US 5,333,115 A · Line leak test apparatus responsive to pump use

Abstract

A line leak test probe for use in a liquid storage and dispensing system which includes a pump. A pressure transducer provides a pressure signal to a microprocessor-based test circuit. Various conditions descriptive of the pressure versus time curve while the pump is running, such as the pressure will rise above 20 psi when the pump is turned on, drop when the liquid is dispensed, and rise again when the dispenser is turned off, are stored within a software program in the microprocessor memory. The microprocessor calculates an average pressure to average out noise and artifacts in the pressure, and waits for the pressure to drop 2 psi below the average pressure after the pump has been turned off before performing leak tests in order to give the noise and artifacts time to die down.

Claims11

Dependent claims

A line leak test probe for use in a liquid storage and despensing system which includes a pump for pumping said liquid, said probe comprising:

pressure transducer means for providing an electrical signal representative of the pressure in a liquid conduit;
and
leak test means responsive to said electrical signal for testing said system for leaks and for providing an output signal indicative of leak;
said leak test means including:
storage means for storing one or more predetermined conditions related to whether or not said pump is in use;
and
pump use means communicating with said storage means for determining whether said pump is "off" prior to beginning a leakage test by distinguishing between product line pressure variations caused by despensing said liquid and product line pressure decay caused by a leak through continuous pressure monitoring to create a pressure running average.

4 more elements

Dependencies are inferred from the claim text.

Line leak test apparatus responsive to pump use

Life of this patent

Line leak test apparatus responsive to pump use

Life of this patent

Abstract

Claims11