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:
Apr. 06, 1982
Filed:
Feb. 28, 1980
Christian B Hansen, Nordborg, DK;
Danfoss A/S, Nordborg, DK;
Abstract
The invention relates to a hydraulic planetary piston type machine and particularly to the rotary slide valve thereof. This type of machine has a rotary piston gear having rotational and orbital movement and a cardan type shaft connects the slide valve to the piston gear. The valve has inlet and outlet, annularly shaped, axially spaced distributor grooves in axially spaced relation. Alternately arranged inlet and outlet stub grooves extend axially from the distributor grooves into axially overlapping relation. The stub grooves in the valve have a commuting action with circumferentially arranged ports in the casing to provide for feeding and exhausting pressurized fluid to and from expanding and contracting chambers formed by the piston gear. In smaller machines the correspondingly smaller flow passages present sufficient flow resistance to substantially affect the efficiency of the machine. In the machine disclosed herein the stub grooves are provided with oblique or curved sections so that the resistance to fluid flow between the distributor grooves and the stub passages is reduced and the efficiency of the machine is thereby substantially increased.