GB642155A - Improvements in or relating to refrigerated vehicles - Google Patents

Abstract

642,155. Refrigerating. STANDARD CAP & SEAL CORPORATION. Oct. 13, 1947, No. 27396. Convention date, May 14, 1946. [Class 291 [Also in Group XXIX] An absorption refrigerating system cooling the storage container 10 of a refrigerated vehicle comprises evaporators 17 located near the ceiling connected by headers 14, 16 and pipes 13, 15 to. tanks 12 which are fed with liquid refrigerant by pipes 19 from tanks 20, 21 and from which vapour flows by pipes 29 to pairs of absorbent holdsrs 30, 31, valves 24 being interposed in the pipes 19 to control the liquid flow in response to the liquid level in the tanks 12. Valve means 36 are interposed in the pipe 29 to control the vapour. flow in response to the temperature in the container 10 and to the pressure in the evaporators 17. Clamped to a nipple 26, communicating with the tank 12 is a bulb 27 connected to a capillary tube 28 the pressure in which influences a diaphragm in the valve 24. The diaphragm; through rods operates a needle valve to control the flow of liquid through the pipe 19, a filter being incorporated within the valve 24. The valve means 36 in the conduit 29 comprise a main control valve 39, Fig. 4, influenced by refrigerant vapour pressure which is communicated through a valve 40 influenced by a thermostat bulb 38 within the chamber. 10. Refrigerant vapour flows through a pipe 75 connected to the pipe 29 to the valve 40 in which it can flow to a pipe 76 between a diaphragm 67, Fig. 7, and seating 65. The diaphragm 67 is actuated by rods 72 moved by a diaphragm 71 which. is itself moved by the pressure existing in a chamber 73 in communication with the thermostatic element 37, 38. Refrigerant vapour can flow from the pipe 76, through a chamber 61 in the valve 39, past the seating 56 of a spring-loaded diaphragm 57 to actuate a piston 46 which operates the members 44, 48 of the main valve 39 in the refrigerant vapour pipe 29. Thus if the temperature rises in the chamber 10, the bulb 38 will operate the valve 40 to admit refrigerant vapour to the pipe 76 but if the refrigerant vapour pressure is low (i.e. the evaporators are at a low temperature) the refrigerant vapour will be unable to force up the diaphragm 57: in the valve 39 and so this valve will remain closed. If, however, the evaporator 17 is itself warm the vapour pressure will be high and will operate the diaphragm 57 and hence open the valve 39 to reduce the vapour pressure in the pipe 29 and so increase the rate of evaporation. In a modification (Fig. 2, not shown) the refrigerant holders. 20, 21 are disposed within the container 10 and only one tank 12 is provided to supply a vertical array of evaporators 17 through the connections 13, 15 and the headers 14, 16. Connections are provided for connecting the holders 20, 21; 30, 31 to a stationary charging plant. Specification 639,271 is referred to.