Spring devices – Resilient shock or vibration absorber – Including energy absorbing means or feature
Reexamination Certificate
1999-08-02
2001-06-26
Oberleitner, Robert J (Department: 3613)
Spring devices
Resilient shock or vibration absorber
Including energy absorbing means or feature
C267S219000
Reexamination Certificate
active
06250615
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to a vibration isolating device for use in vehicle power train mounting systems and more particularly to a rubber vibration isolating apparatus which limits the axial travel of the device and provides a heat shield.
DESCRIPTION OF THE PRIOR ART
Many isolating devices permit unrestrained axial or longitudinal travel of the damping device, either in tension and/or in compression. Normally, axial or longitudinal travel in the compression mode does not seriously affect the life of the device. However, stretching or axial tension in the rubber device can cause elongation of the rubber and ultimately failure of the rubber component.
This is especially important in hydraulic isolation or damping devices which have a pair of supporting members which are secured to a vibrating body in a frame. A rubber block is disposed between supporting members and the concave surface of the rubber block and a rubber diaphragm which is joined to the rubber block, together define a liquid chamber filled with a damping fluid, such as glycol or a similar fluid. A partition defines the liquid chamber which is divided into a main liquid chamber and an auxiliary liquid chamber. The partition has an opening which is closed with an elastic rubber wall. The partition is also provided with a throttle passageway which communicates with both the main liquid chamber and the auxiliary liquid chamber.
High frequency, low amplitude vibration is imparted into the main liquid chamber which absorbs most of the vibration. Low frequency, high damping forces cause the liquid in the main chamber to move into the auxiliary liquid chamber and thereby absorb the large amplitudes and axial forces. In the process, particularly in the low vibration, high damping modes, the rubber block may be subjected to large axial or longitudinal travel which imposes high compression and alternatively high tension forces in the rubber block. These high tension forces in the rubber block can lead to its premature failure.
Several devices have been proposed to solve this problem, such as U.S. Pat. No. 4,842,258, U.S. Pat. No. 5,178,374, and U.S. Pat. No. 5,501,433. All of these devices seek to limit both the axial stretching mode and the axial compression mode in the rubber block. However, all of these devices are complicated and costly to make.
Thus, none of these devices provides a vibration device that limits axial stretching of the rubber mount, and at the same time provides a heat shield to protect the rubber block from temperature extremes and is simple, compact and inexpensive to make.
SUMMARY OF THE INVENTION
The present invention therefore sets out to solve the problems thus posed above by eliminating these drawbacks. To this end, a vibration damping device in accordance with the present invention is characterized by a pair of support members, one of the support members having a stop. A vibration isolation member is connected to the pair of support members. The vibration isolation member has a rubber block which defines an axis. The block stretches along the axis. A restraint member is connected to the rubber block. The restraint member has a first portion extending along the axis and a second portion attached to the front portion. The second portion engages the stop member to limit the axial travel of the rubber block away from the other of the pair of support assemblies. Additionally, the restraint member forms a heat shield to protect the rubber block.
It is an object of the present invention to provide a damping device with a resilient member where the stretch of elastic rubber block is limited, thus improving useful life for the damping device, is simple, easy to make and does not contribute to the critical core mass.
It is another object of the present invention to provide a damping device with an elastic rubber block which has an axial stretch restraint which also acts as a heat shield to prevent deterioration of the rubber due to temperature.
It is another object of the present invention to attach the stop to one of the support members so that the stop does not contribute to the critical core mass and thus does not deteriorate the resonance performance of the mount.
It is still another object of the present invention to provide a mount which locates the stop so as not to extend below the restraint member but yet permits unrestrained travel of the core toward the chassis side of the mount during its compressive mode and this provides a compact mount device.
It is a further object of the present invention to provide a tension restraint which is attached to one of the support members so as not to cause unwanted resonant effects in the working fluid chamber.
These and other features of the present invention will become apparent upon consideration of the following description and the appended claims with reference to the accompanying drawings all of which form part of the specification.
REFERENCES:
patent: 4621795 (1986-11-01), Eberhard et al.
patent: 4657219 (1987-04-01), Kakimoto
patent: 4669711 (1987-06-01), Beer
patent: 4741520 (1988-05-01), Bellamy et al.
patent: 5009402 (1991-04-01), Sato
patent: 5060919 (1991-10-01), Takano et al.
patent: 5143358 (1992-09-01), Hibi et al.
patent: 5630573 (1997-05-01), Suzuki et al.
patent: 5971376 (1999-10-01), Mori et al.
patent: 6073918 (2000-06-01), Kojima et al.
patent: 0367328 (1993-06-01), None
Continental Automotive Systems, Sound and Vibration Control Brochure, p. 10, Hydrolager (Hydromount).
Freudenberg-NOK General Partnership
Kiczek Casimir R.
Kramer Devon
Oberleitner Robert J
Tucker A. Michael
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