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:
Apr. 22, 1980
Filed:
Jun. 09, 1978
Hideo Wada, Fujisawa, JP;
Izuru Morita, Sagamihara, JP;
Caterpillar Mitsubishi Ltd., Tokyo, JP;
Abstract
A relief and make-up valve assembly is connected to first and second fluid pressure passages in a fluid pressure device. The valve assembly includes a housing of a hollow cylindrical form which communicates with the passages, a valve axially movable in the housing, a piston partitioning the interior of the housing into a low pressure chamber and a back pressure chamber, and a plunger biased by the piston against the valve to move the valve to an opened position away from a valve seat. The valve assembly controls the level of pressure in the first pressure passage by unseating the valve to relieve a preselected pressure from the first pressure passage or alternately to build up a pressure therein.