Heat pump type cooling/heating apparatus

Abstract

A heat pump type cooling/heating apparatus comprises a coolant injection path and a gaseous coolant adjustment valve. The coolant injection path may be split between a cascade heat exchanger and an evaporator of a low-temperature refrigeration cycle to inject coolant into a low pressure side compressor, or between a water coolant heat exchanger and cascade heat exchanger to inject coolant into a high pressure side compressor of a high temperature refrigeration cycle. The gaseous coolant adjustment valve may be provided in the coolant injection path and is adjusted to correspond to a load of a

1 . A heat pump type cooling/heating apparatus comprising:
 a cascade cycle unit that includes a cascade heat exchanger that performs a heat exchange between a first coolant of a low temperature refrigeration cycle and a second coolant of a high temperature refrigeration cycle, and   a water coolant heat exchanger that heats water while the second coolant of the high temperature refrigeration cycle is condensed, wherein the water coolant heat exchanger is coupled to a destination via a water circulation path, the heat pump type cooling/heating apparatus further comprising:   a coolant injection path that is split between the cascade heat exchanger and an evaporator of the low temperature refrigeration cycle to inject a coolant into a low pressure side compressor of the low temperature refrigeration cycle, or split between the water coolant heat exchanger and the cascade heat exchanger to inject a coolant into a high pressure side compressor of the high temperature refrigeration cycle; and   a gaseous coolant adjustment valve provided in the coolant injection path and adjusted corresponding to a load of the destination.   
     
     
         2 . The apparatus of  claim 1 , further comprising:
 a gas/liquid separator to separate a coolant condensed in the cascade heat exchanger into a liquid coolant and a gaseous coolant; and   an auxiliary expansion mechanism, provided between the cascade heat exchanger and the gas/liquid separator, to expand a coolant.   
     
     
         3 . The apparatus of  claim 2 , wherein:
 the low temperature refrigeration cycle forms a closed path running from a low pressure side compressor through the cascade heat exchanger and a first expansion mechanism to an evaporator,   the high temperature refrigeration cycle forms a closed path running from a high pressure side compressor through the water coolant heat exchanger and a second expansion mechanism to the cascade heat exchanger, and   the gas/liquid separator is provided between the cascade heat exchanger and the first expansion mechanism.   
     
     
         4 . The apparatus of  claim 3 , wherein the low pressure side compressor, the cascade heat exchanger, the first expansion mechanism, the evaporator, the high pressure side compressor, the second expansion mechanism, the water coolant heat exchanger, the coolant injection path, the gaseous coolant adjustment valve, the gas/liquid separator, and the auxiliary expansion mechanism are installed in a single unit. 
     
     
         5 . The apparatus of  claim 3 , wherein:
 the low pressure compressor, first expansion mechanism, and evaporator are installed in an outdoor unit,   the cascade heat exchanger, high pressure side compressor, second expansion mechanism, and water coolant heat exchanger are installed in a cascade unit, and   the coolant injection path, gaseous coolant adjustment valve, gas/liquid separator, and auxiliary expansion mechanism are installed in one of the outdoor unit or the cascade unit.   
     
     
         6 . The apparatus of  claim 1 , further comprising:
 a gas/liquid separator to separate a coolant condensed in the water coolant heat exchanger into a liquid coolant and a gaseous coolant; and   an auxiliary expansion mechanism, provided between the water coolant heat exchanger and the gas/liquid separator, to expand a coolant.   
     
     
         7 . The apparatus of  claim 6 , wherein:
 the low temperature refrigeration cycle forms a closed path running from a low pressure side compressor through the cascade heat exchanger and a first expansion mechanism to an evaporator,   the high temperature refrigeration cycle forms a closed path running from a high pressure side compressor through the water coolant heat exchanger and a second expansion mechanism to the cascade heat exchanger, and   the gas/liquid separator is provided between the water coolant heat exchanger and the second expansion mechanism.   
     
     
         8 . The apparatus of  claim 7 , wherein:
 the low pressure side compressor, cascade heat exchanger, first expansion mechanism, evaporator, high pressure side compressor, second expansion mechanism, water coolant heat exchanger, coolant injection path, gaseous coolant adjustment valve, gas/liquid separator, and auxiliary expansion mechanism are installed in a single unit.   
     
     
         9 . The apparatus of  claim 7 , wherein:
 the low pressure compressor, first expansion mechanism, and evaporator are installed in an outdoor unit,   the cascade heat exchanger, high pressure side compressor, second expansion mechanism, and water coolant heat exchanger are installed in a cascade unit, and   the coolant injection path, gaseous coolant adjustment valve, gas/liquid separator, and auxiliary expansion mechanism are installed in one of the outdoor unit or the cascade unit.   
     
     
         10 . The apparatus of  claim 9 , wherein the cascade unit is integrally mounted on the outdoor unit. 
     
     
         11 . The apparatus of  claim 9 , wherein the cascade unit is separated from the outdoor unit. 
     
     
         12 . The apparatus of  claim 1 , further comprising:
 a load sensor to sense the load of the destination; and   a controller to control the gaseous coolant adjust valve according to a sensing result of the load sensor.   
     
     
         13 . The apparatus of  claim 12 , wherein the load sensor is provided over the water circulation path. 
     
     
         14 . The apparatus of  claim 13 , wherein the controller opens the gaseous coolant adjustment valve when a temperature sensed by the load sensor is less than a predetermined valve, and closes the gaseous coolant adjustment valve when a temperature sensed by the load sensor is more than the predetermined valve. 
     
     
         15 . The apparatus of  claim 1 , wherein the destination includes a room heating unit coupled to the water circulation path and a water heating unit connected to the water circulation path. 
     
     
         16 . The apparatus of  claim 1 , wherein at least one of the low pressure side compressor or the high pressure compressor, which is coupled to the coolant injection path, is configured as a two-stage compressor. 
     
     
         17 . The apparatus of  claim 1 , wherein at least one of the low pressure side compressor or the high pressure compressor, which is coupled to the coolant injection path, is configured as a screw compressor. 
     
     
         18 . The apparatus of  claim 1 , wherein at least one of the low pressure side compressor or the high pressure compressor, which is coupled to the coolant injection path, is configured as a scroll compressor. 
     
     
         19 . The apparatus of  claim 1 , wherein at least one of the low pressure side compressor or the high pressure compressor, which is coupled to the coolant injection path, is configured as a twin rotary compressor.