The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 20, 1991
Filed:
Apr. 09, 1990
Susan I Veverka, Elyria, OH (US);
Stephen F Roth, Berlin Heights, OH (US);
The Pullman Company, , US;
Abstract
A vibration damping device of the bushing-type includes a rigid outer housing and a rigid inner member, having a first side and a second side, which is substantially enclosed by the outer housing. A first vibration absorbing resilient body is interposed between the first side of the inner member and the outer housing. The first body is made of an elastomeric material having a first spring rate. A second vibration absorbing resilient body is interposed between the second side of the inner member and the outer housing. The second body is made of an elastomeric material having a second spring rate which is different from the first spring rate such that a deflection of the rigid inner member toward one of the first and second bodies will be resisted more strongly than a deflection of the rigid inner member toward the other of the first and second bodies. A first fluid chamber is defined in the second body and a second fluid chamber is defined between the second body and the outer housing. The second fluid chamber is in fluid communication with the first chamber through a first fluid passageway. A plate is moveably mounted in the first passageway for movement perpendicular to a longitudinal axis of the device. The plate controls a flow of fluid through the first passageway to a varying extent depending upon the position of the plate in the first passageway. A second fluid passageway communicates with the first and second fluid chambers through a circuitous path.