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:
Feb. 28, 1989
Filed:
Oct. 20, 1987
Peter Wusthof, Lohr am Main, DE;
Sinclair Cunningham, Fife, GB;
Mannesmann Rexroth GmbH, , DE;
Abstract
The invention relates to a piston machine comprising a plurality of pistons and changeable piston displacement for varying the torque and speed. The pistons are connected via control bores and distributor passages in the distributor of the machine to a high pressure and low pressure connection. To reduce the displacement a switching valve is provided via which the inactive pistons are connected together via their distributor passages and also possibly subjected to an external very low servo pressure or tank pressure. This reduces the frictional losses, increases the efficiency and avoids flow losses of the valve.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile