Double-sided polishing machine

Abstract

To provide a both-side polishing device that can surely detect tucking of a thin work-piece.SOLUTION: A both-side polishing device, which polishes both sides of a work-piece, by holding the work-piece at a plurality of holding holes of a plurality of carriers arranged on a lower surface plate comprising a polishing cloth and rotating the lower surface plate and an upper surface plate comprising a polishing cloth opposing to the lower surface plate, is provided with a CCD camera 51 that photographs the work-piece arranged on the holding holes and detecting means 71 that detects deviations of the work-piece with respect to the holding holes on the basis of photographed data obtained with the CCD camera 51, which enables deviations of the work-piece to be detected on the basis of the photographed data.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present invention relates to a double-side polishing machine that processes the surface of a workpiece held by a carrier by rotating upper and lower polishing plates. [Background technology]

[0002] As shown in Figs. 18 to 20, a conventional machine of this type includes an upper surface plate 101, a lower surface plate 102 that is provided coaxially opposite to the upper surface plate 101, a sun gear 103 and an internal gear 104 that are coaxially arranged between the upper surface plate 101 and the lower surface plate 102, and a carrier 107 that has a holding hole 106 for a workpiece 105 that rotates and revolves while being interposed between the sun gear 103 and the internal gear 104, and a ring-shaped workpiece 105 that is provided on the underside of the upper surface plate 101. A double-sided polishing apparatus (e.g., Patent Documents 1 and 2) has a lower polishing tool (such as a polishing cloth or grindstone) having a shape similar to that of the lower polishing tool, and an annular upper polishing tool is provided on the upper surface of the lower surface plate 102 opposite the lower polishing tool, and the upper surface plate 101, lower surface plate 102, sun gear 103, and internal gear 104 are rotated by respective drive motors 108, 109, 110, and 111, and the upper surface plate 101 is provided with a fluid outlet 112 consisting of a nozzle opening on the underside.

[0003] In the above-described conventional double-sided polishing apparatus, when the upper surface plate 101, the lower surface plate 102, the sun gear 103, and the internal gear 104 are rotated by the drive motors 108, 109, 110, and 111, the carrier 107 undergoes planetary motion in which it revolves around the sun gear 103 while rotating on its own axis. Furthermore, an abrasive liquid such as slurry is supplied from the fluid outlet 112, and both sides of the workpiece 105, such as a magnetic disk substrate, held by the carrier 107 are polished by the upper surface plate 101 and the lower surface plate 102.

[0004] Furthermore, it is also possible to grind the internal gear 104 by driving the other driving motors 108, 109, and 110 while the internal gear 104 is fixed, without driving the driving motor 111 for the internal gear 104, or by driving the other driving motors 108, 109, and 110 while the internal gear 104 is fixed, without providing the driving motor 111 for the internal gear 104.

[0005] Furthermore, as shown in Figure 20, in order to rotate the upper surface plate 101, the above-mentioned double-sided polishing apparatus is provided with an upper surface plate drive shaft 113 having a vertical center of rotation on a head (not shown) arranged above the lower surface plate 102 so as to be freely movable up and down, and the upper surface plate 101 is fixed to a drive plate connected to this upper surface plate drive shaft 113 by a so-called universal joint type connecting mechanism 114, and the connecting mechanism 114 allows freedom in the tilt of the upper surface plate 101.

[0006] The upper surface plate 101 is connected to a cylinder shaft (not shown) installed on the top of the device via a universal joint 115 or a spherical bearing so that its angle can be freely changed. This allows the upper surface plate 101 to be aligned with the lower surface plate 102 even if it is slightly tilted during polishing, and also allows a uniform load to be applied from the upper surface plate 101 at all times even if the thickness of the workpiece 105 varies.

[0007] There is also a polishing apparatus (e.g., Patent Document 3) in which a drive shaft is provided above an upper surface plate, and this drive shaft is configured to be able to rise and fall and rotate, and the upper surface plate is connected to the lower end of the drive shaft by a connecting mechanism, so that the upper surface plate is driven to rise and fall and also rotated by the rotation of the drive shaft.

[0008] In the double-sided polishing machine described above, a safety device has conventionally been attached to prevent the workpiece from getting pinched and to prevent polishing from starting when the workpiece is not properly set in the carrier. This safety device has a sensor that measures the distance between the upper and lower platens when the upper platen is lowered from its elevated standby position to the polishing position where it contacts the workpiece at the start of polishing. The upper platen is connected to a rod of a sub-cylinder located at the center above the upper platen, and the height position of the rod is detected by a position sensor (for example, Patent Document 4).

[0009] As shown in Figure 20, workpiece pinching occurs when the workpiece 105 is not set correctly in the mounting hole of the carrier 107, with part of the workpiece 105 protruding outside the mounting hole, and part of the workpiece 105 overlaps the carrier 107, resulting in the workpiece being pinched between the upper and lower surface plates 101 and 102.

[0010] However, in today's double-sided polishing processes, workpieces (hard disks) are becoming thinner, and there is a demand for processing thin workpieces (for example, thicknesses of 0.5 mm and 0.381 mm).

[0011] In contrast, in the double-sided polishing apparatus of Patent Document 4, if a thinned workpiece becomes pinched near the center of the platen, the rod acting as the pressure axis may not be displaced or may be so small that it cannot be detected. Also, when a workpiece is pinched at one point on the outer periphery of the lower platen, the displacement of the center of the upper platen is slight, and if there is no displacement of the upper platen due to the workpiece being wedged in the polishing pad, it may not be possible to detect that the disk has become pinched.

[0012] In contrast, there is a polishing machine (e.g., Patent Document 5) that detects the height of the outer periphery of the upper surface plate. The workpiece is loaded into a holding hole in a carrier and is then clamped between the upper and lower surface plates to polish the workpiece. The polishing machine has an abnormal loading detector that detects abnormal positions in the vertical direction of the upper surface plate member when the workpiece is abnormally loaded. The detector is located above the outer periphery of the upper surface plate member.

[0013] In the polishing machine of Patent Document 5, a detector detects the displacement of the outer periphery of the upper surface plate member, so it can detect pinching on the outer periphery of the upper surface plate member, compared to the polishing machine of Patent Document 4, which detects the displacement of the center of the upper surface plate.

[0014] Incidentally, just like the upper platen which can be raised and lowered, the lower platen is also height adjustable, and after the height position of the lower platen is fixed, the workpiece is loaded onto the lower platen, polished, and removed once, and the workpiece is polished a predetermined number of times (for example, several hundred times). However, during multiple polishing operations, the lower platen may drop slightly. Also, an abrasive cloth is attached to the top surface of the lower platen, and if the abrasive cloth becomes clogged, a brush is applied to prevent clogging, which can cause the abrasive cloth to wear out and the height of the lower platen to drop.

[0015] For this reason, the polishing machine of Patent Document 5, in which the detector is mounted on a fixed base separate from the upper polishing plate and located around the upper polishing plate, has the problem that the measurement accuracy decreases before the specified number of polishings is completed, and to prevent this, it is necessary to frequently reset the height of the lower polishing plate. [Prior art documents] [Patent documents]

[0016] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-7748 [Patent Document 2] Japanese Patent Application Laid-Open No. 2010-179398 [Patent Document 3] Japanese Patent Application Laid-Open No. 2000-271843 [Patent Document 4] Publication number 4-48925 [Patent Document 5] Japanese Patent Application Publication No. 2-106269 Summary of the Invention [Problem to be solved by the invention]

[0017] SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a double-side polishing machine that can reliably detect the pinching of a thin workpiece. [Means for solving the problem]

[0018] In order to achieve the above object, the invention of claim 1 provides a double-side polishing machine that holds a workpiece on a plurality of holders of a plurality of carriers arranged on a lower surface plate equipped with a lower polishing tool, and polishes both sides of the workpiece by rotating the lower surface plate and an upper surface plate facing the lower surface plate equipped with an upper polishing tool, the machine comprising: an imaging means for imaging the workpiece arranged on the holders; and a detection means for detecting a deviation of the workpiece relative to the holders using image data obtained by the imaging means. The system includes a carry-in table having carry-in side holding portions for the plurality of workpieces corresponding to the plurality of holding portions, and a supply / carry-out device that supplies the plurality of workpieces arranged on the carry-in side holding portion to the holding portions of the lower surface plate, the supply / carry-out device is provided with the imaging means, and the detection means detects the position of the center hole of the workpiece, the supply / carry-out device includes a movable body having a plurality of supply units, and the supply unit is provided with a plurality of holding devices corresponding to the center holes of the plurality of workpieces held in the holding portions, and the imaging means is provided at the center of these plurality of holding devices, the holding devices hold the workpieces, and the workpieces are transported by movement of the movable body, and the imaging range of the imaging means is set so as to include the center holes of all of the workpieces on one of the carriers. It is characterized by:

[0019] Claim 2 The invention of ,before The detection means ,before The image obtained by the imaging means The central hole of the workpiece placed on the loading side holding section The deviation of the workpiece relative to the loading side holder is detected based on the image data.

[0020] Claim 3 The invention is characterized in that it comprises a displacement sensor that detects the amount of vertical displacement on the outer periphery of the upper surface plate, and an abnormality detection means that detects abnormalities from the amount of displacement of the upper surface plate obtained by the displacement sensor, and the displacement sensor is provided in a non-rotating part of an upper surface plate drive device that is provided above the upper surface plate and drives the upper surface plate to rotate.

[0021] Claim 4 The invention is characterized in that it comprises a displacement sensor that detects the amount of vertical displacement on the outer periphery of the upper surface plate, and an abnormality detection means that detects abnormalities from the amount of displacement of the upper surface plate obtained by the displacement sensor, and the displacement sensor is provided on a rotating body that is provided above the upper surface plate and rotates together with the upper surface plate. [Effects of the Invention]

[0022] According to the invention of claim 1, the deviation of the workpiece can be detected by the image data.

[0023] In addition, Claim 1 According to the invention, deviations of a plurality of workpieces can be detected simultaneously.

[0024] In addition, Claim 1 According to the invention, there is no need to capture an image of the outer periphery of the workpiece, and deviation of the workpiece can be detected within a relatively narrow imaging range. Furthermore, images can be taken at a position closer to the workpiece than when the outer periphery of the workpiece is used as the reference, and the center holes of multiple workpieces can be photographed simultaneously without moving the supply unit laterally during imaging.

[0025] Claim 2 According to the invention, the deviation of the workpiece relative to the carry-in side holder can be detected by the imaging data obtained by the imaging means, and the deviation of the workpiece placed on the carry-in side holder of the carry-in table can be detected. 。

[0026] Claim 3 According to the invention, after the workpiece is clamped between the upper and lower platens, the clamping of the workpiece can be detected, and by detecting the displacement of the outer periphery of the upper platen, the clamping of a thin workpiece on the outer periphery of the upper platen can be detected.

[0027] Claim 4 According to the invention, after the workpiece is sandwiched between the upper and lower surface plates, it is possible to detect whether the workpiece is sandwiched, and by detecting the displacement of the outer periphery of the upper surface plate, it is possible to detect whether a thin workpiece is sandwiched on the outer periphery of the upper surface plate. Moreover, the displacement of the upper surface plate can be detected by the displacement sensor even during polishing when the upper surface plate is rotating. [Brief explanation of the drawings]

[0028] [Figure 1] 1 is a plan view of a main part of a lower surface plate showing a first embodiment of the present invention. [Figure 2] FIG. 10 is a vertical cross-sectional view of the main part of the device. [Figure 3] FIG. [Figure 4]FIG. [Figure 5] FIG. 10 is a front view showing the mounting state of the imaging means. [Figure 6] FIG. 10 is a plan view showing the mounting state of the imaging means. [Figure 7] FIG. [Figure 8] FIG. [Figure 9] FIG. [Figure 10] FIG. 10 is a front view of an apparatus showing a second embodiment of the present invention. [Figure 11] FIG. [Figure 12] FIG. [Figure 13] FIG. 10 is a front view of an apparatus showing a third embodiment of the present invention. [Figure 14] FIG. [Figure 15] 1 is a plan view of a supply device showing a first embodiment of the present invention. [Figure 16] FIG. [Figure 17] FIG. 10 is a cross-sectional view of the loading side holding section on which the workpiece is placed. [Figure 18] FIG. 1 is a perspective view showing a conventional technique. [Figure 19] FIG. [Figure 20] FIG. DETAILED DESCRIPTION OF THE INVENTION

[0029] Preferred embodiments of the present invention will be described with reference to the accompanying drawings. [Example]

[0030] Figures 1 to 9 and Figures 15 to 17 described below.1 shows a first embodiment of the present invention, in which a double-sided polishing machine 1 is provided with a lower polishing platen 3 having a polishing cloth 2 as a lower polishing tool attached to its upper surface 3U, and an upper polishing platen 5 coaxial with the lower platen 3 and having a polishing cloth 4 as an upper polishing tool attached to its lower surface 5K.

[0031] As shown in FIG. 1 etc., a carrier 7 for holding a plurality of workpieces 6 is placed on the upper surface 3U of the lower surface plate 3. The carrier 7 has holding holes 8 formed therein as holding portions for holding the workpieces 6, and a plurality of teeth 9 are formed on the outer periphery 7A of the carrier 7. A plurality of carriers 7 are also arranged concentrically on the upper surface 3U of the lower surface plate 3, and each carrier 7 has holding holes 8 formed in a plurality of locations (five locations) to hold five workpieces 6. All of the carriers 7 have the same shape. An example of the workpieces 6 is a metal magnetic disk substrate.

[0032] A driving sun gear 11 that meshes with the teeth 9 of the carrier 7 is provided in the center of the upper surface 3U of the lower surface plate 3, and an internal gear 12 is provided concentrically on the outer periphery 3A of the lower surface plate 3. The teeth 9 of the carrier 7 mesh with pin-shaped teeth 12H provided on the inner periphery 19 of this internal gear 12, and the teeth 9 of the carrier 7 mesh with pin-shaped teeth 11H provided on the outer periphery 18 of the sun gear 11. In FIG. 2, 11J is the central axis of rotation of the sun gear 11.

[0033] The sun gear 11 and the internal gear 12 have different rotation speeds, and rotate at different speeds. As a result, when the lower surface plate 3, the upper surface plate 5, the sun gear 11, and the internal gear 12 are rotated by the lower surface plate drive motor 13, the upper surface plate drive motor 14, the sun gear drive motor 15, and the internal gear drive motor 16, the carrier 7 rotates on its own axis while causing a planetary motion in which it revolves around the sun gear 11, and both the upper and lower surfaces of the workpiece 6 held by the carrier 7 are polished.

[0034] It is preferable to use a method of driving the four drive motors 13, 14, 15, and 16 due to the pressure applied to the tooth portion 9 of the carrier 7, etc. However, it is also possible to perform polishing by driving the other drive motors 13, 14, and 15 without driving the internal gear drive motor 16 and keeping the internal gear 12 fixed (not rotating), or by driving the other drive motors 13, 14, and 15 while keeping the internal gear 12 fixed, without providing the internal gear drive motor 16 in the double-sided polishing apparatus 1.

[0035] Furthermore, polishing can be performed by driving the other drive motors 13, 14, and 16 while the sun gear 11 is fixed (not rotating) without driving the sun gear drive motor 15, or by driving the other drive motors 13, 14, and 16 while the sun gear 11 is fixed (not rotating) without providing the sun gear drive motor 15 in the double-sided polishing apparatus 1.

[0036] The lower surface plate 3 and the upper surface plate 5 have the same outer diameter, and the motors 13, 14, 15, and 16 are formed by servo motors or inverter motors, and these motors 13, 14, 15, and 16 are integrally provided with fixed position stop control means (not shown).

[0037] 3 and other figures, an upper surface plate drive device 21 is provided above the upper surface plate 5 to drive the upper surface plate 5 up and down and rotate it, and this drive device 21 is provided so as to be able to move up and down by an elevation drive device (not shown). A cylinder 23 is provided above a case body 22 of the drive device 21, and a rotary drive shaft 25 is moved up and down relative to the case body 22 by an extendable rod 24 of this cylinder 23. A rotation transmission sleeve (not shown) that rotates the rotary drive shaft 25 is provided inside the case body 22 and fitted onto the rotary drive shaft 25, and this rotation transmission sleeve is fixed in a height position relative to the case body 22 and is rotatable. The rotary drive shaft 25 is provided inside the rotation transmission sleeve so as to be able to move up and down, and the rotation of the rotation transmission sleeve is fitted onto the rotary drive shaft 25, so that the rotation of the rotation transmission sleeve is transmitted to the rotary drive shaft 25. The lower end of the rotary drive shaft 25 is inserted into a disk-shaped rotary fixing portion 27 that is integrally provided at the lower end of the rotation transmission sleeve. Therefore, the rotary drive shaft 25 moves up and down due to the extension and contraction of the extendable rod 24, and the upper surface plate drive motor 14 (Fig. 2) rotates the rotation transmission sleeve, causing the rotary drive shaft 25 to rotate together with the rotation transmission sleeve. The upper surface plate drive device 21 corresponds to the head described in the prior art.

[0038] A connecting mechanism 26 is provided at the lower end of the rotary drive shaft 25, and the upper surface plate 5 is connected to the lower part of this connecting mechanism 26. Therefore, the upper surface plate 5 is raised and lowered together with the drive unit 21 by the lifting drive device, the upper surface plate 5 is raised and lowered relative to the drive unit 21 by the extension and contraction of the extendable rod 24, and the upper surface plate 5 is rotated relative to the drive unit 21 by the upper surface plate drive motor 14.

[0039] The connecting mechanism 26 includes an upper connecting plate 32 disposed below the drive unit 21, with the lower end of the rotary drive shaft 25 fixed to the upper surface of the upper connecting plate 32, and the upper connecting plate 32 moves up and down together with the drive unit 21, moving up and down relative to the drive unit 21 by extension and contraction of the extendable rod 24, and rotating by rotation of the rotary drive shaft 25. During actual driving, the upper surface plate drive unit 21 is lowered by the lifting drive unit until the upper surface plate 5 approaches the lower surface plate 3, and then the rotary drive shaft 25 is lowered to close the upper and lower surface plates 5, 3. The lifting drive unit raises and lowers the upper surface plate drive unit 21 by means of a lifting drive motor and a ball screw on a main body column (not shown), etc. 3 is raised and lowered by the lifting drive device, and the upper limit of the lifting stroke by the lifting drive device is a height at which the upper surface plate 5 is about 500 mm away from the lower surface plate 3, allowing access for the movable body 43, and a lower limit is a height at which the upper surface plate 5 is about 1 to 5 mm from the lower surface plate 3. Then, from the height at which the upper surface plate 5 is about 1 to 5 mm from the lower surface plate 3, the upper surface plate 5 is lowered together with the rotation drive shaft 25 by the extendable rod 24.

[0040] The upper surface plate 5 is fixed to the upper connecting plate 32 via a universal joint or spherical bearing so that its angle can be freely changed. In this example, a universal joint 31 (Figure 4) is used, and the lower end of the rotary drive shaft 25 is fixed to the upper surface of the disk-shaped upper connecting plate 32 of this universal joint 31. The rotary drive shaft 25 transmits rotation to the universal joint 31, causing the upper surface plate 5 to rotate.

[0041] 4, the universal joint 31 has a pair of left and right upper blocks 33, 33 fixed at a distance from each other on the lower surface of the upper connecting plate 32, and a pair of left and right lower blocks 34, 34 fixed at a distance from each other on the upper surface of a lower connecting plate 35. A generally cross-shaped connecting body 36 connecting the upper blocks 33, 33 and the lower blocks 34, 34 has one-side connecting shafts 37, 37 rotatably connected to the upper blocks 33, 33 and another-side connecting shafts 38, 38 rotatably connected to the lower blocks 34, 34, and the one-side connecting shafts 37 and the other-side connecting shafts 38 are perpendicular to each other.

[0042] Therefore, as the upper blocks 33, 33 rotate relative to the one-side connecting shaft 37 and the lower blocks 34, 34 rotate relative to the other-side connecting shaft 38, the lower connecting plate 35 swings relative to the upper connecting plate 32, and the upper surface plate 5 is connected to this lower connecting plate 35. In this way, the upper connecting plate 32 is a member that fixes the blocks 33, 33, which allow the one-side connecting shafts 37, 37 to rotate, and the one-side connecting shafts 37, 37 are one connecting shafts of the connector 36.

[0043] As shown in Fig. 7, ten carriers 7 are arranged concentrically at equal intervals on the upper surface 3U of the lower surface plate 3. A supply / unloading device 41 (Fig. 5) for the workpieces 6 includes a moving body 43 having ten moving arms 42 arranged radially from its center. The supply / unloading device 41 also includes a supply unit 44 located directly above each carrier 7 above the lower surface plate 3, with the center 43S (Fig. 16) of the moving body 43 aligned with the center 3S of the lower surface plate 3. The moving body 43 moves up and down and laterally by a moving mechanism (not shown).

[0044] 5, 6, and 8, the supply unit 44 has a mounting bracket 46 for an imaging means attached to the lower end of a fixed shaft 45 that is attached to the tip of the moving arm 42. This mounting bracket 46 connects the upper parts of a pair of vertical frame parts 47, 47 that are arranged at a distance from each other via an upper frame part 48, and a disk-shaped mounting member 49 is provided on the lower part of the pair of vertical frame parts 47, 47. Five holding devices 50, the same number as the number of holding holes 8 (FIG. 1), are attached to this mounting member 49, corresponding to the center holes 6H of the workpieces 6 held in each holding hole 8.

[0045] The holding device 50 has a pair of open / close type opening / closing claws 50A, 50A, the outer peripheral surfaces of the lower ends of these opening / closing claws 50A, 50A are formed to follow the shape of the center hole 6H, and when not holding, the distance between the outer peripheral surfaces of the lower ends of the opening / closing claws 50A, 50A is smaller than the diameter of the center hole 6H, and when holding, the distance between the opening / closing claws 50A, 50A widens and the opening / closing claws 50A, 50A engage with the center hole 6H. In this way, the opening / closing claws 50A, 50A are open / close type.

[0046] A CCD camera 51, which is an imaging means, is provided inside the mounting bracket 46 facing downward, and is attached so that the center of a lens 52 of this camera 51 is positioned above the center of the carrier 7. Also, as shown in Fig. 5, a ring-shaped hood 53 is provided on the underside of the mounting member 49 below the lens 52 of the camera 51, and this hood 53 has an upper surface portion 53J and a cylindrical outer peripheral surface portion 53G, and a lower opening 53K (Fig. 5) is formed at the lower edge of the outer peripheral surface portion 53G.

[0047] A ring-shaped illumination means 55 is provided within the hood 53 so as to surround the tip of the CCD camera 51, and an LED is exemplified as the light source of this illumination means 54. Also provided in the hood 53 is a shutter device 56 that can open and close the lower opening 53K, and this shutter device 56 includes a shutter main body 57 that opens and closes the lower opening 53K, and a shutter drive unit (not shown) that drives the shutter main body 57 to open and close. The lower side of the CCD camera 51 is attached to the mounting member 49, and the upper side of the holding device 50 is also attached to the mounting member 49, with the lower part of the CCD camera 51 positioned above and away from the opening and closing claws 50A that are the lower part of the holding device 50.

[0048] 8, the imaging range 58 of the CCD camera 51 at the imaging position is set so that the center holes 6H of all the workpieces 6 on one carrier 7 are included, and this allows imaging to be performed at a position closer to the workpieces 6 than when the outer periphery of the workpieces 6 is used as the reference. Distortion occurring outside the imaging range 58 is corrected using a calibration chessboard / dot pattern or the like.

[0049] The double-side polishing machine 1 is provided with a detection means 61 (FIG. 9) that detects the deviation of the workpiece 6 from the holding holes 8 based on the image data obtained by the CCD camera 51. It is also provided with a center hole detection unit 62 that detects the position of the center hole 6H of the workpiece 6. This center hole detection unit 62 detects the position of the center hole 6H, for example, from the tread edge position, and detects the center position 6S (FIG. 8) of the center hole 6H from the position of the center hole 6H.

[0050] The double-sided polishing apparatus 1 includes a drive control unit 63 (FIG. 2), which controls the drive of the double-sided polishing apparatus 1. Specifically, the drive control unit 63 controls the rotation and elevation of the upper platen 5, and controls the drive motors 13, 14, 15, and 16 of the lower platen 3. The drive control unit 63 controls the drive so that the holding holes 8 are positioned at a preset supply / unloading position, and stores the center position 8S of the holding holes 8.

[0051] The detecting means 61 is provided with a deviation detecting section 64 that compares the center position 8S of the holding hole 8 at the supply and transport position with the center position 6S of the center hole 6H obtained by imaging with the CCD camera 51, and detects deviation of the center position 6S, and is provided with a notifying means 65 that notifies when the deviation exceeds a predetermined value. 6 The offset can be set to a value such that a part of the outer periphery of the polishing pad 2 overlaps the upper surface of the polishing cloth 2 on the lower surface plate 3.

[0052] The notification means 65 notifies the operator by sound or display of improper loading of the workpieces 6 into the holding holes 8, and this may prompt an operator to stop the double-sided polishing apparatus 1 or cause it to stop automatically, after which the carriers 7 are properly attached to the holding holes 8 by manual work or the like. The notification means 65 may also be provided with a carrier display means 66, which can also notify the operator of which of the multiple (10) carriers 7 has been improperly loaded with the workpieces 6.

[0053] For example, each supply unit 44 can be provided with a carrier display means 66 that lights up to indicate a filling defect. If the carrier display means 66 is a lighting display, the carrier display means 66 of the supply unit 44 in which a filling defect has occurred lights up, making it possible to determine in which carrier 7 the defective filling of the workpieces 6 has occurred. Alternatively, the carrier 7 may be provided with an identification display section such as a number or symbol, and the carrier display means 66, which is made up of a display or the like, may display the identification display section of the carrier 7 in which a filling defect has occurred.

[0054] Next, the operation of the above configuration will be described. With the upper surface plate 5 separated from the lower surface plate 3 by the upper surface plate drive device 21, the supply unit 44 of the supply / carry-out device 41 supplies the workpieces 6 to the holding holes 8 of the carrier 7 on the upper surface 3U of the lower surface plate 3. After all the workpieces 6 have been supplied, the supply unit 44 rises to an imaging position where the CCD camera 51 can capture an image of the imaging range 58 shown in Figure 8, and stops. This stopping position is the imaging position where the entire center hole 6H can be imaged without the opening / closing claw 50A hiding the center hole 6H.

[0055] The lower opening 53K is closed by the shutter body 57 except when imaging, and this prevents the abrasive liquid and the like from adhering to the lens 52 of the CCD camera 51.

[0056] The shutter body 57 is opened at the imaging position, and the illumination means 55 is turned on to illuminate the carrier 7, and an image is taken. The detection means 61 detects the deviation of the workpiece 6 from the holding hole 8 from the imaging data obtained from the CCD camera 51, and the improperly filled workpiece 6 can be set correctly in the holding hole 8 before the workpiece 6 is clamped between the upper and lower surface plates 5, 3. After the workpiece 6 is set correctly in this way, the upper surface plate 5 is lowered so that the lower surface of the upper surface plate 5 comes into contact with the upper surface of the workpiece 6, and the workpiece 6 is clamped between the upper and lower surface plates 5, 3.

[0057] Then, when the lower platen 3, upper platen 5, sun gear 11, and internal gear 12 are rotated by the lower platen drive motor 13, upper platen drive motor 14, sun gear drive motor 15, and internal gear drive motor 16, the carrier 7 rotates on its own axis while performing planetary motion in which it revolves around the sun gear 11.Furthermore, by supplying an abrasive such as slurry (not shown), both sides of the workpiece 6 held on the carrier 7 are polished by the polishing cloth 2 on the lower platen 3 and the polishing cloth 4 on the upper platen 5.

[0058] After double-side polishing of the workpieces 6 is completed, the upper surface plate 5 is raised slightly to separate from the lower surface plate 3, and a fluid such as compressed air or water is sprayed onto the upper surface of the workpieces 6 from a fluid outlet (not shown) consisting of a nozzle or the like, controlled by an on-off valve (not shown). After the upper surface plate 5 stops rotating, the fluid supply path is connected to the fluid outlet. The fluid outlets are arranged so that at least one fluid outlet faces each workpiece 6. The pressing force of the fluid presses the workpieces 6 and the carrier 7 toward the lower surface plate 3, and the workpieces 6 and carrier 7 are peeled off from the lower surface 5K of the upper surface plate 5 and remain on the lower surface plate 3.

[0059] Then, the workpiece 6 after polishing can be held and transported by the holding device 50 of the supply / carry-out device 41. Thereafter, a new workpiece 6 before polishing is placed on the lower surface plate 3 again and polished.

[0060] As described above, in this embodiment, in accordance with claim 1, the workpiece 6 is held in a plurality of holding holes 8 as holding portions of a plurality of carriers 7 arranged on a lower surface plate 3 having a polishing cloth 2 as a lower polishing tool, and both sides of the workpiece 6 are polished by rotating the lower surface plate 3 and the upper surface plate 5 facing the lower surface plate and having a polishing cloth 4 as an upper polishing tool. In this double-side polishing machine 1, the CCD camera 51 is an imaging means for imaging the workpiece 6 arranged in the holding holes 8, and the detection means 61 is for detecting a deviation of the workpiece 6 with respect to the holding holes 8 based on the image data obtained by the CCD camera 51. The apparatus includes a carry-in table 81 having a tray 83 as a carry-in holding section for a plurality of workpieces 6 corresponding to the plurality of holding holes 8, and a supply / carry-out device 41 that supplies the plurality of workpieces 6 arranged on the tray 83 to the holding holes 8 of the lower surface plate 3, a CCD camera 51 is provided on the supply / carry-out device 41, and a detection means 61 detects the position of the center hole 6H of the workpiece 6, the supply / carry-out device 41 includes a moving body 43 having a plurality of supply units 44, the supply unit 44 is provided with a plurality of holding devices 50 corresponding to the center holes 6H of the plurality of workpieces 6 held in the holding holes 8, and the CCD camera 51 is provided at the center of these plurality of holding devices 50, the holding device 50 holds the workpieces 6, and the workpieces 6 are transported by the movement of the moving body 43, and the imaging range 58 of the CCD camera 51 is set so as to include the center holes 6H of all of the workpieces 6 of one carrier 7. Therefore, the deviation of the workpiece 6 can be detected from the image data.

[0061] In this way, in this embodiment, claims 1 Correspondingly, the CCD camera 51 serving as the imaging means captures images of the plurality of workpieces 6, so that the deviations of the plurality of workpieces 6 can be detected simultaneously.

[0062] In this way, in this embodiment, claims 1 Correspondingly, the detecting means 61 detects the position of the central hole 6H of the workpiece 6, so there is no need to image the outer periphery of the workpiece 6, and the deviation of the workpiece 6 can be detected in a relatively narrow imaging range 58. Furthermore, the image can be captured at a position close to the workpiece 6, and the central holes 6H of a plurality of workpieces 6 can be captured simultaneously without moving the supply unit 44 laterally during the image capture.

[0063] As an effect of the embodiment, since the CCD camera 51 is arranged corresponding to each carrier 7 and at the center of the plurality of holding devices 50 arranged concentrically, the central holes 6H of the plurality of workpieces 6 can be photographed simultaneously without moving the supply unit 44 sideways. Also, the lower side of the CCD camera 51 is attached to the mounting member 49, and the upper side of the holding device 50 is attached to the mounting member 49.

[0064] In addition, a hood 53 is provided to cover the tip of the CCD camera 51, and a shutter device 56 is provided to open and close a lower opening 53K which is the opening of the hood 53, so that the abrasive liquid and the like can be prevented from adhering to the CCD camera 51.

[0065] In addition, the detection means 61 is equipped with a deviation detection unit 64 that compares the center position 8S of the holding hole 8 at the supply and transport position with the center position 6S of the center hole 6H obtained by imaging with the CCD camera 51 to detect deviation of the center position 6S, and is equipped with an alarm means 65 that issues an alarm when the deviation exceeds a predetermined value, so that improper filling of the carrier 7 into the holding hole 8 is notified by sound or display, and the workpiece 6 can be correctly attached to the holding hole 8 by manual operation, etc. [Example]

[0066] 10 to 12 show a second embodiment of the present invention, in which the same parts as those in the first embodiment are given the same reference numerals and detailed description thereof will be omitted. This embodiment is provided with an abnormality detection means 71 that detects the height position of the outer periphery of the upper surface of the upper surface of the upper surface plate 5 to detect abnormalities such as pinching of the workpiece 6.

[0067] The abnormality detection means 71 comprises a contact-type displacement sensor 72 as a displacement sensor, a control unit 73, and a signal line 74 that electrically connects the contact-type displacement sensor 72 and the control unit 73, and detects the amount of displacement in the vertical position of the upper surface plate 5 by bringing the tip of the rod-shaped movable part 72A of the contact-type displacement sensor 72 into contact with a measurement part 78 provided on the upper surface of the upper surface plate 5.

[0068] The abnormality detection means 71 includes a notification means 75 that detects and notifies when the amount of vertical displacement of the outer periphery of the upper surface plate 5 exceeds a predetermined value.

[0069] Furthermore, the control unit 73 detects the amount of displacement in the vertical direction of the upper surface plate 5 based on the detection signal indicating the amount of displacement output by the contact displacement sensor 72, and the control unit 73 detects the displacement by utilizing, for example, the phenomenon in which the inductance (magnetic induction coefficient) of the coil changes depending on the amount of displacement of the movable part 72A.

[0070] 10, a plurality of (eight) sensor mounting arms 76 are provided radially from the center of the case body 22 and at equal intervals in the circumferential direction on the lower side surface of the case body 22 of the upper surface plate drive device 21. The sensor mounting arms 76 are non-rotating parts that do not rotate with respect to the rotating upper surface plate 5. The sensor mounting arms 76 are attached to the lower side surface of the case body 22 near the upper surface plate 5.

[0071] The contact-type displacement sensor 72 is mounted on the tip of the mounting arm 76 with its movable part 72A facing downward, and a post 77 is provided on the upper surface of the upper surface plate 5 corresponding to the movable part 72A, and the upper surface of this post 77 is the part to be measured 78 with which the tip of the movable part 72A abuts. The movable part 72A is biased in the direction of abutting against the part to be measured 78.

[0072] Furthermore, as shown in FIG. 10, the movable part 72A can be fixed at a standby position away from the part to be measured 78, and at the standby position, the movable part 72A will not come into contact with the post 77 when the upper surface plate 5 rotates.

[0073] An example of a method for detecting pinching of the workpiece 6 by the abnormality detection means 71 will now be described. After the workpiece 6 is properly mounted on the carrier 7, the upper surface plate 5 is lowered to the polishing position (reference position) where polishing is actually performed, and is stopped at the fixed position by control, and the movable part 72A is brought into contact with the measured part 78, and the height position of the movable part 72A of each sensor 72 at this polishing position is stored as the reference position. Furthermore, during detection, it is preferable that the combination and planar position of the sensor 72 and the measured part 78 are also kept constant.

[0074] After polishing is completed, the upper surface plate driving device 21 rises and moves from above the lower surface plate 3, and then the workpiece 6 is loaded into the holding hole 8 by the supply / carry-out device 41 as described above, and any deviation of the workpiece 6 is detected from the image data captured by the CCD camera 51. In this example, the detection by the CCD camera 51 can be omitted.

[0075] After the workpiece 6 is supplied, the upper surface plate 5 is lowered and the workpiece 6 is sandwiched between the upper and lower surface plates 5, 3, which are positioned by control. From here, the movable part 72A is brought into contact with the part to be measured 78, and when the deviation between the height position of the part to be measured 78 measured by the movable part 72A of each sensor and the reference position exceeds a predetermined value, this is detected by the abnormality detection means 71 and is notified by the notification means 75.

[0076] When the notification means 75 notifies of pinching, the upper surface plate 5 is raised and the workpiece 6 in which the abnormal pinching has occurred can be properly attached to the holding hole 8, or the workpiece 6 can be replaced and attached to the holding hole 8.

[0077] In this way, the present embodiment provides the same functions and effects as the first embodiment.

[0078] In this embodiment, the claims 3Corresponding to this, the device is provided with a contact displacement sensor 72 which is a displacement sensor that detects the amount of displacement in the vertical direction on the outer periphery of the upper surface plate 5, and an abnormality detection means 71 which detects the abnormal pinching of a workpiece 6 from the amount of displacement of the upper surface plate 5 obtained by the contact displacement sensor 72, and the contact displacement sensor 72 is provided on a sensor mounting arm 76 which is a non-rotating part of the upper surface plate drive device 21 which is provided above the upper surface plate 5 and drives the upper surface plate 5 to rotate.Therefore, after the workpiece 6 is pinched between the upper and lower surface plates 5, 3, it is possible to detect the pinching of a thin workpiece 6 on the outer periphery of the upper surface plate 5 by detecting the displacement on the outer periphery of the upper surface plate 5.

[0079] As an effect of the embodiment, since the connecting mechanism 26 is equipped with a universal joint 31, when a workpiece 6 is sandwiched between the carriers 7 of the upper and lower surface plates 5 and 3, the outer periphery of the upper surface plate 5 tilts, making it easier to detect the pinch.

[0080] Furthermore, a plurality of sensor mounting arms 76 are radially arranged on the case body 22, which is the non-rotating part of the upper surface plate drive device 21 that is provided above the upper surface plate 5 and drives the upper surface plate 5 to rotate, and the contact displacement sensor 72 is provided at the tip side of the sensor mounting arm 76, which is the member for mounting the sensor. Therefore, the member for mounting the sensor does not become large, and the contact displacement sensor 72 can be arranged on the outer periphery of the upper surface plate 5.

[0081] Furthermore, since the contact-type displacement sensor 72 does not rotate and is electrically connected to the control unit 73 by the signal line 74, there is no need to provide the contact-type displacement sensor 72 with wireless communication means, making the contact-type displacement sensor 72 relatively inexpensive. [Example]

[0082] 13 and 14 show a third embodiment of the present invention, in which the same parts as those in the above-described embodiments are assigned the same reference numerals and detailed description thereof will be omitted. In this embodiment, the mounting arm 76 is attached to the upper connecting plate 32 of the universal joint 31 that rotates by the rotary drive shaft 25, and the contact displacement sensor 72 is provided at the tip of the mounting arm 76. Eight mounting arms 76 are provided radially from the center of the upper connecting plate 32.

[0083] In this example, a wireless communication means 74A is provided which electrically connects the contact displacement sensor 72 and the control unit 73. Note that the wireless communication means 74A may be any of short-range wireless communication such as Bluetooth (registered trademark), short-range wireless communication such as NFC, short-range wireless communication by wireless LAN such as Wifi (registered trademark), and other short-range wireless communication.

[0084] Furthermore, an attachment arm 76 is fixed to the upper connecting plate 32 of the universal joint 31 connected to the upper surface plate 5, and the contact displacement sensor 72 is fixed to this attachment arm 76. This makes it easy to align the contact displacement sensor 72 with the part to be measured 78 during manufacturing, and enables the contact displacement sensor 72 to detect the displacement of the upper surface plate 5 with high accuracy.

[0085] In this way, this embodiment provides the same functions and effects as the above-described embodiments.

[0086] In this embodiment, the claims 4 Corresponding to this, the device is provided with a contact displacement sensor 72 which is a displacement sensor that detects the amount of vertical displacement on the outer periphery of the upper surface plate 5, and an abnormality detection means 71 which detects the abnormal pinching of a workpiece 6 from the amount of displacement of the upper surface plate 5 obtained by the contact displacement sensor 72, and the contact displacement sensor 72 is provided on the upper connecting plate 32 which is a rotating body that is provided above the upper surface plate 5 and rotates together with the upper surface plate 5, so that pinching of the workpiece 6 can be detected after the workpiece 6 is pinched between the upper and lower surface plates 5, 3, and by detecting the displacement on the outer periphery of the upper surface plate 5, it can be detected that a thin workpiece 6 has been pinched on the outer periphery of the upper surface plate 5.

[0087] Furthermore, since the upper surface plate 5 on which the measured portion 78 is mounted and the contact displacement sensor 72 rotate integrally as an abnormality detection means 71, even during polishing while the upper surface plate 5 is rotating, the contact displacement sensor 72 detects the height position of the measured portion 78 and compares the height position of the measured portion 78 with the reference position. If the deviation between the measured height position of the measured portion 78 and the reference position exceeds a predetermined value, the alarm means 65 issues an alarm or stops polishing.

[0088] Furthermore, a plurality of mounting arms 76 are radially provided on the upper connecting plate 32, which is a rotating body that is provided above the upper surface plate 5 and rotates by the rotary drive shaft 25 that rotates the upper surface plate 5, and the contact displacement sensors 72 are provided at the tip ends of the mounting arms 76, so that the members for attaching the sensors do not become large and the contact displacement sensors 72 can be arranged on the outer periphery of the upper surface plate 5. Furthermore, by attaching the contact displacement sensors 72 by the mounting arms 76 to the upper connecting plate 32 that is provided integrally with the upper surface plate 5 via the universal joints 31, the contact displacement sensors 72 are provided integrally with the upper surface plate 5 together with the parts to be measured 78, so that the parts to be measured 78 and the contact displacement sensors 72 can be aligned with high precision during assembly, and the measurement precision of the contact displacement sensors 72 is also improved.

[0089] 15 to 17 show embodiments of the present invention. 1 In this example, the loading table 81 has a table body 81A that rotates, and the workpieces 6 before polishing are placed on a plurality of loading-side holding portions of the table body 81A by an automatic workpiece supply device 80 such as a robot arm, and the deviation of the workpieces 6 is detected by the detection means 61.

[0090] 15, the table main body 81A is provided with a disk-shaped workpiece loading section 82 corresponding to the carrier 7, and this workpiece loading section 82 is provided with trays 83 serving as loading-side holding sections corresponding to the holding holes 8, and a plurality of trays 83 are arranged at the same positions as the plurality of holding holes 8 of the upper surface plate 5. Then, unmachined workpieces 6 are placed on the workpiece loading section 82 of the loading table 81 in a positional relationship corresponding to the arrangement of each workpiece 6 held by the carrier 7 of the lower surface plate 3, and the holding devices 50 are also arranged in a positional relationship corresponding to the arrangement of each workpiece 6.

[0091] As shown in FIG. 17, the tray 83 has a cylindrical side wall portion 84 and a bottom surface portion 85 that closes the lower part of the side wall portion 84, and a circular opening 85K is formed in the center of the bottom surface portion 85.

[0092] The side wall portion 84 has an upper opening 84K provided with an upper tapered inner peripheral surface 84A that narrows downward, and a concentric inner peripheral surface 84B below this upper tapered inner peripheral surface 84A, and a lower tapered inner peripheral surface 84C that narrows downward is formed between this inner peripheral surface 84B and the upper surface of the bottom portion 85. The corner between the inner peripheral surface 84B and the lower tapered inner peripheral surface 84C is a mounting portion 84D for the workpiece 6.

[0093] As described above, the tray 83 has an upper tapered inner peripheral surface 84A that narrows downward, so even if the holding device 50 is released before the workpiece 6 is placed on the placement portion 84D and the outer edge of the workpiece 6 hits the upper tapered inner peripheral surface 84A, the workpiece 6 will be placed on the placement portion 84D due to its own weight. However, if the outer edge of the workpiece 6 gets caught on the upper tapered inner peripheral surface 84A and the workpiece 6 becomes tilted, there is a risk that the center position 6S of the workpiece 6 and the center position 83S of the tray 83 will be misaligned.

[0094] The drive control unit 63 (FIG. 2) controls the rotation drive of the rotation drive unit (not shown) of the carry-in table 81 so that the tray 83 is positioned at a preset carry-out position, and stores the center position 83S (FIG. 15) of the tray 83.

[0095] The supply device 80 supplies the unpolished workpieces 6 to each tray 83, and in this case, after the workpieces 6 have been supplied to all the trays 83, the drive control unit 63 controls the drive so that the trays 83 are positioned at the unloading position and stops them.

[0096] The detection section 64 of the detection means 61 compares the center position 83S of the tray 83 at the unloading position with the center position 6S of the central hole 6H obtained by image capture by the CCD camera 51, detects a deviation of the center position 6S, and if the deviation exceeds a predetermined value, this is notified by the notification means 65. The center position 83S of the tray 83 is the center position of the opening 85K.

[0097] As in the above embodiment, the notification means 65 notifies the operator by sound or display of improper loading of the carriers 7 onto the tray 83, which prompts the operator to stop the double-sided polishing apparatus 1 or may cause it to stop automatically. After the apparatus has stopped, the workpieces 6 are properly loaded onto the tray 83 by manual or other means. The notification means 65 may also be provided with a tray display means 67 (FIG. 9), which notifies the operator of which of the multiple (10) workpiece loading sections 82 the loading has occurred in. If the deviation between the center position 6S of the center hole 6H of the workpiece 6 and the center position 83S of the tray 83 exceeds a predetermined value, problems such as an inability to transport the workpieces are expected to occur.

[0098] This allows improperly filled workpieces 6 to be set correctly on the trays 83 before they are carried out. After the workpieces 6 have been set correctly in accordance with the trays 83 in this way, the supply and carry-out device 41 is lowered, all of the trays 83 are held by the holding device 50, the supply and carry-out device 41 is moved onto the lower surface plate 3, and the workpieces 6 are supplied by the supply unit 44 to the holding holes 8 of the carriers 7 on the upper surface 3U of the lower surface plate 3, and after the supply, the CCD camera 51 and the detection means 61 detect the deviation between the center position 6S and the center position 8S.

[0099] If the deviation is less than a predetermined value, the upper surface plate 5 is lowered, and further, on the condition that the abnormality detection means 71 does not detect any pinching, polishing is started.

[0100] In addition, if an abnormality detection means 71 is provided in which the upper surface plate 5 on which the measured portion 78 is provided and the contact displacement sensor 72 rotate integrally, the contact displacement sensor 72 can detect the height position of the measured portion 78 even during polishing while the upper surface plate 5 is rotating, and the height position of the measured portion 78 can be compared with the reference position, and an abnormality can be detected if the deviation between the measured height position of the measured portion 78 and the reference position exceeds a predetermined value.

[0101] In this way, this embodiment provides the same functions and effects as the above-described embodiments.

[0102] In this embodiment, the claims 2 In response to , Examination The output means 61 is , as an imaging means Obtained by CCD camera 51 The center hole 6H of the workpiece 6 placed on the tray 83, which is the carrying-in side holding portion, Since the deviation of the workpiece 6 relative to the tray 83 is detected by the imaging data, the deviation of the workpiece 6 relative to the tray 83 can be detected by the imaging data obtained by the CCD camera 51, and the deviation of the workpiece 6 placed on the tray 83 of the carry-in table 81 can be detected. do.

[0103] As an effect of the embodiment, the CCD camera 51 is provided as an imaging means for imaging the workpiece 6 placed in the holding hole 8, and the detection means 61 detects the deviation of the workpiece 6 from the holding hole 8 based on the imaging data obtained by the CCD camera 51, and the CCD camera 51 is provided on the supply unit 44 that transfers the workpiece 6, and the workpieces 6 before polishing on the tray 83 of the carry-in table 81 that are arranged in a positional relationship corresponding to the arrangement of each workpiece 6 held on the carrier 7 of the lower surface plate 3 are imaged by the CCD camera 51, and the presence or absence of deviation is detected by the detection means 71, and then the workpieces 6 before polishing that are correctly arranged on the tray 83 are transferred to the supply / carry-out device 4. 1 onto the lower platen 3, and the workpiece 6 is attached to the holding hole 8 by the supply unit 44, after which an image is taken by the CCD camera 51 and the presence or absence of misalignment of the workpiece 6 is detected by the detection means 61. Therefore, the workpiece 6 of the supply device 80, which is positioned in a positional relationship corresponding to the arrangement of the workpiece 6 on the lower platen 3, is transferred to the holding hole 8 of the lower platen 3 in the same positional relationship by the CCD camera 51 provided on the supply unit 44 that transfers the workpiece 6, and the misalignment of the workpiece 6 can be detected not only on the lower platen 3 but also on the supply device 80 using the CCD camera 51 provided on the supply unit 44.

[0104] In addition, since this method detects abnormalities such as pinching by the abnormality detection means 71 when the workpiece 6 is sandwiched between the upper and lower surface plates 5, 3 and closed, abnormalities can be detected not only by detecting misalignment using an image, but also from the displacement of the upper surface plate 5 using the contact displacement sensor 72 when the workpiece 6 is sandwiched between the upper and lower surface plates 5, 3 and closed.

[0105] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the present invention. For example, the present invention is applicable to workpieces other than magnetic disk substrates, such as semiconductor wafers and liquid crystal substrates. However, the present invention is particularly effective in terms of time when polishing magnetic disks, which require a shorter polishing time than semiconductor wafers. Although the embodiments illustrate contact-type displacement sensors, non-contact displacement sensors using ultrasonic waves or the like may also be used. Furthermore, various types of imaging means may be used, such as cameras and videos other than CCDs. Furthermore, the loading-side holding unit may be a mounting hole for mounting the workpiece, rather than a tray. Furthermore, while the embodiments illustrate sun gears and internal gears with pin-shaped teeth, involute-type gears may also be used. If an involute-type gear is used, the teeth of the carrier may also be involute. [Explanation of symbols]

[0106] 1 Double-sided polishing machine 2 Polishing cloth (lower polishing tool) 3 Lower surface plate 3S center 4 Polishing cloth (upper polishing tool) 5 Upper surface plate 6 Work 6H center hole 6S center position 7. Career 8 Holding hole (holding part) 8S center position 21 Upper surface plate drive unit 22 Case body (non-rotating part) 25 Rotating drive shaft 31 Universal joint 32 Upper connecting plate (rotating body) 41 Supply and unloading device 43 Mobile 44 Supply Unit 50 Holding device 51 CCD camera (imaging means) 58 Imaging range 61 Detection methods 71 Abnormality detection means 72 Contact type displacement sensor (displacement sensor) 81 Loading table 83 Tray (carry-in side holding section) 83S center position

Claims

1. A double-side polishing apparatus for polishing both sides of a workpiece by holding a workpiece on a plurality of holding portions of a plurality of carriers arranged on a lower surface plate having a lower polishing tool, and rotating the lower surface plate and an upper surface plate facing the lower surface plate and having an upper polishing tool, an imaging means for imaging the workpiece placed in the holder; a detection means for detecting a deviation of the workpiece relative to the holding portion based on the imaging data obtained by the imaging means; a carry-in table having a plurality of workpiece carry-in side holding portions corresponding to the plurality of holding portions; a supply and carry-out device that supplies the plurality of workpieces arranged in the carry-in side holding section to the holding section of the lower surface plate, The imaging means is provided in the supply / carry-out device, the detecting means detects the position of the center hole of the workpiece, the supply and carry-out device includes a moving body having a plurality of supply units; The supply unit is provided with a plurality of holding devices corresponding to the central holes of the plurality of workpieces held in the holding section, and the imaging means is provided at the center of the plurality of holding devices, the holding device holds the workpiece and transfers the workpiece by moving the moving body; A double-side polishing machine characterized in that the imaging range of the imaging means is set so as to include the center holes of all of the workpieces on one of the carriers.

2. A double-sided polishing apparatus as described in Claim 1, characterized in that the detection means detects the misalignment of the workpiece relative to the loading side holding portion based on the imaging data of the center hole of the workpiece placed on the loading side holding portion obtained by the imaging means.

3. a displacement sensor for detecting the amount of vertical displacement of the outer periphery of the upper surface plate; an abnormality detection means for detecting an abnormality based on the displacement amount of the upper surface plate obtained by the displacement sensor; 3. A double-side polishing machine according to claim 1, wherein the displacement sensor is provided in a non-rotating portion of an upper platen drive device that is provided above the upper platen and drives the upper platen to rotate.

4. a displacement sensor for detecting the amount of vertical displacement of the outer periphery of the upper surface plate; an abnormality detection means for detecting an abnormality based on the displacement amount of the upper surface plate obtained by the displacement sensor; 3. A double-side polishing apparatus according to claim 1, wherein the displacement sensor is provided on a rotating body that is disposed above the upper surface plate and rotates together with the upper surface plate.

Images