Patent ID: 7775059

Claim:
An air conditioner comprising a fixed displacement-type first compression mechanism and a variable displacement-type second compression mechanism independent from each other in a refrigeration cycle, and further comprising second compression mechanism displacement control means for controlling a displacement of said second compression mechanism, compression mechanism operation switching control means for switching to an operation by said two compression mechanisms or a sole operation by any one compression mechanism, an evaporator for refrigerant for cooling air for air conditioning, a condenser for refrigerant, a blower for sending air to said evaporator, evaporator temperature detection means for detecting a temperature of said evaporator or a temperature of air at an exit of said evaporator (Teva), and evaporator target temperature calculation means for calculating a target temperature (Toff) of said evaporator temperature or said evaporator exit air temperature, wherein, when said refrigeration cycle is operated only by said first compression mechanism, a temperature (Teva) detected by said evaporator temperature detection means, a temperature (Toff) calculated by said evaporator target temperature calculation means and a predetermined value A are referred, and if a condition of Teva−Toff≧A is satisfied, said first compression mechanism and said second compression mechanism are operated simultaneously, wherein, when said refrigeration cycle is operated by said first and second compression mechanisms, said Teva, said Toff, a temperature in an objective room for air conditioning (Tin), a room interior target temperature (Tset), a predetermined value F, a predetermined time G, and a predetermined value H are referred, and when any one condition of said condition where a time having satisfied said condition of Teva−Toff≧F is G or more, a condition of Tin−Tset≧H, and a condition where said displacement of said second compression mechanism is a predetermined value I or less, is satisfied, only said first compression mechanism is operated.