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:
Feb. 19, 1991
Filed:
Nov. 22, 1989
Manfred Grundei, Niederwerrn, DE;
Hans Reimer, Waigolshausen, DE;
Fichtel & Sachs AG, Schweinfurt, DE;
Abstract
According to an illustrative example of this invention, the piston of a hydraulic oscillation damper is provided with a traction valve, i.e. a valve which is intended to damp the outward movement of the piston rod. This traction valve includes two valve discs and a valve member. The valve member is biased towards a closed position and urges the valve discs against a valve face of the piston. In response to a predetermined pressure difference between the two working chambers on both sides of the piston, a flow passage is opened by lifting the valve discs and the valve member from the valve face. Below said predetermined pressure difference, a preliminary restricted flow passage exists. This preliminary restricted flow passage extends in series across the radially inner circumferential edge of a first valve disc adjacent to the piston and through radially inner edge recesses and through radially outer edge recesses of a second valve disc adjacent to the first valve disc. A first liquid flow resistance is established by the radially inner edge recesses, and a second liquid flow resistance is established by the radially outer edge recesses. The first liquid flow resistance is larger than the second flow resistance. Between respective radially inner edge recesses and respective radially outer edge recesses of the second valve disc, circumferential flow paths are established by a circumferential groove within the valve member. These circumferential flow paths act as tranquillizing paths.