JPWO2010150757A1 - Glass disk polishing apparatus and glass disk polishing method - Google Patents

Abstract

The glass disk polishing apparatus includes a base, a lower surface plate for polishing the lower surface of the glass disk held by the carrier, an upper surface plate for polishing the upper surface of the glass disk, an elevating mechanism for moving the upper surface plate up and down, The upper surface plate is relatively opposed to the lower surface plate in a state where the driving unit provided on the base and the upper polishing pad are in contact with the upper surface of the glass disk and the lower surface of the glass disk is in contact with the lower polishing pad. A rotation transmission mechanism for transmitting the driving force of the drive unit so as to rotate, the rotation transmission mechanism having a drive shaft for transmitting the rotation torque of the drive unit and a cover to which an upper end of the drive shaft is fitted. A disk-shaped torque transmission member having a drive hole and disposed above the upper surface plate; and a connection mechanism for connecting an outer periphery of the upper surface plate and an outer periphery of the disk-shaped torque transmission member. The rotation of the disk-shaped torque transmission member The wherein the transmitting to the outer periphery of the upper surface plate through the communicator.

Description

  The present invention relates to a glass disk polishing apparatus and a polishing method, and more particularly to a glass disk polishing apparatus and a glass disk polishing method for polishing the front and back surfaces of a glass disk, and a magnetic recording medium manufactured using the polishing apparatus or the polishing method. The present invention relates to a method for manufacturing a glass substrate.

  For example, in the process of manufacturing a glass disk for a magnetic disk, the glass disk is processed to a predetermined thickness by polishing the upper and lower surfaces of the glass disk. In such a glass disk polishing step, a carrier having a large number of disk storage holes is placed on the lower surface plate of the polishing apparatus, the carrier is rotated in the circumferential direction, and the upper surface of the glass disk stored in the disk storage hole And the lower surface is polished. In the polishing apparatus, the upper surface plate and the lower surface plate are reversed while pressing the upper polishing pad held on the upper surface plate and the lower polishing pad held on the lower surface plate against the upper and lower surfaces of the glass disk. The upper and lower surfaces of a plurality of glass disks are simultaneously polished so as to be in the same direction, thereby increasing the polishing efficiency (see, for example, Patent Document 1).

  The upper and lower surface plates are made of iron in order to increase the planar accuracy and parallelism on the polishing surface, and the diameter increases as the number of glass disks to be polished (the number of disks stored and held in the carrier) increases. In addition, the weight increases.

  In the polishing apparatus of Patent Document 1, an upper surface plate is supported by an air cylinder device for lifting and lowering and a plane joint and a parallelism with respect to the lower surface plate can be adjusted. It has a suspension structure suspended through. The rotation transmission mechanism for rotating the upper surface plate is provided on the base side that supports the lower surface plate, and the upper surface plate has a serration engaging recess in the drive shaft that penetrates the center hole of the upper surface plate. A key (claw) protruding toward the inner peripheral side is engaged, and the rotational torque of the drive shaft is transmitted to the upper surface plate.

  As a polishing apparatus different from the above, a connecting mechanism that connects the upper air plate apparatus for moving up and down the upper surface plate and the upper surface plate is configured to be positioned substantially on the same plane as the polishing surface of the upper surface plate. There are some (see, for example, Patent Document 2).

Japanese Patent Laid-Open No. 2002-355752 Japanese Unexamined Patent Publication No. 2006-212734

  In the polishing apparatus described in Patent Document 1, a universal joint, which is a connecting portion between an elevating air cylinder device for raising and lowering an upper surface plate, and the upper surface plate is suspended at a height position above the upper surface plate. Due to the structure, there is a problem that the upper surface plate swings (pendulum operation) with the universal joint as a fulcrum. In this way, when the upper surface plate swings like a pendulum, the distance between the polishing surface and the upper surface plate is not constant over the entire surface.For example, the polishing amount near the outer periphery is larger than the center portion of the upper surface plate. There is a high possibility that the thickness of each of the plurality of glass disks after the fluctuation will not be uniform and will be polished so that a part of the surface of the glass disk polished near the outer periphery of the upper surface plate is inclined.

  Further, in the polishing apparatus described in Patent Document 2, the coupling mechanism (swing fulcrum) that connects the drive shaft and the inner periphery of the upper surface plate is located on substantially the same plane as the polishing surface of the upper surface plate. The problem that the upper surface plate like the above cited reference 1 swings like a pendulum and warps upward is solved. However, in the cited document 2, since the connection mechanism is configured to connect the drive shaft and the inner periphery of the upper surface plate by a gyro, the connection mechanism arranged on the outer periphery of the drive shaft has a large diameter. As a result, the inner periphery and outer periphery of the upper surface plate become larger in diameter, and the area that cannot be polished near the rotation center increases, and there is a problem that the entire apparatus becomes larger in order to secure the polishing area.

  Therefore, the present invention maintains the upper surface plate parallel to the lower surface plate, and uses the glass disk polishing apparatus and the glass disk polishing method and the polishing apparatus or the polishing method to solve the above-mentioned problems. An object of the present invention is to provide a method for producing a glass substrate for a magnetic recording medium.

In order to solve the above problems, the present invention has the following means.
(1) The present invention comprises a base,
A lower surface plate having a lower polishing pad that is supported by the base and polishes the lower surfaces of a plurality of glass disks held by a carrier;
An upper surface plate having an upper polishing pad disposed on the lower surface plate so as to face the upper surfaces of the plurality of glass disks;
An elevating mechanism supported above the base and elevating the upper surface plate;
A drive unit provided on the base;
The upper polishing pad is brought into contact with the upper surfaces of the plurality of glass disks by the lowering operation of the lifting mechanism, and the upper surface plate is moved to the lower surface plate in a state where the lower surfaces of the plurality of glass disks are in contact with the lower polishing pads. In a glass disk polishing apparatus having a rotation transmission mechanism that transmits a driving force of the driving unit so as to rotate relative to
The rotation transmission mechanism is
A drive shaft extending in a vertical direction from the drive unit and transmitting a rotational torque of the drive unit;
A disk-shaped torque transmission member having a driven hole into which the upper end of the drive shaft is fitted, and disposed above the upper surface plate;
A connection mechanism provided at a height position near the upper polishing pad, and connecting between an outer periphery of the upper surface plate and an outer periphery of the disk-shaped torque transmission member;
The rotation of the disk-shaped torque transmission member is transmitted to the outer periphery of the upper surface plate via the connection mechanism.
(2) The present invention is characterized in that the upper surface plate is formed of any one of an aluminum alloy, titanium, and carbon fiber reinforced plastic.
(3) The present invention is characterized in that the disk-shaped torque transmission member has a pressurizing portion that presses the entire upper surface of the upper surface plate downward.
(4) In the present invention, the pressing part is
An air bag formed in an annular shape so as to press the entire upper surface of the upper surface plate;
A compressed air supply unit for supplying compressed air to the air bag,
The upper surface plate is characterized in that the upper polishing pad is pressed against each upper surface of the plurality of glass disks with a uniform pressure by air pressure of an air bag filled with its own weight and compressed air.
(5) In the present invention, the compressed air supply unit supplies and pressurizes compressed air to the air bag immediately after the polishing by the upper surface plate, and pressurizes the air in the air bag before the polishing by the upper surface plate is completed. And the pressure is reduced.
(6) In the present invention, a distance in a height direction between the polishing surface of the upper polishing pad and a rotational torque transmission position that transmits rotational torque to the upper surface plate via the coupling mechanism is 100 mm or less. It is characterized by setting.
(7) According to the present invention, the upper platen holding the upper polishing pad is lowered to contact the upper surface of the plurality of glass disks held by the carrier, and the lower surfaces of the plurality of glass disks are lowered. In the glass disk polishing method of polishing the upper surface and the lower surface of the plurality of glass disks by rotating the upper surface plate relative to the lower surface plate in a state of being in contact with the lower polishing pad held by the plate,
Lowering the upper surface plate and fitting a driven hole of a disk-shaped torque transmission member connected to the upper side of the upper surface plate to the upper end of the drive shaft;
Compressed air is supplied to an air bag disposed between the disk-shaped torque transmitting member and the upper surface plate, and a uniform pressure is applied to the entire circumference of the upper polishing pad by the air pressure of the air bag and the weight of the upper surface plate. And pressing the upper surface of the plurality of glass disks, and pressing the lower surface of the plurality of glass disks against the lower polishing pad,
The rotation of the disk-shaped torque transmission member is transmitted to the outer periphery of the upper surface plate via a connection mechanism that connects the outer periphery of the disk-shaped torque transmission member and the outer surface of the upper surface plate, and the upper polishing pad is moved to the lower surface. Polishing the upper and lower surfaces of the plurality of glass disks by rotating relative to the side polishing pad;
After the polishing of the upper and lower surfaces of the plurality of glass disks is completed, the air in the air bag is exhausted, and the upper polishing plate is raised to move the upper polishing pad above the plurality of glass disks. When,
It is characterized by including.
(8) The present invention provides a glass substrate for a magnetic recording medium, comprising: a shape imparting step in which a glass substrate having a plate shape is formed into a disk shape; a polishing step of a main plane of the glass substrate; and a cleaning step of the glass substrate. In this manufacturing method, the polishing step is a method for manufacturing a glass substrate for a magnetic recording medium in which both main planes of the glass substrate are simultaneously polished using the glass disk polishing apparatus according to any one of (1) to (6). is there.
(9) The present invention provides a glass substrate for a magnetic recording medium, comprising: a shape imparting step in which a glass substrate having a plate shape is formed into a disk shape; a polishing step of a main plane of the glass substrate; and a cleaning step of the glass substrate. In this manufacturing method, the polishing step is a method for manufacturing a glass substrate for a magnetic recording medium in which both main planes of the glass substrate are simultaneously polished by the glass disk polishing method according to (7).

  According to the present invention, the upper end of the drive shaft is fitted into the driven hole of the disk-shaped torque transmission member, and the disk-shaped torque transmission member is rotated via the coupling mechanism provided at the height position near the upper polishing pad. By adopting a structure that transmits to the outer periphery of the upper surface plate, the horizontal force acting on the upper surface plate can be suppressed as much as possible, and the pendulum movement of the upper surface plate can be made very small compared to the existing machine. The parallelism between the polishing surface of the upper surface plate and the polishing surface of the lower surface plate can be ensured with high accuracy, and the inner circumference of the upper surface plate can be reduced in diameter, so that the overall size of the apparatus can be reduced. Is possible.

  Further, according to the present invention, the entire circumference of the upper polishing pad can be pressed against each upper surface of the plurality of glass disks with uniform pressure by the air pressure of the air bag and the weight of the upper surface plate, and polishing of the plurality of glass disks. Polishing accuracy can be increased by suppressing variation in amount.

  Further, according to the present invention, by setting the distance in the height direction from the polishing surface to the position where the rotational torque is transmitted to the upper surface plate to be smaller than 100 mm, the pendulum operation of the upper surface plate by the rotational torque transmission is greatly increased. Thus, the polishing accuracy of the polishing surface is stabilized, and variations in the polishing accuracy associated with the rotating operation of the upper surface plate when polishing a plurality of glass disks can be suppressed.

It is a front view which shows one Example of the glass disc grinding | polishing apparatus by this invention. It is a longitudinal cross-sectional view which shows typically the state which raised the upper surface plate unit. It is a longitudinal cross-sectional view which shows typically the state which lowered | hung the upper surface plate unit. It is a top view which shows the attachment state of the carrier mounted in the lower surface plate. It is a longitudinal cross-sectional view which expands and shows the cross section which follows the AA line in FIG. It is a longitudinal cross-sectional view which expands and shows the cross-section of an upper surface plate and a lower surface plate when lowering an upper surface plate unit. It is a longitudinal cross-sectional view which expands and shows the pressurization state by the pressurization mechanism at the time of a grinding | polishing process. It is a longitudinal cross-sectional view which shows the state before pressurizing an upper surface plate typically. It is a longitudinal cross-sectional view which shows the pressurization state of an upper surface plate typically. It is a top view which shows the connection mechanism which connects the outer periphery of an upper surface plate, and the outer periphery of a disk shaped torque transmission member. It is a side view which shows the connection mechanism which connects the outer periphery of an upper surface plate, and the outer periphery of a disk shaped torque transmission member. It is a front view which shows the connection mechanism which connects the outer periphery of an upper surface plate, and the outer periphery of a disk shaped torque transmission member. It is a front view which shows the stopper mechanism which regulates the separation distance of the outer periphery of an upper surface plate, and the outer periphery of a disk shaped torque transmission member. It is a sectional side view which shows the stopper mechanism which regulates the separation distance of the outer periphery of an upper surface plate, and the outer periphery of a disk shaped torque transmission member. It is a systematic diagram which shows the structure of an air pressure control system. It is a block diagram of a control system showing each device controlled by a control unit. It is a flowchart for demonstrating the control process of the grinding | polishing process which the control part 90 performs, and the procedure of the operation | work which an operator performs. It is a flowchart for demonstrating the procedure of the control process performed following the control process of FIG. 16A, and the operation | work which an operator performs.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a front view showing an embodiment of a glass disk polishing apparatus according to the present invention. As shown in FIG. 1, the glass disk polishing apparatus 10 is configured to simultaneously polish the upper and lower surfaces of a plurality of glass disks, and includes a base 20, a lower surface plate 30, an upper surface plate unit 40, The elevating mechanism 50 and the rotation transmission mechanism 60 are included. A lower surface plate 30 is rotatably supported on the upper portion of the base 20, and a surface plate drive motor as a drive unit described later is attached to the inside of the base 20.

  The lower surface plate 30 has a lower polishing pad for polishing the lower surfaces of a plurality of glass disks held by a carrier, as will be described later. Further, the upper surface plate unit 40 has an upper polishing pad that is disposed so as to face the upper surface of the lower surface plate 30 and that polishes the upper surfaces of a plurality of glass disks.

  The elevating mechanism 50 is supported by a gate-type frame 70 that stands above the base 20 and has an elevating cylinder device 52 that elevates and lowers the upper surface plate unit 40 when replacing the carrier. The lifting cylinder device 52 is attached to the center of the beam 72 of the frame 70 so as to extend and contract in the hanging direction. The piston rod 54 of the lifting / lowering cylinder device 52 extends downward, and a shaft member 58 that is fitted to the inner peripheral side of the bearing 56 is coupled to the tip of the piston rod 54. The bearing 56 rotatably supports the upper surface plate unit 40. Further, a rotary joint is provided below the shaft member 58.

  The suspension member 80 fitted to the outer peripheral side of the bearing 56 is attached so as to suspend the upper surface plate unit 40. Therefore, when the piston rod 54 of the lifting / lowering cylinder device 52 is driven upward or downward, the upper surface plate unit 40 connected to the piston rod 54 via the suspension member 80 is simultaneously driven to rise or lower. To do.

  Further, dress positioning stopper mechanisms 320 are provided on both sides of the lifting cylinder device 52 on the beam 72 of the frame 70. The dressing positioning stopper mechanism 320 positions the upper surface plate unit 40 at a position where it is raised when the dressing process for adjusting the surface of the polishing pad, which will be described later, is performed. The dress positioning stopper mechanism 320 includes a horizontal drive cylinder device 322 attached in the horizontal direction and a stopper plate 324 supported at the tip of the piston rod of the horizontal drive cylinder device 322. The stopper plate 324 is normally retracted to the outside of the lifting cylinder device 52, and is driven to the center side when performing dressing to position the piston rod 54 at a position moved upward by the thickness of the dressing carrier. .

  The glass disk polishing apparatus 10 includes a control unit 90 that controls the upper surface plate unit 40, the lifting mechanism 50, and the rotation transmission mechanism 60.

  FIG. 2A is a longitudinal sectional view schematically showing a state where the upper surface plate unit is raised. As shown in FIG. 2A, the upper surface plate unit 40 includes a disk-shaped torque transmission member 100, an upper surface plate 110, a pressurizing mechanism 120, a coupling mechanism 130, a polishing pad attaching / detaching unit 140, and a stopper mechanism 150. (Omitted in FIG. 2A).

  The upper surface plate unit 40 is lifted by the lifting cylinder device 52 at the time of carrier replacement or pad replacement and moves above the lower surface plate 30 (Za direction). In this raised state, the plurality of glass disks and carriers 160 that have been mounted on the upper surface of the lower surface plate 30 are removed, and another carrier 160 and an unpolished glass disk are mounted on the upper surface of the lower surface plate 30. Is possible.

  The rotation transmission mechanism 60 has a coupling portion 62 formed in a cylindrical shape at the upper end of the motor drive shaft 61 of the surface plate drive motor. The coupling portion 62 has a plurality of coupling pins 63 that fit into coupling holes 102 provided in the driven hole 101 of the disk-shaped torque transmission member 100 on the upper surface. The connecting pin 63 has a conical shape whose tip is easy to insert into the connecting hole 102. Further, when the upper surface plate unit 40 is lowered by the lifting cylinder device 52, the disk-shaped torque transmission member 100 is kept in a state in which the alignment marks provided in advance on the disk-shaped torque transmission member 100 and the coupling portion 62 are matched. By lowering, the relative positions of the connecting hole 102 and the connecting pin 63 can be matched.

  Furthermore, a horizontal direction correction mechanism 170 that corrects the horizontal position of the upper surface plate 110 is provided in the cylindrical portion 110 d on the inner peripheral side of the upper surface plate 110. The horizontal direction correcting mechanism 170 includes a plurality of contact members 172 that absorb horizontal force during polishing, and each contact member 172 includes a plurality of cylindrical portions 110d that extend in the axial direction from the inner peripheral side of the upper surface plate 110. It is provided at predetermined intervals in the place. Further, it is desirable that the mounting height position of the contact member 172 is close to the polishing surface.

  Each contact member 172 integrally includes an elastic portion made of soft silicon having a hardness of 30 ° to 40 ° and a low friction portion formed in a hemispherical shape that contacts the inner wall of the driven hole 101. It is a combined configuration. Further, in the horizontal direction correcting mechanism 170, the low friction portion of the contact member 172 provided on the outer periphery of the inner peripheral side cylindrical portion 110d of the upper surface plate 110 contacts the inner wall of the driven hole 101 of the disk-shaped torque transmission member 100. It is the structure to do. Therefore, the elastic portion of each contact member 172 absorbs the horizontal force between the disk-shaped torque transmission member 100 and the upper surface plate 110, and a low friction portion is provided at the contact portion of each contact member 172. Thus, the harmful frictional resistance during the pressurizing operation due to the force generated in the horizontal direction can be greatly reduced.

  FIG. 2B is a longitudinal sectional view schematically showing a state where the upper surface plate unit is lowered. As shown in FIG. 2B, by reducing the supply pressure P1 of compressed air to the lower chamber of the lifting cylinder device 52 (at this time, the upper chamber of the lifting cylinder device 52 is open to the atmosphere, P2 is atmospheric pressure), When the piston rod 54 of the lifting cylinder device 52 is driven downward (Zb direction) by the weight of the upper surface plate unit 40, the upper surface plate unit 40 is lowered together with the suspension member 80.

  The rotational torque of the surface plate drive motor provided on the base 20 is transmitted to the disk-shaped torque transmission member 100 via the connection pins 63 and the connection holes 102 that stand on the coupling portion 62. Further, since the rotation transmission mechanism 60 is configured such that each connection pin 63 and each connection hole 102 are fitted, a key groove and a key that are formed to extend in the axial direction as compared with a conventional key structure are provided. By preventing the vertical movement (movement that kneads up and down) associated with the fitting, the vertical component force is not generated. The upper surface plate 110 that performs the actual polishing operation is transmitted with rotational torque from the disk-shaped torque transmission member 100 via a coupling mechanism 130 provided on the outer peripheral edge.

  Since the disk-shaped torque transmitting member 100 and the upper surface plate 110 do not have a rigid coupling structure, the upper surface plate 110 is not affected by any force generated in the vertical direction or the horizontal direction on the polishing surface. No stress is generated between the disk-shaped torque transmitting member 100.

  In addition, the surface plate driving motor that rotationally drives the upper surface plate unit 40 is disposed inside the base 20 and is not provided on the frame 70. Therefore, the center of gravity of the entire apparatus is lowered to reduce the center of the apparatus during the polishing operation. In addition to suppressing vibration, the stability during the polishing operation is further enhanced.

  In FIG. 2B, the pressurizing mechanism 120 is in a non-pressurized state, and the polishing pad attaching / detaching unit 140 and the upper surface plate 110 abut on the upper surfaces of a plurality of glass disks placed on the lower surface plate 30 by their own weight. It is in a state.

  FIG. 3 is a plan view showing the carrier placed on the lower surface plate. As shown in FIG. 3, a plurality of carriers 160 are placed on the upper surface 31 of the lower surface plate 30. The carrier 160 is formed in a disk shape from a resin material thinner than the glass disk 200, and a large number of storage holes 161 for storing the glass disk 200 are provided concentrically. The large number of storage holes 161 are formed so as to hold the outer periphery of each of the stored glass disks 200 without any backlash. In this embodiment, a configuration in which five carriers 160 are arranged is shown as an example. However, the configuration is not limited to this, and five or more carriers 160 may be arranged according to the size (diameter) of the lower surface plate 30 and the carrier 160. good.

  A sun gear 32 is inserted from below into the rotation center hole of the upper surface 31 of the lower surface plate 30, and an inner gear 33 is provided at the outer peripheral inner edge of the upper surface 31 of the lower surface plate 30. In the carrier 160, a gear 162 formed on the outer periphery meshes with the sun gear 32 and the inner gear 33 of the lower surface plate 30. Therefore, as the lower platen 30 is driven to rotate, the carrier 160 rotates relative to the sun gear 32 in the circumferential direction and revolves in the circumferential direction of the sun gear 32 while rotating. Thereby, it becomes possible to make the thickness after polishing uniform by preventing deviation of the polishing amount of each glass disk 200 stored in each storage hole 161 of each carrier 160.

  FIG. 4 is a longitudinal sectional view schematically showing a section taken along line AA in FIG. As shown in FIG. 4, during the polishing process, the lower polishing pad 210 held on the upper surface 31 of the lower surface plate 30 is in contact with the lower surface of each glass disk 200 and is lowered to the polishing position by the lifting mechanism 50. The upper polishing pad 220 of the polishing pad attaching / detaching unit 140 held on the upper surface plate 110 is in contact with the upper surface of each glass disk 200. Therefore, in the glass disk polishing apparatus 10, the upper surface plate 110 and the lower surface plate 30 rotate relative to each other, so that the upper surface of each glass disk 200 held on the carrier 160 between the upper surface plate 110 and the lower surface plate 30 and It becomes possible to polish the lower surface simultaneously. The surfaces of the lower polishing pad 210 and the upper polishing pad 220 that are in contact with each glass disk 200 are polishing surfaces.

  Here, the configuration of the upper surface plate 110, the pressurizing mechanism 120, and the polishing pad attaching / detaching unit 140 for polishing each glass disk 200 stored in each storage hole 161 of each carrier 160 will be described.

  FIG. 5 is an enlarged longitudinal sectional view showing the cross-sectional structures of the upper surface plate and the lower surface plate when the upper surface plate unit is lowered. As shown in FIG. 5, the upper surface plate 110 is formed to be thinner than the existing upper surface plate and is made of an aluminum alloy that is lighter than existing iron plates, and thus is significantly lighter. . The material of the upper surface plate 110 is not limited to an aluminum alloy, but a material that is lighter than other irons and has high strength (for example, titanium, carbon fiber reinforced plastic (CFRP), etc.) is used. May be.

  The conventional upper surface plate is made of iron and may be deformed so that the peripheral edge of the polishing pad mounting surface facing the polishing surface is warped upward due to heat generated during polishing. On the other hand, since the upper surface plate 110 of this embodiment is made of an al alloy having a high thermal conductivity, heat generated on the polished surface is easily released. For this reason, the upper surface plate 110 has a structure in which the thickness in the height direction is reduced to reduce the thickness, and thermal deformation is unlikely to occur. In particular, the outer peripheral edge warps upward due to heat generation during the polishing process. It is prevented.

  On the upper surface side of the upper surface plate 110, a recess 111 for inserting the slurry supply tube and a pressure receiving plate 112 for closing the recess 111 are provided. In addition, a plurality of vacuum grooves 110 c for vacuum-sucking the polishing pad detaching unit 140 are provided on the lower surface 110 b of the upper surface plate 110. As the vacuum groove 110c, for example, a plurality of annular grooves concentrically formed on the lower surface 110b of the upper surface plate 110, or a plurality of radial shapes extending from the center of the lower surface 110b of the upper surface plate 110 toward the outer peripheral direction. Grooves are provided.

  Thus, the upper surface plate 110 is configured to vacuum-suck the polishing pad detachment unit 140 that receives polishing resistance during the polishing process to the lower surface 110b, so that the polishing pad detachment unit that holds the upper polishing pad 220 with vacuum suction turned off. 140 can be detached from the upper surface plate 110. Then, another polishing pad attaching / detaching unit 140 that holds the unused upper polishing pad 220 is attached to the upper surface plate 110. As a result, the pads can be replaced for each polishing pad detaching unit 140, so that the work time required for replacing the polishing pads of the glass disk polishing apparatus 10 can be shortened and the polishing pads can be replaced so as not to impede the operation of the polishing apparatus as much as possible. .

  Moreover, the upper surface 110a of the upper surface plate 110 is formed with a plurality of recesses 111 into which the slurry supply tubes are inserted. In addition, the recess 111 is provided with a hole 111a for supplying slurry to the polishing surface. Therefore, during the polishing process, it is possible to supply the slurry between the polishing pad desorption unit 140 and the glass disk 200. In addition, the used slurry that has passed from the polishing surface is recovered and reused.

  The pressure receiving plate 112 attached to the upper surface 110a of the upper surface plate 110 receives the pressing force of the air bag 121 by compressed air when pressurized. For example, a rubber plate and a metal plate are integrally overlapped with each other. It has a heavy structure.

  Above the upper surface plate 110, an air bag 121 constituting the pressurizing mechanism 120, a pressure base 122 that supports the air bag 121, a holding member 123 that holds the peripheral portion of the air bag 121, and air An elastic plate 124 fixed to the lower surface of the bag 121 is provided. The pressurized base 122 is provided with a plurality of air supply / exhaust holes 122 a for supplying and exhausting compressed air to and from the air bladder 121.

  The air bag 121 is formed in an annular shape, similar to the shape of the lower surface side of the disk-shaped torque transmission member 100. The air bladder 121 is made of, for example, an aromatic polyamide-based resin having high strength, airtightness, or flexibility, or a bellows-like rubber, and the inner and outer circumferences are held on the lower surface of the pressure base 122 by the holding member 123. Has been.

  The pressurizing base 122 has a larger diameter than the outer diameter of the air bladder 121 and a smaller inner diameter, and is formed in an annular shape like the air bladder 121. Further, the pressure base 122 is an annular plate made of a metal such as stainless steel, for example, and is disposed above the upper surface plate 110 so as to be opposed thereto.

  The holding member 123 is formed in an annular shape from a metal such as stainless steel, for example, and is attached so as to sandwich the outer peripheral edge portion and the inner peripheral edge portion of the air bag 121 between the pressure base 122. Moreover, the holding member 123 has an inclined surface 123a so as not to damage the air bladder 121 inflated by the compressed air. When compressed air is supplied between the lower surface of the pressurizing base 122 and the air bladder 121, the air bladder 121 is inflated toward the lower side of the pressurizing base 122, with a pressing force corresponding to the degree of inflation at that time. The entire circumference of the pressure receiving plate 112 positioned below is pressed evenly (the same pressure over the entire circumference).

  The elastic plate 124 provided on the lower surface of the air bladder 121 is formed in an annular shape corresponding to the lower surface of the pressure base 122 by, for example, elastic urethane resin or the like. And the elastic board 124 has the inclined surface 124a which inclines at the same angle so that it may oppose the inclined surface 123a of the holding member 123 in a peripheral part. The elastic plate 124 inflates the air bag 121 downward due to air pressure, and moves below the holding member 123 to contact the pressure receiving plate 112 and press the upper surface plate 110 downward.

  If the amount of downward displacement of the air bladder 121 is insufficient, a rubber plate 113 (indicated by a broken line in FIG. 5) is attached to the upper surface of the pressure receiving plate 112 to reduce the distance from the elastic plate 124. good.

  The polishing pad detaching unit 140 vacuum-adsorbed to the lower side of the upper surface plate 110 has an upper polishing pad 220 integrally attached to the lower surface side of the pad support base 142. The pad support base 142 is made of a material that is lighter than iron or the like, and may be an engineering plastic such as an aluminum alloy, CFRP (Carbon Fiber Reinforced Plastics), or vinyl chloride.

  FIG. 6 is an enlarged longitudinal sectional view showing a state of pressurization by the pressurization mechanism during the polishing process. As shown in FIG. 6, during the polishing process, compressed air is supplied between the air bladder 121 and the pressurized base 122 from the air supply / exhaust hole 122 a of the pressurized base 122, so that the air pressure in the air bladder 121 is increased. Increases to atmospheric pressure or higher, and the air bladder 121 inflates downward. Eventually, the elastic plate 124 fixed to the lower surface of the air bladder 121 is pressed against the pressure receiving plate 112 of the upper surface plate 110 by the air pressure determined by the amount of compressed air supplied to the inside of the air bladder 121.

  Then, the upper surface plate 110 brings the upper polishing pad 220 of the polishing pad detaching unit 140 into close contact with the upper surface of each glass disk 200 held by the carrier 160 by the resultant force of its own weight and the air pressure of the air bag 121. Since the air bag 121 is formed in an annular shape so as to face the entire upper surface of the upper surface plate 110, the entire upper surface of the upper surface plate 110 is pressed with the same force by air pressure. Since this pressing force acts evenly on the entire surface of the pressure receiving plate 112 of the upper surface plate 110, it acts as a polishing force that evenly polishes the upper surface of each glass disk 200 with which the upper polishing pad 220 abuts.

  By rotating the upper surface plate 110 and the lower surface plate 30 while maintaining the pressurized state by the air bag 121, the upper surface and the lower surface of each glass disk 200 are evenly polished. Further, the polishing amount of each glass disk 200 by the upper polishing pad 220 is adjusted to an arbitrary value by the pressing force of the air bladder 121, that is, the air pressure of the air bladder 121 and the polishing time. In this manner, the entire circumference of the upper polishing pad 220 can be pressed against each upper surface of the plurality of glass disks 200 with a uniform pressure by the air pressure of the air bladder 121, and variations in the polishing amount of the plurality of glass disks 200 can be suppressed. Polishing accuracy can be increased.

  When the upper polishing pad 220 is worn and the upper polishing pad 220 is worn down to the use limit, the entire polishing pad attaching / detaching unit 140 is replaced with a new one while the upper surface plate unit 40 is raised. The exchanging work of the polishing pad attaching / detaching unit 140 may be performed by releasing the vacuum suction by setting the inside of the vacuum groove 110c disposed on the lower surface 110b of the upper surface plate 110 to atmospheric pressure. As a result, the polishing pad detaching unit 140 can be easily separated from the upper surface plate 110.

  Then, the pad replacement operation is completed by vacuum-adsorbing the polishing pad attaching / detaching unit 140 having the unused upper polishing pad 220 to the lower surface 110b of the upper surface plate 110. When only the upper polishing pad 220 is replaced alone, a lot of labor is required for the work of removing the upper polishing pad 220. Therefore, the method of replacing the polishing pad attaching / detaching unit 140 for each upper polishing pad 220 alone is used alone. The replacement work can be performed in a shorter time than the case of replacement. Further, the upper polishing pad 220 of the polishing pad detaching unit 140 may be replaced by an operator who has free hands, or may be replaced between operations.

  Here, the pressurizing operation of the polishing pad detaching unit 140 by the pressurizing mechanism 120 will be described.

  FIG. 7 is a longitudinal sectional view schematically showing a state before pressurizing the upper surface plate. As shown in FIG. 7, by reducing the supply pressure P1 of compressed air to the lifting cylinder device 52 of the lifting mechanism 50 (at this time, the upper chamber of the lifting cylinder device 52 is open to the atmosphere, and P2 is atmospheric pressure. ) When the piston rod 52 is driven downward (Zb direction) by the weight of the upper surface plate unit 40, the upper surface plate unit 40 is lowered together with the suspension member 80. As a result, the upper surface plate 110, the polishing pad attaching / detaching unit 140 vacuum-adsorbed on the lower surface 110b, and the upper polishing pad 220 are lowered, and the upper polishing pad 220 is held on the upper surface of each glass disk 200 held by the carrier 160. Abut. When the upper polishing pad 220 is in contact with the upper surface of the glass disk 200, the weights of the upper surface plate 110 and the polishing pad attaching / detaching unit 140 act on the upper surface of each glass disk 200.

  On the other hand, when the upper surface plate unit 40 is further lowered, the air bag 121 comes into contact with the upper surface of the upper surface plate 110, and the weight of the disk-shaped torque transmission member 100 acts on the upper surface of each glass disk 200. The load on the glass disk 200 becomes excessive. Therefore, the height positions of the piston rod 54 and the shaft member 58 of the lifting cylinder device 52 are adjusted so that only the weights of the upper surface plate 110 and the polishing pad attaching / detaching unit 140 act.

  FIG. 8 is a vertical cross-sectional view schematically showing a pressurized state of the upper surface plate. As shown in FIG. 8, compressed air is supplied to the air bladder 121 during the polishing process. The air bladder 121 is inflated downward by the pressure of the compressed air supplied from the air supply / exhaust hole 122a of the pressurizing base 122, and presses the upper surface plate 110 downward. Due to the air pressure supplied to the air bag 121, the upper polishing pad 220 of the polishing pad detaching unit 140 vacuum-adsorbed to the lower surface 110 b of the upper surface plate 110 is pressed against the upper surface of each glass disk 200 held by the carrier 160. . At this time, the upper polishing pad 220 is pressed against the upper surface of each glass disk 200 by the resultant force of the weight of the upper surface plate 110 and the polishing pad attaching / detaching unit 140 and the pressure of the air bladder 121. Therefore, by adjusting the pressure of the air bladder 121, the polishing force of the upper polishing pad 220 on each glass disk 200 can be set to an appropriate value.

  At this time, compressed air is supplied to the upper chamber of the lifting cylinder device 52 to increase the upper chamber pressure P2, and the lower chamber pressure P1 is set to atmospheric pressure by opening the lower chamber of the lifting cylinder device 52 to the atmosphere. Thus, the reaction force from the air bladder 121 is received by the lifting cylinder device 52, and the pressing force of the air bladder 121 can be reliably transmitted to each glass disk 200.

  Since the pressing force of the air bag 121 acts uniformly on the entire circumference of the upper polishing pad 220, the upper polishing pad 220 disposed on the lower surface side of the upper surface plate 110 is disposed on the upper surface side of the lower surface plate 30. Polishing can be performed while maintaining a parallel state to the polishing surface of the side polishing pad 210.

  Here, the configuration of the connection mechanism 130 that connects the outer periphery of the upper surface plate 110 and the outer periphery of the disk-shaped torque transmission member 100 will be described.

  FIG. 9 is a plan view showing a connecting mechanism for connecting the outer periphery of the upper surface plate and the outer periphery of the disk-shaped torque transmission member. FIG. 10 is a side view showing a connecting mechanism that connects the outer periphery of the upper surface plate and the outer periphery of the disk-shaped torque transmission member. FIG. 11 is a front view showing the operation of the connecting mechanism that connects the outer periphery of the upper surface plate and the outer periphery of the disk-shaped torque transmission member. 10 and 11, the solid line indicates the operation state during the polishing process in which the upper surface plate unit 40 is lowered, and the two-dot chain line indicates the operation in which the upper surface plate unit 40 is lifted and separated from the lower surface plate 30. Indicates the state. 10 and 11, the position indicated by the two-dot chain line is a position where the coupling mechanism 130 is rotated in the vertical state. In practice, however, the upper surface plate 110 and the disc-like torque are caused by the stopper mechanism 150 described later. Since the separation distance from the transmission member 100 is restricted, the coupling mechanism 130 stops at a rotation angle slightly inclined downward from the horizontal state.

  As shown in FIGS. 9 to 11, the coupling mechanism 130 includes an upper bracket 131 fixed to the outer periphery of the disk-shaped torque transmission member 100, a ball bearing portion 132 coupled to the upper end side surface of the upper bracket 131, It has a lower bracket 133 fixed to the outer periphery of the surface plate 110, a ball bearing portion 134 connected to the upper end side surface of the lower bracket 133, and a connecting rod 135 mounted between the ball bearing portions 132, 134. . Each of the ball bearing portions 132 and 134 has a structure in which a sphere and a spherical concave portion are fitted, and has a universal joint structure that can rotate in any direction.

  Since the coupling mechanism 130 is configured such that ball bearing portions 132 and 134 coupled to both ends of the coupling rod 135 are rotatably supported by the upper bracket 131 and the lower bracket 133, the outer periphery of the upper surface plate 110 and the disk A predetermined angular range (shown by a two-dot chain line in FIGS. 10 and 11) from a horizontal state (a state shown by a solid line in FIGS. 9 and 11) according to a distance in the height direction from the outer periphery of the cylindrical torque transmission member 100. In a rotating state). That is, the connecting rod 135 approaches the horizontal direction as the distance between the outer periphery of the upper surface plate 110 and the outer periphery of the disk-shaped torque transmission member 100 decreases. The distance between the outer periphery of the upper surface plate 110 and the outer periphery of the disk-shaped torque transmission member 100 is determined when the upper surface plate 110 is seated on the upper surface of the glass disk 200 via the polishing pad attaching / detaching unit 140 (see FIG. 5). ), The height positions of the piston rod 54 and the shaft member 58 of the elevating cylinder device 50 are adjusted so that the holding member 123 and the pressure receiving plate 112 are spaced apart from each other.

  Further, during the polishing process, when air pressure is applied to the air bladder 121, the pressure applied to the polishing surface is caused by the lifting / lowering cylinder device via the disk-shaped torque transmission member 100, the suspension member 80, the shaft member 58, and the piston rod 54. 52, and a pressure P2 exceeding the reaction force is applied to the upper chamber of the lifting cylinder device 52, so that the interval between the holding member 123 and the pressure receiving plate 112, regardless of the air pressure of the air bag 121 during the polishing process, and The separation distance is kept constant.

  Further, during the polishing process, the rotational force on the outer periphery of the disk-shaped torque transmitting member 100 is efficiently transmitted to the outer periphery of the upper surface plate 110 via the connecting rod 135 of the connecting mechanism 130.

  That is, when the connecting mechanism 130 is in the polishing process, the connecting rod 135 extends in the tangential direction of the outer periphery of the disk-shaped torque transmission member 100 and the upper surface plate 110 (state shown by solid lines in FIGS. 9 and 11). The rotational torque of the outer periphery of the disk-shaped torque transmission member 100 can be transmitted to the outer periphery of the upper surface plate 110.

  As described above, each coupling mechanism 130 transmits the rotational torque of the disk-shaped torque transmitting member 100 to the upper surface plate 110 via the connecting rod 135 extending in the tangential direction of the outer periphery of the disk-shaped torque transmitting member 100 and the upper surface plate 110. Therefore, a large torque can be transmitted efficiently. Further, each coupling mechanism 130 is provided at a height position in the vicinity of the upper polishing pad 220, and the distance in the height direction from the polishing surface is suppressed to 100 mm or less, so that the upper polishing pad 220 is swung in the vertical direction. Such a force is difficult to act.

  Further, the coupling mechanism 130 of the present embodiment is provided at at least three locations on the outer circumference of the disk-shaped torque transmission member 100 and the upper surface plate 110. Therefore, the rotational torque of the disk-shaped torque transmitting member 100 is transmitted to the outer periphery of the upper surface plate 110 via the three connection mechanisms 130, but it is possible to provide three or more connection mechanisms 130.

  Here, the configuration of the stopper mechanism 150 that regulates the separation distance between the disk-shaped torque transmission member 100 and the upper surface plate 110 to a predetermined value or less will be described. The stopper mechanisms 150 are distributed at a plurality of locations on the inner and outer circumferences of the disk-shaped torque transmission member 100 and the upper surface plate 110, and are provided, for example, at four locations on the inner circumference side and six locations on the outer circumference side. ing.

  FIG. 12 is a front view showing a stopper mechanism that regulates a separation distance between the outer periphery of the upper surface plate and the outer periphery of the disk-shaped torque transmission member. FIG. 13 is a side sectional view showing a stopper mechanism that regulates a separation distance between the outer periphery of the upper surface plate and the outer periphery of the disk-shaped torque transmission member.

  As shown in FIGS. 12 and 13, the stopper mechanism 150 includes an upper bracket 151 fixed to the upper surface of the disk-shaped torque transmission member 100, a cylindrical stopper portion 152 of the upper bracket 151, and a cylindrical stopper portion 152. The inserted vertical rod 153, the flange 154 screwed to the upper end of the vertical rod 153, the biasing member 155 that biases the flange 154 upward, and the recess 110 e on the outer periphery of the upper surface plate 110 are fixed. And a lower bracket 156. When the upper surface plate 110 is seated on the glass disk 200 during polishing or when polishing is started, the urging member 155 made of a coil spring or the like is all of the weight of the upper surface plate 110 and the polishing pad attaching / detaching unit 140 on the glass disk 200. It is attached to reduce the load. The urging member 155 may be removed.

  The vertical rod 153 has a lower end fixed to the lower bracket 156 and an upper end standing in a vertical direction extending above the upper bracket 151. The upper bracket 151 is provided with an insertion hole 151a through which the vertical rod 153 is inserted. The insertion hole 151a communicates with a hollow hole 152a that penetrates the cylindrical stopper portion 152 in the axial direction (vertical direction).

  Further, during the polishing process, the upper surface plate unit 40 descends and stops at the position where the height is adjusted at the stroke end of the lifting / lowering cylinder device 52, so that the distance between the disk-shaped torque transmission member 100 and the upper surface plate 110 is increased. T becomes narrower. In this state, in the stopper mechanism 150, as the upper surface plate unit 40 is lowered, the gap S between the flange portion 154 and the upper end of the cylindrical stopper portion 152 is larger than that when the upper surface plate unit 40 is raised. Expanding.

  Therefore, when the upper surface plate unit 40 is raised at the time of carrier replacement or pad replacement, the separation distance T between the disk-shaped torque transmission member 100 whose outer peripheral side is connected by the connection mechanism 130 described above and the upper surface plate 110 is determined during polishing. It is further enlarged and is regulated by the gap S between the flange portion 154 of the stopper mechanism 150 and the upper end of the cylindrical stopper portion 152. At this time, when the urging member 155 is not attached to the stopper mechanism 150, the gap S becomes zero.

  Thus, since the operable range of the upper surface plate 110 suspended below the disk-shaped torque transmission member 100 via the coupling mechanism 130 is restricted by the stopper mechanism 150, the replacement operation of the glass disk 200 and the carrier 160 is performed. For example, as shown by a two-dot chain line in FIG. 10, the connecting rod 135 of the connecting mechanism 130 rotates in the hanging direction, and the upper surface plate 110 is suspended by the length of the connecting rod 135. And is not obstructed by the upper surface plate 110 in the suspended state.

  Here, the configuration of the pneumatic control system will be described.

  FIG. 14 is a system diagram showing the configuration of the pneumatic control system. As shown in FIG. 14, the upper surface plate 110 has a pressurization control line (compressed air supply unit) 230 for controlling the pressure of the air bladder 121 and a vacuum suction for controlling the adsorption / separation of the polishing pad desorption unit 140. Line 240 is connected.

  The pressurization control line 230 constitutes the pressurization mechanism 120 together with the air bladder 121 described above, and controls the pressure of the air bladder 121 by switching the supply or exhaust of compressed air to the air bladder 121. An air source 231, a filter regulator unit 232, a regulator 233, an electropneumatic regulator 234, a pressurization valve 235, an air release valve 236, and a pressurization pressure sensor 237 are arranged on the pressurization control line 230.

  The air source 231 is a supply source of compressed air generated by an air compressor or the like, and is formed by an air tank that stores compressed air or an air piping path that communicates with the air tank.

  The filter regulator unit 232, the regulator 233, and the electropneumatic regulator 234 are pressure setting means for stepwise reducing the air pressure supplied from the air source 231 to a predetermined pressure, and the pressure applied to the upper polishing pad 220 by the air bag 121 is reduced. The supplied pressure is adjusted so as to be an optimum value.

  The pressurization valve 235 is a normally closed two-port two-position solenoid valve, and when the solenoid is excited by a control signal from the control unit 90, the valve is switched from the closed state to the open state. That is, the pressurization valve 235 is pressurization switching means for supplying or stopping the supply of compressed air to the air bladder 121.

  Like the pressurizing valve 235, the air release valve 236 is a normally closed 2-port 2-position solenoid valve. When the solenoid is excited by a control signal from the control unit 90, the valve is changed from the closed state to the open state. Switch. That is, the atmosphere release valve 236 is an atmosphere release switching means for exhausting the compressed air of the air bladder 121 into the atmosphere.

  The pressurizing pressure sensor 237 outputs a pressure detection signal corresponding to the pressure in the pneumatic control line 230 to the control unit 90. Therefore, the control unit 90 recognizes the pressure state of the air bladder 121 in each process based on the pressure detection signal from the pressurization pressure sensor 237, and switches and controls the pressurization valve 235 and the atmosphere release valve 236 according to each process. .

  Further, the vacuum suction line 240 is connected so as to switch the suction / separation of the polishing pad desorption unit 140 by introducing a vacuum into the plurality of vacuum grooves 110c arranged on the lower surface 110b of the upper surface plate 110 or opening to the atmosphere.

  The vacuum adsorption line 240 includes a cooling water supply source 241, an on-off valve 242, a cooling water confirmation sensor 243, a vacuum pump 244, a vacuum gauge 245, a vacuum adsorption valve 246, an air release valve 247, an adsorption pressure sensor 248, and cooling water. A drain port 249 is arranged.

  The vacuum pump 244 is a water-sealed vacuum pump that holds the rotating part of the rotor (impeller) in an airtight manner with the cooling water supplied from the cooling water supply source 241, and sucks air in the piping of the vacuum adsorption line 240. And discharged together with the cooling water to the cooling water drain 249.

  The cooling water confirmation sensor 243 is a cooling water detection unit that detects cooling water supplied to the vacuum pump 244, and outputs a cooling water detection signal to the control unit 90.

  The vacuum gauge 245 is means for measuring the degree of vacuum of air that is decompressed by the vacuum pump 244.

  The vacuum suction valve 246 is a normally closed two-port two-position solenoid valve. When the solenoid is excited by a control signal from the control unit 90, the valve is switched from the closed state to the open state. That is, the controller 90 opens the vacuum suction valve 246 when vacuum-adsorbing the polishing pad desorption unit 140 to the lower surface 110b of the upper surface plate 110, and the vacuum groove 110c disposed on the lower surface 110b of the upper surface plate 110. Vacuum inside.

  Like the vacuum suction valve 246, the atmosphere release valve 247 is a normally closed two-port two-position solenoid valve. When the solenoid is excited by a control signal from the control unit 90, the valve is opened from the closed state. Switch to That is, the controller 90 opens the atmosphere release valve 247 when separating the polishing pad detaching unit 140 from the lower surface 110b of the upper surface plate 110, and the inside of the vacuum groove 110c disposed on the lower surface 110b of the upper surface plate 110 is opened. Set to atmospheric pressure.

  The suction pressure sensor 248 detects the pressure of the vacuum suction line 240 and outputs a pressure detection signal to the control unit 90. Therefore, the control unit 90 recognizes the pressure (vacuum or atmospheric release) of the vacuum suction line 240 from the suction pressure sensor 248 by the pressure detection signal, and determines the suction state (suction / separation) of the polishing pad desorption unit 140. It becomes possible.

  FIG. 15 is a block diagram of a control system showing each device controlled by the control unit. As shown in FIG. 15, the control unit 90 includes an elevating cylinder device 52, a pressurization valve 235, an atmospheric release valve 236, a pressurization pressure sensor 237, a vacuum pump 244, a vacuum adsorption valve 246, an atmospheric release valve 247, The suction pressure sensor 248, a surface plate drive motor (drive unit) 260 provided in the base 20, and a notification means 310 such as a monitor or a speaker are electrically connected to each other, and control for controlling each device. Generate a signal.

  Here, the control process of the polishing process executed by the control unit 90 and the procedure of the work performed by the operator will be described with reference to the flowcharts of FIGS. 16A and 16B.

  In S11 of FIG. 16A, the control unit 90 checks whether or not the power switch of the glass disk polishing apparatus 10 has been turned on. When the power switch is turned on, the process proceeds to S12 to start the vacuum pump 244, The vacuum suction valve 246 is opened to cause the polishing pad desorption unit 140 to be vacuum-sucked to the lower surface 110 b of the upper surface plate 110. Subsequently, in S13, by increasing the supply pressure P1 to the lower chamber of the lifting cylinder device 52 (at this time, the upper chamber of the lifting cylinder device 52 is opened to the atmosphere and P2 is atmospheric pressure), the piston rod 52 is moved. It drives upwards and raises the upper surface plate unit 40 with the suspension member 80 (refer FIG. 2A). Thereby, the upper surface plate unit 40 is separated above the lower surface plate 30.

  In next S 14, the operator sets the carrier 160 on the upper surface of the lower surface plate 30. Subsequently, in S <b> 15, the operator sets the glass disk 200 in each storage hole 161 of the carrier 160.

  In S <b> 16, the control unit 90 lowers the supply pressure P <b> 1 to the lower chamber of the lifting cylinder device 52 (at this time, the upper chamber of the lifting cylinder device 52 is opened to the atmosphere, P <b> 2 is atmospheric pressure), and the piston rod 52. Is driven downward (Zb direction) by the weight of the upper surface plate unit 40 (see FIG. 2B). Accordingly, when the upper surface plate unit 40 moves down to the stroke end of the cylinder 52 together with the suspension member 80 and the connection pin 63 of the connection portion 62 is fitted into the connection hole 102 of the disk-shaped torque transmission member 100, The upper polishing pad 220 of the polishing pad attaching / detaching unit 140 vacuum-adsorbed on the lower surface 110 b of the board 110 contacts the upper surface of each glass disk 200 held by the carrier 160. In a state where the upper polishing pad 220 is in contact with the glass disk 200, only the weights of the upper surface plate 110 and the upper surface plate unit 40 act on the upper surface of each glass disk 200 as a pressing force.

  In S <b> 17, the control unit 90 supplies the slurry to the upper surface plate unit 40. Further, in S18, the surface plate driving motor 260 is activated to transmit the motor driving force to the disk-shaped torque transmitting member 100 of the lower surface plate 30 and the upper surface plate unit 40.

  In S <b> 19, immediately after the start of polishing, the control unit 90 switches the pressurization valve 235 of the pressurization control line 230 to an open state and supplies compressed air to the air bladder 121 of the pressurization mechanism 120. When compressed air is supplied between the air bladder 121 and the pressurized base 122, the air bladder 121 expands downward, and an elastic plate 124 fixed to the lower surface of the air bladder 121 is attached to the pressure receiving plate 112 of the upper surface plate 110. Press (see FIG. 6). As a result, the upper polishing pad 220 attached to the lower surface of the polishing pad detaching unit 140 is brought into close contact with the upper surface of each glass disk 200 held by the carrier 160 by the pressure of the air bladder 121.

  When the connecting pin 63 of the connecting portion 62 is relatively fitted into the connecting hole 102 of the disc-shaped torque transmitting member 100 by the lowering operation of the upper surface plate unit 40, the disc-shaped torque transmitting member 100 is connected to the connecting hole 102 and the connecting pin. Rotational torque of the motor drive shaft 61 is transmitted through 63, and tangential rotational torque is efficiently transmitted from the outer periphery by the connecting mechanism 130 that connects the outer periphery of the disk-shaped torque transmitting member 100 and the outer periphery of the upper surface plate 110. . The distance in the height direction from the coupling mechanism 130 where the rotational torque is transmitted to the polishing surface of the upper polishing pad 220 is suppressed to, for example, 100 mm or less. Therefore, compared with the case where the distance in the height direction from the polishing surface to the suspension fulcrum of the upper surface plate in the existing glass disk polishing machine is 200 mm or more, it is caused by the pendulum movement with the rotation transmission portion as a fulcrum by the force in the horizontal direction. Generation of vertical force is greatly reduced.

  In addition, as described above, the drive force transmission path is arranged on the outer periphery of the upper surface plate 110, thereby reducing the diameter of the coupling portion 62 of the drive shaft 61 arranged at the center of rotation and the carrier 160. It is possible to make the entire apparatus capable of expanding the space necessary for mounting to the rotation center side compact.

  In the next S20, the polishing time (the surface plate rotation driving time) is counted. In S20, when the polishing time reaches a predetermined time set in advance, the process proceeds to S21. The predetermined time is empirically set according to the amount of polishing until the thickness dimension of the glass disk 200 reaches a specified value. For example, the hardness of the glass disk 200, the abrasive particle size of the pad, This time is set by comprehensively considering various conditions such as type, pad pressure, and surface plate rotation speed.

  In S20, when the polishing time reaches a predetermined time set in advance, the process proceeds to S21 in FIG. 16B, and the atmosphere release valve 236 of the pressurization control line 230 is switched to the valve open state (atmosphere release) before the polishing is completed. The compressed air inside the air bladder 121 of the pressurizing mechanism 120 is exhausted to reduce the pressure to the atmosphere. Therefore, the air bag 121 is displaced upward so as to be separated from the pressure receiving plate 112 of the upper surface plate 110 before the polishing is completed, and the pressurization by the air bag 121 is released (see FIGS. 5 and 7).

  In the next S22, the energization to the surface plate drive motor 260 is stopped to make the rotational torque zero. Subsequently, in S23, the slurry supply is stopped.

  In the next S24, the notification means 310 notifies the completion of the polishing by voice guidance or monitor display.

  Subsequently, the process proceeds to S25, where the supply pressure P1 to the lower chamber of the elevating cylinder device 52 is increased (at this time, the upper chamber of the elevating cylinder device 52 is opened to the atmosphere, P2 is atmospheric pressure), and the piston rod 54 Is moved upward to move the upper surface plate unit 40 above the lower surface plate 30 (Za direction) (see FIG. 2A). By such an upward movement of the upper surface plate unit 40, it becomes possible to take out a plurality of glass disks 200 and carriers 160 that have been polished.

  Further, when the upper surface plate unit 40 is lifted, each connecting rod 135 of the plurality of connecting mechanisms 130 that connects between the outer periphery of the upper surface plate 110 and the outer periphery of the disk-shaped torque transmission member 100 is rotated. Therefore, the upper surface plate 110 is displaced below the disk-shaped torque transmission member 100 (see FIGS. 10 and 11). However, in the process in which the upper surface plate unit 40 moves upward, the flange 154 of the stopper mechanism 150 is regulated by abutting against the upper end of the cylindrical stopper 152, so that the connecting rod 135 of the connecting mechanism 130 is in a substantially horizontal state. You can move up and down while keeping Therefore, the work for removing the glass disk 200 and the carrier 160 is not hindered by the upper surface plate 110 suspended by the coupling mechanism 130.

  In next S <b> 26, the operator takes out the carrier 160 from the lower surface plate 30. Subsequently, in S <b> 27, the operator takes out all the polished glass disks 200 from the lower surface plate 30.

  In the next S28, the operator determines whether the lower polishing pad 210 and the upper polishing pad 220 are clogged, and confirms whether or not the pad needs to be replaced. The pad replacement due to the clogging of the lower polishing pad 210 and the upper polishing pad 220 can be determined by, for example, an accumulated value of polishing time, the number of polishing steps, or measurement of pad groove depth by an operator. It becomes possible.

  Further, when the pad replacement is unnecessary, the operator confirms whether or not dressing processing of the lower polishing pad 210 and the upper polishing pad 220 is necessary in S29. If dressing is unnecessary, the operator confirms whether or not polishing is continued in S30. If the polishing is continued in S30, the process returns to S13 described above, and the procedures after S13 are repeated.

  When finishing the polishing, the process proceeds to S31, and the operator turns off the power switch, so that the controller 90 turns off the power to the vacuum pump 244 and puts the vacuum pump 244 in a stopped state.

  In S28, when it is determined that the lower polishing pad 210 and the upper polishing pad 220 are clogged, the operator selects whether pad replacement or dressing is necessary. If it is determined that the pad needs to be replaced, the process proceeds to S32 where the atmosphere release valve 247 of the vacuum suction line 240 is opened and the vacuum suction valve 246 is closed.

  In the next S33, the operator separates and removes the polishing pad attaching / detaching unit 140 from the upper surface plate 110. Subsequently, in S <b> 34, the operator removes the upper polishing pad 220 from the pad support base 142 of the polishing pad attaching / detaching unit 140. Then, a new upper polishing pad 220 is attached to the lower surface of the pad support base 142. As described above, the upper polishing pad 220 can be replaced relatively easily with the polishing pad attaching / detaching unit 140 removed from the upper surface plate 110. Further, the lower polishing pad 210 mounted on the lower surface plate 30 can also be replaced.

  Subsequently, in S <b> 35, the operator attaches the polishing pad detaching unit 140 with the new upper polishing pad 220 attached to the lower surface 110 b of the upper surface plate 110. Then, the air release valve 247 of the vacuum suction line 240 is closed and the vacuum suction valve 246 is opened. As a result, the replaced new polishing pad attaching / detaching unit 140 is attracted to the lower surface 110 b of the upper surface plate 110. Thereafter, the process proceeds to S36, and the worker performs pad dressing processing on the lower polishing pad 210 and the upper polishing pad 220. That is, after the polishing pad attaching / detaching unit 140 is raised by the lifting cylinder device 52, the dress carrier is set above the lower surface plate 30, and the upper surface plate 110 and the polishing pad attaching / detaching unit 140 are lowered to the dress height position. . At this time, the lowering position of the piston rod 54 of the lifting cylinder device 52 is regulated by the stopper plate 324 of the dress positioning stopper mechanism 320 (see FIG. 1), and the upper surface plate unit 40 is raised by the thickness of the dress carrier. It is positioned at the position. A diamond dresser is attached to the dress carrier, and the pad surfaces of the lower polishing pad 210 and the upper polishing pad 220 are adjusted by the diamond dresser.

Then, a pad dressing process is performed to remove polishing powder or the like adhering to the surfaces of the lower polishing pad 210 and the upper polishing pad 220 or to sharpen the pads. When the pad dressing process ends, the polishing pad desorption unit 140 is raised by the lifting cylinder device 52 to remove the dress carrier.
Thereafter, the process returns to the above-described process of S13, and the processes after S13 are repeated.

  Also, if it is determined in S29 that the dressing process of the lower polishing pad 210 and the upper polishing pad 220 is necessary, the process proceeds to S36 described above, and the operator moves the lower polishing pad 210 and the upper polishing pad 140 in the polishing pad detaching unit 140. The pad 220 is subjected to a pad dress process. Thereafter, the process returns to the above-described process of S13, and the processes after S13 are repeated.

  As described above, according to the glass disk polishing apparatus 10, the connecting pin 63 at the upper end of the motor drive shaft 61 is fitted into each connecting hole 102 of the disk-shaped torque transmission member 100, so that the rotational torque can be reduced. The upper platen 110 that actually transmits and contributes to the disk 100 is structurally cut off from the disk-shaped torque transmission member 100, and the disk-shaped torque transmission member via each coupling mechanism 130 disposed on the outer periphery. Rotational torque is transmitted from 100 to the upper surface plate 110.

  In addition, the distance in the height direction from the polishing surface of the coupling mechanism 130 is suppressed to 100 mm or less, and compared with the case where the upper platen suspension height is 200 mm or more above the polishing surface as in the existing apparatus. Thus, generation of vertical force due to pendulum motion with the rotation transmission portion due to horizontal force as a fulcrum is greatly reduced.

  Accordingly, the pendulum operation of the upper surface plate 110 is suppressed, so that the polishing accuracy of the polishing surface is stabilized, and the pressure of the polishing surface is made uniform by the air pressure of the air bag 121, and the plurality of glass disks 200 are polished. Variation in polishing accuracy associated with the rotation operation of the upper surface plate 110 can be suppressed.

  Accordingly, the parallelism between the polished surface of the upper surface plate 110 and the polished surface of the lower surface plate 30 can be ensured with high accuracy, and the upper surface is connected via the coupling mechanism 130 disposed on the outer periphery of the disk-shaped torque transmission member 100. Since the rotation from the motor drive shaft 31 is transmitted to the outer periphery of the surface plate 110, the inner periphery of the upper surface plate 110 can be reduced in diameter, and the overall size of the apparatus can be reduced.

Although this application has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention.
This application is based on a Japanese patent application filed on June 24, 2009 (Japanese Patent Application No. 2009-150312), the contents of which are incorporated herein by reference.

  In the above embodiment, the description has been given by taking as an example a polishing apparatus for polishing a glass disk for a magnetic disk. However, the present invention is not limited to this, and the present invention is also applied to polishing a glass disk used for other purposes. Of course you can.

  Further, the number of glass disks and the number of carriers placed on the lower surface plate are not limited to those in the above embodiment, and any number may be used as long as a plurality of glass disks can be simultaneously polished in one polishing process. .

Further, in the above-described embodiment, an example in which the upper surface plate unit is moved up and down using an air cylinder is illustrated. However, the present invention is not limited to this, and a structure in which the upper surface plate unit is moved up and down using driving means other than the air cylinder is also used. Of course it is good.
Generally, the manufacturing process of the glass substrate for magnetic recording media and the magnetic disk includes the following processes. (1) A glass base substrate formed by a float method, a fusion method, or a press molding method is processed into a disk (disk) shape, and then chamfered to the inner peripheral side surface and the outer peripheral side surface. (2) Grinding is performed on the upper and lower main planes of the glass substrate. (3) End face polishing is performed on the inner and outer peripheral side surfaces and chamfered portions of the glass substrate. (4) Polish the upper and lower main planes of the glass substrate. The polishing step may be only primary polishing, primary polishing and secondary polishing (polishing using finer abrasive grains than primary polishing) may be performed, and tertiary polishing (secondary polishing after secondary polishing). Polishing using finer abrasive grains) may be performed. (5) Precision cleaning of the glass substrate is performed to obtain a glass substrate for a magnetic recording medium. (6) A thin film such as a magnetic layer is formed on a glass substrate for a magnetic recording medium to manufacture a magnetic disk.
In the manufacturing process of the glass substrate for magnetic recording medium and the magnetic disk, glass substrate cleaning (inter-process cleaning) or etching of the glass substrate surface (inter-process etching) may be performed between the processes. Furthermore, when high mechanical strength is required for the glass substrate for magnetic recording media, a strengthening step (for example, a chemical strengthening step) for forming a reinforcing layer on the surface layer of the glass substrate is performed before the polishing step, after the polishing step, or the polishing step. You may carry out between.
In the present invention, the glass substrate for a magnetic recording medium may be amorphous glass, crystallized glass, or tempered glass (for example, chemically tempered glass) having a tempered layer on the surface layer of the glass substrate. Moreover, the glass base substrate of the glass substrate of the present invention may be made by a float method, may be made by a fusion method, or may be made by a press molding method.
The present invention relates to (4) a step of polishing the upper and lower main planes of a glass substrate, and relates to polishing of a glass substrate for a magnetic recording medium.

DESCRIPTION OF SYMBOLS 10 Glass disk grinding | polishing apparatus 20 Base 30 Lower surface plate 31 Upper surface 32 Sun gear 33 Inner gear 40 Upper surface plate unit 50 Lifting mechanism 52 Lifting cylinder device 54 Piston rod 56 Bearing 58 Shaft member 60 Rotation transmission mechanism 61 Motor drive shaft 62 Coupling part 63 Connecting pin 70 Frame 80 Suspended member 90 Control unit 100 Disk-shaped torque transmission member 101 Driven hole 102 Connection hole 110 Upper surface plate 110a Upper surface 110b Lower surface 110c Vacuum groove 111 Recess 112 Pressure receiving plate 120 Pressure mechanism 121 Air bag 122 Addition Pressure base 122a Air supply / discharge hole 123 Holding member 124 Elastic plate 130 Connecting mechanism 131 Upper bracket 132, 134 Ball bearing portion 135 Connecting rod 140 Polishing pad attaching / detaching unit 142 Pad support base 150 Stopper mechanism 151 Upper bracket 151a Insertion Hole 152 Cylindrical stopper portion 152a Hollow hole 153 Vertical rod 154 Eave portion 155 Biasing member 156 Lower bracket 160 Carrier 161 Storage hole 172 Contact member 170 Horizontal direction correction mechanism 200 Glass disk 210 Lower polishing pad 220 Upper polishing pad 230 Pressurization control line 231 Air source 232 Filter regulator unit 233 Regulator 234 Electropneumatic regulator 235 Pressurization valve 236 Atmospheric release valve 237 Pressurization pressure sensor 240 Vacuum adsorption line 241 Cooling water supply source 242 On-off valve 243 Cooling water confirmation sensor 244 Vacuum pump 245 Vacuum gauge 246 Vacuum suction valve 247 Atmospheric release valve 248 Suction pressure sensor 249 Cooling water drain port 310 Notification means 320 Dress positioning stopper mechanism 322 Horizontal drive cylinder device 324 Stop Board

Claims (9)

The base,
A lower surface plate having a lower polishing pad that is supported by the base and polishes the lower surfaces of a plurality of glass disks held by a carrier;
An upper surface plate having an upper polishing pad disposed on the lower surface plate so as to face the upper surfaces of the plurality of glass disks;
An elevating mechanism supported above the base and elevating the upper surface plate;
A drive unit provided on the base;
The upper polishing pad is brought into contact with the upper surfaces of the plurality of glass disks by the lowering operation of the elevating mechanism, and the upper surface plate is lowered with the lower surfaces of the plurality of glass disks in contact with the lower polishing pads. In a glass disk polishing apparatus having a rotation transmission mechanism that transmits a driving force of the driving unit so as to rotate relative to a board,
The rotation transmission mechanism is
A drive shaft extending in a vertical direction from the drive unit and transmitting a rotational torque of the drive unit;
A disk-shaped torque transmission member having a driven hole into which the upper end of the drive shaft is fitted, and disposed above the upper surface plate;
A connection mechanism provided at a height position near the upper polishing pad, and connecting between an outer periphery of the upper surface plate and an outer periphery of the disk-shaped torque transmission member;
A glass disk polishing apparatus, wherein the rotation of the disk-shaped torque transmitting member is transmitted to the outer periphery of the upper surface plate through the coupling mechanism.   The glass disk polishing apparatus according to claim 1, wherein the upper surface plate is formed of any one of an aluminum alloy, titanium, and carbon fiber reinforced plastic.   2. The glass disk polishing apparatus according to claim 1, wherein the disk-shaped torque transmission member includes a pressure unit that presses the entire upper surface of the upper surface plate downward. The pressurizing part is
An air bag formed in an annular shape so as to press the entire upper surface of the upper surface plate;
A compressed air supply unit for supplying compressed air to the air bag,
The said upper surface plate presses the said upper side polishing pad with uniform pressure on each upper surface of these glass discs with the air pressure of the air bag filled with dead weight and compressed air. Glass disk polishing equipment.   The compressed air supply unit supplies and pressurizes compressed air to the air bag immediately after the start of polishing by the upper surface plate, and exhausts and depressurizes air in the air bag before completion of polishing by the upper surface plate. The glass disk polishing apparatus according to claim 4.   The distance in the height direction between the polishing surface of the upper polishing pad and the rotational torque transmission position for transmitting rotational torque to the upper surface plate via the coupling mechanism is set to be 100 mm or less. The glass disk grinding | polishing apparatus of any one of Claims 1 thru | or 4. The upper surface plate holding the upper polishing pad is lowered to contact the upper surface of the plurality of glass disks held by the carrier, and the lower surface of the plurality of glass disks held by the lower surface plate In the glass disk polishing method of polishing the upper surface and the lower surface of the plurality of glass disks by rotating the upper surface plate relative to the lower surface plate in contact with the polishing pad,
Lowering the upper surface plate and fitting a driven hole of a disk-shaped torque transmission member connected to the upper side of the upper surface plate to the upper end of the drive shaft;
Compressed air is supplied to an air bag disposed between the disk-shaped torque transmitting member and the upper surface plate, and a uniform pressure is applied to the entire circumference of the upper polishing pad by the air pressure of the air bag and the weight of the upper surface plate. And pressing each upper surface of the plurality of glass disks, and pressing the lower surface of the plurality of glass disks against the lower polishing pad,
The rotation of the disk-shaped torque transmission member is transmitted to the outer periphery of the upper surface plate via a connection mechanism that connects the outer periphery of the disk-shaped torque transmission member and the outer surface of the upper surface plate, and the upper polishing pad is moved to the lower surface. Polishing the upper and lower surfaces of the plurality of glass disks by rotating relative to the side polishing pad;
After the polishing of the upper and lower surfaces of the plurality of glass disks is completed, the air in the air bag is exhausted, and the upper polishing plate is raised to move the upper polishing pad above the plurality of glass disks. When,
A glass disk polishing method comprising: In a method for producing a glass substrate for a magnetic recording medium, comprising: a shape imparting step of forming a glass substrate having a plate shape into a disk shape; a polishing step of a main plane of the glass substrate; and a cleaning step of the glass substrate.
The said grinding | polishing process is a manufacturing method of the glass substrate for magnetic recording media which grind | polishes both the main surfaces of a glass substrate simultaneously using the glass disc grinding | polishing apparatus of any one of Claims 1-6. In a method for producing a glass substrate for a magnetic recording medium, comprising: a shape imparting step of forming a glass substrate having a plate shape into a disk shape; a polishing step of a main plane of the glass substrate; and a cleaning step of the glass substrate.
The said grinding | polishing process is a manufacturing method of the glass substrate for magnetic recording media which grind | polishes both main surfaces of a glass substrate simultaneously with the glass disk grinding | polishing method of Claim 7.

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