JPH0533646B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention provides an extruded glass run with
This invention relates to a method of forming corner portions by injection molding.

BACKGROUND ART Conventionally, as a method for forming corner portions in a glass run, the method shown in FIGS. 4 and 5 has been proposed (see Japanese Patent Laid-Open No. 59-67035). That is, the glass run 1 is made of rubber and has both side walls 2, 2 and a base wall 3 extending between the side walls 2, 2, as shown in FIG. The tip portion is provided with lips 4, 4 that come into close contact with both side surfaces of a door glass (not shown). When forming a corner portion in the glass run 1, first, as shown in the figure, the cutout portion 6 is formed by cutting out the cutout portion 5 extending over the both side walls 2, 2 and the base wall 3. Next, as clearly shown in FIG. 5, there is a lower mold 8 having a groove 7 and a mountain-shaped cross section corresponding to the corner portion, a protrusion 9 that fits into the groove 7, and side protrusions 10, 10.
Using a core mold 11 having a core mold 11, the uncut portions 12 remaining after cutting both side walls 2 of the glass run 1 are engaged with the projecting edges 10, 10 of the core mold 11.
Thereafter, this core mold 11 is assembled to the lower mold 8 by fitting the protrusions 9 into the grooves 7, and after covering the upper mold (not shown), a thermoplastic resin is injected into the notch 6 and hardened by cooling. . As a result, as shown in FIG. 6, the goslan 1 whose corner portions 13 are made of thermoplastic resin 14 is formed.

Problems to be Solved by the Invention However, when the inner periphery 13a of the corner portion 13 formed by such a conventional method is housed in a molding die, the lower mold having a chevron-shaped cross section Although the corner portion 13 is bent at a substantially right angle along the corner portion 8, when the corner portion 13 is removed from the lower mold 8 after being molded, the elastic restoring force of the rubber results in a curved shape as shown in FIG. For this reason, the seventh
As shown in the figure, when the glass run 1 is fitted into a substantially right-angled sash 15, the inner periphery 13a of the corner portion 13 cannot follow the sash 15, and a gap S is created between the sash 15 and the inner periphery 13a. There was a risk that the appearance of quality would deteriorate.

The present invention has been made in view of these conventional problems, and provides a method for forming a corner portion of a glass run, which makes it possible to form a corner portion that follows the right angle shape of a sash.

Means for Solving the Problems In order to solve the above problems, in the present invention, a notch is formed on the outer periphery of an extruded glass run, and the glass run is bent from the notch to form a cross-sectional peak. In the method of forming a corner part by injecting a thermoplastic resin into the notch by placing the thermoplastic resin in a mold having a lower mold having a shape, the corner part is formed by intruding into the inner periphery of the glass run corner part at the top of the lower mold having a chevron-shaped cross section. An acute-angled protrusion is provided to form a bent groove.

Operation In the above configuration, when the corner portion is injection molded using the molding die having the lower mold, the acute-angled protrusion provided on the lower mold enters the inner periphery of the corner portion to form a fold groove. Therefore, even if the glass run is taken out of the mold after the thermoplastic resin at the corner has hardened, the inner periphery of the corner will not be restored by the elastic force, but will bend approximately at right angles through the bent groove. It maintains its shape.

Embodiment An embodiment of the present invention will be described below with reference to the drawings. In other words, as shown in Figures 1 and 2,
The lower mold 16 has a mountain-shaped cross section with sloped surfaces 17 and 18 on both sides, and has a top portion 19 formed in the center. The upper surface of this lower mold 16 has both inclined surfaces 1
A groove 7 is formed across 7 and 18, and the groove 7
Curved recesses 20 and 21 are formed on both sides. The curved recesses 20 and 21 have the apex 19
Protrusions 22, 23 are formed along these edges, and the protrusions 22, 23 have an acute angle shape as shown in FIG. On the other hand, as already explained with Figure 4,
The glass run 1 has both side walls 2, 2 and the both side walls 2, 2.
and a base wall 3 extending between the side walls 2, 2.
Lips 4, 4 that come into close contact with a door glass (not shown) are provided at the tip of the door. When forming the corner portions on the glass run 1, first, as shown in the figure, the two side walls 2, 2 and the base wall 3 are formed.
The cutout 6 is formed by cutting off the section 5 extending over the area. Next, as clearly shown in FIG. 2,2 Uncut portion 12 remaining after excision
After that, this core mold 11 is assembled into the groove 7 of the lower mold 16 shown in FIG. Let it harden. As a result, as shown in FIG.
A glass run 1 is then molded. At this time, since the protrusions 22 and 23 are formed on the lower mold 16, the protrusions 22 and 23 are formed on the inner periphery 13a of the corner portion 13 by the clamping pressure of the mold when the thermoplastic resin 14 is injected. Even if the glass run 1 is removed from the mold after the thermoplastic resin 13 has hardened as a result of forming the bent grooves 24 on the inner periphery, the inner periphery 13a of the corner portion 13 will not bend due to the elastic force. It maintains its substantially perpendicularly bent shape through the bent groove 24 without restoring its shape. Therefore, it is possible to accurately follow the sash 15 (FIG. 7) bent at a substantially right angle without creating a gap S, to eliminate the deterioration in quality caused by the gap S, and to improve the appearance quality. This is possible.

Effects of the Invention As explained above, the present invention provides the following features:
An acute-angled protrusion was formed that entered the inner periphery of the glass run corner part to form a bent groove, and the corner part was injection molded using this lower mold. Therefore, even if the glass run is taken out of the mold after the thermoplastic resin has hardened, the inner periphery of the corner part will be difficult to restore due to elastic force, and will maintain the shape bent at a substantially right angle through the bent groove. . Therefore, the corner portion of the glass run can be bent at a substantially right angle to accurately follow the sash without creating a gap, thereby improving the appearance quality.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a lower mold according to an embodiment of the present invention, FIG. 2 is a sectional view taken along the line of FIG. 1, and FIG.
FIG. 4 is a perspective view showing a corner portion of a glass run molded according to the same embodiment. FIG. FIG. 6 is an exploded perspective view showing a method of forming a corner portion. FIG. 6 is a perspective view showing a corner portion of a glass run formed by a conventional forming method. FIG. be. 1...Glass run, 6...Notch, 8, 16...
...Lower mold, 13...Corner part, 14...Thermoplastic resin, 19...Top part, 22, 23...Protrusion, 24
...A crease.

Claims (1)

[Claims] 1. A notch is formed on the outer periphery of an extruded glass run, the glass run is bent from the notch and housed in a molding die having a lower mold with a chevron-shaped cross section, and a thermoplastic resin is filled in the notch. A method of molding a corner portion by injection, characterized in that the top of the lower die having a chevron-shaped cross section is provided with an acute-angled protrusion that penetrates into the inner periphery of the glass run corner portion to form a bent groove. Molding method.