JPH062596B2 - How to cut tempered glass - Google Patents

Description

TECHNICAL FIELD The present invention relates to a so-called tempered glass cutting method in which a high temperature plate glass is rapidly cooled to generate residual stress in the thickness direction to form a compressive stress layer on the surface.

[Conventional technology]

Regarding the method of cutting tempered glass, the heating temperature of the cutting part should be lower than other parts to cool it during tempering, or the cooling temperature gradient should be loosened to reduce the tensile stress distributed in the central layer. Method of cutting (Japanese Patent Publication No. 47-44009)
No.), a narrow zone is provided at the position of the cutting line, and in this zone, the glass is cut in a structural state having a smaller specific volume than the adjacent glass during the strengthening process (Japanese Patent Publication No.
No. 47-1311) etc. [Problems to be solved by the invention] However, the conventional cutting method is to cut by performing some heat treatment and not to cut the glass after the strengthening treatment.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method capable of cutting tempered glass after treatment, which has heretofore been impossible, without heat treatment or the like.

[Means for solving problems]

Preferably, the tempered glass plate is kept substantially vertical to the blade of the band saw, which runs at a peripheral speed of 1,100 m / min to 1,300 m / min in one direction, and is cut while pressing at a speed of 10 mm / min or less.

[Action]

The tempered glass has a compressive stress layer on the surface as shown in FIG.
A tensile stress layer that balances the compressive stress of the surface is formed inside, and when a scratch reaches the internal stress layer, a crack develops and propagates rapidly from that point, so it is not possible to cut tempered glass at room temperature. Although it was totally impossible, use a band saw with less vibration, and firmly clamp the tempered glass that is the work piece so that stress is not concentrated on the table that moves in the front-back direction. The tempered glass is pressed by the blade by sending it at a speed of 0.5 mm / min to 5 m / min, which causes the maximum tensile stress in the center of the thickness direction to not self-propel even if cracks occur, for example 350 kg / cm ² or less. It is highly probable that

Further, as shown in the embodiment (Fig. 3), it is optimal to feed the tempered glass to the traveling blade with a slight inclination, not parallel, but this is because the tempered glass has a pressing force other than the pressing force from the blade. This is probably because the blade is receiving lateral force as it travels.

〔Example〕

 Hereinafter, the present invention will be described with reference to the drawings.

FIG. 1 is a schematic view of an essential part showing a band saw, FIG. 2, and FIG.
The figure shows the relationship between the blade and the tempered glass at the time of cutting.
It is an arrow view (elevation view) and a plan view.

The band saw 1 is a stainless steel band having a width of 25 mm and a thickness of 0.2 mm, which is formed by electrodepositing diamond grains to form a blade 2 and is driven in one direction by a variable speed electric motor 3 or the like. The workpiece is clamped and sent to a table (not shown).

Tempered glass with high degree of strengthening as sample I, sample II
As a tempered glass with a low degree of tempering, 100 mm × 200 mm × 4.0 mm
Are prepared respectively, the tempered glass is kept almost vertical to the blade as shown in FIG. 2, and as shown in FIG.
T = 0, not t = 0 (parallel) to the running blades.
Feed rate is 1-2 mm while slightly tilting such as 5 mm
Table 1 shows the results of cutting by changing the peripheral speed of the blade as / min. (○ means that it could be cut well, and × means that it was defective.) As is clear from this result, the blade peripheral speed is 1,200 m /
The tempered glass could be cut within the range of 1,100 m / min to 1,300 m / min centering on the minute.

The present invention is not limited to the embodiment and various applications are possible.

The processing machine is not limited to the band saw, and it is possible to use a disk having a relatively large radius.

Although the present invention has been described with the method of feeding the tempered glass to the blade that runs at a fixed place, it goes without saying that the method of fixing the tempered glass and moving the housing part in which the blade is incorporated may be used.

〔The invention's effect〕

The present invention is a conventional tempered glass cutting before the tempering process,
This overturns the premise that it must be carried out during heat treatment, and has the remarkable effect of making it possible to cut even tempered tempered glass at room temperature.

[Brief description of drawings]

FIG. 1 is a schematic view of an essential part showing a band saw, FIG. 2, and FIG.
The figure shows the relationship between the blade and the tempered glass at the time of cutting.
An arrow view (elevation view) and a plan view, and FIG. 4 are sectional stress distribution diagrams of the tempered glass. 1 ... Band saw, 2 ... Blate, 4 ... Tempered glass

Claims (1)

[Claims] 1. A tempered glass plate is held almost vertically on a blade that travels in one direction at a peripheral speed of 1,100 m / min to 1,300 m / min.
A method for cutting tempered glass, which comprises cutting while pressing at a speed of mm / min or less.