JP4239129B2 - Plate-shaped body polishing apparatus and polishing pad truing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a plate-like body polishing apparatus, and more particularly to a polishing apparatus for manufacturing a glass substrate for a liquid crystal display , and a truing method for a polishing pad provided therein.
[0002]
[Prior art]
6 and 7 are schematic configuration diagrams of a continuous polishing apparatus for manufacturing a glass substrate for liquid crystal display. 6 shows an apparatus for polishing a glass plate by rotating a surface plate provided with a circular polishing pad, and FIG. 7 shows an apparatus for polishing a glass plate by swinging the surface plate provided with a rectangular polishing pad. .
[0003]
In FIGS. 6 and 7, the polishing apparatuses 1 and 1 ′ fix the glass plate 2 as a glass substrate with a urethane foam table pad 4 provided on the work surface plate 3, and convey it by the conveying means 5. However, the glass plate 2 is polished little by little by a plurality of polishing apparatuses 1, 1 ′ installed in the transfer line to manufacture a glass substrate having a predetermined thickness.
[0004]
The polishing apparatus 1 is configured by fixing an aluminum plate 7 on which a polishing pad 6 is supported to a polishing surface plate 8 as shown in FIG. When the glass plate 2 fixed to the table pad 4 (see FIG. 8) on the work surface plate 3 (see FIG. 6) is conveyed below the polishing apparatus 1, and when the glass plate 2 passes through the polishing apparatus 1, Polishing is performed by the polishing pad 6.
[0005]
[Problems to be solved by the invention]
However, the continuous polishing apparatus 1 is an apparatus in which the glass plate 2 enters from the outside of the polishing pad 6 and has a characteristic that pressure is concentrated on the end portion 6A of the polishing pad 6. Therefore, the glass plate that has passed through the polishing pad 6 is used. There was a problem that uneven polishing occurred on the polished surface of No. 2.
[0006]
The present invention has been made in view of such circumstances, and polishing of a plate-like body that can alleviate the pressure concentration generated at the end of the polishing pad and suppress uneven polishing generated on the polishing surface of the plate-like body. An object is to provide an apparatus.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a polishing pad on a polishing surface plate, presses the polishing pad against the plate-like body, and moves the plate-like body relative to each other by moving the polishing pad and the plate-like body relative to each other. In a polishing apparatus for polishing , an expansion / contraction means is provided between an end of the polishing surface plate and the polishing pad, and the end of the polishing pad is pressurized by expanding / contracting the expansion / contraction means. The expansion / contraction means is expanded when the polishing pad is surfaced with a truing grindstone, and the end of the polishing pad is ground with a truing grindstone .
[0010]
According to the onset bright, pressed against the polishing pad to the plate-like body, so is pressed to shrink at the end of the polishing pad deflating means, the ends of the polishing pad to escape from the plate-like body. As a result, the pressure concentration generated at the end of the polishing pad is alleviated, so that polishing unevenness generated in the plate-like body can be suppressed.
[0011]
The invention according to claim 2 applies an air bag as the inflating / contracting means, and the air bag inflates only by supplying air, so that the inflating / contracting means can be configured with a simple structure. .
In the invention described in claim 3, the plate-like body is a glass substrate for liquid crystal display.
According to a fourth aspect of the present invention, a polishing pad is provided on the polishing surface plate, the polishing pad is pressed against the plate-like body, and the plate-like body is polished by relatively moving the polishing pad and the plate-like body. A polishing pad truing method in a polishing apparatus, wherein an expansion / contraction means is provided between an end portion of the polishing surface plate and the polishing pad, and the expansion / contraction means is expanded and contracted to polish the polishing pad. The pressurization of the end of the pad is made controllable, and the expansion / contraction means expands when the polishing pad is chamfered with a truing grindstone, and the end of the polishing pad is ground with a truing grindstone. A polishing pad truing method in a polishing apparatus for polishing a plate-like body.
[0012]
According to the onset bright, when put face polishing pad truing grindstone, pressurizing the end portion of the polishing pad to inflate the inflation and deflation means, by pressing the end portion in the truing grindstone for grinding. As a result, the surface-exposed polishing pad is satisfactorily surfaced without any conventional protrusions. Therefore, the polishing accuracy of the plate-like body can be improved.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
A preferred embodiment of a plate-like body polishing apparatus according to the present invention will be described below in detail with reference to the accompanying drawings.
[0014]
The polishing apparatus according to the first embodiment cuts off the end of the polishing surface plate 8 corresponding to the position of the end 6A of the polishing pad 6 as shown in FIG. According to such a polishing apparatus, since the end portion 6A of the polishing pad 6 escapes to the space portion 9 formed by cutting the end portion of the polishing surface plate 8 due to elastic deformation of the aluminum plate 7, the pressure concentration is relieved. Uneven polishing can be suppressed.
[0015]
However, in the polishing apparatus shown in FIG. 1, when the polishing pad 6 is pressed against the truing grindstone to face the end, the end 6A of the polishing pad 6 escapes from the truing grindstone, so that the end 6A is not chamfered. However, there was a problem that the escape returned after truing and remained as a projection as shown in FIG.
[0016]
FIG. 3 is a cross-sectional view illustrating a configuration of the polishing apparatus 10 according to the second embodiment. The polishing apparatus 10 is an apparatus applied to a continuous polishing apparatus for glass substrates for liquid crystal displays, and a plurality of polishing apparatuses 10 are installed along a glass plate conveyance line (not shown).
[0017]
The polishing apparatus 10 is mainly composed of a support surface plate 12, a polishing surface plate 14, a polishing pad 16, an aluminum plate 17, an air bag (expansion / contraction means) 18, and the like. An upper end shaft portion 12A of the support surface plate 12 is connected to a drive shaft of a motor (not shown), and is rotated at a predetermined rotational speed by a rotational driving force from the motor. The support surface plate 12, the polishing surface plate 14, and the aluminum plate 17 are provided with a slurry supply path 13 for supplying a polishing liquid (slurry) to the polishing pad 16.
[0018]
The polishing surface plate 14 is a cast iron high-rigidity structure, and its surface shape is formed in a circular or rectangular shape. In the present embodiment, the polishing surface plate 14 will be described as a circular shape.
[0019]
A plurality of air springs 20, 20... Are arranged between the support surface 12 and the polishing surface 14. The air spring 20 is connected to an air pump through an air passage 22 formed in the support surface plate 12, a pressure adjusting device, and a rotary joint (not shown). Further, the supporting surface plate 12 and the polishing surface plate 14 are connected via a plurality of laminated rubbers 24, 24.
[0020]
On the other hand, the airbag 18 is disposed in a groove 26 formed on the outer periphery of the end of the lower surface of the polishing surface plate 14. The airbag 18 is formed of a single rubber sheet formed in a substantially ring shape. As shown in FIG. 4, the outer peripheral portion 18 </ b> A and the inner peripheral portion 18 </ b> B of the airbag 18 are sealed by ring-shaped packings 32 and 34 fixed to the polishing surface plate 14 with bolts 28 and 30.
[0021]
Further, an air passage 36 is formed in the outer peripheral portion of the polishing surface plate 14 so as to communicate with the space 19 between the airbag 18 and the groove 26. The air passage 36 is connected to the air passage 22 via a valve 38 and a pressure adjusting device as shown in FIG. Therefore, when the valve 38 is opened, the compressed air from the air pump is supplied to the space 19 in FIG. 4 through the rotary joint and the air passage 36. As a result, the airbag 18 is inflated, so that the end of the polishing pad 16 supported by the aluminum plate 17 is pressed downward and elastically deformed downward.
[0022]
Next, the operation of the polishing apparatus 10 configured as described above will be described.
[0023]
First, at the time of polishing the glass plate, the valve 38 is closed so that compressed air is not supplied to the air bag 18, or the compressed air pressure is lower than when the valve 38 is opened and the compressed air pressure is chamfered with a truing grindstone. Maintain a suitably selected pressure. When the polishing pad 16 is pressed against the glass plate in this state, the airbag 18 is pressed against the end of the polishing pad 16 and contracts, so that the end of the polishing pad 16 escapes from the glass plate. Thereby, since the pressure concentration generated at the end of the polishing pad 16 is alleviated, polishing unevenness generated in the glass plate can be suppressed.
[0024]
Next, when the polishing pad 16 is chamfered with a truing grindstone, the valve 38 is opened and the airbag 18 is inflated as shown in FIG. 5A, or the valve 38 is opened during polishing as described above. When left open, it is kept at a suitably selected pressure that is higher than the pressure selected above. Thus, the end portion 16A of the polishing pad 16 is pressed together with the aluminum plate 17 by the air bag 18, and the end portion 16A is pressed against the truing grindstone 40 of FIG. Therefore, the protrusion 16 as in the prior art does not occur on the end portion 16A of the polished polishing pad 16, and the R surface 16B as shown in FIG.
[0025]
When polishing of the glass plate is continued with the polishing pad 16 thus surfaced, the end surface 16A of the polishing pad 16 is formed with the R surface 16B, so the air bag 18 does not need to contract. The pressure concentration generated at the end 16A is alleviated. Therefore, the polishing accuracy of the glass plate is improved.
[0026]
In the present embodiment, since the airbag 18 that is inflated simply by supplying air is applied as the inflating / contracting means, the inflating / contracting means can be configured with a simple structure.
[0027]
In the present embodiment, the airbag 18 is applied as the expansion / contraction means. However, instead of the airbag 18, an expansion / contraction means such as a piezoelectric element is applied, and the expansion operation is performed when the polishing pad 16 is truing. You may make it make it.
[0028]
【The invention's effect】
As described above, according to the polishing apparatus for a plate-like body according to the present invention, a space part into which the end of the polishing pad escapes is formed between the end of the polishing surface plate and the end of the polishing pad, At the time of polishing the shaped body, the end of the polishing pad escapes into the space, so that the pressure concentration is alleviated and polishing unevenness can be suppressed.
[0029]
In addition, according to the present invention, the expansion / contraction means is provided between the end portion of the support surface plate and the polishing pad, and the end portion of the polishing pad can be pressurized by expanding the expansion / contraction means. Since it is configured, the pressure concentration generated at the end of the polishing pad due to the contracting action of the expansion / contraction means can be relieved, and the expansion / contraction means is expanded and polished by grinding the end of the polishing pad with a truing grindstone. The pad can be surfaced satisfactorily.
[0030]
In the present invention, since the airbag is applied as the expansion / contraction means, the expansion / contraction means can be configured with a simple structure.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram in which pressure is prevented from being concentrated by lowering the rigidity of an end portion of a supporting surface plate. FIG. 2 is an enlarged cross-sectional view of a main part of a polishing pad after truing. FIG. 3 is a structure of a polishing apparatus according to an embodiment. FIG. 4 is an enlarged cross-sectional view of the main part of an air bag provided in the polishing apparatus of FIG. 3. FIG. 5 is a transition diagram showing a truing method of the polishing pad by the air bag. Schematic diagram of the continuous polishing apparatus used. [Fig. 7] Schematic diagram of the continuous polishing apparatus using a rectangular polishing pad. [Fig. 8] An explanatory diagram showing the state of glass plate polishing by a conventional polishing apparatus.
6, 16 ... Polishing pad, 8, 14 ... Polishing surface plate, 9 ... Space part, 10 ... Polishing device, 12 ... Support surface plate, 18 ... Air bag (expansion / contraction means), 20 ... Air spring, 40 ... For truing Whetstone

Claims (4)

In a polishing apparatus for providing a polishing pad on a polishing platen, pressing the polishing pad against a plate-like body, and polishing the plate-like body by relatively moving the polishing pad and the plate-like body,
By providing expansion / contraction means that can freely expand and contract between the end of the polishing surface plate and the polishing pad, by allowing the expansion / contraction means to expand and contract, pressurization of the end of the polishing pad can be controlled ,
The expansion / contraction means is expanded when the polishing pad is chamfered with a truing grindstone, and an end portion of the polishing pad is ground with a truing grindstone . The plate-like body polishing apparatus according to claim 1 , wherein the expansion / contraction means is an air bag. The plate-like body polishing apparatus according to claim 1 or 2, wherein the plate-like body is a glass substrate for a liquid crystal display. A polishing pad truing method in a polishing apparatus in which a polishing pad is provided on a polishing platen, the polishing pad is pressed against a plate-like body, and the polishing pad and the plate-like body are moved relative to each other to polish the plate-like body. And
  By providing expansion / contraction means that can be expanded and contracted between an end portion of the polishing surface plate and the polishing pad, by allowing the expansion / contraction means to expand and contract, pressurization of the end portion of the polishing pad can be controlled,
  The expansion / contraction means expands when the polishing pad is chamfered with a truing grindstone, and grinds the end of the polishing pad with a truing grindstone. Truing method.

Images