JPH01205972A - Polishing device - Google Patents

Abstract

PURPOSE:To feed a uniform and fresh abrasive at all times, stabilize a polishing amount and enhance machining accuracy by providing a tape feed means for supplying and travelling a tape having an abrasive between the machined plane of a rotating workpiece and an oscillating polishing tool. CONSTITUTION:A drive motor is actuated to turn a feed screw and cause the slide of a slide axis 32 toward a workpiece 1, thereby clamping a nose 38 fitted to an abrasive supply device 40 fixed to the said axis 32 between lap tapes 39 and causing the hitting of the nose 38 to the workpiece 1. Then, the workpiece 1 is turned with a drive motor 22 and another drive motor is to cause the lap tapes 39 to travel on tension in an approximately vertical direction along the curvature of the tip of the nose 38, and the abrasive on the lap tapes 39 polishes an area where the tip of the nos 38 and the workpiece 1 are in contact with each other. In this case, the nose 38 is oscillated with an oscillation device 201 and pressed to the workpiece 1 with a weight 33 by the predetermined pressing force.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a polishing device, and more particularly to a polishing device suitable for partially correcting and polishing the surface shape of a workpiece having an optical mirror surface, such as a lens or mold. [Conventional technology] In order to process a workpiece such as a lens into the designed surface shape with high precision and obtain a smooth optical mirror surface, the surface created by grinding etc. must be finished by uniform polishing. After shape measurement, a partial correction polishing process is required to polish the surface while removing local shape errors based on the measurement results. A conventional device used for this partial correction polishing process is shown in FIG. In this figure, 1 is a rotating work such as a lens, 2 is a felt attached to the tip of a spindle 4 rotated by a drive motor 3, and the spindle 4 is supported by a bracket 5 via a ball glaze holder. is attached to a slide shaft 6 that is movable in the direction of the workpiece 1. In the conventional apparatus, with the above configuration, the felt 2 coated with an abrasive material is pressed against the rotated work 1, and the felt 2 is rotated by the drive motor 3 to partially correct and polish the work 1. [Problems to be Solved by the Invention] However, in the conventional device as described above, since ball bearings are used to support the spindle 4, highly accurate rotation cannot be obtained, and as a result, the swinging of the felt 2 ( rotational shake)
There is a problem in that the area that contacts the processing surface of the workpiece 1 becomes larger, making it difficult to locally polish a minute area. Furthermore, since the portion of the felt 2 that contacts the workpiece 1 is always at the same position, there is a problem that the abrasive material applied to the felt 2 causes clogging and the amount of polishing of the workpiece 1 is unstable. In addition to the felt mentioned above, Bakelite 5 cast iron is used as a tool, and as an abrasive,
A mixture of diamond paste and grease or diamond oil (or *) has been used, but the problem is that the amount of polishing cannot be maintained constant because the abrasive materials are floating abrasive grains. SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, an object of the present invention is to provide a polishing device that can stabilize the amount of polishing for corrective polishing of minute parts and can provide polishing with higher precision and a better surface shape. do. Means for Solving Problem E] In order to achieve the above object, the present invention provides a pressure means for pressing an abrasive tool against a rotating workpiece processing surface with a constant pressure, and a pressurizing means for pressing an abrasive tool against a rotating workpiece processing surface, and The present invention is characterized by comprising a tape supply means for supplying and traveling an abrasive-attached tape to the polishing tool, and a swinging means for swinging the polishing tool. [Function] The present invention has a rotating workpiece machining surface and t! A tape with abrasive material is fed between the moving abrasive tool and the tape is oscillated by the abrasive tool and pressed against the machined surface of the workpiece with a constant pressure, so that a uniform new abrasive material is applied to the machined surface. The polishing amount is constantly supplied and the amount of polishing is extremely stable. This makes it possible to improve the processing accuracy in partial correction polishing, which removes local shape errors when polishing optical mirror surfaces, for example. It is possible to smooth the difference in level between the processed surface and the non-processed surface that occurs when performing this process, and to obtain a good processed surface shape. [Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings. A. Overall Structure of Polishing Apparatus FIGS. 1 and 2 show the overall structure of an embodiment of a polishing apparatus to which the present invention is applied. In FIG. 1 showing the overall appearance of the device from the front, 10 is a surface plate, 11 is a turning table that is fixed on the surface plate and can be rotated horizontally, and 12 is a turning table 11.
The rotation of the turning table 11 is transmitted through a small diameter gear 14 that meshes with the large diameter gear 13 fixed above the gear 12, and an encoder (hereinafter referred to as the turning angle) that reads the rotation angle of the turning table 11 (hereinafter referred to as the turning angle). Angle detector), 15 is a bracket that fixes the encoder 13 on the surface plate IO. 16 is an origin switch for detecting the origin of the turning angle of the turning table 11, and 17 is a support for fixing the origin switch 16 on the surface plate 1G. 18 is a base on the work side fixed to the rotating gear 12 of the turning table 11; 19 is a linear guide rail fixed to the base 18; 20 is a slider mounted on the linear guide rail 19 and capable of sliding on the linear guide rail 19; 21
2 is a spindle mounted on the slider 20, and 22 is a workpiece drive motor that rotates the workpiece 1 attached to the tip of the spindle 21 via the spindle 21. 23 is a workpiece feed handle for driving the slider 20 to align the center of curvature of the workpiece 1 with the center of rotation of the turning table 11; and 24 is a lock screw for stopping the movement of the slider 20. 25 is a base on the tool side fixed to the surface plate lO, 26 is a linear guide rail fixed to the base 25, 27 is a slider mounted on the linear guide rail 26, and 28 is a slider 2
7 is a feed screw that slides linearly in the horizontal direction; 29 is a handle attached to the feed screw 28; 30 is a bearing that supports the feed screw 28 on the base 25; 31 is a bearing box fixed to the slider 27; 33 is an air slide shaft that is supported by a bearing box 31 and slides in the horizontal direction; 33 is a slide shaft 32;
The weight 33 is a pin 3 protruding from the end of the slide shaft 32.
4 and is attached to the lower end of a wire 36 wound around a pulley 35 attached to a bearing box 31, and acts to press the slide shaft 32 with a constant pressure in the direction of the workpiece 1 by its own weight. 37 is a lock screw that stops the movement of the slider 27. 38 is a tool with a spherical tip (hereinafter referred to as
An abrasive material is uniformly applied and fixed on one surface of the lap tape 39 on the workpiece side, and as the tape 39 moves, the minute protrusions remaining on the surface of the workpiece 1 are scraped with the uniform abrasive material. Drop and mirror polish. 40 is an abrasive supply device that supplies the lap tape 39 between the workpiece 1 and the nose 38, and a supply reel 41 for feeding out the tape.
and a take-up reel 42 for winding the tape. A swing device 201 swings the abrasive supply device 40 in a direction perpendicular to the tape supply direction. Next, in FIG. 2 showing the overall appearance of the device from above, 43 is a turning table drive motor that turns the turning table 11, 44 is a feed screw that slides the slider 20, and the handle 23 is attached to this feed screw 44. installed. 45 is a bearing that supports the feed screw 44. 46 is a scale attached to the base 25, 47 is an origin switch that detects the origin of the scale 46, 48 is a slide shaft drive motor that slides the slide shaft 32, 49
5 is a motor bracket fixed to the bearing box 31, 50 is a feed screw, and 51 is a stopper attached to the feed screw 50. In the above configuration, the work 1 is available in various sizes and can be freely attached to and detached from the spindle 21. When starting work, the worker (operator) turns the handle 23 on the right side of the butt end, reads the value on the scale 46, moves the slider 20 to a position that matches the size of the workpiece 1, tightens the lock screw 24, and moves the slider 20. fix the movement. Next, the operator turns the handle 29 on the left side of the butt end to remove the nose 3 attached to the abrasive supply device (tape feed device) 40.
Slide the slider 27 until 8 comes close to the work 1, and fix the slider 27 with the lock screw 37. Next, when the operator presses down a start button (not shown), the drive motor 48 starts, rotates the feed screw 50, and slides the slide shaft 32 in the direction of the workpiece 1. At this time, by using an aerostatic bearing as the bearing box 31, the running (movement) of the slide shaft 32 can be controlled with high precision. In this way, the nose 38 attached to the abrasive supply device 40 fixed to the slide shaft 32 is attached to the wrap tape 39.
Place it in between and hit it against work 1. At this time, the abrasive coated surface of the wrap tape 39 hits the work 1. Also, since the weight 33 acts on the slide shaft 32, the nose 38
is pressed against the workpiece 1 with a constant pressure. Next, the drive motor 22 is started to rotate the workpiece 1, and at the same time, the drive motor (described later) runs the lap tape 39 under tension in a substantially vertical upward direction along the curved surface of the tip of the nose 38, thereby polishing the lap tape 39. The part where the tip of the nose 38 and the workpiece 1 are in contact with the material is polished. At this time, the amount of polishing with the lap tape 39 depends on the force with which the nose 38 presses the workpiece 1, the pressurizing time, the rotational speed of the workpiece 1, the running speed of the lap tape 39, and the lap tape 39.
varies depending on the type of abrasive applied. The force F with which the nose 38 presses the workpiece 1 is the weight MW of the weight 33.
It can be adjusted by Further, by changing the speed of the drive motor 43, the pressurizing time T during which the nose 38 is in contact with a certain angle of the workpiece 1 via the wrap tape 39 can be adjusted. Further, in order to partially polish the workpiece 1, the drive motor 43 is driven to rotate the rotary table 11 at a relatively high speed to a position (swivel angle) where the nose 38 touches the portion of the workpiece 1 to be polished. The turning angle at this time is encoder 1
Read with 3. Further, by using an aerostatic bearing for the bearing of the turning table 11, highly accurate rotation control can be obtained. B. Structure of rocking device FIG. 32 shows an example of the structure of the rocking device 201 in FIG. 1. In the figure, 202 is an L-shaped bracket, 203a
and 203b are leaf springs, and 204 and 205 are plates. A pair of leaf springs 203a and 203b are fixed with bolts to both end surfaces of plates 204 and 205 arranged at a predetermined interval, and one plate 204 is fixed to a bracket 202 with bolts. 206 is a plunger pin attached to one end of the other plate 205, 207 is a motor (swing motor) attached to the side of the bracket 202 in almost the same direction as the plunger pin 206, and 208 is attached to the shaft of the motor 207. It is a cylindrical cam. The cylindrical cam 208
The tip of the plunger pin 206 is in contact with the cam surface 208a of the cam surface 208a, and by rotating the cylindrical cam 208 by the motor 207, it is applied to the plate 205 via the plunger pin 206 in a direction perpendicular to the supply direction of the wrap tape 39. A reciprocating motion (i.e., rocking) is performed. Bracket 202 of rocking device 201 having the above configuration
is fixed to the end face of the slide shaft 32, and the plate 20
5, a bracket 62 of the abrasive supply device 40 is fixed via a bracket plate 62a. A nose 38, which is a polishing tool, is attached to the tip of the bracket 62. That is, as a result, the abrasive supply device 40 including the nose 38 is attached to the slide shaft 32 so as to be swingable by the swinging device 201. Therefore, when the cylindrical cam 208 is rotated by the motor 207, the plunger pin 20 in contact with the cam surface 208a
As a result of the swinging motion of the plate 205 via the tip 6, the nose 38 can be caused to swing in the direction of the arrow f in the figure. Structure of C8 abrasive supply device FIGS. 3 to 8 show an abrasive supply device 4 to which the present invention is applied.
3 is a front view, FIG. 4 is a right side view, FIG. 5 is a plan view, FIG. 6 is a cross section taken along line A-^ in FIG. 3, and FIG. The B-8 cross section in FIG. 3 and the C-C cross section in FIG. 3 are shown in FIG. In FIG. 3, reference numerals 55 to 60 indicate guide rollers, and the wrap tape 39 supplied from the supply reel 41 is wound and fed in the order of the guide rollers 55 to 60 and a rotationally driven rubber ring 61, and is finally wound. It is wound up with a take-up ream 42. Guide rollers 55.56, 58.60 are roller shafts 55a, 5
6a. Although it is rotatably fixed to the bracket 62 via 58a and 60a, the guide roller 57 is supported via the arm 63! Thk 64 is supported movably by its own weight from the position shown by the solid line in the figure to the position shown by the broken line in this figure, and is supported by upper and lower stoppers 65. [The range of movement upward and downward is restricted by i6. When almost no wrap tape 39 remains on the supply reel 41 or when it comes off the guide roller, the tension of the wrap tape 39 decreases and the guide roller 57 immediately descends due to its own weight, and the microswitch 67 stops the guide roller 57 from descending. is detected via the detection rod 68. 69 is a tension roller that applies appropriate tension to the wrap tape 39; 70 is a tension arm that supports the tension roller 69; 71 is a tension spring that pulls the tension arm 70; and 72 is a support shaft that rotatably supports the tension arm 70. , 73 is a spring support shaft of the tension spring 71. The tension arm 70 is biased by a tension spring 71,
The wrap tape 39 presses the tension roller 69 against the rubber ring 61 and runs between the tension roller 69 and the rubber ring 61.
Apply appropriate tension to the 74 is a sleeve that prevents the wrap tape 39 from coming off the nose 38; the wrap tape 39 passes through the inside of the sleeve 74, turns over at the tip of the nose 38, and passes through the inside of the sleeve 74 again to go to the guide roller 59. . 75
is a belt that transmits rotational force to the take-up reel 42. Next, in FIG. 4, 76 is a reel drive motor that drives the take-up reel 42 and the rubber ring 61, 77a and 77b are a pair of bevel gears that transmit the rotation of the drive motor 76 to the pulley shaft 78, and 79a and 79b are pulleys. A bearing for the shaft 78,
The above-mentioned rubber ring 61 is fixed to the pulley Id178. 80 is a pulley shaft on the driven side, and the driving force is transmitted from the pulley shaft 78 on the driving side via the belt 75. 81 is the bearing of the pulley shaft 80, 82 is the pulley 11it
h80 is a retaining ring, 83 is a thrust washer arranged on both sides of the take-up reel 42, 84 is a bearing of the take-up reel 42,
85 is a presser washer for the take-up reel 42; 86 is a compression spring;
7 connects the take-up reel 42 via a compression spring 86 to a pulley @
This is a cap screw that fixes to 80. In FIG. 5, 88 is a support shaft of the supply reel 42, which is fixed to the bracket 62. Members 89 to 93 are used for attaching and detaching the supply reel 42, and 89 is a thrust washer, 90 is a bearing, 91 is a presser washer, 92 is a compression spring, and 93 is a presser screw. FIG. 6 shows the structure near the arm 63, where 94 is a bearing provided on the roller shaft 57a of the guide roller 57, and 95 is a retaining ring that prevents the guide roller 57 from falling off. A groove portion (guide groove) 57b for guiding the wrap tape 39 is formed on the surface. A bearing 96 rotatably supports the arm 63 to which the guide roller 57 is attached, and is attached to the support shaft 64 and prevented from slipping off by a retaining ring 97. FIG. 7 shows the structure near the tension arm 70, where 98 is a retaining ring attached to support Ii [1172;
1 is a compression spring attached to the tension arm 70, 100 is a retaining ring of the compression spring 99, 101 is a retaining ring of the tension roller 69, 102 is a retaining pin of the tension roller 69, 1
03 is a stopper shaft. Further, FIG. 8 shows the structure in the vicinity of the guide roller 60. Here, 104 is a bearing of the guide roller 60, 105 is a retaining ring, and the guide roller 60 is rotatably fixed to the bracket 62 by the roller shaft 60a. A groove portion (guide groove) 60b for guiding the wrap tape 39 is provided on the circumferential surface of the guide roller 60.
is formed. The other fixed guide rollers 55, 56, 58, 59 shown in FIG. 3 have substantially the same structure as the guide roller 60 shown in FIG. 8. As shown in FIGS. 1 and 32, the abrasive supply device (
The tape feeder 9) 40 has its bracket 62 attached to the slide shaft 32 via the swinging device 201, and moves together with the nose 38 as the slide shaft 32 slides. As shown in FIGS. 3 and 4, the wrap tape 39 wound around the supply reel 42 is
, 58, tip of nose 38, guide roller 59.60
The rubber ring 61 attached to the pulley shaft 78
It is sandwiched between the tension rollers 69 and wound around the rotating take-up reel 14. At this time, the pulley shaft 78 is rotated by the drive motor 76 via gears 77a and 78b, causing the rubber ring 61 to rotate. The rotational speed of the drive motor 76 can be changed arbitrarily, thereby making it possible to vary the running speed of the wrap tape 39. When the pulley shaft 78 rotates, the pulley shaft 80 rotates via the belt 75, and the rotated pulley shaft 80 rotates the take-up reel 41 by the frictional force of the thrust washer 83. The friction force of the thrust washer 83 is
The friction force of the thrust washer 83 is generated by the biasing force of the compression spring 80 bent by the retaining screw 87. The wrap tape 39 wound around the winding wheel 41 gradually increases its winding diameter, and the winding speed becomes faster than the speed at which the tape is running on the rubber ring 61. @80 and the winding wheel 41 are configured to slide through a thrust washer 83, so that the running speed of the wrap tape 39 is always kept constant. Further, the force with which the tension roller 69 presses against the rubber ring 61 is exerted by a tension spring 71, and the pressing force can be changed by changing the position of the hole in the tension arm 70 on which the tension spring 71 is hooked. As will be described later, a tape guide groove is cut into the nose 38 to prevent the wrap tape 39 from coming off, and the tip of the nose 38 is shaped into a spherical shape to enable polishing of minute parts of the workpiece 1. Therefore, it matches workpiece 1 at a point. Further, a cylindrical sleeve 74 is fitted around the outer periphery of the nose 38, and the wrap tape 39 is fed between the upper and lower grooves of the sleeve 74 and the nose 38, so that the wrap tape 39 does not come off the nose 38. Further, the guide roller 57 is attached to the arm 63 and supported by the tension of the wrap tape 39. The wrap tape 39 wound on the supply reel 42 is wound up by the take-up reel 41 as described above, and finally the wrap tape 39 is removed from the supply reel 42 and the tension of the wrap tape 39 is reduced. The guide rollers 57 can no longer be supported, and the guide rollers 57 move downward toward the lower end. As soon as the guide roller 57 is lowered, the micro switch δ7
is activated, the drive motor 76 is stopped, and the wrap tape 39 is
stop running. On the other hand, as shown in FIG. 5, the supply reel 42 is braked by the frictional force of the thrust washer 89, applying tension to the wrap tape 39. Thrust washer 8
The frictional force 9 is applied by adjusting the cap screw 93 to deflect the compression spring 92. When storing the abrasive supply device 40 for a long period of time, if the tension roller 69 is kept pressed against the rubber ring 61,
Since the rubber ring 61 is deformed and the running of the wrap tape 39 becomes unstable during processing, the stopper shaft 103 is inserted into the hole drilled in the bracket 62 to fix the tension roller 69, and the tension roller 69 separates from the rubber ring 61. (See Figure 7). D. Structure of Nose (Processing Tool) FIGS. 9 to 18 show examples of the structure of the nose 38 according to the embodiment of the present invention. Figure 9 is a longitudinal section of the nose 38 portion during polishing, 1θ
The drawings show a cross section taken along line XX in FIG. 9, FIG. 11 shows a longitudinal section of only the nose 38, and FIG. 12 shows its right side. Figures 9 to 12
In the figure, 38a is a tape guide groove of the nose 38 formed along the running direction of the wrap tape 39, and 38b is a spherical portion (convex curved surface) at the tip of the nose 38. Furthermore, a cylindrical sleeve 74 that covers the groove 38a of the nose 38 is fitted at the position of the groove 38a. The wrap tape 39 is guided by the guide rollers 58 and enters between the groove 38a on the lower side of the nose 38 and the sleeve 74, and
It passes through the exposed spherical tip 38b and reenters between the groove 38a on the upper side of the nose 38 and the sleeve 74, and is guided to the guide roller 59. In this way, the sleeve 74
a, the wrap tape 39 is guided accurately and does not come off. Also, since the tip portion 38b of the nose 38 is spherical, it makes contact with the workpiece 1 at a point, making it possible to polish minute parts of the workpiece 1. Become. The shape of the tip of the nose 38 is required to have high shape accuracy in order to apply pressure to the correct processing position, and particularly in the embodiment of the present invention, highly accurate sphericity is required. However, in the integrally shaped nose 38 as shown in FIGS. 9 to 12, it is difficult to process the spherical surface of the tip portion 38b, and it is difficult to obtain a highly accurate spherical surface. 13 to 18 show an embodiment in which a separate steel ball 106 is attached to the tip of the nose 38 to obtain a highly accurate spherical surface.The steel ball 106 has the required high sphericity. For example, commercially available steel balls (such as bearing balls) can also be used. This steel ball 106 is fixedly attached to the tip of the nose body 38c with an adhesive or the like, and tape guide grooves IQ6a are formed on the upper and lower surfaces of the nose body 38 and the steel ball 106. Work 1
When the amount of machining is large, the amount of polishing is increased by using a steel ball 10B with a relatively large diameter as shown in the embodiment shown in FIGS. 17th
As shown in FIG. 18, it is preferable to use a steel ball 108 with a relatively small diameter. E. Processing Principle FIGS. 19 to 21 show the processing principle of the embodiment of the present invention. As shown in FIG. 19, with the surface of the lap tape 39 coated with the abrasive material facing the workpiece 1, press the tip of the nose 38 against the part of the workpiece 1 to be polished with the lap tape 39 sandwiched between the workpieces 1 and 1. When the wrap tape 39 is rotated in the clockwise direction of the arrow and the wrap tape 39 is run upward, the part of the workpiece 1 that the nose 38 hits is polished. Since the abrasive material on the wrap tape 39 can be applied uniformly,
There are no problems like with conventional floating abrasive grains, and the amount of polishing can be kept constant. In addition, new abrasive material is always supplied to the workpiece 1 during polishing by the running of the lap tape 39, so clogging of the abrasive material does not occur, and the machined surface is always polished with an ideal cutting edge, so the polishing The amount is stabilized,
A highly accurate mirror finish can be obtained. In addition, since the tool (nose) 38 itself is not rotated, there is no problem caused by rotational wobbling of the tool, and since the tip of the nose 38 is made into a true spherical surface, the nose 38 hits the work l at a point, and only a very small area is affected. Polishing can be done with high precision. Furthermore, since the constant pressure with which the nose 38 is pressed against the workpiece L is adjusted by the weight 33, the workpiece 1 is pressed at the optimum machining pressure.
can be polished, and the amount of processing can be stabilized. Here, the amount of polishing performed by the lap tape 39 is:
As mentioned above, it is determined by the rotational speed of the workpiece 1, the traveling speed of the wrap tape 39, the type of abrasive material applied to the wrap tape 39, and the pressure and pressurization time with which the nose 38 is pressed against the workpiece 1. Therefore, as shown in FIG. 20, the workpiece 1 is rotated at a constant speed v2, and the wrap tape 39 is rotated at a speed V. If the nose 38 travels at a constant speed, the pressing force F that the nose 38 presses against the workpiece 1 is adjusted to a constant pressure by the weight 33, and the type of abrasive material in the lap tape 20 is constant, then the nose 38
It can be seen that by adjusting and controlling the pressurizing time for pressing the workpiece 1 against the workpiece 1, it is possible to appropriately control the polishing area and obtain highly accurate mirror polishing. However, the microprotrusion portion 107 on the workpiece 1 is generally large/j
), and its position also varies as shown in FIG. 38, and it is necessary to increase or decrease the pressing time depending on the size of the protrusion 107. This movement of the workpiece 1 is achieved by controlling the rotation angle of the rotation table 11 with the drive motor 43, and the pressurization time is achieved by variable control of the rotation speed of the rotation table 11. Furthermore, it has been confirmed through experiments that the amount of machining described above and the rotation speed are in an inversely proportional relationship. Furthermore, when polishing is performed by bringing the lap tape 39 into rocking contact with the processing surface of the workpiece 1 using the swinging device 201, it is possible to smooth out the inclination of minute steps that occur on the processing surface of the workpiece 1 during the processing. Therefore, a good machined surface shape can be obtained. For example, according to the processing principle described above, the wrap tape 39
When not rocking, as shown in FIG. 33 (8), a step is created in the machined portion m of the machined surface of the workpiece 1, and the slope S at the boundary becomes steep. However, when the lap tape 39 is oscillated and brought into contact with each other for polishing, the slope S' at the boundary becomes gentler as shown in FIG. Connects smoothly,
Shows good surface shape. The above-mentioned effects of the present invention will be explained in more detail using actual processing examples. FIGS. 34(A) and 34(B) show interference fringes on the machined surface of workpiece 1 that has been polished.
A) and (B) are workpiece 1 with the cross-sectional shape shown in Fig. 35.
36 is a reproduction of a photograph of the interference fringes of the spherical portion when the spherical portion is processed as shown in FIG. 36 under the conditions shown in Table 1. FIG. In FIG. 34 (A), which is a copy of an interference fringe photograph of the workpiece 1a that was polished without using the rocking device 201 of this embodiment, the boundary between the processed part (m) and the unprocessed part (P) is It is clear that the slope (S) is steep. On the other hand, in Fig. 34 (B), which is a copy of the interference fringe photograph of workpiece 1b polished using +I Moso Fa 2 Q l, the boundary between the processed part (m) and the unprocessed part (P) is shown. (S
′) is not clear, and it can be seen that the machined and unprocessed surfaces are smoothly continuous. In addition, Fig. 34 (A), (
The height difference of the workpiece 1 in B) is about 0.02 μm. F. Control 9 Sound Structure FIG. 22 shows an example of the circuit structure of the control system according to the embodiment of the present invention. In this figure, reference numeral 110 denotes a control computer, which controls the processing according to the present invention in accordance with the control procedure shown in FIG. 23, which is stored in advance in a memory 111. 112 is a work shaft motor driver (drive circuit) that drives and controls the drive motor 22 that rotates the workpiece 1; 113 is a tape feed motor driver that drives and controls the drive motor 76 that sends the wrap tape 39; 114 is a drive shaft that drives the nose 38 to the slide shaft 32; A nose feed motor driver 221 drives and controls the drive motor 48 that is sent via the swing motor 207.
These motor drivers 112 to 114 and 221 control the rotation of the corresponding motors in accordance with command signals (control signals) from the control computer 110. Reference numeral 115 denotes a rotation axis angle detector 2 that manually inputs the output from the encoder 13 that detects the rotation angle of the rotation table 11 and sends rotation axis angle data to the control computer 110.
11 is a measuring device manual interface for manually inputting the output of a non-contact measuring device 121 shown in FIG. 24, which will be described later. Reference numeral 118 denotes a pivot shaft motor driver that drives and controls the drive motor 43 that rotates (swivels) the pivot table 11 . Reference numeral 117 denotes a cannibal program input unit for inputting a cannibal program as described below supplied from the main computer 118, and the cannibal program is composed of combined data of the rotation angle and rotation speed of the rotation table 11. Reference numeral 119 is an FD driver that drives and controls a floppy disk (FD) 120. Next, an example of the control operation of the embodiment of the present invention will be explained with reference to the flowchart of FIG. First, before partially correcting the workpiece 1, the control computer 110 inputs a correction program (cannibal program) from the cannibal program manual section 117 and stores it in a predetermined area of the memory 111 (step Sl). Next, the operator turns the handle 29 to align the center of curvature of the workpiece 1 with the center of rotation of the rotating table 11, but when the control computer 110 confirms this alignment (step S2), the control computer 110 controls the memory 111. issues a command to the rotation axis motor driver 116 to operate the drive motor 43 based on the correction program stored in the
The turning table 11 is turned to the part to be corrected on the workpiece 1 (step S3). Next, the control computer 110 issues a command to the work shaft motor driver 112 to operate the drive motor 22,
While rotating the workpiece 1, a command is issued to the tape feed motor driver 113 to operate the drive motor 76 to run the wrap tape 39, and a command is issued to the swing motor driver 221 to start the swing motor 207. Activate it (step S4.). Next, the control computer 110 issues a command to the nose feed motor driver 114 to operate the drive motor 48, and stops the nose 38 against the workpiece 1 with the wrap tape 39 sandwiched therebetween (step S5). Subsequently, the control computer 110 gives a rotation speed command to the rotation axis motor driver 116 based on the modification program written in the memory 111 to operate the motor 43, and transmits rotation angle data from the encoder 13 to the rotation angle detector. 115 (step S6). Next, the control computer 110 outputs the rotation speed corresponding to the detected rotation angle to the rotation axis motor driver 116 based on the correction program stored in the memory 111, and controls the rotation speed of the motor 43 (step S7). )
. Step S6 above. The control operation in S7 is sequentially repeated until the detected value of the encoder 13 reaches the predetermined end angle stored in the correction program, and the detected rotation angle detected by the encoder 13 reaches the above-mentioned predetermined end angle. When the angle is reached (step S8), the control computer 110 issues a command to the nose feed motor driver 114 to operate the drive motor 48 to separate the wrap tape 39 from the workpiece 1 (step S9), and the workpiece axis motor driver 112 and A command is issued to the tape feed motor driver 113 and the swing motor driver 221 to stop the drive motors 22, 207 and 76, and the correction polishing of one part is completed (step SIO). When all of the data in the correction program is not completed, that is, when other parts of the work 1 are also to be corrected and polished, the process returns to step S3 described above and the processes from step S3 to SIO are repeated until the correction program is completed (step 5ll). . G. Structure of machining amount measuring means By providing a non-contact measuring device to the apparatus according to the embodiment of the present invention shown in FIG. 1, the machining amount measuring means (
The 24th point is that it can be easily used (shared) as a device).
As shown in the figure. In FIG. 24, 121 is a non-contact measuring device, and a general non-contact measuring device such as a non-contact electric micrometer, a laser range finder, an optical scale, etc. can be used. The non-contact measuring device 121 may be installed at any position as long as it can measure the displacement of the slide shaft 32 that is integrally displaced with the nose 38.
It is placed behind 2. 122 is a position-adjustable stand that fixes the non-contact measuring device 121 at a mounting position, and 123 is a measuring meter that can amplify and display the output signal of the non-contact measuring device 121. After the measurement data of the non-contact measuring device 121 is amplified,
It is converted into a digital signal, sent to the control computer 110 in FIG. 22, and embedded in the IA. Other components are the same as those in the embodiment shown in FIG. 1, so detailed explanation thereof will be omitted. In the above configuration, the lap tape (tape-like abrasive member) 39 is pressed against the processing surface of the workpiece (workpiece) 1 for grinding and
The wrap tape 39 is removed from the above-mentioned nose (pressing member) 38 to be polished, and the nose 38 is brought into direct contact with the workpiece 1 as a probe of a processing amount measuring means. After bringing the nose 38 into direct contact with the workpiece 1, the turning angle of the turning table 11 is set to the original position, the bearing box 31 is fixed with the lock screw 37, and the turning table 11 is rotated. In this way, when the workpiece 1 is rotated after the nose 38 is brought into direct contact with the workpiece 1, the nose 38 is moved against the workpiece at a constant pressure via the slide shaft 32 by the pressing force of the weight 33.
As shown in Fig. 25, the workpiece 1
The slide shaft 32 to which the nose 38 is attached is also displaced integrally with the nose 38 at the same time. The displacement of which slide shaft 32 is measured at a predetermined pitch using a non-contact measuring device 121 and outputted to the control computer 110. The control computer 110 uses the measurement data of the measuring device 121 and the rotation table 11 obtained from the encoder 13.
After temporarily storing the turning angle data in the memory 11,
The difference (error) from the design data (ideal value) of the workpiece 1 is determined, and correction data consisting of the correction processing amount and its processing position is created. In particular, in this embodiment, the slide shaft 32 is supported by an air bearing in the bearing box 31, an appropriate constant contact pressure is applied by the weight 33, and the tip of the nose 38 is formed into a spherical shape for point contact. The non-contact measurement device 121 has extremely good followability, and even minute changes in unevenness on the surface of the workpiece 1 can be measured extremely accurately, for example, in units of □□ μm. Furthermore, in this embodiment, the suppression member, which is a tool, can also be used as a probe, so there is no need to use an expensive dedicated measuring device, and problems caused by setting adjustment of the workpiece 1 (setting deviation) can be avoided. There are advantages that do not arise;
In addition, corrective grinding and polishing can be performed immediately after measurement, resulting in a significant reduction in processing time. Furthermore, since it becomes possible to fully automate everything from measurement to correction processing, operational work is significantly reduced, leading to reductions in manufacturing costs. H1 Structure of processing data creation means FIG. 26 shows an example of the structure of the processing data creation means for creating processing data (correction program) provided to the partial correction polishing apparatus as shown in FIG. 131 is a measuring device that outputs an error curve (data) from measurement data and an ideal curve (data) to be described later, and 132 is a floppy disk (FD) that provides the ideal curve to the measuring device 131°. 133 is an automatic programmer that outputs machining data from an error curve from the measuring device 131 and a cutting amount curve (data) to be described later; 134 is a floppy disk that provides the cutting amount curve to the automatic programmer 133; H5 is an automatic programmer 13;
This is a processing machine as shown in FIG. 1 which inputs the processing data obtained from Step 3 as a correction program and performs partial correction polishing processing. The measuring device 131 includes, for example, a displacement measuring means such as the non-contact electric micrometer 121 shown in FIG. 24, and arithmetic control means such as the control computer or main computer 118 shown in FIG. According to the processing procedure as shown in FIG. 29 stored in advance in the storage means, the measured value of the workpiece 1 represented by the turning angle θ and the deviation from the spherical surface of the workpiece 1 as shown in FIG. 27(A),
The ideal curve (
Based on the deviation γ from the design curve), an error curve expressed using the γ-θ method as shown in FIG. 27(B) is calculated and output. The automatic programmer 133 includes arithmetic control means such as the main computer 118 shown in FIG.
31 and the error curve as shown in FIG.
Based on the cutting amount curve as shown in FIG. 7(C), machining data as shown in FIG. 27(D) is output according to the processing procedure shown in FIG. 30. 'fS27 Figure (C) shows a cutting amount curve that represents the relationship between the turning angle θ and the cutting amount when the turning table 11 is turned at a constant speed. 38 is located near the center of the rotating work 1, and as the turning angle θ increases, the nose 38 relatively drives toward the outer circumferential direction of the work 1.
The 0 circumferential speed decreases at the center, and if the turning speed is constant, the machining amount decreases as the turning angle θ increases.
Figure (C) shows. Further, the amount of cutting decreases as the rotation speed increases, and increases as the rotation speed decreases, so the amount of cutting is inversely proportional to the rotation speed, as shown by the broken line curve J in FIG. 27(C). Therefore, the automatic programmer 33 compares the error curve and the cutting amount curve at a predetermined pitch (at the same turning angle), and calculates the turning speed for each turning angle during partial correction machining. For example, at a certain turning angle e1, if the error is 5 μm and the cutting amount at a constant turning speed v0 is 1 μm, the turning speed V during machining becomes V;-. In addition, since the actual correction machining parts are thought to be scattered randomly on the workpiece 1, the machining data given to the processing machine 135 is calculated at a turning speed between certain turning angles, as shown in FIG. This is an instruction to make a turn. The processing machine 135 inputs the processing data as a correction program and processes the workpiece 1 according to the IIJ control procedure as shown in FIG. 31 or the control procedure as shown in FIG. 23 described above.
Perform partial correction polishing. Next, an example of the operation of the measuring device 131 described above will be described in detail with reference to the flowchart in FIG. As shown in FIG. 24 above, a non-contact measuring device (e.g.
A non-contact electric micrometer) 121 is placed behind the slide shaft 32, the workpiece 1 is attached to the spindle 21,
By operating the handle 29, align the center of curvature of the workpiece 1 with the center of rotation of the turning table 11, remove the wrap tape 39 from the nose 38, bring the nose 38 closer to the workpiece 1 by operating the handle 29, and lock the bearing box 31 with the lock nut. Fix it at 37. Further, the weight 33 is selected to provide an appropriate contact pressure. After completing the above preparation work, the operator presses a measurement start button on the operation desk (not shown). By pressing this button, the control procedure shown in FIG. 29 is started. First, in response to a measurement start instruction, the control computer 11
0 is connected to the 1st shift motor 4 via the rotation axis motor driver 116.
3 and set the rotation angle of the rotation table 11 to the origin O°. This origin position is detected by the origin switch 16 (see FIG. 1) (step 521). Next, the control computer 110 starts the drive motor 48 via the nose feeder driver 114 to advance the slide shaft 32 to move the nose (hereinafter referred to as a contact).
38 and workpiece 1 are brought into direct contact (step 522)
. Next, the control computer 110 sets the current position of the slide shaft 32 to zero (step 523), and outputs a drive signal to the rotation axis motor driver 116 to rotate the rotation table 11 and the gear 12 of the table at a constant speed. At the same time (step 524), the position of the slide shaft 32 is inputted from the non-contact measuring device 121 at every fixed pitch angle (swivel angle), and is sequentially stored in the memory 111 (step 525).
), these steps S24 and 525 are repeated until the end angle of the turning table 11 is reached (step 526), and the turning angle of the turning table 111 is detected by the encoder 13. As a result, data of a measured value curve as shown in FIG. 27(A) is stored in the memory 111. When the detected rotation angle reaches the predetermined end angle of the rotation table 111, the control computer 110 outputs a command signal to the nose sending motor driver 114 to reversely rotate the drive motor 48, thereby causing the slide N32 to retreat and make contact. step 527) separating the child 38 from the workpiece 1.6);
Subsequently, the above-mentioned measurement data D1 stored in the memory 111
The value (DI-02) obtained by subtracting the ideal curve (ideal value data) D2 of the floppy disk 132 from the error value γ (θ)
The calculation is performed for each pitch angle of the turning angle θ (step 528), and the calculation results are sequentially written to the floppy disk 112 as an error curve (data) (step 52).
9). Next, an example of the operation of the automatic programmer 133 described above will be described in detail with reference to the flowchart in FIG. First, the control computer 110 (or the main computer 118) reads an error curve (measurement data) from the floppy disk 112 via the FD driver 119, and stores it in the memory 111. Further, the cutting amount curve (cutting amount data) is read from the floppy disk 113 and stored in the memory 111 (step 531). Next, calculate the cutting time for each turning angle from the above-mentioned cutting amount data (cutting amount curve) and measurement data (error curve) (Step 532), and calculate the turning speed for each corresponding turning angle from the reciprocal of the calculated cutting time. The calculation result is stored in the floppy disk 120 as processed data (step 534). FIG. 31 shows an example of the operation of the processing machine 135 described above, but since it is almost the same as the control procedure shown in FIG. 23 described above, detailed explanation thereof will be omitted. When removing the protruding part of the machined surface of the workpiece 1 by grinding and polishing, as shown in FIG. In the example, the turning speed (V2) is controlled, but the present invention is not limited to this. For example, the speed (V2) of the lap tape 39 is controlled in proportion to the polishing (47 IC grinding amount) while keeping the speed (V2) of the workpiece 1 constant. The control may be carried out using both controls, or both may be controlled in combination. (2) Composition of pressure means In the embodiment of the present invention, a weight 33 is used as a means for applying processing pressure in the direction of the workpiece to the tool of the polishing device equipped with the abrasive supply device, as shown in FIGS. 1 and 2. As shown, the slide shaft 32 with the abrasive supply device 40 attached is inserted into the bearing box 3.
The slide shaft 3 is statically supported by the static pressure air bearing 1.
A constant pressing force is applied to the re-nose (tool) 38 by the weight of the weight 33 via a wire 36 whose one end is connected to the re-nose (tool) 38. In this way, since the machining pressure is applied by the weight 33, there is no change in the machining pressure due to the movement of the slide shaft 32.
Also, slide! 1Ih32 is supported by static pressure, so
The nose 38 traces the shape of the polished surface of the workpiece 1 smoothly. Further, since the pressing force of the wrap tape 39 on the workpiece 1 is always constant, stable polishing can be performed. Furthermore, as shown in FIG. 24, even when used as a polishing amount measuring means, extremely highly accurate measurement data can be obtained for the same reason as described above using the pressurizing means. Note that the present invention can of course be applied to a grinding device. [Effects of the Invention] As explained above, according to the present invention, an abrasive tape is supplied between the rotating workpiece processing surface and a swinging polishing tool, and the tape is used to process the workpiece by the polishing tool. Since it is pressed against the surface with a constant pressure while oscillating, a uniform new abrasive material is constantly supplied and the amount of polishing is extremely stable.This eliminates local shape errors when processing optical mirror surfaces, for example. It is possible to improve the machining accuracy in partial correction polishing, which involves polishing while polishing, and it is also possible to smooth out the difference in level between the machined surface and the non-machined surface that occurs when performing partial correction, and to obtain a good machined surface shape. can.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an example of the overall configuration of a polishing device to which the present invention is applied, FIG. 2 is a plan view thereof, and FIG. 3 is a front view showing an example of the overall configuration of the abrasive supply device of FIG. 1. , Figure 4 is a right side view of the same, Figure 5 is a front view of the same, Figure 6 is a sectional view taken along the ^-A section line of Figure 3, and Figure 7 is a section taken along the 8-'B section line of Figure 3. 8 is a sectional view taken along the line C-C in FIG. 3, FIG. 9 is a longitudinal sectional view showing an example of the structure of the nose (polishing tool) in FIG. 1, and FIG. is a cross-sectional view taken along the line X-X in FIG.
Fig. 1 is a vertical sectional view showing the configuration of only the nose in Fig. 9, Fig. 12 is a right side view of the nose in Fig. 11, Fig. 13 is a longitudinal sectional view showing another embodiment of the nose, and Fig. 14. is the first 13
15 is a longitudinal sectional view showing a modified example of the nose; FIG. 16 is a right side view of the nose in FIG. 15;
FIG. 17 is a longitudinal sectional view showing still another modification of the nose, FIG. 18 is a right side view of the nose shown in FIG. 17, and FIG. FIG. 20 is a schematic diagram showing the processing principle of the embodiment of the present invention. FIG. 21 is a sectional view taken along the Y-Y cutting line in FIG. 19. FIG. 22 is a block diagram showing an example of the circuit configuration of the control system of the embodiment of the present invention. , FIG. 23 is a flowchart showing an example of control operation during machining in the embodiment of the present invention, FIG. 24 is a front view showing the configuration of the embodiment of the present invention when the polishing device is shared as a polishing amount measuring means, and FIG. 25 is the second
4 is a horizontal sectional view showing the nose portion during measurement, FIG. 26 is a block diagram showing the configuration of the processing data creation system according to the embodiment of the present invention, and FIGS. 27(A) to (D) are shown in FIG. 28 is an explanatory diagram showing a specific example of the processed data in FIG. 26; FIG. 29 is a flowchart showing an example of the operation of the measuring instrument in FIG. 26; 30. 31 is a flowchart showing an example of the operation of the processing machine shown in FIG. 26; FIG. 32 is a plan view showing the configuration of the swinging device shown in FIG. 1; Figure 33 is an explanatory diagram showing the effect of machining using a rocking device, Figure 34 is a reproduction of an interferometer photograph showing interference fringes on the machined surface, and Figure 35 shows an example of machining using a rocking device. 36 is a sectional view illustrating the processing range of the workpiece shown in FIG. 35, and FIG. 37 is a front view of main parts showing the configuration of a conventional apparatus. DESCRIPTION OF SYMBOLS 1... Workpiece, 11... Turning table, 13... Encoder, 16... Origin switch, 20... Slider, 21... Spindle, 22... Work drive motor, 23... Handle, 24... Lock screw, 27... Slider, 28... Feed screw, 29... Handle, 30... Bearing box, 32... Slide shaft, 33... Weight, 37. ... Lock screw, 38 ... Nose (contactor), 39 ... Wrap tape, 40 ... Abrasive material supply device, 41 ... Supply reel, 42 ... Take-up reel, 43 ... Swivel table drive motor, 46...Scale, 47...Origin switch, 48...Slide shaft drive motor, 55-60...Guide roller, 61...Rubber ring, 63...Arm, 67 ... Micro switch, 69 ... Tension roller, 70 ... Tension arm, 76 ... Reel drive motor, 83 ... Thrust washer, 89 ... Thrust washer, 106° ... Steel ball, 110... Control computer, 111-... Memory, 112 to 114. 116... Motor driver, 117
. . . Cannibal program input unit, 121 . Swing motor, 221... Swing motor driver. Ron, he, he,) 1 Toro 4 (1')
(') 滌
Fig. 17 Fig. 18] Fig. 13 Fig. 11 - 1st view Fig. 13 - 1st view Fig. 14 Work rotation direction Fig. 21 Figure 28 Automatic 70 Grammar Figure 30 Processing machine 40. Figure 32 Figure 33 (B) Figure 36 Fir Prefecture R Lid /) Main part front view Figure 37

Claims (1)

[Scope of Claims] 1) Pressure means that presses an abrasive tool against a rotating workpiece processing surface at a constant pressure; and a tape supply that supplies an abrasive tape between the polishing tool and the workpiece processing surface. A polishing device comprising: a means for rocking the polishing tool; and a rocking means for rocking the polishing tool.