| 摘要 |
1,123,887. Refrigerating. TRANE CO. 2 May, 1967 [13 May, 1966], No. 20193/67. Heading F4H. In a vapour-compression refrigeration system having a low-pressure cut-out switch 36 for the compressor, the liquid receiver 16 is located above the evaporator 20 on a support 28 and starting of the compressor under conditions of low ambient temperature, when the condenser pressure is lower than that of the evaporator, is achieved by temporarily interrupting communication between the condenser 14 and receiver and equalizing the pressures in the evaporator and receiver via a line 42 so that liquid refrigerant flows to the evaporator by gravity. The refrigerant evaporates and raises the suction line pressure sufficiently to cause switch 36 to start the compressor. As shown, a three-way valve 44 is employed both to interrupt condenser-receiver communication and to open line 42. The system also includes a valve 40 controlled by a load-responsive switch 30 on the evaporator, a valve 48 which is located in a line 46 by-passing the expansion valve 18 and is opened when line 42 is opened, and a valve 34 which maintains condenser head pressure by controlling refrigerant flow through the condenser and a condenser by-pass line 32. An electric control circuit for the system is described (Fig. 3, not shown). In a modification (Fig. 4, not shown) the functions of valve 44 are performed by valve 34 in combination with check valves in lines 32 and 42. |
