Design and Development of a Servocontrolled Gas Inbleed System for a High Vacuum Calibration Chamber

摘要

A servocontrolled gas inbleed system for a dynamic, calibrated conductance type of vacuum calibration system was designed and fabricated. The servocontrolled gas inbleed system automatically regulates the flow of gas into the test region of the calibration system by maintaining a constant pressure on the upstream side of a molecular leak. Constant pressure on the molecular leak is established and maintained by a shunt control technique in which a gas inlet valve and a gas pumpout valve are operated in parallel. An analog computer was used to aid in the design of the system. The transient and steady-state response of the servocontrolled gas inbleed system is predicted by the computer. Good agreement was obtained between the analog computer data and the experimental performance data obtained from the gas inbleed system. The gas inbleed system can control the flow rate in the range from 0.00001 torr-liters/sec to 0.001 torr-liters/sec. Other flow rates are obtainable by changing system components; however, the same design procedure is applicable. (Author)