Electronic vacuum gauge and systems and methods of calibration and operation of same

摘要

An electronic thermistor-based vacuum gauge and systems and methods of calibration and operation of the same that require no calibration against a known vacuum standard to obtain high accuracy through broad vacuum and ambient temperature ranges. Additional features of the invention include a construction and method of improving battery life, a construction and method of detecting faulty vacuum sensors, a method for determining the state of calibration of a vacuum sensor, a method of quantifying vacuum leak rates, and a method of automatically alerting an operator when an evacuation process has concluded.

主权项

1. A method for detecting a vacuum leak rate of a vacuum system, which comprises:
providing a vacuum-measuring system with:
a vacuum sensor assembly shaped to sealingly contain a volume of gas of the vacuum system and operable to output at least one electrical signal related to the gas vacuum pressure of the contained volume of gas; andan electrical circuit having:
a microprocessor programmed to compute a gas pressure of the volume of gas contained within the vacuum sensor assembly;an analog-to-digital converter operatively connected to the microprocessor and receiving and converting the at least one electrical signal output of the vacuum sensor assembly into a digital signal to be processed by the microprocessor; andan output device operatively connected to the microprocessor and operable to indicate an output of the microprocessor, the output device being at least one of:
an audible alarm operable to indicate when the rate-of-change of the gas pressure exceeds a pre-determined rate; ora display visibly indicating at least one of: the rate-of-change of the gas pressure; or when the rate-of-change of the gas pressure exceeds a pre-determined rate; containing a volume of gas of the vacuum system in the vacuum sensor assembly; computing a gas pressure of the contained volume of gas using the vacuum-measuring system; computing a rate-of-change of the gas pressure with the vacuum-measuring system one of periodically and continuously over a period of time; and outputting the rate-of-change of the gas pressure using the output device.