JP2001087998A - Method and device for grinding plate glass - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and device for grinding a plate glass capable of grinding the peripheral edge of plate glass at a high speed. SOLUTION: This grinding device for plate glass 4 performs grinding in such a condition that the peripheral edge of the plate glass 4 is abutted to a concave grinding surface 1a provided at the periphery of a rotary whetstone 1 approximately in a disc shape while a cutting fluid 3 is supplied, wherein the rotary whetstone 1 is furnished at its grinding surface 1a with a slant groove 1b leading to the working surface 1c with an inclination angle θ to the rotational running direction S. With the rotary whetstone 1 the peripheral edge 4a of the plate glass 4 is ground.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a grinding method and a grinding apparatus for grinding a peripheral edge of a sheet glass.

[0002]

2. Description of the Related Art In recent years, flat displays such as a liquid crystal display, an electroluminescence display, and a plasma display have a substantially rectangular shape with a thickness of 0.3 to 4.0 mm.
A thin plate glass of 0 mm is used.

[0003] Such a sheet glass is manufactured and cut out by a well-known industrial molding method, and has a size within a predetermined tolerance range. Processing and chamfering grinding are performed.

As shown in FIG. 4, in a conventional grinding device,
The rotary grindstone 1 is substantially disc-shaped, and a grinding surface 1a provided on the outer periphery thereof is a concave groove having a size substantially the same as the finished size shape of the peripheral edge 4a of the plate glass 4, and is used to grind a diamond or the like with a binder such as a metal bond. The grains are embedded and fixed. Grinding of the peripheral edge 4a of the plate glass 4 is performed by grinding the grinding surface 1 of the rotary grindstone 1 which is rotationally driven while supplying the cutting fluid 3 from the nozzle 2.
This is carried out by bringing the peripheral edge 4a of the plate glass 4 into contact with the abrasive grains exposed from a, and relatively moving the plate glass 4 or the rotary grindstone 1 in that state.

[0005]

However, with the recent enlargement and widespread use of flat displays, it has become necessary to grind the peripheral edge 4a of the sheet glass 4 at a high speed. When the moving speed of the plate glass 4 or the rotary grindstone 1 is increased or the grinding allowance for grinding and removing by one processing is increased, the grinding is performed from the contact portion 4b between the grinding surface 1a of the rotary grindstone 1 and the peripheral edge 4a of the plate glass 4. There is a problem in that the peripheral edge 4a of the sheet glass 4 which has been processed in a clogged state without smooth removal of the glass powder caused by the above-mentioned process is defective due to grinding such as burning or chipping.

Therefore, in order to grind the peripheral edge 4a of many sheet glasses 4 in a short time, the grinding process is divided into multiple stages such as a rough grinding process and a finish grinding process, and a grinding device is added for each process. It is necessary to reduce the grinding allowance for grinding and removing by one processing while maintaining the processing speed, or to increase the number of similar grinding devices in parallel. is there.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems and to provide a sheet glass grinding method and apparatus capable of grinding the periphery of a sheet glass at a high speed.

[0008]

According to the present invention, there is provided a method for grinding a glass sheet according to the present invention, in which a peripheral edge of a glass sheet is brought into contact with a concave grinding surface provided on an outer circumference of a substantially disc-shaped rotary grindstone while supplying a cutting fluid. In the method of grinding a sheet glass to be ground, the peripheral edge of the sheet glass is ground by a rotating grindstone having an oblique groove communicating with the board surface side at an angle of inclination with respect to the rotational traveling direction on the grinding surface. In addition, it is preferable that the peripheral edge of the sheet glass is ground by a rotary grindstone having an inclination angle of the oblique groove of 10 to 70 °.

[0009] In the grinding method of the present invention, in order to increase the moving speed of the plate glass or the rotating grindstone in contact with the grinding wheel and to increase the grinding allowance for grinding and removing by one processing, the oblique surface provided on the grinding surface of the rotating grindstone is required. It is important that the glass powder generated at the contact portion between the peripheral edge of the plate glass and the grinding surface of the rotary grindstone by the groove is immediately discharged to the surface of the rotary grindstone together with the cutting fluid.

[0010] Further, the sheet glass grinding apparatus according to the present invention provides a sheet glass grinding apparatus in which a peripheral edge of the sheet glass is brought into contact with a concave grinding surface provided on an outer periphery of a substantially disc-shaped rotary grindstone while supplying a cutting fluid. In the grinding device, the rotating whetstone is
The grinding surface is provided with an oblique groove having an inclination angle with respect to the rotational traveling direction and communicating with the board surface side, and the inclination angle of the oblique groove is 10 to 70 °. Is preferred.

[0011] As a rotary grindstone used in the grinding apparatus of the present invention, abrasive grains made of CBN, diamond or the like are formed on a grinding surface of a concave groove abutting on the periphery of the sheet glass using a binder such as a resin bond or a metal bond. What is buried and fixed can be used. Further, a plurality of oblique grooves communicating with at least one board surface side are dispersedly arranged in the circumferential direction on the grinding surface. This oblique groove rotates so that glass powder generated at the contact portion between the peripheral edge of the plate glass and the grinding surface of the rotating grindstone during the grinding process can be removed to the board surface side together with the cutting fluid by centrifugal force accompanying the rotation of the rotating grindstone. It is important that an inclination angle is provided with respect to the rotational traveling direction of the grinding surface. If the inclination angle of the oblique groove provided on the grinding surface is less than 10 °, the oblique groove becomes too long, and it becomes difficult to manufacture a rotary grindstone. It becomes difficult to discharge. The inclination angle of the oblique groove is 10
It is preferably about 70 °. Also, as the groove width,
About 0.5 to 3.0 mm is appropriate.

[0012]

According to the grinding method and the grinding apparatus of the present invention, the rotary grindstone has a slanted groove on the grinding surface, which has an inclination angle with respect to the rotational traveling direction and communicates with the board surface side. Since the periphery of the sheet glass is ground by, the glass powder generated by the grinding does not cause clogging on the grinding surface of the rotary grindstone, and the processing speed and the processing amount for grinding the periphery of the sheet glass can be increased, and the processing required for grinding can be performed. Time can be reduced.

[0013]

1 to 3 are explanatory views of a grinding apparatus according to the present invention. In the drawings, reference numeral 1 denotes a substantially disc-shaped rotary grindstone, and 1a denotes a rotary grindstone which comes into contact with a peripheral edge of a sheet glass. 1 is a ground surface, 1b is an oblique groove provided on the ground surface 1a, 1c is a lower surface of the rotary grindstone 1, 2 is a nozzle for supplying a cutting fluid, and 3 is a ground surface.
Is a cutting fluid, 4 is a plate glass, 4a is a peripheral edge of the plate glass 4, 4b is a contact portion between the grinding surface 1a of the rotating grindstone 1 and the peripheral edge 4a of the plate glass 4, and θ is a grinding surface 1a of the oblique groove 1b. Each of the inclination angles with respect to the rotational traveling direction S is shown, and the same parts as those in FIG. 4 are given the same reference numerals.

In the grinding apparatus according to the embodiment of the present invention, FIG.
As shown in the figure, the rotary grindstone 1 has a substantially disk shape with a diameter of 200 mm and a thickness of 10 mm. The cross-sectional shape of the outer peripheral grinding surface 1a has an inclination angle of 50 °, and each of the bottom corners has R0.
It has a concave shape that is almost the same as the finished shape of the peripheral edge 4a of the plate glass 4 that comes in contact with the plate glass 4 at a depth of 25 mm and a depth of 1.0 mm. On the ground surface 1a, diamond abrasive grains of 400/500 grain size have a concentration of 75
Embedded and fixed by metal bond sintered in
60 with respect to the rotational traveling direction S of the grinding surface 1a of the rotary grindstone 1
There are eight oblique grooves 1b having an inclination angle of θ and a width of 1.5 mm and communicating with the lower surface 1c side at intervals of 45 ° in the circumferential direction.

Next, using the grinding apparatus of the present invention,
For example, length 470 mm x width 370 mm x thickness 1.1 mm
The case where the peripheral edge 4a of the sheet glass 4 is ground will be described.

The grinding method of the present invention, as shown in FIG.
The cutting fluid 3 is supplied from the nozzle 2 to the contact portion 4b between the grinding surface 1a of the rotating grindstone 1 rotating at 3,600 rpm and the peripheral edge 4a of the plate glass 4 while being buried with the sintered metal bond of the grinding surface 1a. The peripheral edge 4a of the sheet glass 4 is fixed to 7,000 particles by the fixed diamond abrasive grains having a particle size of 400/500.
While grinding at a linear speed of mm / min, the glass powder generated by the grinding is discharged together with the cutting fluid 3 from the oblique groove 1b to the lower plate surface 1c side of the rotary grindstone 1 immediately by centrifugal force.

As a comparative example, a sheet glass 4 having the same dimensions was ground under the same conditions as those of the embodiment by a conventional grinding apparatus using a rotary grindstone having no oblique groove 1b.

As a result, the dimensional accuracy of the peripheral edge 4a of the sheet glass 4 ground by using the grinding apparatus of the present invention is as follows.
0 ° ± 10 °, the chamfer width is within a predetermined tolerance of 0.7 mm ± 0.2 mm, and 5,000 or more plate glasses 4
Even after grinding, the dimensions and shape were stable, and the appearance was good with no defects such as burning or chipping observed.

On the other hand, many burns and chippings were observed on the peripheral surface of the sheet glass of the comparative example which was ground using a conventional grinding apparatus, and was not usable for flat display use.

[0020]

According to the grinding method and the grinding apparatus of the present invention, the glass powder can be immediately discharged together with the cutting fluid from the contact portion between the grinding surface of the rotary grindstone and the peripheral edge of the sheet glass. By increasing the amount of processing, the periphery of many sheet glasses can be processed to a predetermined external dimension in a short time, which is a practically excellent effect.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a rotary grindstone used in a grinding device of the present invention, wherein (A) is a plan view, (B) is a side view, and (C).
3 is an enlarged view of a main part of FIG.

FIG. 2 is an explanatory diagram of a processing state of the grinding device of the present invention.

3A and 3B are explanatory diagrams of a conventional grinding device, wherein FIG. 3A is an explanatory diagram of a processing state of the grinding device, FIG. 3B is an explanatory diagram of a rotary grindstone used in the conventional grinding device, and FIG. B) is a partially broken side view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotating grindstone 1a Grinding surface 1b Slant groove 1c Lower plate surface 2 Nozzle 3 Cutting fluid 4 Sheet glass 4a Peripheral edge 4b Contact part θ Inclination angle S Rotating running direction

Claims (4)

[Claims] 1. A sheet glass grinding method for grinding a sheet glass by contacting a peripheral edge of the sheet glass with a concave grinding surface provided on an outer periphery of a substantially disc-shaped rotary grindstone while supplying a cutting fluid. A method for grinding a glass sheet, comprising grinding a peripheral edge of the glass sheet with a rotary grindstone having an oblique groove communicating with the board surface side at an inclination angle with respect to a running direction. 2. The method of grinding a glass sheet according to claim 1, wherein a peripheral edge of the glass sheet is ground by a rotary grindstone having an inclination angle of the oblique groove of 10 to 70 °. 3. A plate glass grinding apparatus for grinding a plate glass by contacting a peripheral edge of the plate glass with a concave grinding surface provided on an outer periphery of a substantially disk-shaped rotary grindstone while supplying a cutting fluid, wherein the rotary grindstone includes a grinding wheel. A plate glass grinding apparatus characterized in that the surface is provided with an oblique groove which has an inclination angle with respect to the rotational traveling direction and communicates with the board surface side. 4. The plate glass grinding apparatus according to claim 3, wherein an inclination angle of the oblique groove is 10 to 70 °.