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:
Mar. 21, 1989
Filed:
Jul. 15, 1987
Dieter Otto, Ennepetal, DE;
Siegfried Hertell, Radevormwald, DE;
Barmag AG, Remscheid, DE;
Abstract
A hydraulic gear pump is disclosed wherein the meshing teeth of the gears define fluid cells which are expanded in the intake portion and receive the fluid from an inlet, and then compressed in the discharge portion to expel the fluid. The contact ratio of the cooperating driving flanks of the meshing teeth is smaller than the contact ratio of the cooperating sealing flanks of the meshing teeth, which serves to minimize the power requirement of the pump. The inlet to the pump includes at least two parallel lines which are each connected to a tank, and the first line is provided with a fixed throttle and the second line is provided with a pressure control valve which is controlled by the pressure in the pump discharge line.