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:
Jan. 10, 1978
Filed:
Jun. 02, 1976
Theodore Emil Kwast, Anaheim, CA (US);
The Singer Company, New York, NY (US);
Abstract
A slam-shut valve or overpressure shutoff device used in series with, and upstream of, a pressure regulator to provide overpressure protection for apparatus downstream of the pressure regulator in the event of regulator failure. Overpressure or failure of the regulator automatically triggers operation of the slam-shut valve to close the same and prevent further passage of the gas through the pipeline. The slam-shut valve is normally in the open position, and the invention provides for manually resetting the slam-shut valve to reset it in the open position once it has been triggered closed. The valve element is carried on a lever which is pivotally mounted on a reset shaft and spring-biased to close, but prevented from closing by the latch which releasably holds the lever in the open position. The reset shaft is turnable from an external fitting, but will not function until the shaft has been depressed to lock a bolt head in the correspondingly-shaped socket of the lever, whereby on rotation of the shaft, the lever will be raised to re-engage the latch and once again hold the slam-shut valve in the open position. The reset assembly is used subsequent to the overpressure condition being corrected. A further safeguard is embodied in the reset assembly by use of an equalizing valve interconnecting the lever and valve element, and being automatically operated to equalize the pressure upon the initial movement of the reset shaft during the resetting operation.