Heat pump air conditioner

Abstract

A heat pump air conditioner includes an intake side heat exchanger including heat transfer pipes passing a refrigerant and being arranged in a direction along an air inlet face, intake heat exchanger configured to cool or warm air and supply the air to a space. A plurality of heat pumps include a plurality of compressors and configured to compress the refrigerant and supply the compressed refrigerant to the heat transfer pipes and a plurality of heat side exchangers and connected to the respective compressors, the heat pumps sharing the air intake side heat exchanger, and a controller configured to switch a state of the compressors and between an operating state and an operation stopped state. The controller controls the compressors and to switch an operation of each of the compressors and between starting and stopping in accordance with a magnitude of an air-conditioning load.

What is claimed is: 
     
         1 . A heat pump air conditioner comprising:
 an air-intake-side heat exchanger including a plurality of heat transfer pipes through which a refrigerant passes, the heat transfer pipes being arranged in a direction along an air inlet face of the air-intake-side heat exchanger, the air-intake-side heat exchanger being configured to convert intake air into cool air or warm air and supply the cool air or warm air to a space to be air conditioned;   a plurality of first and second heat pumps including, at least, a plurality of compressors configured to compress the refrigerant and supply the compressed refrigerant to the heat transfer pipes and a plurality of heat-source-side heat exchangers connected to the respective compressors, the first and second heat pumps sharing the air-intake-side heat exchanger; and   a controller configured to switch a state of the compressors between an operating state and an operation stopped state, wherein   the controller controls the compressors to switch an operation of each of the compressors between starting and stopping in accordance with a magnitude of an air-conditioning load.   
     
     
         2 . The heat pump air conditioner according to  claim 1 , wherein
 among the plurality of heat transfer pipes, a plurality of heat transfer pipes connected to the first heat pump serve as first heat transfer pipes, and a plurality of heat transfer pipes connected to the second heat pump serve as second heat transfer pipes, and   the plurality of first heat transfer pipes and the plurality of second heat transfer pipes are arranged such that, in the one direction, one first heat transfer pipe and one second heat transfer pipe are arranged alternately, or two first heat transfer pipes and two second heat transfer pipes are arranged alternately.   
     
     
         3 . The heat pump air conditioner according to  claim 1 , wherein
 the controller causes at least a pair of the compressors to operate alternately.   
     
     
         4 . The heat pump air conditioner according to  claim 2 , wherein
 the controller causes at least a pair of the compressors to operate alternately.   
     
     
         5 . The heat pump air conditioner according to  claim 3 , wherein
 before causing the pair of the compressors to operate alternately, the controller totals either a previous operating time of each of the compressors or the number of previously performed operations of each of the compressors, and   the controller preferentially causes one of the compressors with a less previous operating time or a less number of previously performed operations to operate.   
     
     
         6 . The heat pump air conditioner according to  claim 4 , wherein
 before causing the pair of the compressors to operate alternately, the controller totals either a previous operating time of each of the compressors or the number of previously performed operations of each of the compressors, and   the controller preferentially causes one of the compressors with a less previous operating time or a less number of previously performed operations to operate.   
     
     
         7 . The heat pump air conditioner according to  claim 3 , wherein
 the controller switches a state of the pair of the compressors between an operating state and an operation stopped state not in a defrosting operation period, but in a period other than the defrosting operation period.   
     
     
         8 . The heat pump air conditioner according to  claim 4 , wherein
 the controller switches a state of the pair of the compressors between an operating state and an operation stopped state not in a defrosting operation period, but in a period other than the defrosting operation period.   
     
     
         9 . The heat pump air conditioner according to  claim 1 , wherein
 after causing the second heat pump to start operating, when causing the first heat pump to start operating, the controller controls the operation of the second heat pump to reduce an output of the second heat pump, such that an output of the first heat pump when the first heat pump starts operating is subtracted from the output of the second heat pump, which has already started operating.   
     
     
         10 . The heat pump air conditioner according to  claim 2 , wherein
 after causing the second heat pump to start operating, when causing the first heat pump to start operating, the controller controls the operation of the second heat pump to reduce an output of the second heat pump, such that an output of the first heat pump when the first heat pump starts operating is subtracted from the output of the second heat pump, which has already started operating.   
     
     
         11 . The heat pump air conditioner according to  claim 1 , wherein
 the controller performs a stop operation of causing the first heat pump to operate such that an output of the first heat pump decreases in accordance with elapse of time, and then causing the second heat pump to operate such that an output of the second heat pump decreases in accordance with elapse of time, and   in the stop operation, the controller controls the operation of the second heat pump such that, when the first heat pump stops operating, the output of the second heat pump increases by an amount corresponding to a decrease in the output of the first heat pump, the decrease occurring immediately before the first heat pump stops operating.   
     
     
         12 . The heat pump air conditioner according to  claim 2 , wherein
 the controller performs a stop operation of causing the first heat pump to operate such that an output of the first heat pump decreases in accordance with elapse of time, and then causing the second heat pump to operate such that an output of the second heat pump decreases in accordance with elapse of time, and   in the stop operation, the controller controls the operation of the second heat pump such that, when the first heat pump stops operating, the output of the second heat pump increases by an amount corresponding to a decrease in the output of the first heat pump, the decrease occurring immediately before the first heat pump stops operating.   
     
     
         13 . The heat pump air conditioner according to  claim 1 , wherein the plurality of first and second heat pumps have different minimum critical powers from each other. 
     
     
         14 . The heat pump air conditioner according to  claim 2 , wherein the plurality of first and second heat pumps have different minimum critical powers from each other. 
     
     
         15 . The heat pump air conditioner according to  claim 1 , further comprising a vaporizing humidifier and a steam humidifier, wherein
 along an air passage, the vaporizing humidifier is disposed downstream of the air-intake-side heat exchanger, and the steam humidifier is disposed downstream of the vaporizing humidifier,   the vaporizing humidifier and the steam humidifier are connected to the controller, and   the controller causes the vaporizing humidifier to humidify intake air, and then if the humidifying of the intake air by the vaporizing humidifier is insufficient, causes the steam humidifier to operate to further humidify the intake air.   
     
     
         16 . The heat pump air conditioner according to  claim 2 , further comprising a vaporizing humidifier and a steam humidifier, wherein
 along an air passage, the vaporizing humidifier is disposed downstream of the air-intake-side heat exchanger, and the steam humidifier is disposed downstream of the vaporizing humidifier,   the vaporizing humidifier and the steam humidifier are connected to the controller, and   the controller causes the vaporizing humidifier to humidify intake air, and then if the humidifying of the intake air by the vaporizing humidifier is insufficient, causes the steam humidifier to operate to further humidify the intake air.   
     
     
         17 . The heat pump air conditioner according to  claim 1 , wherein
 a cross section of each heat transfer pipe has an ellipsoidal shape.   
     
     
         18 . The heat pump air conditioner according to  claim 2 , wherein
 a cross section of each heat transfer pipe has an ellipsoidal shape.