Humidity control apparatus

Abstract

A humidity control apparatus includes a refrigerant circuit ( 50 ) which has a compressor ( 53 ), a main electric-operated expansion valve ( 55 ), and a first adsorption heat exchanger ( 51 ) and a second adsorption heat exchanger ( 52 ) on which adsorbent for adsorbing moisture in air is supported, and in which refrigerant reversibly circulates to perform a vapor compression refrigeration cycle. In the humidity control apparatus, refrigerant circulation in the refrigerant circuit ( 50 ) is reversibly switched to alternately perform an adsorption process and a recovery process with the adsorbent in the adsorption heat exchangers ( 51, 52 ), and the humidity of air passing through the adsorption heat exchangers ( 51, 52 ) is adjusted. The refrigerant circuit ( 50 ) is provided on an upstream side of the adsorption heat exchanger ( 51, 52 ) in a recovery air flow, and includes an auxiliary heat exchanger ( 61 ) configured to preheat recovery air to be supplied to the adsorption heat exchanger ( 51, 52 ), and a refrigerant adjusting mechanism ( 62 ) configured to adjust an amount of refrigerant flowing into the auxiliary heat exchanger ( 61 ).

1 . A humidity control apparatus which includes a refrigerant circuit ( 50 ) having a compressor ( 53 ), a main expansion mechanism ( 55 ), and a first adsorption heat exchanger ( 51 ) and a second adsorption heat exchanger ( 52 ) on which adsorbent for adsorbing moisture in air is supported and in which refrigerant reversibly circulates to perform a vapor compression refrigeration cycle, and is configured so that refrigerant circulation in the refrigerant circuit ( 50 ) is reversibly switched to alternately perform an adsorption process and a recovery process with the adsorbent in the adsorption heat exchangers ( 51 ,  52 ), and the humidity of air passing through the adsorption heat exchanger ( 51 ,  52 ) is adjusted, the humidity control apparatus, comprising:
 an auxiliary heat exchanger ( 61 ) configured to preheat recovery air to be supplied to the adsorption heat exchanger ( 51 ,  52 ), which is provided in the refrigerant circuit ( 50 ), and is arranged on an upstream side of the adsorption heat exchanger ( 51 ,  52 ) in a recovery air flow; and   a refrigerant adjusting mechanism ( 62 ) configured to adjust an amount of refrigerant flowing into the auxiliary heat exchanger ( 61 ), which is provided in the refrigerant circuit ( 50 ).   
     
     
         2 . The humidity control apparatus of  claim 1 , wherein
 the refrigerant circuit ( 50 ) includes a main circuit ( 50   a ) having the compressor ( 53 ), the main expansion mechanism ( 55 ), and the adsorption heat exchangers ( 51 ,  52 ), and an auxiliary circuit ( 60 ) which is connected to the main circuit ( 50   a ), and into which high-pressure refrigerant flows,   the auxiliary heat exchanger ( 61 ) is provided in the auxiliary circuit ( 60 ), and   the refrigerant adjusting mechanism ( 62 ) is switchable between a state in which an inflow of high-pressure refrigerant into the auxiliary circuit ( 60 ) is allowed, and a state in which the inflow of high-pressure refrigerant into the auxiliary circuit ( 60 ) is blocked.   
     
     
         3 . The humidity control apparatus of  claim 2 , wherein
 the auxiliary circuit ( 60 ) includes an expansion bypass line ( 64 ) configured to bypass the main expansion mechanism ( 55 ) of the main circuit ( 50   a ), and   an auxiliary expansion mechanism ( 66 ) provided on a downstream side of the auxiliary heat exchanger ( 61 ) of the expansion bypass line ( 64 ) serves as the refrigerant adjusting mechanism ( 62 ).   
     
     
         4 . The humidity control apparatus of  claim 3 , further comprising:
 a bridge circuit ( 110 ) configured so that refrigerant constantly flows in one direction, and provided in a liquid line ( 50   b ) of the main circuit ( 50   a ),   wherein the main expansion mechanism ( 55 ) is arranged in a one-way path ( 119 ) connecting between one middle point and the other middle point in the bridge circuit ( 110 ), and   both ends of the expansion bypass line ( 64 ) are connected to the one-way path ( 119 ) of the bridge circuit ( 110 ) so as to bypass the main expansion mechanism ( 55 ).   
     
     
         5 . The humidity control apparatus of  claim 4 , wherein
 pipes ( 111 - 114 ) including check valves ( 115 - 118 ) are connected together to form the bridge circuit ( 110 ), and   the main circuit ( 50   a ) includes an auxiliary line ( 58 ) which connects an upstream side of the main expansion mechanism ( 55 ) of the one-way path ( 119 ) to the liquid line ( 50   b ) between the bridge circuit ( 110 ) and one of the adsorption heat exchangers ( 51 ,  52 ), and which has a capillary tube ( 59 ).   
     
     
         6 . The humidity control apparatus of  claim 3 , wherein
 the expansion bypass line ( 64 ) includes the bridge circuit ( 110 ) in which refrigerant constantly flows in one direction,   the auxiliary heat exchanger ( 61 ) is arranged in the one-way path ( 119 ) connecting between the one middle point and the other middle point in the bridge circuit ( 110 ), and   the auxiliary expansion valve ( 66 ) is arranged on the downstream side of the auxiliary heat exchanger ( 61 ) in the one-way path ( 119 ).   
     
     
         7 . The humidity control apparatus of  claim 2 , wherein
 the both ends of the auxiliary circuit ( 60 ) are connected to a high-pressure line ( 50   c ) on a discharge side of the compressor ( 53 ), and   the refrigerant adjusting mechanism ( 62 ) is switchable between a state in which refrigerant discharged from the compressor ( 53 ) flows through the high-pressure line ( 50   c ) of the main circuit ( 50   a ) and a state in which the refrigerant flows through the auxiliary circuit ( 60 ).   
     
     
         8 . The humidity control apparatus of  claim 2 , wherein
 the auxiliary circuit ( 60 ) includes a first auxiliary circuit ( 60   a ) and a second auxiliary circuit ( 60   b ), each of which is connected to the liquid line ( 50   b ) between an associated one of the adsorption heat exchangers ( 51 ,  52 ) and the main expansion mechanism ( 55 ) in the main circuit ( 50   a ) at both ends,   the auxiliary heat exchanger ( 61 ) includes a first auxiliary heat exchanger ( 61   a ) provided in the first auxiliary circuit ( 60   a ), and a second auxiliary heat exchanger ( 61   b ) provided in the second auxiliary circuit ( 60   b ), and   the refrigerant adjusting mechanism ( 62 ) is switchable between a state in which liquid refrigerant flows through the liquid line ( 50   b ) of the main circuit ( 50   a ) and a state in which the liquid refrigerant flows through the first auxiliary circuit ( 60   a ) or the second auxiliary circuit ( 60   b ).   
     
     
         9 . The humidity control apparatus of  claim 2 , further comprising:
 the bridge circuit ( 110 ) configured so that refrigerant constantly flows in one direction, and provided in the liquid line ( 50   b ) of the main circuit ( 50   a ),   wherein the main expansion mechanism ( 55 ) is arranged in the one-way path ( 119 ) connecting between the one middle point and the other middle point in the bridge circuit ( 110 ),   the both ends of the auxiliary circuit ( 60 ) are connected to the upstream side of the main expansion mechanism ( 55 ) in the one-way path ( 119 ) of the bridge circuit ( 110 ), and   the refrigerant adjusting mechanism ( 62 ) is switchable between a state in which liquid refrigerant flows through the main circuit ( 50   a ) of the one-way path ( 119 ) of the bridge circuit ( 110 ), and a state in which the liquid refrigerant flows through the auxiliary circuit ( 60 ).   
     
     
         10 . The humidity control apparatus of  claim 9 , wherein
 a noise canceling unit ( 65 ) is provided on an upstream side of the auxiliary heat exchanger ( 61 ) in the auxiliary circuit ( 60 ).   
     
     
         11 . The humidity control apparatus of  claim 1 , wherein
 the main expansion mechanism ( 55 ) includes a first expansion mechanism ( 55   a ) and a second expansion mechanism ( 55   b ), and the first expansion mechanism ( 55   a ), the auxiliary heat exchanger ( 61 ), and the second expansion mechanism ( 55   b ) are connected together in series in this order, and   the first expansion mechanism ( 55   a ) or the second expansion mechanism ( 55   b ) positioned between the adsorption heat exchanger ( 51 ,  52 ) performing the recovery process, and the auxiliary heat exchanger ( 61 ) serves as the refrigerant adjusting mechanism ( 62 ).   
     
     
         12 . The humidity control apparatus of  claim 1 , further comprising:
 the bridge circuit ( 110 ) configured so that refrigerant constantly flows in one direction, and provided in the liquid line ( 50   b ) of the main circuit ( 50   a ),   wherein the main expansion mechanism ( 55 ) is arranged in the one-way path ( 119 ) connecting between the one middle point and the other middle point in the bridge circuit ( 110 ),   the auxiliary heat exchanger ( 61 ) is provided on the upstream side of the main expansion mechanism ( 55 ) of the one-way path ( 119 ) of the bridge circuit ( 110 ), and   the refrigerant adjusting mechanism ( 62 ) includes a heat exchange bypass line ( 67 ), one end of which is connected to the discharge side of the compressor ( 53 ), and the other end of which is connected to the upstream side of the auxiliary heat exchanger ( 61 ) of the one-way path ( 119 ) of the bridge circuit ( 110 ), and a switching unit ( 68 ) configured to switch between a state in which refrigerant discharged from the compressor ( 53 ) flows through the heat exchange bypass line ( 67 ) and a state in which circulation of the refrigerant through the heat exchange bypass line ( 67 ) is blocked.