JPH0536146U - Bump cushion for vehicle absorber - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a bump cushion for a vehicle shock absorber that is unlikely to expand in the outer diameter direction when compressed. In a bump cushion 24 formed of a cylindrical elastic body, in which a piston rod insertion hole 28 is formed in the central axial direction, one end 24a is attached to the vehicle body side, and the other end 24b is attached to the outer periphery of the piston rod of a shock absorber with the other end being the wheel side, The inner diameter of the piston rod insertion hole 28, once enlarged on the vehicle body side, becomes smaller as it approaches the vehicle body side one end 24a, and is larger than the unincremented inner diameter at the vehicle body side one end 24a.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a bump cushion for a vehicle shock absorber, and more particularly to a bump cushion that reduces bulging in the outer diameter direction during compression.

[0002]

[Prior Art]

 A vehicle shock absorber 12 is attached to a suspension system for a vehicle body of an automobile or the like as shown in FIG. 4 in order to damp vibrations caused by unevenness of the road and ensure traveling stability. A bump cushion 18 (also referred to as a bound bumper or bump rubber) is attached to one end of the shock absorber 12 for the purpose of more effectively dampening and relaxing the shock.

The bump cushion 18 is made of a tubular elastic body having a piston rod insertion hole 19 formed in the central axial direction, and has one end on the vehicle body 11 side and the other end on the wheel (not shown) side. It is attached to the outer circumference. When the cylinder 22 of the shock absorber moves up and down largely, it is pressed by one end of the cylinder 22 and is compressed and deformed, so that the shock is attenuated and alleviated. In the figure, 10 is an upper spring seat, 16 is a coil spring, and 23 is an insulator.

By the way, the piston rod 14 may be thickened at the vehicle body side one end 14a in order to increase the strength of the mounting portion. Further, as shown in FIG. 5, the upper spring sheet 10 may be formed in an annular convex shape 10a that is convex downward around the piston rod 14 for reinforcement.

In order to prevent the attachment of the bump cushion 18 from being impaired even in such a case, the inside diameter of the piston rod insertion hole 19 is enlarged at one end 18a of the bump cushion 18 on the vehicle body side to enlarge the inside diameter. The thickened end portion 14a of the piston rod or the annular convex shape 10a portion of the upper spring seat is accommodated in the portion.

However, in the bump cushion 18, by enlarging the inner diameter of the piston rod insertion hole, the one end 18a on the vehicle body side is more likely to swell in the outer diameter direction during compression as shown by the chain double-dashed line in FIG. Then, the following problems occurred. That is, the spring characteristics are deteriorated, the bump cushion 18 comes into contact with a coil spring or the like, the durability of the bump cushion is deteriorated, or abnormal noise is generated due to friction with other parts when the bump cushion is expanded.

[0007]

[Problems to be solved by the device]

 Therefore, in view of the above points, the present invention provides a bump cushion that is unlikely to expand in the outer diameter direction during compression.

[0008]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention comprises a cylindrical elastic body having a piston rod insertion hole formed in the central axial direction and having one end on the vehicle body side and the other end on the wheel side attached to the outer periphery of the piston rod of the shock absorber. In the bump cushion, the inner diameter of the piston rod insertion hole is once enlarged on the vehicle body side and then becomes smaller as it approaches one end on the vehicle body side, and is larger than the inner diameter before the enlargement on one end on the vehicle body side. I did it.

[0009]

[Action]

 In the bump cushion, the inner diameter of the piston rod insertion hole is once enlarged on the vehicle body side and then becomes smaller as it approaches one end on the vehicle body side. Therefore, when the bump cushion is compressed, the bump cushion bends inward with the inner diameter enlarged portion of the piston rod insertion hole as a bending point. As a result, the bump cushion is prevented from expanding outward.

[0010]

【Example】

 An embodiment of the present invention will be described below. FIG. 1 is a sectional view of a bump cushion according to an embodiment of the present invention. The bump cushion 24 is formed by forming a piston rod insertion hole 28 in the central axial direction of a cylindrical elastic body 26 made of rubber or foam urethane elastomer. The inner diameter of the piston rod insertion hole 28 is once D near the vehicle body side end 24a of the bump cushion.₁As it gets closer to the vehicle body side one end 24a, it becomes smaller this time and becomes smaller at the vehicle body side one end 24a. ₃ Greater D₂It has become. That is, the inner diameter of the piston rod insertion hole 28 is D₃<D₂<D₁Have a relationship.

The optimum position for enlarging the inner diameter D of the piston rod insertion hole 28 is determined according to the size, shape, material of the bump cushion, the type of vehicle used, and the like. In the bump cushion 24 of this embodiment, the dimensions of each part are as follows. D ₀ = 50 mm, D ₁ = 35 mm, D ₂ = 30 mm, D ₃ = 18 mm, H ₀ = 40 mm, H ₁ = 10 mm.

Further, annular grooves 27 and 29 are appropriately formed on the outer surface and the inner surface of the tubular elastic body 26 in order to more effectively suppress the bulge in the outer diameter direction that occurs during compression.

In the bump cushion 24 thus formed, the piston rod of the shock absorber is inserted into the piston rod insertion hole 28, and the bump cushion 24 becomes a shock absorber in the same manner as the conventional bump cushion 18 shown in FIG. Mounted. At this time, the bump cushion 24 is configured such that one end 24a on the vehicle body side is on the vehicle body side and the other end 24b is on the wheel side.

FIG. 2 is a sectional view showing the bump cushion 24 when compressed. When the bump cushion 24 is compressed, a vertical force is first applied to the inner surface of the piston rod insertion hole 28 as shown in (a). Next, as shown in (b), the bump cushion 24 bends inward at the inner diameter enlarged portion 28a of the piston rod insertion hole 28. As a result, the bulge of the bump cushion in the outer diameter direction is suppressed.

FIG. 4 is a sectional view of a bump cushion according to another embodiment of the present invention. The bump cushion 30 is formed by enlarging the inner diameter D of the piston rod insertion hole 32 by forming the inner surface of the piston rod insertion hole 32 into a V-shaped cross section at a portion 32a near the one end 30a on the vehicle body side. This bump cushion 30 is also used in the same manner as the bump cushion 24 of the above embodiment.

[0016]

[Effect of the device]

 Since the bump cushion of the present invention has the above-mentioned structure and can reduce the bulge in the outer diameter direction at the time of compression, the spring characteristic can be improved. In addition, it is possible to prevent a decrease in durability caused by buffering (contact) with other components due to bulging, and to reduce abnormal noise caused by rubbing with other components when bulging.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a bump cushion according to an embodiment of the present invention.

FIG. 2 is a sectional view illustrating a compressed state of a bump cushion according to an embodiment of the present invention.

FIG. 3 is a sectional view of a bump cushion according to another embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a mounted state of a conventional bump cushion.

FIG. 5 is a sectional view of an upper spring seat.

FIG. 6 is a cross-sectional view showing a compressed state of a conventional bump cushion.

[Explanation of symbols]

 24 Bump cushion according to one embodiment of the present invention 24a One end of the bump cushion on the vehicle body side 26 Cylindrical elastic body 28 Piston rod insertion hole 28a Enlarged inside diameter of piston rod insertion hole 30 Bump cushion according to another embodiment of the present invention

Claims (1)

[Scope of utility model registration request] 1. A bump cushion made of a cylindrical elastic body, in which a piston rod insertion hole is formed in a central axial direction, one end of which is a vehicle body side, and the other end of which is a wheel side and which is attached to the outer periphery of a piston rod of a shock absorber. After the inner diameter of the insertion hole is once enlarged on the vehicle body side, it becomes smaller as it approaches the one end on the vehicle body side, and at the one end on the vehicle body side it is larger than the inner diameter before the expansion. Bump cushion.