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:
Jan. 14, 1997
Filed:
Feb. 10, 1995
Bernd Niethammer, Nurtingen, DE;
Hydraulik-Ring Antriebs- und Steuerungstechnik GmbH, Nurtingen, DE;
Abstract
An electroproportional solenoid valve unit has a valve housing with hydraulic connectors for a hydraulic medium. A piston with a hollow interior is positioned in the valve housing and is slidable therein. A pressure spring is arranged at one end of the piston. A solenoid is connected to the valve housing and cooperates with the other end of the piston for moving the piston counter to the force of the spring. A first hydraulic chamber is located at the first end of the piston and a second hydraulic piston is located at the second end of the piston. The piston has a first annular channel adjacent to the first hydraulic chamber and a second annular channel adjacent to the second hydraulic chamber. The first and second annular channels are connectable to the hydraulic connectors. The second hydraulic chamber facing the solenoid is separated from the hollow interior of the piston and from the second annular channel. The first annular channel is connected to the hollow interior of the piston with at least one opening.