GB420501A - Improvements in or relating to rotary compressors - Google Patents

Abstract

420,501. Rotary compressors. SULZER FRERES SOC. ANON., Winterthur, Switzerland. Aug. 21, 1934, No. 24076. Convention date, Sept. 29, 1933. [Class 110 (ii)] In a rotary compressor having an eccentric rotor and sliding, or hinged, vanes, the amount of compressed fluid delivered to a port 2 is controlled by opening one or more valves 12, 13, 14, and allowing some of the fluid to flow back to the suction side S before being compressed. Compressed fluid is delivered through orifices 20-23 by way of non-return valves and through a port 24. The zones containing the ports 12-14, and delivery orifices 20-23, may overlap and be separated by a central wall parallel to the casing side walls. The valves 17-19 may be operated manually or automatically in accordance with the fluid pressure or temperature in the suction or delivery pipe. In a refrigerating plant, embodying the invention, an evaporator 30 and a condenser 31 are connected to suction and discharge pipes 1, 2 respectively of a compressor 3. A pressure-reducing valve 33 is fitted in the return pipe 32. Servomotors 42 control the valves 17-19, and are connected to a control device 43. A temperatureresponsive device 45 in the delivery pipe 40 of the evaporator actuates the control 43. Pressure control may replace temperature control in the plant. The valves may be controlled in accordance with the temperature of the cooling liquid of the condenser, or the difference of two temperatures may be employed for controlling the valves.