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. 27, 1994
Filed:
Mar. 12, 1993
Raymond J Andrejasich, Carmel, IN (US);
Roy E Kidd, Clayton, IN (US);
Emerson Electric Co., St. Louis, MO (US);
Abstract
A microprocessor controlled timer is installed in a petroleum service station product dispensing system that includes a pump relay, a pump, a dispenser, and a leak detection monitor. The timer activates pump relays to pressurize a liquid product line that runs from a tank to the dispenser at predetermined intervals to compensate for thermal contraction during product line leakage testing. Prior to activating pump relays, the timer has circuitry to determines if product is currently being dispensed. If product is being dispensed, the timer waits until dispensing has halted before activating pump relays to pressurize the product line. Also prior to activating pump relays, the timer has circuitry to determine if pump operation should be inhibited and if so halts before activating pump relays. Optical isolation is used between the timer and pump relays and a dispenser switch.