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:
Jul. 19, 1994
Filed:
Sep. 24, 1993
Kazuya Takano, Kamakura, JP;
Hiroshi Kojima, Yokohama, JP;
Bridgestone Corporation, Tokyo, JP;
Abstract
A vibration damping apparatus which is particularly applicable to an automotive engine mount and capable of fully absorbing vibration from vibration generating sources. A sleeve is secured to the automotive engine unit, and a housing is secured to the vehicle body. Once the vibration generated by the automotive engine is transmitted to the sleeve, liquid loaded in a main liquid chamber flows to a sub liquid chamber via a plurality of restricting passages. Vibration is effectively absorbed by the transit resistance against liquid flowing through those restricting passages. Independent of these restricting passages, a cylindrical member is provided which penetrates through the housing and a partition wall block. The cylindrical member is disposed in the path of the restricting passages providing connection between the main and sub liquid chambers. A hollow rotor is rotatably provided, inside of and on the same axial line as the cylindrical member, for opening and closing the restricting passages. When low-frequency vibration is generated, only the restricting passage devoid of the hollow rotor provides connection between the main and sub liquid chambers. Conversely, when high-frequency vibration is generated, those restricting passages each containing the hollow rotor and having a large sectional area are released to provide connection between both chambers thus reliably and effectively absorbing vibrations throughout an extensive range of frequencies.