JPH11153176A - Bumper rubber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent generation of noise when bound is inputted by forming a bumper rubber for a surface which is brought into contact with a damper rod and/or an upper sheet as a low frictional rubber. SOLUTION: A bumper rubber A is constituted by arranging a low frictional rubber 2 in the vicinity of a surface which is brought into contact with an upper sheet 13 and/or a damper rod 12 on a bumper rubber main body 1. A diameter of a rod inserting hole of the low frictional rubber 2 is formed smaller compared with that of the inserting hole 3 of the rubber main body 1. Since a part of the bumper rubber A is made of low frictional rubber if rubbing movement toward a relatively rotational direction between the damper 11 and an upper surface of the upper sheet 13 and the bumper rubber 1 and/or rubbing movement of a relatively axial direction between an inserting hole inner circumferential surface and a rod in association with compressive deformation of the bumper rubber 1 are/is generated when bound is inputted, the part is slid smoothly so as to prevent generation of noise.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bumper rubber used for a suspension device of a vehicle or the like and used for abutting a damper body.

[0002]

2. Description of the Related Art In a vehicle suspension system, as shown in FIG. 3, a damper rod (12) protruding from a damper body (11) expands and contracts with the damper body (11), so that the fluid resistance in the damper body is reduced. Vibration is damped. FIG. 3 shows the vicinity of the upper portion of a suspension device to which a conventionally known bumper rubber (10) is applied. In this suspension device,
The damper rod (1) protruding from the damper body (11)
A bumper rubber (10) is loosely fitted and inserted into the rod (12) near the front end of the upper sheet (1).
It is fitted and attached to the attachment cylinder (13A) provided in 3). The bumper rubber (10) has a large impact between the damper body (11) and the damper rod (12) when a sudden or strong impact force that cannot be absorbed by the damper body (11) and the coil spring (14) is applied. Due to the relative displacement, the bumper rubber (10) comes into contact with the damper body (11). At this time, the vehicle body side member (see FIG. (Not shown) and damper body (1
It functions to effectively prevent the impact of 1) from being directly transmitted.

[0003] The bumper rubber (10) has a substantially cylindrical shape as a whole, and is mostly made of a single material such as rubber, a rubber-like elastic material, or a foam material, and has a soft spring constant under a low load. However, when the load is high, a hard spring constant is required. However, in a suspension device equipped with such a bumper rubber,
When the damper body (11) comes into contact with the bumper rubber (10) due to a large relative displacement between the damper body (11) and the damper rod (12), that is, when a bump impact force is input, the bumper rubber ( 10) undergoes compressive deformation, and further, in this state, when a relative rotation direction is input to the damper body (11) side, the bumper rubber (1) is pressed.
The bumper rubber (10) is connected to the upper sheet (13) at the portion where the upper sheet (0) is joined to the upper sheet (13).
Abnormal noise is generated between the upper sheet (13) and the bumper rubber (10) by rubbing while being pressed along the surface, and the bumper rubber (10) expands in a direction orthogonal to the compression direction to cause the damper rod (12). ) And the inner peripheral surface of the bumper rubber (10) in close contact with each other. In this state, the damper rod (12) and the bumper rubber (10) relatively rub against each other due to the compression deformation of the bumper rubber (10). There was a problem that an unusual noise was generated, giving the passenger discomfort.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to prevent occurrence of abnormal noise at the time of a bounce input in view of the above-mentioned prior art.

[0005]

Means for Solving the Problems In order to achieve the above object, the present invention is characterized in that "the bumper rubber on the surface in contact with the damper rod and / or the upper sheet is made of low friction rubber". That is, the bumper rubber of the present invention is not constituted by a single material, but is constituted by a plurality of different materials, and the low-friction rubber material of the bumper rubber on the surface in contact with the damper rod and / or the upper sheet. NR (natural rubber), NR (natural rubber) / BR (polybutadiene rubber)
Blend rubber, NR (natural rubber) / SBR (styrene butadiene rubber) blend rubber, styrene butadiene rubber, chloroprene rubber, isoprene rubber, ethylene propylene rubber, butyl rubber, acrylonitrile butadiene rubber, etc., and low friction such as oleic acid and stearamide It can be obtained by blending a compound imparting properties. Of course, the low friction imparting compound is not limited to these.

[0006] The rubber material of the bamber rubber body is usually a natural rubber, styrene butadiene rubber, chloroprene rubber, isoprene rubber, or the like generally used.
Crosslinked rubber such as ethylene propylene rubber, butyl rubber, acrylonitrile butadiene rubber, silicon rubber, urethane rubber, fluorine rubber, halogenated butyl rubber, hydrogenated NBR (nitrile butadiene rubber), chlorosulfonated polyethylene, and polyolefin, polyester, and polyether Selected from thermoplastic elastomers such as polyamide-based and polyurethane-based thermoplastic rubbers (edited by Haruhiko Tohara, "Revised New Edition Anti-vibration Rubber" (Showa 50-8.15) Japan Railway Vehicle Industry Association, p. 41-p. 43 ).

The method of manufacturing the bumper rubber according to the present invention includes the following steps. (1) A bumper rubber main body and a surface contacting with a damper rod and / or an upper sheet are separately molded and vulcanized, and they are joined and integrated. Assemble. (2) Simultaneously integrally vulcanize the surface of the bumper rubber body and the surface contacting the upper sheet and / or the damper rod. And the like. However, the manufacturing method (2) greatly contributes to improvement in productivity by saving labor in the manufacturing process. As an example of the simultaneous integral molding vulcanization method, a mold for forming a bumper rubber is prepared, and at least two locations of an injection port for injecting low friction rubber and an injection port for injecting the bumper rubber body rubber into the mold. An injection port is provided, and injection molding is performed almost simultaneously from each injection port and vulcanized. For injection and vulcanization, the injection amount, injection pressure, temperature (rubber, mold, etc.), blending and the like are appropriately set.

In order to constitute the low friction rubber of the present invention, the NR (natural rubber), NR (natural rubber) /
Low friction properties such as BR (polybutadiene rubber) blend rubber, NR (natural rubber) / SBR (styrene butadiene rubber) blend rubber, styrene butadiene rubber, chloroprene rubber, isoprene rubber, ethylene propylene rubber, butyl rubber, acrylonitrile butadiene rubber, etc. 0.5 PHR to 35 PHR, preferably 2 PHR
２５25 PHR, blended. If the compounding amount of the low friction imparting compound is less than 0.5 PHR, the low friction property is not sufficiently exhibited, and if it exceeds 35 PHR, the bumper rubber (A)
Decreases toughness and durability. According to the present invention, by setting the low friction imparting compound to 0.5 PHR to 35 PHR, preferably 2 PHR to 25 PHR, it is possible to completely prevent abnormal noise generated at the time of bound input and to improve productivity by simultaneous integral vulcanization. Can greatly contribute to the improvement of. .

[0009]

Embodiments of the present invention will be described below in more detail with reference to the drawings. However, the present invention is not limited by these embodiments. FIG. 1 shows an embodiment of the present invention in which a surface in contact with an upper sheet and / or a damper rod is provided with low-friction rubber, and FIG. 2 shows another embodiment of the present invention in which the upper sheet and / or the damper rod comes into contact with the upper sheet and / or the damper rod. An example in which a low friction rubber is arranged on the entire upper part is shown.

Embodiment 1 FIG. 1 shows the vicinity of an upper portion of a suspension device to which a bumper rubber (A) of the present invention is applied. In this suspension device, a damper rod (12) is inserted into a cylindrical damper body (11) having a vertical axis, and a piston (not shown) is attached to a lower end of the damper rod (12). I have. The piston is provided with a through hole. When the piston moves, the working fluid sealed in the damper body (11) moves through the through hole so that the vibration is attenuated by viscous resistance. It has become. Vibration is transmitted to the lower end of the damper body (11) from the wheels of an automobile. An upper sheet (13) is loosely fitted and inserted into the upper end of the damper rod (12). The upper seat (13) is partially connected to the vehicle body (not shown) so as to be able to support a load from wheels. The upper sheet (13) corresponds to the lower sheet (20) fixed to the outer periphery of the damper body (11).
0), a coil spring (14) is interposed between the coil spring (14) and the damper rod (12).
The urging force is being applied in the direction of pulling out from. The tip of the upper end of the damper rod (12) is connected to a strut mount (not shown), and is connected to the vehicle body via the strut mount.

In the first embodiment shown in FIG. 1, the bumper rubber (A) includes an upper sheet (13) and / or a damper rod (12) attached to the bumper rubber body (1).
Low friction rubber (2) is arranged near the surface that comes in contact with the bumper rubber (A) and the rod insertion hole (3)
, A low-friction rubber (2) is disposed on the inner peripheral surface on the upper end side having a smaller diameter than the others. The low friction rubber (2) may be provided on the outer peripheral portion corresponding to the mounting cylinder portion (13A), or may be provided so as to abut the damper rod (12) on the inner periphery of the rod insertion hole (3). If there are other parts, they are preferably provided there. The bumper rubber body (1) uses NR (natural rubber) / SBR (styrene butadiene rubber) blend rubber, and the low friction rubber (2)
NR (natural rubber) / SBR (styrene butadiene rubber)
The blended rubber is mixed with 20 PHR of stearic acid amide as a low friction imparting compound, and the bumper rubber body (1) and the low friction rubber (2) are separately molded and vulcanized, and the low friction rubber (2) is bumper rubber. It is joined to the main body (1). Bumper rubber (A) according to the present invention
Is mounted by being fitted to a mounting cylinder (13A) provided on the upper sheet (13). In addition, this mounting cylinder part (13A) is provided with the upper sheet (1).
It may be composed of a member different from 3) and fixed to the upper sheet (13).

Embodiment 2 FIG. 2 shows the vicinity of an upper portion of a suspension device to which a bumper rubber (A) of another embodiment of the bumper rubber of the present invention is applied. This bumper rubber (A) is provided with an upper sheet (13) and / or a damper rod (1).
A low-friction rubber (2) is arranged on the entire upper part in contact with 2), and the bumper rubber body (1) is N
R (natural rubber) / SBR (styrene butadiene rubber) blend rubber is used, and the low friction rubber (2) is a NR (natural rubber) / SBR (styrene butadiene rubber) blend rubber and stearic acid as a low friction imparting compound. An amide is compounded at 20 PHR, and a bamboo wrapper body (1) and a low friction rubber (2) are simultaneously integrally molded and vulcanized. As described above in detail, in the suspension device to which the bumper rubber according to the present invention is applied, the damper (11) and the upper seat (13) at the time of the bounce input.
Between the upper sheet (13) and the upper surface of the bumper rubber (1) in the direction of relative rotation between the upper sheet (13) and the upper surface of the bumper rubber (1) and / or the bumper rubber (1). Even if relative axial friction occurs between the inner peripheral surface of the insertion hole and the rod due to the compression deformation of the bumper rubber (A), since the corresponding portion of the bumper rubber (A) is made of low friction rubber, it slides smoothly. No abnormal noise was observed.
Depending on the configuration of the upper sheet, bumper rubber, damper rod, etc., the location and shape of the low-friction rubber are in the technical scope of the present invention in response to the occurrence of abnormal noise being different. It goes without saying that you enter.

[0013]

As is apparent from the detailed and concrete description, the bumper rubber according to the present invention has the above-described configuration, so that the generation of abnormal noise is eliminated, and the passenger is provided with
An extremely excellent effect that a comfortable ride can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic diagram for explaining a suspension device to which an example of a bumper rubber of the present invention is applied.

FIG. 2 is a schematic diagram for explaining a suspension device to which another example of the bumper rubber of the present invention is applied.

FIG. 3 is a diagram illustrating the vicinity of an upper portion of a suspension device to which a conventionally known bumper rubber is applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS A Bumper rubber 1, 10 Bumper rubber main body 2 Low friction rubber 3 Rod insertion hole 11 Damper main body 12 Damper rod 13 Upper seat 13A Mounting cylinder part 14 Coil spring 20 Lower seat

Claims (1)

[Claims] 1. A damper body for abutment,
A cylindrical bumper rubber having a damper rod insertion hole, wherein a bumper rubber attached to a mounting portion provided on an upper sheet has a contact contact surface with a damper rod and / or a contact with an upper sheet. Bumper rubber characterized in that the contact surface is made of low friction rubber.