JPH1037920A - Easy-fitting molded article and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely fit a main body in a molding into a mounting part in a counterpart member with ease by means of slight pressing force by fixing a locking body made of rubber material, whose substantially whole surface is impregnated with lubricant, in the position corresponding to the mounting part in the counterpart member. SOLUTION: A grommet A serving as an easily fittable molding is forcibly fitted in a mounting part (c) serving as an insertion hole in a counterpart member (b) such as a panel in an automobile. The grommet A is constructed of a main body 1 and a locking body 3, and the locking body 3 is fixed in the position corresponding to the mounting part (c) in the counter part member (b) in the main body 1 and is made of rubber group material whose substantially whole surface is impregnated with a lubricant 2. In installation of the molding A to the mounting part (c) in the counterpart member (b), the locking body 3 brought into contact with the mounting part (c) is smoothly inserted into the mounting part (c) without any resistance so as to be fitted when the molding A is pressed inward from its one side by means of a finger and the like, as the whole surface of the locking body 3 is impregnated with the lubricant 2 which exhibits a lubricating action.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an easy-fitting molded article which can be easily and securely fitted to a mounting portion of a mating member, and a method of manufacturing the molded article.

[0002]

2. Description of the Related Art Conventionally, for example, in the automobile manufacturing industry, a rubber part (grommet) having flexibility and elasticity is generally used as a holding member when attaching an automobile part to a frame panel or the like. At the time of mounting, as shown in FIG. 4, the grommet 50 is pushed into the mounting hole 52 of the panel 51 from the direction of the arrow, so that the flange portion 53 of the outer end portion is provided.
The panel 51 is sandwiched between the grommet 50 and the projection 54 to fix the grommet 50.

However, the mounting of the grommet 50 is performed by allowing the protruding piece 54 to pass from one side of the mounting hole 52 of the panel 51 to the other side through the inner peripheral edge thereof due to its elasticity. The protruding piece 54 of the rubber grommet 50 generates a large insertion resistance due to friction with the panel 51, and manually attaching the large number of panels 51 to the panel 51 gives a large labor burden to the operator.

Further, forcible press-fitting due to insertion resistance causes damage to the grommet 50 and incomplete mounting of main automobile parts. And other various problems.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and is directed to a molded product which is fitted to a mounting portion of a mating member by press-fitting. An easily fittable molded body and an easily fittable molded body that can be easily and reliably attached to a counterpart member by molding a locking body made of a material by impregnating a substantially entire surface thereof with a lubricant. The purpose of the present invention is to provide a manufacturing method.

[0006]

Means of the present invention for achieving the above object are a molded article which is fitted by press-fitting into a mounting portion of a mating member, and includes a main body and a mating member of the main body. An easy-fitting molded body is provided, which is fixed to a position corresponding to the mounting portion, and has a locking body made of a rubber material impregnated with a lubricant over substantially the entire surface thereof.

And a step of forming a locking member from a primary material obtained by kneading a rubber-based material and a lubricant in an easily fittable molded body including a main body and a locking member; Forming a main body from a secondary material made of a rubber-based material after inserting the locking body into a molding die, and integrally forming the locking body and the main body. The present invention relates to a method for manufacturing a fitting molded body.

[0008]

The present invention configured as described above has the following effects.

First, a rubber-based material and a lubricant are kneaded to obtain a primary raw material, which is used to form an engaging body.

Next, the locking body is inserted into a molding die, a secondary material made of a rubber-based material is injected into the molding die, a predetermined main body is formed, and the locking body and the locking body are formed. By forming the main body integrally, an easily fittable molded body is molded.

When the molded body is attached to the mounting portion of the mating member by pushing it in from one side with a finger or the like, the engaging body abutting the mounting portion is impregnated with the lubricant over substantially the entire surface. This lubricant has a lubricating effect,
It is smoothly inserted into the mounting portion without resistance, and is fitted to the mounting portion.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an embodiment of an easy-fitting molded article and a method for producing the molded article according to the present invention.

In FIG. 1, FIG. 3, and FIG. 4, A is an easy-fitting molded body, which is used as a holding member or an intermediate member in attaching an article to a mating member. For example, a grommet or packing in various industries is used. , O-ring, gasket, bush, etc. In this embodiment, a grommet for an automobile part will be described.

The grommet A, which is an easily fittable molded body.
As shown in FIG. 3, a main body 1 is fitted into a mounting portion c which is an insertion hole of a mating member b such as a panel of an automobile by press-fitting. And a locking member 3 made of a rubber material impregnated with a lubricant 2 over substantially the entire surface thereof.

The above-mentioned main body is formed by molding a polyolefin rubber, for example, an elastic rubber material such as EPDM (ethylene-propylene diene terpolymer), as shown in FIGS. 2 (b) and 2 (c). It is formed by a mold 4 (described later), and is formed in a substantially tapered shape in which a hollow portion 5 for holding an article (not shown) is provided in the inside of a cylindrical shape. A flange 6 which is in contact with one side surface of the counterpart member b is provided on the large diameter side.

The locking member 3 is formed in a flange shape with a diameter larger than the inner diameter of the mounting portion c, which is an insertion hole of the mating member b, and can be arbitrarily flexible in the insertion hole c. It has elasticity, and has a gap 7 between the flange 6 and the side surface of the locking body 3 for holding the mating member b with a predetermined elasticity.

The locking member 3 is connected to the main body 1 described above.
Polyolefin rubber which is a rubber material similar to that described above, for example, EPDM (ethylene-propylene terpolymer), and ester oil which is a lubricant 2, for example,
Octyl pyromellitic acid and ester oil 15 to 100 parts by weight of polyolefin rubber
Forty parts by weight, preferably 30 parts by weight, are blended, and a primary raw material is obtained by a conventional kneader, and injection molding, press molding, transfer molding, etc. are performed in a molding die 8 as shown in FIG. The ester-based oil 2 which is a lubricant is impregnated into at least almost the entire surface of the polyolefin rubber uniformly.

If the content of the ester oil 2 is less than 15 parts by weight, a sufficient lubricating effect cannot be obtained due to a decrease in the content thereof. And the amount of oil seeping out is large, which causes contamination near the time of use, and the degree of fixation to the mating member b decreases.

In this molding, the vulcanization temperature is 160 ° C. to 170 ° C., preferably 1
At 65 ° C., the vulcanization time is 2 minutes to 6 minutes, preferably 3 minutes.
Vulcanization molding is performed according to the conditions of minutes.

In the molding of the main body 1 described above,
As shown in FIG. 2 (b), after the locking body 3 molded by the above-described method is inserted into the molding die 4, the second raw material polyolefin rubber is vulcanized by a conventional molding method. Temperature 160-170 ° C., preferably 165
Depending on the temperature, the vulcanization is performed for 4 to 8 minutes, preferably for 6 minutes.

Then, the inner peripheral surface of the locking body 3 and the outer peripheral surface of the main body 1 are bonded by vulcanization by a chemical reaction, as shown in FIGS. 1 and 2 (c). Strongly integrated together.

The connection between the main body 1 and the locking body 3 is as follows.
A conventional adhesive may be used other than the insert molding described above.

(Example) In molding a grommet as an automobile part, octyl pyromellitic acid ester (Asahi Desica) was used as a primary raw material with respect to 100 parts by weight of EPDM (Mitsui Petrochemical Co., Ltd., product name: Mitsui EPT-3045E). Manufactured by Adeka UL-80) (30 parts by weight).

At a vulcanization temperature of 165 ° C. in a mold,
Vulcanization molding was performed for 3 minutes to obtain a locking body corresponding to an automobile panel.

After inserting this locking body into a molding die, it was vulcanized at a vulcanization temperature of 165 ° C. for 6 minutes to form a grommet.

After a lapse of 30 minutes from the molding, an oil component, which is a component of octyl pyromellitic acid, oozed out from the surface of the locking body.

The grommet A thus formed and the conventional (comparative) grommet 50 are compared with each other in terms of the insertion force of the locking member 3 and the projecting piece 54 into the mounting holes c and 52 of the panels b and 51. The test was performed.

The mounting holes c and 52 of the panels b and 51 and FIG.
4 and the outer shape D in FIG. 4 are both set to φ18.

The insertion force was obtained by pulling the small-diameter portion side of each of the grommets A and 50 in the direction indicated by the arrow p in FIG. 3, and the values of five repeated tests and the average value were obtained. Was.

[0030]

[Table 1]

As is clear from Table 1, it can be seen that in this embodiment, the insertion force into the panel is reduced by 30% as compared with the comparative example. Pushing into the finger can be easily performed by a simple force, and does not give a burden to a finger or the like.

[0032]

As described above, according to the present invention, a locking member made of a rubber-based material having substantially the entire surface impregnated with a lubricant is provided at a position corresponding to a mounting portion of a mating member in a main body of a molded body. By fixing, the mating member can be easily and reliably fitted to the mounting portion by a light pushing force.

Therefore, there is no occurrence of poor fitting of the molded body to the mounting portion, and no damage to the molded body due to excessive press fitting with resistance. And so on.

[Brief description of the drawings]

FIG. 1 is a perspective view of an embodiment of an easy-fitting molded body employing a method for manufacturing an easy-fitting molded body according to the present invention.

FIG. 2 is an explanatory diagram showing a schematic forming step of the formed body in FIG.

FIG. 3 is a cross-sectional view showing a fitted state of the molded body in FIG.

FIG. 4 is an explanatory view showing a conventional rubber part.

[Explanation of symbols]

 A molded body b mating member c mounting part 1 main body 2 lubricant 3 locking body

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location B29L 31:30

Claims (2)

[Claims] 1. A molded body to be fitted by press-fitting into a mounting portion of a mating member, wherein the molded body is fixed to a main body and a position corresponding to the mounting portion of the mating member in the main body, and a lubricant is applied to substantially the entire surface thereof. An easily fittable molded body, comprising: a locking body made of a rubber-based material impregnated therein. 2. A step of forming an engaging body from a primary material obtained by kneading a rubber-based material and a lubricant in an easily fittable molded body comprising a main body and an engaging body; Forming a main body from a secondary material made of a rubber-based material after inserting the locking body into a molding die, and forming the locking body and the main body integrally. A method for producing an easily fittable molded article.