Encapsulated hermetic refrigerating unit - has compressor in casing under negative pressure with high liq. level control preventing motor starting

摘要

The refrigerating unit has a compressor fitted in a casing kept under negative pressure. The unit is fitted with a device preventing the compressor from starting as long as the casing is filled with liquid refrigerant. The casing (1) contains the compressor (3) driven by asynchronous motor. The compressor sucks refrigerant gas from the casing space (4) and delivers via discharge pipe (5) to the condenser. The refrigerant gas returns to the casing via connection (7). The motor (M) has a starting winding (9) and a running winding (8). In the starting line of the motor is a blocking device (15) fitted consisting of a bi-metal switch which is designed to close only when the temp. within the casing exceeds 50 deg.C, i.e. when the liquid refrigerant accumulated previously has evaporated.