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:
Feb. 19, 2013
Filed:
Mar. 19, 2008
Hideo Ogawa, Minato-ku, JP;
Hideo Ogawa, Minato-ku, JP;
Eagle Industry Co., Ltd., Tokyo, JP;
Abstract
Provided is a solenoid valve wherein control characteristics are prevented from deteriorating due to changes of magnetic characteristics of a magnetic circuit when a center post is contaminated, and the desired control characteristics are maintained for a long period of time. In the solenoid valve, a nonmagnetic layer () is formed on the surface of a center post () by electroless nickel-phosphorous plating or composite electroless nickel-phosphorous plating containing PTFE. Thus, contamination of the center post () is remarkably suppressed, the characteristics of the magnetic circuit for moving the plunger () by magnetic attraction are prevented from changing due to changes of magnetic permeability between the plunger () and the center post (), the plunger () and a valve element () integrated with the plunger are suitably moved corresponding to a current applied to a coil (), and the valve is opened/closed.