Analysis of Oil Pumping in the Hermetic Reciprocating Compressor for Household Refrigerators

For a hermetic reciprocating compressor of the household refrigerator, it is not economic to set a separate oil pump, because of cost and space demands. Its oil supply system is mainly promoted by a reed pump and the spiral groove on the shaft. When the compressor is operating, the oil climbs up the inner wall of the reed pump because of the centrifugal force. The height to which the oil could climbs is thus mainly determined by the rotation speed of the shaft. This paper presents a theoretical simulation of the effect of the centrifugal force on the oil flow. Results show that the reed pump will fail, when the rotation speed is below 2000rpm. For a variable speed compressor of the household refrigerator, the design of the reed pump must be optimized or a new design of the oil supply system should be found.