring 5 from each of the positive pressure pockets 23 of the respective positive pressure carrier guides 6a and 6b. The carrier ring 5 can be statically supported via the static pressure fluid. In addition, when a gap occurs between the positive pressure surface 22 of the positive pressure carrier guides 6a and 6b and the outer peripheral surface 12 of the carrier ring 5 on both sides of the floating shafts 15a and 15b, the floating axis 15a and The hydrostatic carrier guides 6a and 6b float around the floating axes 15a and 15b so that the gaps on both sides of 15b) approximately coincide. Thus, contact between the positive pressure carrier guides 6a and 6b and the carrier ring 5 can be prevented in advance. In addition, since there are regulating means 17a and 17b for regulating the floating range of the positive pressure carrier guides 6a and 6b, it is possible to prevent unstable fluctuations around the floating axes 15a and 15b of the positive pressure carrier guides 6a and 6b. Can be.

In addition to using each of the static pressure carrier guides 6a and 6b in a fixed state or in a floating state, for example, two lower static pressure carrier guides 6b on the lower side are fixed, and the upper two mounted on the support arms 34 The positive pressure carrier guide 6a may be used to be floatable around the floating axis 15a. In this case, while making attachment and detachment of the carrier ring 5 easy, the clearance gap between the positive pressure surface 22 of each positive pressure carrier guide 6a, 6b and the outer peripheral surface 12 of the carrier ring 5 is made small, The carrier ring 5 can be stably supported statically.

That is, when attaching the upper positive pressure carrier guide 6a to the support arm 34 which rotates around the pivot 33, when fixing this constant pressure carrier guide 6a to the support arm 34, accumulation of an error etc. Thereby, there exists a possibility that the positive pressure carrier guide 6a may contact the carrier ring 5, and it becomes difficult to make the clearance gap between the positive pressure carrier guides 6a and 6b and the carrier ring 5 small. However, by floatingly mounting the positive pressure carrier guide 6a with respect to the support arm 34, the positive pressure surface 22 of each of the positive pressure carrier guides 6a and 6b and the outer peripheral surface 12 of the carrier ring 5 are fixed. While the gap is small, the contact with the carrier ring 5 can be prevented by floating the upper positive pressure carrier guide 6a.

In addition, using the carrier ring 5 made of ceramic, the non-contact support method of the present invention and the contact support method by the conventional support roller were verified. In the non-contact support method of the present invention, the conventional contact support method is used. In comparison, the outer periphery of the carrier ring 5 could be suppressed to about 1/5. 12 shows the measurement result of the roundness of the carrier ring 5. FIG. 13 shows the measurement result of the outer circumference of each carrier ring 5 in the case of the conventional contact support method, and in the case of the non-contact support method of the present invention.

As the carrier ring 5, as shown in FIG. 12, the carrier ring in each of the conventional contact support method and the non-contact support method of the present invention is made of a ceramic material having an outer circumferential roundness of about 5 µm (actual value 4.5 µm). The outer periphery shake of (5) was measured. In the conventional contact supporting method, the measured value of the outer circumferential shake is about 15 mu m as shown in FIG. 13, and when the outer circumferential roundness of the carrier ring 5 is subtracted (about 5 mu m), the outer circumferential shake is about 10 It becomes micrometer. On the other hand, the shake measurement value in the case of the non-contact support method is about 7 μm, as shown in FIG. 14, and when the outer circumference roundness (about 5 μm) of the carrier ring 5 is subtracted from this, the outer periphery shake is about 2 μm. do.

Therefore, in the non-contact supporting method of the present invention, the outer periphery of the carrier ring 5 can be suppressed to about 1/5 as compared with the conventional contact supporting method. Accordingly, the rotational accuracy of the carrier ring 5 is transmitted directly to the work W, which is in contact with its inner circumference through the carrier 4, and is fixed between the pair of grinding grindstones 3 during the grinding cycle. It acts on the grinding point of) and immediately affects the grinding of the work W. However, by adopting the non-contact support method of the present invention, the influence of the outer circumferential shaking of the carrier ring 5 can be reduced, and the work W A stable grinding precision of) can be obtained.

As mentioned above, although embodiment of this invention was described in detail, this invention is not limited to this embodiment, A various change is possible in the range which does not deviate from the meaning of this invention. For example, in the embodiment, each of the positive pressure carrier guides 6a and 6b can be changed into a fixed state and a floating state, but all of the positive pressure carrier guides 6a and 6b may be fixed or floating, and a plurality of lower The positive pressure carrier guide 6b may be fixed, and the plurality of upper positive pressure carrier guides 6a may be floating.

The positive pressure carrier guides 6a and 6b are preferably arranged approximately equally on the outer periphery of the carrier ring 5, but as long as the positive pressure carrier guides 6a and 6b can positively support the carrier ring 5. It does not need to be arranged approximately equally. In addition, when the positive pressure carrier guides 6a and 6b are arrange | positioned substantially equally, it is good that there are three or more positive pressure carrier guides 6a and 6b. And when there are three static pressure carrier guides 6a and 6b, the two positive pressure carrier guides 6b are arrange | positioned at the lower side, for example, and the one positive pressure carrier guide 6a of the upper side is radial direction of the carrier ring 5, for example. It may be installed to be movable.

When the positive pressure pocket 23 is provided on the positive pressure surfaces 22 of the positive pressure carrier guides 6a and 6b in a substantially symmetrical rotational direction with respect to the floating shafts 15a and 15b, as illustrated in the embodiment, in the rotational direction It may be arranged in two divisions, and one constant pressure pocket 23 long in the rotational direction may be provided in a continuous manner. The drive means 19 which drives the support arm 34 may be comprised by the motor other than the cylinder 36, and may drive the support arm 34 via a screw shaft or a gear by the motor.

When moving the positive pressure carrier guides 6a and 6b in the perspective direction with respect to the carrier ring 5, the guide base of the substantially radial direction of the carrier ring 5 is attached to the movable base 8, and according to the guide mechanism The positive pressure carrier guides 6a and 6b may be provided so as to be movable. Moreover, in embodiment, the stopper means 47 which stops the support arm 34 in a fixed position, the positive pressure surface 22 of the positive pressure carrier guides 6a, 6b, and the outer peripheral surface 12 of the carrier ring 5 are shown. Although the gap adjusting means for adjusting the gap is also used, both of them may be provided separately.

All the constant pressure carrier guides 6a, 6b may be connected to the source 29 of the constant pressure fluid via the same circuit 27, and each of the constant pressure carrier guides 6a, 6b may be individually connected through an independent pressure control circuit. The supply source 29 may be connected. Moreover, in embodiment, although the horizontal type grinder was illustrated, it can implement also in a vertical type. In addition, as long as the workpiece | work W is a thin plate shape, what kind of thing may be sufficient as it.

1: static pressure pad 3: grinding grindstone
4: carrier 5: carrier ring
6a, 6b: static pressure carrier guide 12: outer peripheral surface
15a, 15b: floating axis 16a, 16b: fixing means
17a, 17b: regulating means 19: driving means
21: pin hole 22: positive pressure surface
29: Source 33: Pivot
34: support arm 47: stopper means (gap adjusting means)
W: Walk

Claims (9)

When grinding both surfaces of the said workpiece by a pair of grinding grindstones while supporting a thin plate-shaped workpiece mounted on a carrier in a non-contact manner by a pair of positive pressure pads and rotating the workpiece through the carrier, A method of grinding a thin workpiece, characterized in that the carrier ring of the outer periphery of the carrier is supported in a non-contact manner by a plurality of static pressure carrier guides in the circumferential direction. In a double-sided planar grinding machine for grinding a plate-shaped workpiece mounted on a carrier in a non-contact manner by a pair of static pressure pads, and grinding both sides of the workpiece by a pair of grinding grindstones while rotating the workpiece through the carrier, And a plurality of positive pressure carrier guides in the circumferential direction for positively supporting the carrier rings of the outer circumference of the carrier in a non-contact manner. The double head grinding machine according to claim 2, wherein the carrier ring has a cylindrical outer circumferential surface, and the positive pressure carrier guides are arranged in an equal multiple of the outer circumferential surface. The two-sided flat grinding machine according to claim 2 or 3, wherein the constant pressure carrier guide is fixed. The double head grinding machine according to claim 2 or 3, wherein the hydrostatic carrier guide is floatable. The static pressure carrier guide is pivotally supported by a floating axis parallel to the rotation center of the carrier ring, and the positive pressure is applied to each of the positive pressure carrier guides with an outer peripheral surface of the carrier ring. And a hydrostatic pocket for supplying a fluid symmetrically in the rotational direction of the carrier ring with respect to the floating axis. The support according to claim 2 or 3, wherein the support is pivotally supported by a pivot parallel to the center of rotation of the carrier ring and supports at least some of the static pressure carrier guides in a distant direction relative to the carrier ring. An arm, a drive means for rotating the support arm around the pivot, and a stopper means for stopping the support arm at a predetermined position. The double head grinding machine according to claim 2 or 3, wherein the constant pressure carrier guide is changeable to a fixed state and to a floating state floating around a floating axis parallel to the center of rotation of the carrier ring. The static pressure carrier guide according to claim 2 or 3, further comprising three or more positive pressure carrier guides arranged equally on the outer circumference of the carrier ring, wherein the position of at least one of the three static pressure carrier guides is determined. And a gap adjusting means for adjusting the gap between the positive pressure surfaces of the three or more static pressure carrier guides and the outer circumferential surface of the carrier ring by adjusting in the radial direction of the carrier ring.

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