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. 16, 2002
Filed:
Jul. 21, 2000
Applicant:
Inventors:
Assignee:
Other;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F15B 1/3043 ;
U.S. Cl.
CPC ...
F15B 1/3043 ;
Abstract
A main passage communicated to a pump passage or a tank passage by switching operation of a spool valve is provided with an operation check valve permitting communication only to a cylinder. A puppet in the operation check valve is provided with an orifice communicating the main passage with a pilot chamber of the operation check valve. The pilot chamber is communicated with the main passage through an electromagnetic on/off valve. Further, the pilot chamber in the operation check valve is communicated through a bypass passage with the main passage, and the bypass passage is provided with a manually operable opening/closing valve.