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. 03, 1998
Filed:
Jul. 11, 1997
Gordon Yowell, Boca Raton, FL (US);
Stephen Kaylor, Boca Raton, FL (US);
Duane Samuelson, Boca Raton, FL (US);
Alvin S Blum, Fort Lauderdale, FL (US);
Predator Systems Incorporated, Boca Raton, FL (US);
Abstract
A valve assembly senses the cumulative volume of hydraulic fluid that has passed to an actuator and senses and subtracts from that cumulative volume the volume of return fluid that has passed from the actuator. When the difference between the volumes exceeds a preset value, the system shuts off the flow to the actuator to prevent further loss of fluid from a leak. The assembly may employ separate sensors in separate pressure and return lines or a common line with a common sensor which reverses signal polarity when flow reverses. Target flowmeters with signal adding and subtracting circuits may provide the differential volume information.