JPH0622791B2 - Continuous polishing equipment for glass plates - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a continuous polishing apparatus for glass plates.

[Prior Art] Conventionally, polishing of a relatively thin glass plate such as a glass substrate for liquid crystal has been performed by an Oscar type single-side polishing machine or a double-side polishing machine. With these methods, a polishing surface plate added to the glass plate is used. Since the difference in the peripheral speed is used, the glass removal is different at each point of the glass plate, and the larger the glass plate size is, the more polishing allowance must be taken. on the other hand,
Since the glass plate is supported within the frame of the carrier, there is a limit to the size increase in view of the polishing load. Further, since it is difficult to automate these due to the apparatus configuration, a great deal of manpower is required, and as a result, there is a problem that the probability of handling scratches occurring when the glass plate is attached to or detached from the polishing apparatus increases.

[Problems to be Solved by the Invention] An object of the present invention is to provide a novel polishing apparatus that overcomes the above-mentioned drawbacks of the prior art.

[Means for Solving the Problems] The present invention has been made to solve the above-described problems, and includes a polishing table for transferring a glass plate in one direction,
A plurality of polishing tools arranged above the polishing table along the transfer direction of the glass plate, each polishing tool performing an eccentric rotational motion with respect to the glass plate by an eccentric shaft, and adjacent polishing tools. The present invention provides a continuous polishing apparatus for glass plates, which is installed so that the rotational phase of the glass plate is reversed.

Next, the polishing apparatus according to the present invention will be specifically described with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a cantilever beam for supporting a polishing mechanism, which is usually made of cast metal. These cantilever beams are arranged on the polishing line according to the number of polishing tools 3. The polishing line is composed of a polishing table 7 connected on a rail 6 and traveling in the direction of the arrow.
Is attached and fixed on this polishing table through a thin cushion material so as not to be scratched.

Although not shown in the figure on the back side of the polishing table 7, a rack is provided vertically to the table so that it can be operated via a drive motor and a pinion provided below the table. The rack is provided perpendicularly to the table in order to prevent the table from vibrating vertically to the polishing tool due to backlash with the pinion. Further, this table driving motor is equipped with an inverter so that the speed can be varied between 0 and 100 cm / min. At the position where the glass plate 5 is polished, the table is fed by the rails 6 in this way, but the return line after polishing does not cause much problems in positional accuracy, vibration, etc., so that the table is returned by the roll 8.

The polishing tool 3 is usually A1 or A to reduce the weight.
Although it is made of one alloy, a foamed polyurethane pad, for example, is attached as a polishing pad on the lower surface, though not shown. Here, the shape of the polishing tool is preferably a strip shape from the viewpoint of uniformly polishing the glass surface. In this polishing tool 3, a disk 11 is mounted on the lower end of a rotary shaft that is supported by a ball bearing 10 on the cantilever 1 described above, and a support plate 13 is mounted on the disk 11 by an eccentric shaft 12 that is eccentrically provided. It is attached to a surface plate 14 mounted on a plate via a cylinder 5. In this case, the polishing tool 3
Is usually attached to the surface plate 14 by a universal joint 16. This is to flexibly cope with the step difference of the tapered glass plate or the joint between the glass plates. The surface plate 14 is stably attached to the support plate 13 by the guides 15 at both ends, and is devised so as not to tilt left and right with respect to the stroke of the cylinder 5.

Although not shown in the figure, the disk 11 has an eccentric shaft.
To eliminate the rotational moment due to 12, it is preferable to balance on the opposite side of the eccentric shaft 12. This can minimize vibration.

Up to this point, the mounting structure for one polishing tool has been described.
A polishing tool 3 is similarly attached to each cantilever 1. The polishing tools 3 are drivingly connected to the drive shaft 9 so that they can rotate at the same time. In this case, the drive shaft 9 is connected via a motor inverter, so that the rotation speed of the polishing tool is 0 to 30.
Can be changed between 0 rpm.

Further, it is important in the present invention that the polishing tools 3 arranged in parallel along the polishing line have the same rotation directions, but as will be described later, rotation of the mass center of gravity of the adjacent platen 14 and polishing tool 3 is adjacent to each other. The phase is inverted by 180 ° as shown in FIG. With such a configuration, when a plurality of polishing tools are placed on the glass plate, the load applied to the glass plate can be balanced, and particularly when an even number of polishing tools are operating on the glass plate 5. , Can offset the load.

[Operation] Next, the operation of the polishing tool will be described with reference to FIGS. 2 and 3.

In the device of the present invention, the table 7 continuously moves in the direction of the thick arrow. The polishing tool 3 moves as shown in FIG. 2 by the eccentric shaft. Details of the exercise are shown in FIGS. 3 (a) and 3 (b). 18 is the mass center of gravity of the polishing tool, and 17 is the locus of movement of the mass center of gravity by the eccentric axis. In (a), the polishing tools adjacent to each other have the same rotation direction, but the rotation phase of the mass center of gravity is reversed by 180 °. Reference numeral 19 indicates the direction of the force applied to the glass plate 5 by the polishing tool.

In the present invention, by providing such a mechanism, when a plurality of polishing tools act on the glass plate, they act to cancel each other, and particularly when the number is even, the load applied to the glass plate 5 is completely canceled. Even when an odd number of polishing tools are mounted, the load applied to the glass plate is incomparably smaller than that of the conventional Oscar type single-side polishing machine or double-side polishing machine. Therefore, it becomes possible to continuously grind a large-sized glass plate without supporting the glass plate in the carrier as in the conventional case.

[Embodiment] In FIG. 1, the size of each table is 500 mm × 125.
The feed rate was 0 to 100 cm / min, which was variable by the inverting. The size of each polishing tool was 480 mm × 100 mm, the pitch between the polishing tools was 100 mm, and a total of 32 pieces were arranged. The number of rotations was 0 to 300 rpm, which was variable by an inverter.

The glass plate is 300 mm × 300 mm × 1.1 mm, and it is fixed to the table by a method in which a polishing cloth is adsorbed with water. A foamed polyurethane pad impregnated with cerium oxide was used as a pad, and a cerium oxide solution of about 10 to 15 be was used as a polishing liquid by sieving with a # 200 or # 400 mesh.

Below, an example of the time required for removing minute undulations (~ 0.2 μm height) and scratches on the surface of the glass plate based on the above-mentioned embodiment is compared with the case where the conventional polishing method is used. I will list it.

[Advantages of the Invention] In the conventional Oscar type single-side polishing machine, a polishing allowance of 5 μm or more had to be taken in order to remove the irregularities on the glass surface. Since the phases are shifted by 180 °, the load applied to the glass plate is balanced and no difference in peripheral speed is generated in the polishing tool. As a result, the polishing allowance is about 2 to 3 μm and a good surface is obtained. Furthermore, since the polishing tools are lined up in a row, rough polishing can be performed in the first stage, interruption can be easily performed as with ordinary glass for liquid crystal, and in the second stage it can be easily obtained by exchanging the pad with a precision polishing surface similar to a photomask. Has been confirmed.

Further, in the preferred embodiment of the present invention, since the polishing tool is supported by the cantilever by the two shafts, the polishing tool can always be held stably, which allows the polishing tool to be enlarged and the glass to be used. The plate can be evenly polished.

Furthermore, when the polishing tool is attached to the support plate via the surface plate,
Not only is the support of the polishing tool more stable, but it is also possible to flexibly deal with irregularities and steps on the polishing surface.

[Brief description of drawings]

Figure 1 is. FIG. 2 is a schematic perspective view showing an embodiment of the device of the present invention, FIG. 2 is a plan view showing the basic structure of the polishing tool, and FIG. 3 is an explanatory view showing the movement of the polishing tool in FIG. is there. In the figure, 1 is a cantilever beam, 3 is a polishing tool, 5 is a glass plate, and 7 is a polishing table.

Claims (1)

[Claims] 1. A polishing table for transporting a glass plate in one direction, and a plurality of polishing tools arranged above the polishing table along the transport direction of the glass plate, each polishing tool comprising: An apparatus for continuously polishing a glass plate, which is installed such that an eccentric shaft makes an eccentric rotary motion with respect to the glass plate and the rotation phases of adjacent polishing tools are reversed.