JPH0441152Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an apparatus for manufacturing tempered glass used as window glass for buildings or automobiles.

(Prior Art) To manufacture tempered glass, a plate glass is first heated to a predetermined temperature, and the heated surface of the plate glass is rapidly cooled to generate compressive stress on the surface of the plate glass.

As devices for this purpose, those disclosed in Japanese Patent Publication No. 42-22793 or Japanese Patent Publication No. 61-29891 are known.

As shown in FIG. 5, the above-mentioned apparatus has a schematic configuration in which a heating furnace 100 and a quenching device 101 are installed in series, and inside the heating furnace 100 there is an air table 102 that blows out hot air to convey and heat the plate glass G. A quenching nozzle 103 is installed on the ceiling of the quenching device 101 to eject cooling air onto the top surface of the plate glass G.
At the bottom of the quenching device 101, an air table 104 is provided that cools the lower surface of the glass plate G while transporting it.

(Problems to be Solved by the Invention) In the conventional apparatus described above, when the plate glass G is carried into the quenching device 101 from the heating furnace 100, that is, when the state shown in FIG. Rapid cooling nozzle 103a provided at the inlet
The cooling air flows into the rear end side along the upper surface of the glass plate G as shown by arrow C. Also, the rapid cooling device 10
The cooling air from the air table 104a provided at the inlet of
2, and the hot air from the air table 102 flows in this gap toward the outlet, so the cooling air from the air table 104a does not flow toward the rear end along the lower surface of the plate glass G. .

Therefore, only the rear upper surface of the glass plate G is intensively cooled, and as a result, when the glass plate G is a flat glass, the front end a is flat but the rear end b is curved upward, as shown in FIG. 6A. If the glass plate G is a curved glass, the curve at the rear end b is deeper than at the front end a, as shown in FIG. 6B.

(Means for solving the problem) In order to solve the above problem, the present invention disposes a heating device such as a gas burner between the outlet of the heating furnace and the inlet of the quenching device. Therefore, the upper surface, especially the rear upper surface, of the plate glass transported from the heating furnace to the quenching device is heated.

(Function) When the plate glass is carried into the quenching device from the heating furnace, the rear upper surface of the plate glass is heated by the heating device, and is heated by the cooling air flowing from the cooling nozzle of the quenching device to a greater extent than the other upper surfaces. It is never cooled down.

(Example) An example of the present invention will be described below based on the accompanying drawings.

FIG. 1 is a cross-sectional view of the tempered glass manufacturing apparatus according to the present invention, and FIG. 2 is a side view of the heating device. An air table 3 is provided to convey G in a floating state toward the exit portion 1a.
This air table 3 has a large number of nozzle holes 4, and hot air is ejected from the nozzle holes 4 to the lower surface of the glass plate G, thereby floating the glass plate G and heating the glass plate G as described above. Furthermore, a heating gas burner and the like are arranged on the ceiling of the heating furnace 1 .

On the other hand, the ceiling of the rapid cooling device 2 is provided with a large number of cooling air jet nozzles 5, and the bottom thereof is provided with an air table 6 that jets cooling air.

Further, above between the outlet 1a of the heating furnace 1 and the inlet 2a of the quenching device 2, a gas burner 7 as a heating device and a sensor 8 for detecting the tip of the glass plate G being conveyed are arranged. ing.

The gas burner 7 is used when the plate glass G is curved glass, and its specific structure is as shown in FIG. ... are arranged, gas is supplied to each nozzle 10 through piping 11, and a pilot lamp for ignition is provided near the tip of each nozzle 10. A flow rate adjustment valve 12 is provided in the middle of the pipe 11, and a bypass pipe 13 is provided in a part of the pipe 11, and the sensor 8 is connected to the bypass pipe 13.
A solenoid valve 15 and a flow rate adjustment valve 16 are provided, which are opened via a timer 14 in response to a signal from the pump.

Here, the flow rate adjustment valve 12 is for a pilot lamp, and through this valve 12,
Gas is constantly supplied to the pilot lamp at a gas pressure of about 40 mmAq, and the flow rate adjustment valve 16 is for the gas jet nozzle 10, and after the sensor 8 detects the tip of the plate glass G, the timer 14
After a predetermined period of time has elapsed, for example, after the tip of the glass plate G has been detected and the glass plate G has been conveyed by 100 mm, the solenoid valve 15 is turned on and gas is supplied to the nozzle 10.

Next, specific experimental results are shown in FIGS. 3 and 4.

The plate glass used in this experiment was 500 mm wide and 500 mm long.
The curved glass was 1000mm and 3.5mm thick. Also,
In the graph in Figure 3, the horizontal axis is burner back pressure (mmAq),
The vertical axis is the gap (mm) with the inspection mold, and a positive value of the gap indicates that the curve is deeper than the standard value (reference value), and a negative value indicates that the curve is shallower than the standard value. Further, in the graph of FIG. 4, the horizontal axis represents the back pressure of the burner, and the vertical axis represents the difference in bending (difference in gap) between the front end a and the rear end b of the glass plate.

The experimental results shown in FIG. 3 are the results when the gas burner is constantly lit and the entire top surface of the glass plate G is heated, and the experimental results shown in FIG. 4 are the results when the sensor 8 detects the tip of the glass sheet G. later,
This is the result of igniting the gas burner 7 when the plate glass G has been conveyed 100 mm.

As is clear from these figures 3 and 4,
When the gas burner 7 is constantly lit to heat the entire top surface of the glass plate G, the curve at the rear end b of the glass plate G tends to be deeper than the front end a, regardless of the back pressure of the gas burner, but only at the rear of the glass plate G. It can be seen that by heating the front end part a and the rear end part b, the bending becomes equal at a predetermined back pressure (approximately 750 mmAq). In addition, the back pressure of the gas burner at which the bending of the front end a and the rear end b is equal was approximately 750 mmAq in the experimental example, but this is thought to vary depending on the thickness of the plate glass, etc. . However, even if the thickness of the glass plate changes, by appropriately selecting the back pressure of the gas burner, a tempered glass whose front end a and rear end b are equally curved can be obtained.

In the embodiment, an air table is used as the conveyance means, but the present invention can also be applied to an apparatus using rolls.

(Effect of the invention) As explained above, according to the invention, not only can a tempered glass with equal curvature at the front end and rear end be obtained, but also by adjusting the back pressure of the gas burner, it is possible to actively The bending depth can be adjusted.

That is, in the case of conventional bending tempered glass manufacturing equipment, a ceramic bed having a curvature equal to that of the intended bending tempered glass is prepared, a hot air jet nozzle is formed in this ceramic bed, and while the plate glass is conveyed, Because the glass is bent and formed, the entire ceramic bed had to be replaced when manufacturing bent tempered glass with a different curvature. However, if the curvature is slightly changed, the gas burner can be replaced without having to replace the ceramic bed. It is sufficient to control the back pressure.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of the tempered glass manufacturing apparatus according to the present invention, Figure 2 is a side view of the gas burner, Figure 3 is a graph showing the relationship between the back pressure of the gas burner and the bending depth, and Figure 4 is the back view of the gas burner. A graph showing the relationship between pressure and the bending difference between the front and rear ends of a plate glass. Figure 5 is a cross-sectional view of a conventional tempered glass manufacturing apparatus. Figures 6 A and B are perspective views of tempered glass manufactured by the conventional apparatus. be. In addition, in the drawing, 1 is a heating furnace, 2 is a rapid cooling device, 3, 6
5 is an air table, 5 is a cooling nozzle, 7 is a gas burner as a heating device, and G is a plate glass.

Claims (1)

[Scope of utility model registration request] Manufacture of tempered glass in which a heating furnace and a quenching device through which the plate glass passes are arranged in succession, the plate glass is heated while passing through the heating furnace, and the heated plate glass is carried into the quenching device where it is rapidly cooled and strengthened. An apparatus for manufacturing tempered glass, characterized in that a heating device for heating the rear upper surface of the plate glass is disposed between the outlet of the heating furnace and the inlet of the quenching device.