JPH0538946A - Automotive weatherstrip - Google Patents

Abstract

PURPOSE:To prevent a weatherstrip from swelling and waving at the time of washing an automobile by a wax remover so as to keep the appearance thereof and sealing function desirable by improving the oil resistance of vulcanized rubber forming the seal lip of the weatherstrip. CONSTITUTION:The outer surface 10 or the whole of a seal lip 9 exposed to washing by a wax remover is formed of the mixture of EPDM and NBR mixed at a required mixing ratio so as to be excellent in oil resistance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a weather strip for an automobile, which is mounted on the outer peripheral edge of a vehicle door or the peripheral edge of a body opening to seal a gap between the door and the body.

[0002]

2. Description of the Related Art Usually, a seal is provided on an outer peripheral edge of a door frame (3) in order to seal a gap between an opening (1) of a body (1) and a door (2) of a passenger car (C) as shown in FIG. The rubber weather strip mounted as a member seals a portion where the gap is likely to change due to an error in the mounting accuracy of the door (2) itself, a door suction phenomenon due to a load during high-speed traveling, and the like. A high level of sealing performance to prevent the entry of rainwater and the like, and accurate mounting and fixing of the weather strip itself are required.

As the weather strip, generally, a fitting portion fitted to a gutter-shaped retainer provided on an outer peripheral edge of a door frame of a door hinged at one end to a body opening of the automobile, and a door. A hollow main seal part that abuts against the inner corner of the opening of the body panel when closed and is deformed, and a tongue-shaped seal lip whose tip abuts the roof drip of the outer corner of the body panel integrally provided, Alternatively, in an automobile using a press door, a fitting portion that is fitted to a drip channel formed in a T-shaped cross section on the body side, and the fitting portion that is integrally extended from the fitting portion and that is closed when the door is closed. A member having a tongue-shaped seal lip that seals these gaps by interposing them between the bodies is often used. Since these conventional weather strips are exposed to wind and rain or sunlight as described above, they are usually made of ethylene propylene rubber (hereinafter referred to as EPDM) which is excellent in weather resistance, aging resistance and ozone resistance. There is.

[0004]

By the way, an automobile is stored with its surface protected by a dedicated wax from its completion to its sale. This protective wax is washed off with a wax remover at the time of sale.
Since the above-mentioned automobile is normally washed under high pressure with this wax remover composed of white kerosene and steam, the seal lip of the weatherstrip made of EPDM is swollen and corrugated to produce an appearance of the weatherstrip. There is a problem that the sealing function is deteriorated at the same time as being damaged.

The present invention copes with the above situation and improves the oil resistance of the vulcanized rubber itself forming the seal lip of the weatherstrip, so that the weatherstrip can be prevented from swelling and waviness at the time of cleaning by the wax remover. The purpose is to prevent it and maintain its appearance and sealing function well.

[0006]

SUMMARY OF THE INVENTION The features of the present invention, which meet the above-mentioned object, are as follows: a fitting portion fitted to a retainer of a door frame, a drip channel on the body side, or the like;
A weather strip for an automobile, comprising: a tongue-shaped seal lip that is integrally extended from the fitting portion and that intervenes between the door and the body when the door is closed to seal a gap between them. This is because a solid rubber layer having a mixture of EPDM and acrylonitrile butadiene rubber (hereinafter referred to as NBR) as a base material was formed on the outer surface. A second aspect of the present invention is characterized in that the sealing lip of the weather strip is formed of foamed rubber whose base is a mixture of EPDM and NBR.

Here, EPDM and N used in the present invention are used.
It is essential that the mixing ratio of BR be in the range of 8: 2 to 2: 8 by weight. In addition, the mixture contains other rubber components such as natural rubber (NR), styrene-butadiene copolymer rubber (SBR), polybutadiene rubber (BR), polyisoprene rubber (IR ), Chloroprene rubber (CR), butyl rubber (IIR) and other resin components such as polyethylene (PE), polypropylene (P)
R), ethylene-vinyl acetate copolymer (EVA) and the like are also included. In this case, the content of the other rubber component is usually not more than 1/2 weight of the mixture of EPDM and NBR.

The EPD forming a seal lip
In the mixture of M and NBR, a compound usually used, that is, sulfur, morpholine, disulfide, as a vulcanizing agent,
2-cumcaptobenzothiazole, zinc dimethyl-dithiocarbamate, tetramethylthiutim disulfide, etc. as a vulcanization accelerator, dicumyl peroxide, aging inhibitor, antioxidant, phenyl-α-naphthylamine as an ozone deterioration inhibitor, 2. It goes without saying that 6-di-t-butyl-p-cresol, etc., carbon, hydrous silicic acid, magnesium carbonate, clay, etc. as a filler, dioctyl sebacade, mineral oil etc. as a plasticizer are used as necessary. Absent.

In the production of the weather strip for automobiles of the present invention, however, a foaming agent is added to the compound containing the mixture of EPDM and NBR as a base material, followed by continuous extrusion vulcanization molding or compression, injection molding or the like. The entire sealing lip is manufactured as a sponge body by molding, or is molded by the same molding means without adding a foaming agent to form a solid rubber layer on the outer surface of the sealing lip.

[0010]

In the weather strip for automobiles of the present invention having the above-mentioned structure, the outer surface of the seal lip or the entire seal lip exposed to the washing by the wax remover of the automobile is made into a mixture of EPDM and NBR having a required mixing ratio excellent in oil resistance. With this structure, it is possible to prevent the weather strip from swelling and waviness due to the wax remover, and to maintain its appearance and sealing function well.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a sectional view showing a weatherstrip for an automobile according to a first embodiment of the present invention. This weatherstrip is a door (2) hinged at one end to an opening of an automobile body (1). A fitting part (5) fitted in a gutter-shaped retainer (4) provided on the outer peripheral edge of the door frame (3),
When the door is closed, the hollow cylindrical main seal portion (7) is deformed by abutting the inner corner of the opening of the body panel (6), and the tip end of the rubber roof drip (8) at the outer corner of the body panel (6). Tongue-like seal lip (9) that abuts
And are integrated into one.

In this weather strip, a solid rubber layer (10) having a base material of a mixture of EPDM and NBR (mixing ratio 8: 2 to 2: 8 weight) is formed on the outer surface of the seal lip (9). In addition, the other part except the rubber layer (10) is made of foamed rubber having EPDM as a base material.

On the other hand, FIG. 2 shows a weather strip according to the second embodiment of the present invention, which is a so-called roof side rail weather strip used in an automobile using a press door (11). , A fitting portion (13) fitted to a drip channel (12) provided in a T-shaped cross section on the body (1) side, and extending integrally from the fitting portion (13), when the door is closed. It is provided with two tongue-shaped seal lips (14) and (15) which are interposed between the door (11) and the body (1) to seal these gaps.

In the weather strip of this embodiment, the two seal lips (14) and (15) are made of EP.
Foamed rubber based on a mixture of DM and NBR (mixing ratio 8: 2 to 2: 8 weight), and the fitting part (13) is EPD.
Each is made of solid rubber having M as a base material.
Both of the seal lips (14) and (15) are formed of a mixture of EPDM and NBR as a base material for manufacturing reasons, but only the seal lips (14) exposed outside the vehicle when the door is closed. It is also possible to form by the said base material.

The first and second embodiments of the present invention having the above-mentioned structure will be described in more detail in accordance with specific manufacturing methods, and the characteristics thereof will be compared with a comparative example using EPDM as a base material.

First, the seal lips (or a part thereof) of the first embodiment and the second embodiment are respectively tested in Experimental Example 1 shown in Table 1 below.
In addition to the composition having the composition described in Experimental Example 2 and Experimental Example 3, the seal lip of the conventional example using EPDM as the base material was composed of the composition having the composition described in Comparative Examples 1 and 2 in the same table. Margin below

[0018]

[Table 1]

The weather strips of Experimental Examples 1 and 2 and Comparative Example 1 having the seal lip having the above composition are in the form of the first embodiment, and the weather strips of Experimental Example 3 and Comparative Example 2 are the second embodiment. In the form of coextrusion respectively. The characteristics are shown in Table 2.

[0020]

[Table 2]

From the above results, the weather strip of the present invention having the seal lip whose base material is a mixture of EPDM and NBR in a required mixing ratio has normal physical properties and weather resistance as compared with the conventional one having EPDM as a base material. Swelling of the weatherstrip during cleaning with the wax remover of automobiles due to its excellent resistance to oil and oil resistance
It is possible to prevent waving, and to maintain its appearance and sealing function very well as compared with the conventional one.

[0022]

As described above, in the automotive weather strip of the present invention, both the outer surface of the seal lip exposed to the cleaning by the wax remover or the entire seal lip is EPDM and N of the required mixing ratio excellent in oil resistance.
It is composed of a mixture of BR, and by such a structure, it is possible to prevent the weather strip from swelling and waviness due to the white kerosene of the wax remover, and to maintain its appearance and sealing function extremely well as compared with the conventional one. In addition to the above-mentioned effects, the seal lip is excellent in normal-state physical properties and weather resistance as compared with the conventional products, so that the weather strip can have a long life and its practical value is very high.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention.

FIG. 2 is a sectional view showing a second embodiment of the present invention.

FIG. 3 is a perspective view of an automobile.

[Explanation of symbols]

 (1) Body (2) (11) Door (3) Door frame (4) Retainer (5) (13) Fitting part (6) Body panel (7) Main seal part (8) Roof drip (9) (14) ) (15) Seal lip (10) Solid rubber layer (12) Drip channel

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI technical display location // B29L 31:30 4F (72) Inventor Hirokuni Kitabayashi Miyoshi-cho, Nishikamo-gun, Aichi Ichiga Yama No. 3 Toyo Tire & Rubber Co., Ltd. Automotive Parts Technology Center

Claims (2)

[Claims] 1. A fitting portion that is fitted to a retainer of a door frame, a drip channel on the body side, and the like, and extends integrally from the fitting portion, and is interposed between the door and the body when the door is closed. A weather strip for an automobile provided with a tongue-shaped seal lip for sealing these gaps, wherein a weight ratio of ethylene propylene rubber and acrylonitrile butadiene rubber is 8: 2 to the outer surface of the seal lip.
A weather strip for an automobile, comprising a solid rubber layer having a 2: 8 mixture as a base material. 2. A fitting portion that is fitted to a retainer of a door frame, a drip channel on the body side, or the like, and extends integrally from the fitting portion, and is interposed between the door and the body when the door is closed. A weather strip for an automobile having a tongue-shaped seal lip for sealing these gaps, wherein the seal lip is a weight ratio of ethylene propylene rubber and acrylonitrile butadiene rubber of 8: 2 to 2: 8.
A weather strip for an automobile, characterized in that it is formed from foamed rubber having a mixture of the above as a base material.