Land vehicles – Wheeled – Running gear
Reexamination Certificate
2001-03-27
2003-07-08
Dickson, Paul N. (Department: 3616)
Land vehicles
Wheeled
Running gear
C280S124155, C267S220000
Reexamination Certificate
active
06588780
ABSTRACT:
INCORPORATION BY REFERENCE
The disclosure of Japanese Patent Application No. 2000-090178 filed on Mar. 29, 2000 including the specification, drawings and abstract is incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to an upper support used in a vehicle suspension system for supporting a piston rod of a shock absorber to a body of the vehicle, in a vibration-damping manner, and more particularly, to an upper support which is usable in a so-called “input separation type” suspension system, wherein the upper support elastically support the piston rod of the shock absorber to the body of the vehicle, independently of a suspension spring of the suspension system.
2. Description of the Related Art
A wheel suspension assembly for an automotive vehicle includes a suspension spring and a shock absorber. The suspension assembly is interposed between a suspension arm or other members connected to a wheel of the vehicle and a body of the vehicle, for pivotally supporting the suspension arm to the vehicle body in a vibration-damping manner. In general, the shock absorber is secured at one end of its piston rod to a part of the vehicle body via a suspension upper support, for reducing or attenuating vibrations transmitted through the shock absorber into the vehicle body.
A known example of the above type of upper support is disclosed in Japanese Patent Laid-Open Publication No. JP-A-11-94007. The disclosed upper support includes: an inner member made of metal; an outer sleeve made of metal and disposed outwardly of the inner member in a radial direction perpendicular to an axial direction of the inner member with a predetermined spacing therebetween; and an rubber elastic body interposed between the inner member and the outer sleeve for elastically connecting therebetween. The outer sleeve has an upper and a lower stopper portions formed at its axially opposite open end portions, respectively, so as to protrude radially inward direction. The disclosed upper support further includes an upper and a lower elastic protrusions which protrude axially outwardly from the inner member in opposite axial directions so that the upper and lower elastic protrusions are held in abutting contact with the upper and lower stopper portions of the outer sleeve, respectively. The upper support constructed as described above is fixed at its inner member to the piston rod of the shock absorber, and is fixed at its outer sleeve to the vehicle body, for thereby elastically supporting the piston rod of the shock absorber with respect to the vehicle body.
However, the disclosed upper support with such conventional structure has a problem that it is likely to generate unusual sound or noise due to sliding or abutting contacts of the rubber elastic body with the outer sleeve member, upon application of high vibrational loads to the upper support in the axial, radial, inclined, torsional and other directions.
As a method to cope with the problem, it has been proposed in the above-indicated publication a modified structure of the upper support in which the rubber elastic body is bonded at its outer surface to the outer sleeve. However, this upper support with the modified structure requires a specific manufacturing step, e.g., an application of the adhesives to the outer sleeve, upon manufacturing thereof, thereby lowering the production efficiency of the upper support, and thereby increasing the cost of manufacture of the upper support. Further, the upper support with the modified structure may possible suffer from deterioration in its noise control effect, due to possible variations in bonding strength between the rubber elastic body and the outer sleeve. The variations of the bonding strength may cause partial debonding or separation of the rubber elastic body from the outer sleeve, upon application of an excessively large load to the upper support, or due to the aging of the upper support.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide an upper support for a vehicle suspension system, which is preferably applicable to an input-separation type suspension system, and which has a novel and simple structure for eliminating or reducing noises generated upon application of a load thereto.
The above and other objects of this invention may be attained according to the following modes of the invention. Each of these modes of the invention is numbered like the appended claims and depends from the other mode or modes, where appropriate, to indicate possible combinations of elements or technical features of the invention. It is to be understood that the principle of the invention is not limited to those modes of the invention and combinations of the technical features, but may otherwise be recognized based on the thought of the present invention that disclosed in the whole specification and drawings or that may be recognized by those skilled in the art in the light of the disclosure in the whole specification and drawings.
(1) An upper support for a suspension system, which is interposed between a body of a vehicle and a shock absorber of the vehicle for elastically supporting the shock absorber with respect to the body independently of a suspension spring of the suspension system, the upper support including: (a) an inner member connectable to a piston rod of the shock absorber; (b) an outer sleeve member which is disposed outwardly of the inner member in a radial direction perpendicular to an axial direction of the inner member with a spacing therebetween, and which is connectable to the body of the vehicle, the outer sleeve member having a first and a second stop portion formed at respective axially opposite open end portions thereof so as to protrude radially inwardly; (c) an elastic body interposed between an outer circumferential surface of the inner member and an inner circumferential surface of the outer sleeve member which is opposed to the outer circumferential surface of the inner member in the radial direction, the elastic body being secured at an inner circumferential surface thereof to the outer circumferential surface of the inner member, while being closely contact at an outer circumferential surface thereof with the inner circumferential surface of the outer sleeve member, the elastic body being held in abutting contact at axially opposite end faces thereof with the first and second stop portions of the outer sleeve member, respectively; and (d) a first and a second elastic protrusion protruding outwardly from the inner member in opposite axial directions, the first and second elastic protrusions being brought into abutting contact with the first and second stop portions of the outer sleeve member, respectively. The elastic body is compressed by the outer sleeve member in the radial direction so that the elastic body exhibits a shear strain of not greater than 1, upon application of an axial load of 1000N between the inner member and the outer sleeve member in a primary load receiving direction.
In the upper support constructed according to the present invention, the elastic body is subjected to a preload in the radial direction, namely the elastic body is previously compressed in the radial direction by a radial compression force having a value not smaller than a predetermined level. This arrangement makes it possible to decrease or minimize an amount of strain or deformation of the elastic body upon application of loads to the upper support. This arrangement also permits an increase of a frictional resistance at an interface formed between the outer circumferential surface of the elastic body and the inner circumferential surface of the outer sleeve, thereby preventing or minimizing a relative displacement between the elastic body and the outer sleeve at the interface. Therefore, the upper support of this invention is capable of minimizing uncomfortable sounds or noises caused by the relative displacement of the elastic body and the outer sleeve at the interface, upon applicat
Hayashi Yukio
Kobayashi Kohichi
Dickson Paul N.
Rosenberg Laura B.
Rossi & Associates
Tokai Rubber Industries Ltd.
LandOfFree
Upper support in vehicle suspension systems does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Upper support in vehicle suspension systems, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Upper support in vehicle suspension systems will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3051097