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:
Nov. 19, 1985
Filed:
Apr. 28, 1981
Johann Merz, Bopfingen, DE;
Zahnradfabrik Friedrichshafen, AG., Friedrichshafen, DE;
Abstract
A rotary slide vane pump for steering booster systems has a flow control valve which bypasses flow from outlet side to suction side with increase in speed as heretofore known. The flow channels or passages that conduct bypass flow change the direction of the flow at a juncture point between passages, such directional change being a right angle, radially downstream from the bypass valve to longitudinally at the point of juncture to the suction side, likewise as heretofore known. In the present invention there is provided a transition piece between the channels at the right angle juncture in the form of a screw in the pump body and having a flat face disposed flush with the longitudinal channel and transversely of the radial channel. The provision of such transition piece has been found to effect an increase in suction pressure when bypass flow is added to normal suction flow, such increase being over and above that effected by the prior art. The result is an enhanced suction volume in pump operation, avoidance of cavitation damage due to insufficient intake filling and reduction of noise.