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:
Jun. 30, 1981
Filed:
Jun. 13, 1979
Jan Zangenberg, Nordborg, DK;
Peter J Clausen, Nordborg, DK;
Danfoss A/S, Nordborg, DK;
Abstract
The invention relates to a control unit for an adjustable fluid pump or motor controlled by a servomotor. The control unit is of the type having a slide valve with a neutral blocking position with supply and exhaust positions on opposite sides of the neutral position. The neutral position provides a zero pump feed condition and the improvement resides in a construction wherein the fed amount is absolutely zero. This is accomplished with a secondary valve which has a fixed part and a moveable part which moves with the actuator. The secondary valve has fluid passages which short circuit the supply and exhaust connections of the unit over a small travel range on opposite sides of the neutral position of the actuator.