Patent ID: 6951116
Filing Date: 2005-10-04
Classification: F25B,Y02B

Abstract:
1. An air conditioner comprising: a plurality of compressors for compressing a refrigerant; a condenser for condensing the refrigerant; an electronic expansion valve for expanding the refrigerant; an evaporator for evaporating the refrigerant; a direction changing valve for changing a flow direction of the refrigerant; a refrigerant conduit for connecting the plurality of compressors, the condenser, the electronic expansion valve, the evaporator and the direction changing valve; and a first temperature sensor, installed at inlets of the compressors, for measuring a temperature of the refrigerant drawn into the compressors; a second temperature sensor, installed at the evaporator, for measuring a temperature of the refrigerant passing through the evaporator; a third temperature sensor, installed outdoors, for measuring an outdoor temperature; and a microcomputer for controlling operation of the air conditioner, wherein the microcomputer controls an opening degree of the electronic expansion valve so that a current degree of superheat coincides with a target degree of superheat set according to the refrigerant compression capacity of at least one operating compressor and an outdoor temperature when at least one compressor is operated so that the refrigerant compression capacity is varied in accordance with a one of a cooling load and a heating load, wherein the microcomputer sets a difference between the temperature of the refrigerant at the inlets of the compressors measured by the first temperature sensor and the temperature of the refrigerant at the evaporator measured by the second temperature sensor as a current degree of superheat, and sets the target degree of superheat according to the refrigerant compression capacity of the at least one operating compressor and the outdoor temperature measured by the third temperature sensor.