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. 20, 1990
Filed:
Nov. 16, 1989
Kouji Ichihashi, Saitama, JP;
Jun-ichi Yasuma, Saitama, JP;
Diesel Kiki Co., Ltd., Tokyo, JP;
Abstract
An electromagnetic proportional pressure control valve includes a housing, and a spool slidably received in the housing. The spool has a pair of first and second pressure receiving portions which are equal to each other in effective pressure receiving area. A primary pressure in a primary port is applied to the first pressure receiving portion, and a secondary pressure in a secondary port is applied to the second pressure receiving portion. A form due to the primary pressure acts on the spool in a direction to increase the secondary pressure, and a force due to the secondary pressure acts on the spool in a direction to decrease the secondary pressure. A force of a spring and a force of an electromagnetic actuator also act on the spool in the opposite directions. A variation in the primary pressure directly appears in the secondary pressure.