JP2687533B2 - Method for manufacturing window glass with gasket - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for manufacturing a window glass with a gasket, which is suitable for window glass for automobiles and window glass for construction.

"Prior Art" Installing a gasket or molding made of rubber or synthetic resin (hereinafter collectively referred to as "gasket") on the periphery of window glass for vehicles such as automobiles or window glass for construction for decoration or sealing. Is usually done.

Conventionally, this gasket is attached to a window glass by a method in which a gasket formed in advance by extrusion or the like is adhered to or fitted into the periphery of the window glass. However, this method is not economical because it has a large number of steps and a large number of manpower.

Therefore, in order to solve this problem, in recent years, a method of manufacturing a window glass with a gasket has been proposed in which the gasket is integrally formed on the peripheral portion of the window glass. An example of this manufacturing method will be described with reference to FIG.
The mold 11 is arranged in the mold 11 so as to be sandwiched between the upper mold 12 and the lower mold 13. As a result, a cavity space 14 forming a gasket is formed between the inner surfaces of the upper mold 12 and the lower mold 13 and the peripheral portion of the window glass G. In addition, in order to prevent the surface of the window glass G from being damaged, elastic bodies 15 and 16 are attached to the portions of the upper mold 12 and the lower mold 13 that come into contact with the window glass G. In this state, a gasket material such as a melted material of rubber or elastomer or a raw material mixture capable of forming sesame or elastomer is injected into the cavity space 14 and the gasket material is solidified, so that the gasket is attached to the peripheral portion of the window glass G. Mold integrally. Then, the upper mold 12 and the lower mold 13 are opened and the window glass G and the molded gasket are taken out from the molding die 11. In addition, as an example of such a manufacturing method,
For example, JP-A-57-158481, JP-A-58-73681, JP-A-60-4015, JP-A-60-63115, and JP-A-61-79613.
And the like.

However, in the method of manufacturing a window glass with a gasket as described above, when the curvature accuracy of the window glass is insufficient,
Since the elastic bodies arranged on the entire circumference have the same shape and elastic modulus, the elastic body may be damaged at a portion where the curvature accuracy is insufficient. That is, in the portion where the accuracy of curvature of the window glass is insufficient, when the molding die is tightened, the above-mentioned portion of the window glass is deformed beyond the limit displacement of the glass, and stress concentrates, leading to damage. Such damage due to insufficient curvature accuracy particularly occurs when the window glass G is bent into a complicated shape or deep-bent (having a small radius of curvature or a large bending angle). easy.

On the other hand, if the elastic modulus of the elastic body is made uniform all around to prevent such damage, the sealing surface pressure at the part where the elastic body and the window glass come into contact is insufficient and resin leakage and burrs occur during molding. There was a problem that was generated.

"Problems to be solved by the invention" The present invention has been made in view of the problems of the above-mentioned conventional techniques, and its object is to have a high sealing property in spite of insufficient curvature accuracy of the window glass, and It is an object of the present invention to provide a method for manufacturing a window glass with a gasket, in which stress is less concentrated on the window glass, damage is prevented, and the appearance is good.

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention has a window glass arranged in a molding die, and a gasket molding cavity formed between the peripheral edge of the window glass and the inner surface of the molding die. In a method of manufacturing a window glass with a gasket by injection-molding a gasket material in a tee space, an elastic body having an elastic modulus changed according to the curvature accuracy of each portion of the window glass is arranged in a portion of the molding die that contacts the window glass. The contact surface with the window glass is sealed via this elastic body.

In the present invention, the elastic body is integrated as a whole, and the elastic modulus may be changed according to the curvature accuracy of each portion of the window glass due to the difference in shape and material of each portion.
Further, a plurality of elastic bodies having different elastic moduli may be arranged in combination along the portion of the mold that contacts the window glass.

Further, the elastic body preferably has a Young's modulus of 1 to 5,000 kg / cm ² . If the Young's modulus is less than 1 kg / cm ² , the problem of large burr formation during molding occurs,
If it exceeds 0 kg / cm ² , there is a problem that the glass breaks during mold clamping.

Furthermore, as the material of the elastic body, natural rubber, synthetic rubber, synthetic resin elastomer or the like is preferably adopted.

[Operation] As described above, in the present invention, the portion of the window glass where the curvature accuracy is insufficient is pressed by the elastic body having the largest possible elastic modulus within the range where the limit displacement amount of the window glass is not exceeded during mold clamping. This can prevent the window glass from being damaged. Further, by using the elastic body as described above, it is possible to exert the maximum effect on the sealing property of the contact portion between the window glass and the elastic body as long as the glass is not damaged.

[Examples] Hereinafter, a method for manufacturing a window glass with a gasket according to the present invention will be described with reference to the drawings. The same reference numerals are given to common members in FIGS. 1 to 4.

FIG. 1 shows an example of a molding die used in the manufacturing method of the present invention. In this mold 11, upper mold 12 and lower mold
Elastic body 4 (1, 2, 3) at the contact portion between 13 and the window glass G
And 5 (6, 7, 8) are arranged respectively. The elastic bodies 4 and 5 serve to press the window glass G against the mold. In this case, the elastic body, of course, has as large an elastic modulus as possible within the range where the window glass G is not damaged. Then, when the mold clamping is completed, the window glass G is prevented from being damaged without concentrating excessive stress, and good sealing property is imparted.

FIG. 2 shows an example of the arrangement of the elastic bodies according to the curvature accuracy of the window glass G. Usually, in the case of being bent into a complicated shape or deep-bent, the accuracy of curvature is often insufficient especially in a portion having a small radius of curvature or a large bending angle, and therefore the accuracy of curvature is relatively high. It is preferable to increase the elastic modulus in the high portion and weaken the elastic modulus in the low curvature accuracy portion. The figure shows an arrangement example of the elastic bodies 1, 2, 3, and 4 in the upper mold 12. Both sides of the glass G are bent along the broken line portion. Since the curvature accuracy is relatively high at the center of the upper and lower sides of the glass G, the elastic bodies 1 and 3 having a strong elastic modulus are arranged. Further, at the shoulders on both sides of the upper side of the glass G, the elastic bodies 2, 2 having a weak elastic modulus are arranged because the bending angle is slightly large and the curvature accuracy is insufficient. Further, at the shoulders on both sides of the lower side of the glass G, since the bending angle is the largest and the curvature accuracy is the least, the elastic bodies 4 and 4 having the weakest elastic modulus are arranged.

Although not shown in the drawings, the lower mold 13 also has elastic bodies 5, 6, 7, 8 having different elastic moduli in the same manner as described above.
Are arranged respectively. However, in the present invention, only the elastic bodies arranged in one of the upper and lower molds 12 and 13 may be partially different in elastic modulus.

Further, in the above example, the elastic body 1 having different elastic moduli
~ 4 or 5-8 are arranged in combination,
The elastic bodies arranged in the upper and lower molds 12 and 13 are integrated as a whole, and the elastic modulus may be partially changed by changing the shape and the material.

As the elastic bodies 1 to 8, elastic materials such as natural rubber, synthetic rubber and synthetic resin elastomer are adopted. SB for example
Synthetic rubbers such as R, NBR, EPM, and IIR, silicone rubber (elastomer), polyurethane elastomer, and other synthetic resin elastomers are preferably adopted.

In the present invention, the cross-sectional shape of the elastic bodies 1 to 8 is not limited, and may be, for example, a rectangular shape, a hollow body, a deformed shape, a circular shape, an annular shape, or any other shape. The elastic bodies 1 to 8 can have various elastic moduli by changing their shapes and materials.

3 (a) to 3 (m) show examples of preferable cross-sectional shapes of the elastic bodies 1-8. (A) has a rectangular cross section, (b) has a rectangular cross section and has two hollow portions 20 formed therein to adjust the elastic modulus, and (c) has an H-shaped cross section and an intermediate thin portion 21. The elastic modulus is adjusted with, (d) is a left protrusion 22 which is a glass contact surface, and is tapered (e) is a left protrusion 22 which is a glass contact surface.
Having a tapered shape and a hollow portion 23 formed therein, (f) shows two elastic members having different elastic moduli.
Harder elastic member made of 24 and 25 joined together
24 is in contact with the glass, (g) is one in which two elastic members 24 having different elastic moduli are embedded inside the elastic member 25 along the longitudinal direction, (h) is different in elastic modulus 2 The two elastic members 24 and 25 are joined to each other, and the thin portion 26 is provided in the middle portion to form an H-shaped cross section as a whole.
The one in which the harder elastic member 24 contacts the glass, (i) has substantially the same structure as (h) above, but has the groove 27 on the glass contact surface, and (j) has a different elastic modulus. Two
The two elastic members 24, 25 are joined together, and the harder elastic member 24 serves as a glass contact surface, and that portion is formed in a tapered shape, and the groove 27 is provided in the glass contact surface, (k ) Is one in which the groove 27 is not provided in the above (j), and (l) has a structure similar to that of the above (i), and is a side wall located near the glass contact surface as shown in the enlarged view (m). A small ridge 28 having a radius of 0.2 to 1.0 mm, preferably 0.5 mm is formed in the portion, and the ridge 28 has an effect of preventing the gasket material from entering the glass contact surface.

4A to 4C, upper and lower molds of the elastic bodies 1 to 8 are shown.
The attachment mode to 12, 13 is shown. (A) is one in which an elastic body and a mold are bonded together, (b) is one in which the ridges 29 are spread in a V-shaped cross section provided in the elastic body and are fitted into the dovetail groove 30 provided in the mold, ( c) shows a pin 32 provided in a mold inserted into a hole 31 provided in the elastic body. Of course,
In the present invention, the elastic body can be attached to the mold by other various fixing means.

Furthermore, the gasket is made of synthetic resin or rubber,
In particular, it is preferable to use an elastomer or a soft synthetic resin. The gasket material injected into the mold comprises a melt of the synthetic resin or a liquid synthetic resin raw material mixture which reacts in the mold to become a synthetic resin. As the former, for example, melted soft vinyl chloride resin, thermoplastic polyester elastomer, styrene-diene thermoplastic elastomer,
Examples include, but are not limited to, ethylene-unsaturated carboxylic acid copolymers. Examples of the synthetic resin obtained from the latter raw material mixture include, but are not limited to, polyurethane-based elastomers, polyurethane-urea-based elastomers, polyurea-based elastomers, polyamide-based resins, epoxy resins, and unsaturated polyester-based resins. .

Furthermore, as the injection molding using the molding die 11 in the present invention, reaction injection molding (RIM) is particularly preferable. This method is one of the methods of injecting the above-mentioned raw material mixture to perform molding, and at the time of injection, the raw material components are rapidly mixed and injected into a molding die, and at the same time, the raw material mixture is rapidly reacted in the molding die for synthesis. It is a method of obtaining a resin molded product. This method is very suitable as a method of molding a gasket around the window glass in the mold because the fluidity inside the molding cavity is better and the pressure inside the molding cavity is lower than injection molding of molten synthetic resin. It is.

As the material of the gasket molded by reaction injection molding, the above-mentioned polyurethane elastomer, polyurethane urea elastomer, and polyurea elastomer are particularly preferable. These are obtained using a compound having two or more active hydrogen-containing functional groups selected from a hydroxyl group, a primary amino group or a secondary amino group and a compound having two or more isocyanate groups as reactive raw materials. The above-mentioned two kinds of reactive raw materials are mixed and injected at the time of injection, and the above-mentioned elastomer is formed by reacting these two kinds of compounds in a mold. The compound having two or more active hydrogen-containing functional groups has a molecular weight per functional group
800 or more, especially 1000 to 4000, 2 to 8 functional groups per molecule, especially 2 to 4 high molecular weight active hydrogen compounds and chain extenders (ie 2 to 4 functional groups per molecule) 8,
Particularly, a combination of low molecular weights of 2 to 3 and especially compounds of 400 or less) is preferable. Specifically, for example, polyether polyols, polyether polyamines, hydroxyl group-containing hydrocarbon polymers such as polyester polyols, other high molecular weight active hydrogen compounds that are liquid at room temperature or under heating at the time of injection (about 60 ° C or less), And ethylene glycol,
There are chain extenders such as 1,4-butanediol, diethyltoluenediamine and monochlorodiaminobenzene. Each of these high molecular weight active hydrogen compounds and chain extenders can be used in combination of two or more.

Particularly preferred high molecular weight active hydrogen compounds are polyether active hydrogen compounds such as polyether polyols and polyether polyamines, and diols and diamines as chain extenders. Examples of the compound having two or more isocyanate groups include diphenylmethane diisocyanate,
Polymethylene polyphenyl isocyanate, tolylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, and other polyisocyanates and modified products thereof (for example, carbodiimidated modified products, prepolymer modified products, nurate modified products, etc.) are preferable. The reactive raw material can be used together with other auxiliary raw materials. Examples of the auxiliary materials include catalysts, fillers, reinforcing agents, stabilizers (UV absorbers, light stabilizers, antioxidants, etc.), colorants, and foaming agents.

Test Example As shown in FIG. 5, the window glass G was placed on the lower mold 13. Due to the lack of curvature accuracy of the window glass G, the gap a between the end of the window glass G and the lower mold 13 was 1.2 mm. Also,
The length (span) b of the window glass G lifted from the lower mold 13 was 78 mm. As the window glass G, a laminated glass having a thickness of 4.3 mm was used.

The limit displacement of the edge portion of the window glass G in such a state is 0.68 mm when calculated with σ = 400 kg / cm ² . Further, the stress generated at this time is 400 kg / cm ² .

Next, through the elastic body with a Young's modulus of 32 kg / cm ² , the window glass G
Tighten, and the displacement of the edge of the window glass G at that time,
The presence or absence of cracks in the window glass G and the generated stress were examined.

Further, the window glass G was directly clamped with a mold without providing an elastic body, and the displacement of the edge portion of the window glass G at that time, the presence or absence of cracks in the window glass G, and the generated stress were examined. The results are shown in the following table.

As described above, it is understood that glass breakage can be prevented by using an elastic body having an appropriate elastic modulus so that the displacement of the window glass G during tightening does not exceed the limit displacement.

[Advantages of the Invention] As described above, according to the present invention, since the window glass is pressed by the elastic body whose elastic modulus is changed according to the curvature accuracy of each part of the window glass, excessive stress does not occur and the window is not generated. It is possible to prevent breakage of the glass. In addition, the elastic body can be selected to have the largest elastic modulus as long as it does not cause damage to the window glass, so that good sealing property can be obtained.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view showing an example of a molding die for carrying out the method of the present invention, FIG. 2 is a view showing an example of a layout of elastic bodies, and FIGS. 3 (a), (b), ( c), (d), (e),
(F), (g), (h), (i), (j), (k),
(L) is a sectional view showing different examples of the shape of the elastic body adopted in the present invention, FIG. 3 (m) is a partially enlarged sectional view of FIG. 3 (l), FIG. 4 (a), ( b) and (c) are cross-sectional views showing different examples of the mounting manner of the elastic body employed in the present invention, and FIG. 5 is a partial cross-sectional view showing the contact state between the edge of the window glass and the mold in the test example. FIG. 6 is a partial cross-sectional view showing an example of a conventionally used molding die. In the figure, 1 to 8 are elastic bodies, 11 is a molding die, 12 is an upper die, 13 is a lower die, 14 is a cavity space, and G is a window glass.

Claims (3)

(57) [Claims] 1. A window glass with a gasket is produced by arranging a window glass in a molding die and injecting a gasket material into a gasket molding cavity space formed between a peripheral edge of the window glass and an inner surface of the molding die. In the method of manufacturing, an elastic body whose elastic modulus is changed according to the curvature accuracy of each portion of the window glass is arranged in a portion of the molding die that comes into contact with the window glass, and a contact surface with the window glass is provided through this elastic body. A method for manufacturing a window glass with a gasket, which comprises sealing. 2. The method for manufacturing a window glass with a gasket according to claim 1, wherein a plurality of elastic bodies having different elastic moduli are arranged in combination along a portion of the mold which contacts the window glass. 3. The method for producing a window glass with a gasket according to claim 1, wherein the Young's modulus of the elastic body is 1 to 5,000 kg / cm ² .