JPH0519305Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a mold for press bending automobile window glass and the like.

(Prior art) As molds for bending automobile window glass, there is a horizontal press type in which sheet glass taken out of the heating furnace in a horizontal state is pressed between upper and lower molds, and a horizontal press type in which sheet glass taken out from the heating furnace in a vertical state is pressed between left and right molds. There is a hanging press type that presses between the molds, and when pressing a plate glass on either type of mold, a surface covering material made of woven cloth such as glass fiber or felt is attached to the pressing surface, and when the mold is released, the glass prevents it from adhering to the mold side.

In addition, the entire surface of the mold for surface pressing is not used as a pressing surface, and cooling air outlets are formed on the molding surface of the mold, as in, for example, JP-A-58-140333.
Some types have a recessed portion for the conveyance roll to move in and out of.

(Problem to be solved by the invention) The above-mentioned surface press mold has a pressed part where the sheet glass comes into contact and a non-pressed part such as a hole or a recess, and the part of the sheet glass that comes into contact with the pressed part is heated to the mold side. The temperature is lower than that of the part corresponding to the non-pressed part. And since this temperature change occurs rapidly at the boundary between the pressed part and the non-pressed part,
Perspective distortion and press distortion will occur at the boundary.

(Means for solving the problems) In order to solve the above problems, the present invention provides a press bending mold having a pressed portion and a non-pressed portion, in which the shape of the surface coating material attached to the surface of the pressed portion at the boundary between the pressed portion and the non-pressed portion changes so that the contact pressure with the plate glass gradually decreases toward the non-pressed portion, or so that the thickness at the boundary gradually decreases toward the non-pressed portion.

(Function) At the boundary between the pressed part and the non-pressed part, the surface of the plate glass and the surface covering material gradually come into contact according to the pressing pressure, so the temperature gradient at the boundary becomes gentle.

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

Fig. 1 is a sectional view of a horizontal press type forming apparatus to which the press bending die according to the present invention is applied, and Fig. 2 is an enlarged view of the main parts of Fig. 1. Then, between the upper and lower molds 1 and 2, the plate glass G heated to near the softening point is fed by the conveyor roll 3 in a horizontal state, and the upper and lower molds 1 and 2 are
The conveyor roll located between is lowered and stored in the recess 4 formed in the lower mold 2, and the plate glass G is transferred onto the lower mold 2. Then, the upper and lower molds 1 and 2 are closed, and the upper and lower molds 1 and 2 are closed. The plate glass G is pressed and bent so that the surface covering material 5 attached to the surface of the press part is brought into contact with the surface of the plate glass G.

The surface covering material 5 is made of glass fiber, asbestos fiber,
Felt made of silica fiber, alumina fiber, carbon fiber, metal fiber, etc. is used. Further, the surface covering material 5 is adhered to the entire press surface while avoiding the recess 4, and the edge portion that becomes the peripheral edge of the recess 4 is processed diagonally to form a roll shape that expands toward the sheet glass G side in cross-sectional view. That's what I do. Specifically, as shown in Fig. 2, the horizontal distance Y of the edge portion is 2 to
7 mm, and the vertical distance Z is preferably 0.5 to 2.5 mm. In order to process the surface coating material 5 as described above, the surface coating material may be hydrated and frozen, and then processed using a drill or the like.

In the above process, a predetermined transport roll 3 is stored in the recess 4 of the lower die 2, and the plate glass G is press-bent formed between the upper and lower dies 1 and 2. The edge portion of the surface covering material 5 is tapered so as to gradually come into contact with the plate glass G according to the press pressure, so that the part corresponding to the recess 4 of the plate glass G (non-pressed part) and the other part ( Even if the temperature differs between the press part and the press part, the temperature change does not occur suddenly and the temperature boundary does not appear clearly, so perspective distortion and press distortion are less likely to occur.

FIG. 3 is a diagram showing an alternative to the embodiment shown in FIG. 1. As shown in FIG. 3, a cushion material 6 is provided on the pressing surface of the mold 2, and the edge portion of the cushion material 6 is tapered However, a surface covering material 5 may be attached to the surface of this cushion material 6. In this case, the surface covering material 5 is not limited to felt, and a thin woven fabric may also be used.

FIG. 4 is a sectional view showing an example in which the mold according to the present invention is applied to a horizontal press type molding device that can perform both pressing and quenching. The upper die 11 and the lower die 12 are hollow, and air introduced into the die is blown out from holes 14 to rapidly cool and strengthen the glass plate G immediately after press bending. A surface covering material 15 is attached to the molding surface of each mold 11, 12, avoiding the holes 14, and the shape of the portion corresponding to the holes 14 is roll-shaped in cross section as shown in FIG. There is. By adopting such a shape, for the same reason as above, the boundary between the temperature of the portion of the glass plate G that contacts the surface covering material 15 (pressed portion) and the temperature of the portion corresponding to the hole 14 (non-pressed portion) is reduced. It does not appear clearly and perspective distortion is unlikely to occur.

6 to 9 show alternatives to the molding device of the type shown in FIG. 4, in which the edge portion of the surface covering material 15 does not have a linearly tapered shape, The cushion material 16 has a rounded shape, and the one shown in FIGS. 7 and 8 has a surface covering material 15 attached to the surface of the cushion material 16.
The edge shape of is approximately funnel-shaped,
The one shown in FIG. 9 has a funnel shape that expands toward the inside of the mold 12, whereas the ones shown in FIGS. 5 to 8 have a funnel shape that expands toward the plate glass G side. . In other words, in the examples shown in FIGS. 5 to 8, the contact pressure between the surface covering material 15 and the sheet glass G is gradually changed at the edge portion to prevent sudden temperature changes, but as shown in FIG. In the embodiment shown in , the thickness of the surface covering material 15 is gradually changed at the edge portion.
The heat taken away by the 5th side is controlled to prevent sudden temperature changes.

Fig. 10 is a front view showing an example in which the mold according to the present invention is applied to a hanging press type molding device, Fig. 11 is a sectional view taken along line A-A in Fig. 10, and Fig. 12 is a
This is an enlarged view of the main part of the figure, and this molding device is a convex mold 21.
and a concave mold 22, the convex mold 21 has a large curved part as a molding surface, and the small curved central part is a concave part 2.
4 is formed, and the plate glass G is press bent between the molding surfaces of a ring mold-like concave mold 22 and a convex mold 21.

Also in this embodiment, the surface covering material 25 is attached to the molding surface, and the molding surface and the recess 2
The shape of the boundary with 4 is processed to be oblique with respect to the plate glass G, as shown in FIG.

Therefore, when pressing and bending the plate glass G with the left and right convex molds 21 and concave molds 22, the concave portions 24 of the convex molds 21
At the peripheral edge of the plate glass G and the surface covering material 2
Since the contact pressure with the glass plate G gradually changes and the heat removed to the surface covering material 25 side also changes gradually, the temperature change of the plate glass G at the boundary of the recess 24 also changes gradually.

(Effects of the invention) As explained above, according to the invention, the contact pressure between the glass plate and the surface contact material is gradually changed at the boundary between the pressed part and the non-pressed part of the press bending die of the glass plate, or Since the thickness of the surface contact material is gradually changed, the heat removed from the sheet glass to the surface contact material side also changes gradually, and therefore the temperature change of the sheet glass at the boundary between the pressed part and the non-pressed part is reduced. It becomes gentle, and perspective distortion and press distortion are improved.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a forming apparatus to which the press bending die according to the present invention is applied, Fig. 2 is an enlarged view of the main part of Fig. 1, Fig. 3 is a view similar to Fig. 2 showing an alternative plan, 4
The figures are a sectional view similar to Fig. 1 showing another embodiment, and Fig. 5.
The figure is an enlarged view of the main part of FIG. 4, FIGS. 6 to 9 are views similar to FIG. 5 showing an alternative, FIG. FIG. 10 is a sectional view taken along the line A-A, and FIG. 12 is an enlarged view of the main part of FIG. 11. In addition, in the drawing, 1, 2, 11, 12, 21, 22
is a mold, 5, 15, 25 are surface covering materials, 6, 1
6 is a cushion material, and G is a plate glass.

Claims (1)

[Scope of utility model registration request] A press bending mold having a press part for bending sheet glass and a non-press part for storing rolls or blowing out air, and having a surface contacting material that comes into contact with the glass attached to the surface of the press part. Either the shape of the contact material at the boundary between the pressed part and the non-pressed part is sloped so that the contact pressure with the sheet glass gradually decreases toward the non-pressed part, or the thickness at the boundary part is increased toward the non-pressed part. A press bending mold for sheet glass, which is characterized by its gradual thinning.