JPH1135743A - Glass run - Google Patents

Abstract

(57) [Problem] To provide a glass run which is advantageous in terms of cost and can surely satisfy required performance in an actual vehicle. SOLUTION: Lip portions 4 are provided on both sides of a body portion 3 having a groove-shaped cross section.
Wherein the main body 3 and the lip 4 are formed of a material based on an olefin-based elastomer, and only the main body 3 has 5 to 20 watts.
t% talc is added.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass run for slidably supporting an elevating window panel provided on a side door of an automobile or the like.

[0002]

2. Description of the Related Art As a glass run of an automobile, rubber such as ethylene propylene rubber (EPDM) or a PVC elastomer is used as a base material to continuously maintain airtightness and watertightness with respect to a window panel. However, recently, olefin-based elastomers have been spotlighted from the viewpoint of recyclability, environmental protection, and cost, and some olefin-based elastomers have actually been used. Glass runs are available on the market.

[0003]

However, existing olefin-based elastomer glass runs have a high friction coefficient of the olefin-based elastomer itself, and a linear expansion coefficient as high as that of rubber such as EPDM. Repeated high-temperature and low-temperature tests (heat cycle tests) shrink at low temperatures and are not slippery at high temperatures and cannot be stretched. As a result, the glass run shifts in the direction of compressing itself against the door sash. There is a possibility that it will. Such “displacement” not only causes a deterioration in appearance, but also affects the performance as a glass run.

[0004] In order to improve the non-slip property of the olefin-based elastomer, it is conceivable to add a lubricant or the like. It is expensive and disadvantageous in terms of cost.

The present invention has been made by paying attention to such a conventional technique, and is to provide a glass run which is advantageous in terms of cost and which can surely satisfy the required performance of an actual vehicle.

[0006]

According to the first aspect of the present invention,
A glass run having a shape in which lip portions are formed on both sides of a body portion having a groove-shaped cross section, wherein the body portion and the lip portion are
It is formed of a material having an olefin-based elastomer as a base material, and 5 to 20 wt% of talc is added only to the main body.

Here, if the amount of talc is less than 5 wt%, the linear expansion cannot be sufficiently suppressed, and if it exceeds 20 wt%, the linear expansion can be considerably reduced and the cost can be reduced. The original performance of the material such as elongation decreases.

[0008] Although talc of 5 to 20 wt% is added only to the main body, the boundary between the main body and the lip does not need to be strict. And vice versa.

According to the first aspect of the present invention, since talc is not added to the lip portion, the lip portion has a rubber-like property, and the original adhesion of the lip portion to the window panel can be secured. In addition, since the main body occupying most of the glass run has a low coefficient of linear expansion due to the addition of talc, it is possible to suppress the occurrence of “displacement” during the heat cycle. Therefore, it is not necessary to add a lubricant or the like to prevent “shift”, which is advantageous in terms of cost. Further, since the lip portion, the main body portion, and the protective layer are all made of the same olefin-based material, they are compatible with each other, and they can be surely multilayer-extruded. In addition, the injection welding of the corner portion performed after the extrusion is also thermal welding using the same material, and there is no adverse effect due to the lubricant or the like, so that it is easy to secure the strength.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described with reference to FIGS. Reference numeral 1 denotes a glass run attached to a door sash of an automobile, which slidably supports an edge of a door window panel 2 that moves up and down.
The glass run 1 has a main body 3 having a groove shape (U-shape) in cross section.
And lip portions 4 formed on both sides thereof. Protective layers 5 and 6 are integrally formed on the surface of the lip portion 4 that comes into contact with the door window panel 2 and the bottom surface of the main body portion 3, respectively.

The protective layers 5 and 6 are made of an olefin resin, the lip portion 4 is made of only an olefin elastomer, and the main body 3 is made of an olefin elastomer.
Talc as a low linear expansion material which is a disc-shaped filler and polypropylene for maintaining rubber-like performance are added.

The specific composition of the main body 3 is as follows.

FIG. 2 shows an extruder of a molding line, in which the talc and polypropylene-added olefin-based elastomer are filled to form the main body 3. First extruder 7
And a second extruder 8 filled with an olefin-based elastomer to form the lip portion 4;
The present embodiment comprises a third extruder 9 filled with an olefin-based resin to form protective layers 5 and 6 on the surfaces of the three extruders. Is obtained.

The obtained glass run 1 was assembled on a door sash and subjected to a heat cycle test to measure the "shift" of the glass run 1 in the compression direction. The conditions of the heat cycle test were as follows:
-30 ℃ x temperature error within ± 2 ℃
7h, 20 ℃ × 0.5h, 80 ℃ × 15h, 20 ℃ ×
Four cycles were performed with 0.5 h as one cycle. Further, the glass runs of various comparative examples were also tested under the same conditions.

As shown in the results below, the glass run 1 of the present embodiment is composed of a glass run formed entirely of only the olefin elastomer used in the present embodiment (Comparative Example 1) and an existing olefin elastomer. Of glass run (Comparative Example 2). This is an effect of the glass run 1 of the present embodiment in which talc is added to the olefin-based elastomer of the main body 3. In addition, conventional EPDM with a high linear expansion coefficient
The displacement was smaller than that of the glass run (Comparative Example 3), and the same performance as that of the conventional PVC elastomer glass run (Comparative Example 4) having a low coefficient of linear expansion was obtained.

-Product of the present embodiment-6 mm / m (full length)-Comparative Example 1 (entirely made of olefin-based elastomer)-10 mm / m (full length)-Comparative Example 2 (entirely made of existing olefin-based elastomer)-12 mm / m (full length) Comparative Example 3 (entirely made of EPDM) -16 mm / m (full length) Comparative Example 4 (entirely made of PVC elastomer) -5 mm / m (full length) The glass run 1 of this embodiment is Since the material is not a material for reducing the friction coefficient of the material itself due to the addition of the lubricant, good welding strength can be obtained without deterioration of injection welding at the corners.

[0017]

According to the first aspect of the present invention, since talc is not added to the lip portion, the lip portion has rubber-like properties, and the original adhesion of the lip portion to the window panel can be secured. . Further, since the main body occupying most of the glass run has a low coefficient of linear expansion due to the addition of talc, it is possible to suppress the occurrence of displacement during a heat cycle. Therefore, it is not necessary to add a lubricant or the like to prevent displacement, which is advantageous in terms of cost. Further, since the lip portion, the main body portion, and the protective layer are all made of the same olefin-based material, they are compatible with each other, and they can be surely multilayer-extruded. In addition, the injection welding of the corner portion performed after the extrusion is also thermal welding using the same material, and there is no adverse effect due to the lubricant or the like, so that it is easy to secure the strength.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a glass run according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing an extruder.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Glass run 2 Door window panel 3 Main part 4 Lip part 5, 6 Protective layer 7, 8, 9 Extruder

Continued on the front page (72) Inventor Masao Owaki 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation

Claims (1)

[Claims] 1. A glass run having a shape in which lip portions are formed on both sides of a body portion having a groove-shaped cross section, wherein the body portion and the lip portion are formed of a material based on an olefin-based elastomer, and 5-2 only for the main body
A glass run to which 0 wt% of talc is added.