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:
Nov. 02, 2004
Filed:
May. 28, 2003
Yuuji Ogura, Imizu-gun, JP;
Satoshi Hamamoto, Nei-gun, JP;
Zenzou Hamada, Uozu, JP;
Satoshi Okude, Nei-gun, JP;
Nachi-Fujikoshi Corp., Toyama, JP;
Abstract
A spool valve comprises a slidable spool, and through displacement of the spool a supply port of the valve is allowed to communicate with one of the load ports of the valve while the other load port is allowed to communicate with a corresponding one of return ports of the valve. The spool is provided with a portion, the outside diameter of which gradually increases, at least on the other load port side from the center of a central concave portion of the spool. The outside diameter gradually increasing portion decreases fluid force which acts against an operating force of the spool when the valve is activated.