METHOD FOR SETTING PRESSURE IN CONTROLLED VOLUME, AND UNIT FOR ITS IMPLEMENTATION Russian patent published in 2013 - IPC G01L27/00 

FIELD: machine building.

SUBSTANCE: method for setting pressure in controlled volume consists in the fact that a roughly set pressure value in the controlled volume is specified. Pressure is measured in it from time to time, and when its value deviates from the specified one, amount of compressed gas is calculated, which is necessary to introduce to the controlled volume or to remove from it. Required amount of gas is supplied or removed, which is then accurately maintained to provide its content in the controlled volume. Accurate control of the pressure value in the controlled volume is performed by changing the resistance of a pipeline in a control scheme at setting of excess pressure from minimum value to maximum value, thus stopping gas supply, with further maintenance of the specified pressure in the controlled volume by short-time opening of an inlet valve for gas supply or an outlet valve for gas discharge from the working capacity. At setting of negative pressure - from minimum resistance and to maximum resistance value by switching off all the valves of flow control elements and then the outlet valve, thus stopping gas discharge from the working capacity. Further maintenance of the specified negative pressure in the controlled volume with required discreteness is performed by short-time opening of the inlet valve for gas supply or the outlet valve for gas discharge from the working capacity. The unit for setting pressure in the controlled volume includes high and low pressure sources and an inlet group of inlet and outlet valves with the control scheme. The latter includes the inlet group of valves, pipelines for gas passage and flow control elements connected to each other, as well as the working capacity. Inlet group of valves consists of parallel connected inlet and outlet valves connected at one point to the first of n flow control elements. Pressure sources are connected to inlet valves through protection filters of the control system against probable contaminations.

EFFECT: simplifying pressure setting devices-at maintaining high control stability and low flow of working medium.

2 cl, 1 dwg