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. 21, 1989
Filed:
Aug. 20, 1987
Robert L Leon, Roslyn, PA (US);
Liberty Technology Center, Inc., Conshohocken, PA (US);
Abstract
A device for measuring and indicating the forces on a valve stem over at least a portion of the valve strokes is comprised of a strain sensor secured to the valve yoke for sensing strains experienced by the valve yoke. The sensed strains are proportional to the forces on the valve yoke and are equal but opposite to the forces on the valve stem. The strain sensor generates electrical signals proportional to the forces on the valve stem. A display, electrically connected to the strain sensor, is provided for receiving the generated electrical signals and for indicating the forces on the valve stem. A system for evaluating the performance of a valve and valve operator also utilizes the yoke strain sensor in combination with other sensors, including a valve stem motion sensor, a spring pack motion sensor, a motor current sensor and, possibly, a stem strain sensor, as well as an indicator of the condition of torque and limit switches.