GB181007A - Improvements relating to refrigerating installations with rotary compressors - Google Patents

Abstract

181,007. Akt.-Ges. der Maschinenfabriken Escher, Wyss, et Cie. May 30, 1921, [Convention date]. Automatic gear.- In a refrigerating- plant provided with a rotary compressor driven by a fluidpressure engine or an electric motor, the speed of the engine or motor is made dependent upon the pressure in the liquefier or evaporator, or upon the height of the liquid in the liquefier which liquid may also operate a float device to control a throttle valve leading to the evaporator. The compressor 1 is connected to a liquefier 3, Fig. 1, and an evaporator 8 by means of a pipe 9. A tank 4 and a throttle valve 6 are interposed between the liquefier 3 and the evaporator 8. The pressure in the evaporator operates a spring-pressed piston 11 connected through a floating lever 14 to a valve 16, 17 controlling motors 18, 19 which are operated to rotate wheels 21, 22 to raise or lower the turbine-supply valve 25. A float 33 in the tank 4 similarly adjusts the point 39 of the lever 14 to move the valve 25. The screw 23 carrying the valve 25 is connected to a piston 24 operated by a speed governor 28 through a fluid relay. In modifications, the tank 4 is dispensed with, the liquefier 3 is connected directly to the valve 6, and either the liquefier or evaporator pressure alone is adapted to control the valve 16, 17. The speed of the compressor is increased or decreased when the liquefier or evaporator pressure rises or falls, or the float 33 falls or rises respectively. When the compressor is driven by an electric motor, the above control devices may vary the resistance in the supply current, or adjust the brushes, or otherwise control the motor.