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:
Aug. 07, 1990
Filed:
Apr. 12, 1989
Dale A Knutson, Nashotah, WI (US);
Applied Power, Inc., Milwaukee, WI (US);
Abstract
A valve has a magnetic drive unit axially spaced from a valve section. An axially movable armature is moved by an electromagnet and an annular permanent magnet having radial magnetization. Reciprocation of the armature opens and closes a poppet valve to regulate fluid flow between two chambers. The magnetic characteristics of the magnetic drive unit are such that the armature remains in either of two axial limit positions when current is not being applied to the electromagnetic coils. In order to compensate for fluid flow forces tending to close the poppet when open, a biasing spring is also used to help overcome these forces. In an embodiment applied to vehicle shock absorbers, an orifice plate and disc springs are used adjacent the poppet structure to permit damping characteristics which vary depending on whether the piston or the shock absorber is compressing or rebounding.