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:
Oct. 28, 2025
Filed:
May. 02, 2023
Regents of the University of Minnesota, Minneapolis, MN (US);
Thomas Richard Chase, Minneapolis, MN (US);
Perry Yan-Ho Li, Plymouth, MN (US);
Michael B. Rannow, Eden Prairie, MN (US);
REGENTS OF THE UNIVERSITY OF MINNESOTA, Minneapolis, MN (US);
Abstract
A partial stroke pump or motor includes a piston coupled to a rotating shaft to evacuate a fluid within a cylinder during an upstroke. A latching check valve includes an actuator piston that is displaceable within a center cavity to bypass a blocking member in a bypass state. The actuator piston is driven by a latch supply line. A spool of a rotary valve selectively couples one of the low and pilot pressure supplies to the latch supply line over different timing angle ranges of the rotating shaft. Coupling of the pilot pressure to the latch supply line causes the bypass state. When operating as a pump, the bypass state causes the pressure in the cylinder to fall below the high pressure during part of the upstroke. When operating as a motor, the bypass state allows the fluid to be evacuated from the cylinder during the upstroke.