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:
Dec. 12, 1995
Filed:
Aug. 19, 1994
Robert L Leon, Maple Glen, PA (US);
Liberty Technologies, Inc., Conshohocken, PA (US);
Abstract
A method is disclosed for determining operability of a motor operated valve combination including a valve having a valve stem, a valve disc, a valve seat, and a motor operator having a motor drive interconnecting the motor to the valve stem for movement of the valve disc toward and into engagement with the valve seat to close the valve and a control switch for deactivating the motor. The method comprises the steps of sensing the real motor power of the motor as a function of time during valve closing with zero differential pressure applied to the valve at a first time. From the sensed information, the rate of motor power build-up is determined after the onset of valve wedging during valve closing at the first time. The real motor power of the motor is again sensed as a function of time during valve closing with zero differential pressure applied to the valve at a second time which is subsequent to the first time. The rate of motor power build-up after the onset of valve wedging during valve closing at the second time is determined from the sensed information. The rate of motor power build-up after the onset of valve wedging at the first and second times is compared as an indication of lubrication change within the valve between the first and second times.