JP2018105588A - heat pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat pump capable of reliably continuing operation of an engine driving compressor and/or motor compressor, even in a case where when a temperature of air subjected to heat exchange by a heat source side heat exchanger is extremely low, cooling operation is performed.SOLUTION: A heat pump is configured such that an engine drive compressor 11 and a motor compressor 12 share a refrigerant circuit, which stores the engine drive compressor 11 and the motor compressor 12 in a common package 102a to circulate refrigerant. The heat pump is configured to change condensation capacity of a heat source side heat exchanger 20, and in a case of performing cooling operation, when a temperature of air subjected to heat exchange in the heat source side heat exchanger 20 is not more than a preset temperature, make the condensation capacity of the heat source side heat exchanger 20 smaller than maximum condensation capacity.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a heat pump that drives a compressor that compresses a refrigerant to control the temperature by the heat of condensation or evaporation of the refrigerant.

  A heat pump that drives a compressor that compresses a refrigerant and controls the temperature by the heat of condensation or evaporation of the refrigerant is generally a heat source side heat exchanger that exchanges heat between the refrigerant and air (specifically, outside air). (Specifically, an outdoor heat exchanger) and a use side heat exchanger (for example, an indoor heat exchanger) for exchanging heat between a temperature control target (for example, indoor air) and a refrigerant.

  Then, the heat pump circulates the refrigerant between the heat source side heat exchanger and the use side heat exchanger while repeating the state in which the refrigerant is depressurized to a low temperature and the state in which the refrigerant is pressurized to a high temperature. In the use-side heat exchanging unit, a cooling operation for cooling a temperature control target (for example, indoor air) (for example, cooling the room) and a heating operation for heating the temperature control target (for example, indoor air) (for example, heating the room) And is supposed to run. Specifically, in the use side heat exchanger, the refrigerant evaporates during the cooling operation and condenses the refrigerant during the heating operation, while the heat source side heat exchanger condenses the refrigerant during the cooling operation and performs the heating operation. When the refrigerant evaporates.

  As such a conventional heat pump, for example, Patent Document 1 discloses that an engine-driven compressor and an electric compressor are housed in a common package (specifically, a casing) and a refrigerant circuit that circulates a refrigerant is defined as an engine-driven compressor. A heat pump shared with an electric compressor is disclosed.

  Such a conventional heat pump has the following inconveniences when the cooling operation is performed when the temperature of the air exchanged by the heat source side heat exchanger is excessively low.

  That is, when performing the cooling operation, the temperature of the air (specifically, the outside air) that is heat-exchanged by the heat source side heat exchanger (specifically, the outdoor heat exchanger, in this case, the condenser) is the refrigerant condensing temperature ( More specifically, when the temperature is excessively low with respect to 40 ° C. or higher (for example, about 50 ° C.) [specifically, when the temperature is low in the autumn or spring, especially in winter, the temperature is low, for example, about 10 ° C. or lower] The condensation capacity necessary for condensing the refrigerant in the heat exchanger becomes excessive with respect to the evaporation capacity necessary for evaporating the refrigerant in the use side heat exchanger (for example, the indoor heat exchanger, in this case, the evaporator).

  As a result, the condensing pressure necessary for condensing the refrigerant in the engine-driven compressor and / or the electric compressor is lowered, and accordingly, the discharge pressure and the suction of the refrigerant of the engine-driven compressor and / or the electric compressor are reduced accordingly. The pressure difference from the pressure is reduced, and as a result, the rotational speed per unit time of the engine-driven compressor and / or the electric compressor (hereinafter simply referred to as rotational speed) is reduced. In some cases, the rotational speed of the engine-driven compressor and / or the electric compressor cannot meet the requirements for continuing the operation of the engine-driven compressor and / or the electric compressor. Here, the requirements are (1) the allowable operating range of the engine-driven compressor and / or the electric compressor, (2) oil supply required for refrigerant conveyance, and in the case of an oil supply type compressor, oil supply to the compressor There are three measures: ensuring the necessary refrigerant high / low pressure difference, and (3) ensuring the refrigerant low pressure for ensuring the refrigerant evaporation temperature above the freezing temperature of the evaporator. In the case of an independent operation of the engine-driven compressor, when the condenser capacity becomes excessive, the refrigerant refrigeration capacity of the condenser and the evaporator can be obtained by using a refrigerant auxiliary evaporator that uses engine waste heat as a heat source. However, this is particularly problematic because the refrigerant auxiliary evaporator that uses engine waste heat as a heat source cannot be used when the electric compressor is switched to a single operation.

JP2013-250004A

  In this regard, Patent Document 1 discloses that only an engine-driven compressor is used as a refrigerant compression unit when a heating operation (heating operation) is started in a hybrid air conditioner from a situation where the outdoor air temperature is stopped. Is activated, and heat exchange is performed between the refrigerant and the engine coolant, thereby heating the refrigerant in a short time (see paragraph [0031] of Patent Document 1).

  However, Patent Document 1 merely discloses a configuration in which a refrigerant whose temperature is low under a low outside air temperature is heated by high-temperature engine cooling water during operation of the engine-driven compressor during heating operation. When the cooling operation is performed when the temperature of the air heat exchanged by the side heat exchanger is excessively low, the condensation pressure in the heat source side heat exchanger increases, resulting in a state where the condensation pressure is reduced and the engine is driven. No configuration is shown to solve the problem that the operation of the compressor and / or the electric compressor cannot be continued.

  Therefore, the present invention is a heat pump in which an engine driven compressor and an electric compressor are housed in a common package and a refrigerant circuit that circulates the refrigerant is shared by the engine driven compressor and the electric compressor. Provided is a heat pump capable of reliably continuing the operation of an engine-driven compressor and / or an electric compressor even when a cooling operation is performed when the temperature of the air heat-exchanged by the exchanger is excessively low For the purpose.

  In order to solve the above-mentioned problems, the present invention provides the following heat pumps of the first aspect and the second aspect.

(1) Heat pump according to the first aspect The heat pump according to the first aspect of the present invention has a refrigerant circuit that houses the engine-driven compressor and the electric compressor in a common package and circulates the refrigerant with the engine-driven compressor and the A heat pump shared with an electric compressor, wherein the heat source side heat exchanger is configured such that the condensation capacity of the heat source side heat exchanger can be changed, and when performing a cooling operation, the heat source side heat exchanger When the temperature of the air to be heat exchanged at or below is equal to or lower than a predetermined temperature, the condensation capacity of the heat source side heat exchanger is made smaller than the maximum condensation capacity.

  In the heat pump of the first aspect, the heat source side heat exchanger is configured by a plurality of units, and the heat source side heat exchange is performed in the flow direction of the discharge gas refrigerant discharged from the engine driven compressor and / or the electric compressor. When an on-off valve is provided in at least one branch path among the branch paths upstream of the heater and the cooling operation is performed, the temperature of the air exchanged in the heat source side heat exchanger is equal to or lower than the predetermined temperature Moreover, the aspect which controls the said on-off valve so that the condensation capability of the said heat source side heat exchanger may become smaller than the maximum condensation capability can be illustrated.

(2) Heat Pump of Second Aspect The heat pump of the second aspect according to the present invention includes a refrigerant circuit that houses an engine-driven compressor and an electric compressor in a common package and circulates refrigerant, and the engine-driven compressor and the A heat pump shared by an electric compressor, wherein the engine driven compressor and / or the branch path branched to the upstream side of the heat source side heat exchanger in the flow direction of the discharge gas refrigerant discharged from the electric compressor In the case where an auxiliary heat exchanger for exchanging heat between the refrigerant and the engine cooling water for cooling the engine is provided and the cooling operation is performed, the temperature of the air exchanged by the heat source side heat exchanger is a predetermined temperature. In the following cases, when the engine is stopped and the temperature of the engine coolant is higher than the temperature of air exchanged by the heat source side heat exchanger, the discharge The flow direction of the outgas refrigerant is configured to be directed to the auxiliary heat exchanger.

  In the heat pumps of the first aspect and the second aspect, the predetermined temperature is an excessively low temperature with respect to a refrigerant condensation temperature (specifically, 40 ° C. or higher, for example, about 50 ° C.), for example, 10 ° C. The following can be mentioned.

  According to the present invention, even when the cooling operation is performed when the temperature of the air heat exchanged by the heat source side heat exchanger is excessively low, the operation of the engine-driven compressor and / or the electric compressor is reliably continued. It becomes possible to do.

It is a schematic block diagram of an example of the heat pump which concerns on 1st Embodiment. It is a schematic block diagram which shows the cooling operation state which is performing the cooling operation in the heat pump shown in FIG. It is a flowchart which shows an example of the control action performed at the time of cooling operation by the control apparatus in the heat pump shown in FIG. FIG. 2 is a schematic block diagram illustrating a heating operation state in which a heating operation is performed in the heat pump illustrated in FIG. 1. It is a schematic block diagram of an example of the heat pump which concerns on 2nd Embodiment. FIG. 6 is a schematic block diagram illustrating a cooling operation state in which a cooling operation is performed in the heat pump illustrated in FIG. 5. It is a flowchart which shows an example of the control action performed at the time of cooling operation by the control apparatus in the heat pump shown in FIG. FIG. 6 is a schematic block diagram showing a configuration for radiating engine cooling water when the engine cooling water temperature is equal to or higher than a predetermined upper limit temperature in the heat pump shown in FIG. 5. FIG. 6 is a schematic block diagram illustrating a heating operation state in which a heating operation is performed in the heat pump illustrated in FIG. 5.

  Embodiments according to the present invention will be described below with reference to the drawings.

<First Embodiment>
FIG. 1 is a schematic block diagram of an example of a heat pump 100A according to the first embodiment.

  The heat pump 100A shown in FIG. 1 drives the compression part 10 which compresses a refrigerant | coolant, and adjusts temperature with the condensation heat | fever of a refrigerant | coolant or the heat of evaporation. Here, the temperature control is, for example, temperature control of indoor air or air in the refrigerator or freezer when the heat pump 100A functions as an air conditioner, and for chiller when the heat pump 100A functions as a chiller. The temperature of the circulating fluid is adjusted. The circulating fluid may be any fluid as long as it acts as a heat medium, and representatively, water can be exemplified. However, it is not limited thereto, and the circulating fluid may be, for example, water containing an antifreeze.

  The heat pump 100A includes a compressor 10 that sucks and discharges refrigerant, a heat source side heat exchanger 20 that exchanges heat between the refrigerant and air (specifically, outside air), and a heat source for the heat source side heat exchanger 20. A side heat exchanger fan 30, a regulating valve 40 that adjusts the flow rate of the refrigerant, a use side heat exchanger 50 that exchanges heat between the temperature adjustment target and the refrigerant, a drive source 60 that drives the compressor 10, A refrigerant circuit 110 for circulating the refrigerant and a control device 120 are provided.

  Here, the temperature control target is, for example, indoor air or air in a refrigerator or freezer when the heat pump 100A functions as an air conditioner, and circulating fluid when the heat pump 100A functions as a chiller.

  Then, the heat pump 100A circulates the refrigerant between the heat source side heat exchanger 20 and the use side heat exchanger 50 while repeating the state in which the refrigerant is depressurized to a low temperature and the refrigerant is pressurized to a high temperature. As described later, in the use-side heat exchanging unit 101, a cooling operation for cooling the temperature adjustment target (for example, indoor air) (for example, cooling the room) and heating the temperature adjustment target (for example, indoor air) ( For example, a heating operation for heating the room is performed.

  The heat pump 100A includes both the engine-driven compressor 11 and the electric compressor 12, and is a so-called hybrid heat pump.

  In the heat pump 100A, the engine-driven compressor 11 and the electric compressor 12 are provided with a refrigerant circuit 110 in which the engine-driven compressor 11 and the electric compressor 12 are housed in a common package 102a (specifically, a casing) to circulate the refrigerant. And shared.

  Specifically, the compression unit 10 includes an engine-driven compressor 11 that is a compressor driven by the engine 61 and an electric compressor 12 that is a compressor driven by the electric motor 62. The engine drive compressor 11 and the electric compressor 12 are connected in parallel.

  The drive source 60 includes an engine 61 that drives the engine-driven compressor 11 and an electric motor 62 that drives the electric compressor 12.

  The engine-driven compressor 11 may be obtained by connecting a plurality of engine-driven compressors in parallel. Similarly, the electric compressor 12 may include a plurality of electric compressors connected in parallel.

  The engine 61 may be, for example, an engine using gas fuel as a fuel (so-called gas engine) or an engine using liquid fuel as fuel. In this example, the engine 61 is a gas engine. Therefore, the heat pump 100A functions as a gas heat pump (GHP: Gas Heat Pump). Further, since the heat pump 100A uses the electric motor 62 in addition to the engine 61 as the drive source 60, the heat pump 100A also functions as an electric heat pump (EHP).

  The heat pump 100 </ b> A may be operated by both the engine-driven compressor 11 and the electric compressor 12 when operated by only the engine-driven compressor 11, when operated by only the electric compressor 12. When the engine is driven by both the engine-driven compressor 11 and the electric compressor 12, the ratios of the operation capacities of the engine-driven compressor 11 and the electric compressor 12 are the engine speed that is the speed of the engine 61 and the rotation of the electric motor 62. This can be determined by controlling the number of motor revolutions.

  The heat source side heat exchanger 20 is configured such that the condensation capacity of the heat source side heat exchanger 20 can be changed. In this example, the heat source side heat exchanger 20 is composed of a plurality of (two in this example) units.

  Specifically, the heat source side heat exchanger 20 includes a plurality of heat source side heat exchanger units 20 (1) to 20 (n) (n is an integer of 2 or more, in this example, n = 2) in parallel as a plurality of units. Connected.

  The heat pump 100A further includes an on-off valve 21. The on-off valve 21 is a heat source side heat exchanger in the flow direction W of a high-pressure gas state refrigerant (hereinafter referred to as high-pressure gas refrigerant) that is a discharge gas refrigerant discharged from the engine-driven compressor 11 and / or the electric compressor 12. Of the upstream branch paths of the units 20 (1) to 20 (n), at least one branch path (in this example, the branch path to the heat source side heat exchanger unit 20 (n)) is provided.

  The on-off valve 21 is configured to switch between a closed state and an open state according to an instruction signal from the control device 120. Therefore, the control device 120 controls the opening / closing valve 21 to open / close among the branch paths upstream of the heat source side heat exchanger units 20 (1) to 20 (n) in the flow direction W of the discharge gas refrigerant. Condensing capacity of the heat source side heat exchanger 20 by controlling the supply of refrigerant to the heat source side heat exchanger unit 20 (i) (i is any integer from 1 to n) on the branch path provided with the valve 21 Can be changed.

  In addition, if the control apparatus 120 opens all the on-off valves 21, the condensing capacity of the heat source side heat exchanger 20 will be the maximum condensing capacity. On the other hand, when the on-off valve 21 is provided leaving at least one of the upstream branch paths of the heat source side heat exchanger units 20 (1) to 20 (n), the control device 120 is not When the on-off valve 21 is closed, and the on-off valves 21 are provided in all the branch paths upstream of the heat source side heat exchanger units 20 (1) to 20 (n), the control device 120 is the most. When all the other on-off valves 21 are closed with the on-off valves 21 corresponding to the heat source side heat exchanger unit 20 (i) having a small condensing capacity being closed, the condensing capacity of the heat source side heat exchanger 20 becomes the minimum condensing capacity.

  The regulating valve 40 functions as an expansion valve, and in this example, includes a first regulating valve 41 (1) to 41 (n) that can be closed and a second regulating valve 42 that can be closed. The first regulating valves 41 (1) to 41 (n) correspond to the heat source side heat exchanger units 20 (1) to 20 (n), respectively, and the heat source side heat exchanger unit 20 in the flow direction W of the discharge gas refrigerant. (1) to 20 (n) are provided on the downstream side. In addition, the heat pump 100A is a check valve that is provided in parallel with the first adjustment valves 41 (1) to 41 (n) and blocks the refrigerant that is directed to the heat source side heat exchanger units 20 (1) to 20 (n). 40a-40a is further provided.

  The first regulating valves 41 (1) to 41 (n) may be a plurality of regulating valves connected in parallel. The 2nd regulating valve 42 and the use side heat exchanger 50 comprise the use side heat exchange part 101, and the use side heat exchange part 101 is taken as the indoor unit in this example. Moreover, the heat source side heat exchange part 102 provided with the structural member except the 2nd adjustment valve 42, the utilization side heat exchanger 50, and a pair of connecting piping 110a, 110b among the structural members of the heat pump 100A is an outdoor in this example. It is supposed to be a machine.

  The heat pump 100A is a refrigerant auxiliary evaporator 72 (sub-evaporator) that exchanges heat between the receiver 71 that collects liquid refrigerant and the refrigerant and exhaust heat of the engine 61 (in this example, heat of engine cooling water that cools the engine 61). And a regulating valve 73 for the refrigerant auxiliary evaporator that can be closed. Here, the engine cooling water is a concept including not only water but also water containing antifreeze.

  The refrigerant circuit 110 includes a compressor 10 (the engine-driven compressor 11 and the electric compressor 12), a heat source side heat exchanger 20, first adjustment valves 41 (1) to 41 (n), check valves 40a to 40a, A second regulating valve 42, a use side heat exchanger 50, a receiver 71, a refrigerant auxiliary evaporator 72, and a refrigerant auxiliary evaporator adjusting valve 73 are provided.

  The refrigerant circuit 110 includes a four-way valve 111, a bridge circuit 112, a first refrigerant path 113a to a tenth refrigerant path 113j, and a pair of connecting pipes 110a and 110b.

  The four-way valve 111 is configured to switch between a first connection state (the state shown in FIG. 1) and a second connection state according to an instruction signal from the control device 120. The first connection state is a state where the inflow port 111a and the other connection port 111d are connected, and the one connection port 111c and the outflow port 111b are connected. The second connection state is a state in which the inflow port 111a and the one connection port 111c are connected, and the other connection port 111d and the outflow port 111b are connected. Accordingly, the control device 120 can switch the refrigerant flow direction W by controlling the operation of the four-way valve 111. In addition, in FIG. 1, the 1st connection state (The cooling operation state which is performing the cooling operation) is shown.

  The bridge circuit 112 includes four check valves (a first check valve 112a, a second check valve 112b, a third check valve 112c, and a fourth check valve 112d). The bridge circuit 112 includes a first check valve row 1121 including two check valves (a first check valve 112a and a second check valve 112b), and the remaining two check valves (a third check valve 112c). And a second check valve row 1122 including a fourth check valve 112d).

  The first check valve row 1121 is configured such that the first check valve 112a and the second check valve 112b are connected in series so that the refrigerant flow direction W is the same. The second check valve row 1122 is configured such that the third check valve 112c and the fourth check valve 112d are connected in series so that the refrigerant flow direction W is the same. The first check valve row 1121 and the second check valve row 1122 are connected in parallel so that the refrigerant flow direction W is the same.

  In the bridge circuit 112, a connection point between the first check valve 112a and the second check valve 112b is a first intermediate connection point P1, and between the first check valve 112a and the third check valve 112c. Is the outflow connection point P2, the connection point between the third check valve 112c and the fourth check valve 112d is the second intermediate connection point P3, and the second check valve 112b and the fourth check valve A connection point between the stop valve 112d and the stop valve 112d is an inflow connection point P4.

  The first refrigerant paths 113a to 113a connect the discharge ports 10a to 10a of the compressor 10 (the engine driven compressor 11 and the electric compressor 12) and the inlet 111a of the four-way valve 111. The second refrigerant path 113b connects the outlet 111b of the four-way valve 111 and the inlets 10b to 10b of the compressor 10 (the engine driven compressor 11 and the electric compressor 12). The third refrigerant path 113c connects the other connection port 111d of the four-way valve 111 and the one connection ports 20a to 20a of the heat source side heat exchanger units 20 (1) to 20 (n). The fourth refrigerant paths 113d to 113d connect the other connection ports 20b to 20b of the heat source side heat exchanger units 20 (1) to 20 (n) and the first intermediate connection point P1 of the bridge circuit 112. The fifth refrigerant path 113e connects the outflow connection point P2 of the bridge circuit 112 and the refrigerant inflow port 71a of the receiver 71. The sixth refrigerant path 113f connects the refrigerant outlet 71b of the receiver 71 and the inflow connection point P4 of the bridge circuit 112. The seventh refrigerant path 113g connects the second intermediate connection point P3 of the bridge circuit 112 and one communication pipe 110a connected to one refrigerant connection port 50a of the use side heat exchanger 50. The eighth refrigerant path 113h connects the other connection pipe 110b connected to the other refrigerant connection port 50b of the use side heat exchanger 50 and the one connection port 111c of the four-way valve 111. The ninth refrigerant path 113i connects the inflow connection point P4 of the bridge circuit 112 and the refrigerant inlet 72a of the refrigerant auxiliary evaporator 72. The tenth refrigerant path 113j connects the refrigerant outlet 72b of the refrigerant auxiliary evaporator 72 and the junction P5 in the middle of the second refrigerant path 113b. Here, the downstream side (compression unit 10 side) of the second refrigerant path 113b from the junction P5 is a junction path 113b1.

  The receiver 71 temporarily stores the liquid refrigerant from the fifth refrigerant path 113e. The first regulating valves 41 (1) to 41 (n) constituting the regulating valve 40 are provided in the fourth refrigerant paths 113d to 113d, and the opening degree is adjusted during the heating operation to control the flow rate of the refrigerant. The check valves 40 a to 40 a cause the refrigerant to flow from the heat source side heat exchanger units 20 (1) to 20 (n) to the first intermediate connection point P 1 of the bridge circuit 112, while the first intermediate connection point of the bridge circuit 112. The refrigerant flow from P1 to the heat source side heat exchanger units 20 (1) to 20 (n) is blocked. The second regulating valve 42 constituting the regulating valve 40 is provided in the refrigerant path 51 between one communication pipe 110 a and one refrigerant connection port 50 a of the usage side heat exchanger 50 in the usage side heat exchange unit 101. The opening degree is adjusted during the cooling operation to control the flow rate of the refrigerant. The refrigerant auxiliary evaporator adjusting valve 73 is provided in the ninth refrigerant path 113i, and the opening degree is adjusted during the heating operation or the cooling operation to control the flow rate of the refrigerant.

  In the present embodiment, heat pump 100A further includes an oil separator 81 and an accumulator 82.

  The oil separator 81 is provided in the first refrigerant path 113a. The oil separator 81 separates the lubricating oil of the compressor 10 (the engine-driven compressor 11 and the electric compressor 12) contained in the refrigerant and supplies the separated lubricating oil to the valve 81a. It returns to the compression part 10 (the engine drive compressor 11 and the electric compressor 12) via -81a (specifically electromagnetic valve). The accumulator 82 is provided in the merging path 113b1 of the second refrigerant path 113b, and has not completely evaporated in the heat source side heat exchanger 20, the use side heat exchanger 50, and the refrigerant auxiliary evaporator 72 acting as an evaporator. Separate the refrigerant liquid.

  In the present embodiment, the heat pump 100A further includes a first switching valve 114, and the refrigerant circuit 110 further includes an eleventh refrigerant path 113k.

  The eleventh refrigerant path 113k connects the bottom opening 82a of the accumulator 82 and the refrigerant path closer to the compression unit 10 than the accumulator 82 of the merging path 113b1. The first switching valve 114 is provided in the eleventh refrigerant path 113k, and switches between a distribution state in which the refrigerant flows in the eleventh refrigerant path 113k and a blocking state in which the refrigerant distribution is blocked by an opening / closing operation.

  In the present embodiment, the heat pump 100A further includes a supercooling heat exchanger 91 and a closeable supercooling heat exchanger regulating valve 92, and the refrigerant circuit 110 further includes a twelfth refrigerant path 113l. Yes.

  The twelfth refrigerant path 113l connects the inflow connection point P4 of the bridge circuit 112 and the refrigerant path closer to the compression unit 10 than the first switching valve 114 of the eleventh refrigerant path 113k. The subcooling heat exchanger 91 has an inflow port 91a on the receiver 71 side and an outflow port 91b on the inflow connection point P4 side of the bridge circuit 112 in communication with the sixth refrigerant path 113f, and the adjustment valve 92 side for the subcooling heat exchanger The inlet 91c and the outlet 91d on the accumulator 82 side communicate with the twelfth refrigerant path 113l. The adjustment valve 92 for the supercooling heat exchanger is provided in the refrigerant path closer to the inflow connection point P4 of the bridge circuit 112 than the supercooling heat exchanger 91 of the twelfth refrigerant path 113l, and the opening degree is adjusted during the cooling operation. To control the flow rate of the refrigerant. The supercooling heat exchanger 91 includes a refrigerant that flows in the sixth refrigerant path 113f during the cooling operation and a refrigerant that flows in the refrigerant path closer to the supercooling heat exchanger 91 than the adjustment valve 92 for the supercooling heat exchanger in the twelfth refrigerant path 113l. Heat exchange between. Thereby, the cooling efficiency of the refrigerant flowing through the sixth refrigerant path 113f during the cooling operation can be improved.

  The first regulating valves 41 (1) to 41 (n), the second regulating valve 42, the refrigerant auxiliary evaporator regulating valve 73 and the supercooling heat exchanger regulating valve 92 are all opened by an instruction signal from the control device 120. Can be adjusted. Accordingly, the control device 120 controls the operation of the first adjustment valves 41 (1) to 41 (n), the second adjustment valve 42, the refrigerant auxiliary evaporator adjustment valve 73, and the subcooling heat exchanger adjustment valve 92. The flow of the refrigerant in the refrigerant circuit 110 can be adjusted.

  The engine drive compressor 11 constituting the compression unit 10 is connected to the engine 61 via a clutch 11a. The clutch 11a is in a connected state in which driving force is transmitted from the engine 61 to the engine-driven compressor 11 and in a disconnected state in which transmission of driving force from the engine 61 to the engine-driven compressor 11 is interrupted by an instruction signal from the control device 120. It is supposed to take.

  The heat pump 100A includes a discharge pressure sensor 151 (high pressure sensor), a suction pressure sensor 152 (low pressure sensor), a first suction temperature sensor 161, a second suction temperature sensor 162, a third suction temperature sensor 163, an engine speed sensor 171 and a motor. A rotation speed sensor 172 is further provided.

  The discharge pressure sensor 151 detects the discharge pressure of the refrigerant in the discharge path of the compressor 10 (the engine driven compressor 11 and the electric compressor 12). Specifically, the discharge pressure sensor 151 is provided in the refrigerant path on the upstream side (compression unit 10 side) of the oil separator 81 in the first refrigerant path 113a, and upstream of the oil separator 81 in the first refrigerant path 113a. The pressure of the refrigerant in is detected.

  The suction pressure sensor 152 detects the suction pressure of the refrigerant in the suction path of the compressor 10 (the engine driven compressor 11 and the electric compressor 12). Specifically, the suction pressure sensor 152 is provided in the refrigerant path on the downstream side (compression unit 10 side) with respect to the junction point P5 of the second refrigerant path 113b, and is downstream of the junction point P5 of the second refrigerant path 113b. The pressure of the refrigerant in is detected.

  The first suction temperature sensor 161, the second suction temperature sensor 162, and the third suction temperature sensor 163 all detect the refrigerant suction temperature in the suction path of the compressor 10 (the engine-driven compressor 11 and the electric compressor 12). . Each temperature sensor is a thermistor in this example.

  Specifically, the first suction temperature sensor 161 is provided in the refrigerant path on the upstream side (confluence point P5 side) of the accumulator 82 of the confluence path 113b1 of the second refrigerant path 113b, and is more than the accumulator 82 of the confluence path 113b1. The temperature of the refrigerant on the upstream side is detected.

  The second suction temperature sensor 162 is provided in the refrigerant path on the downstream side (compression section 10 side) from the connection part of the merging path 113b1 of the second refrigerant path 113b with the eleventh refrigerant path 113k. The temperature of the refrigerant | coolant in a downstream is detected rather than the connection part with the 11th refrigerant | coolant path | route 113k.

  The third suction temperature sensor 163 is provided in the refrigerant path on the downstream side (compression section 10 side) of the eleventh refrigerant path 113k connected to the twelfth refrigerant path 113l, and the twelfth of the eleventh refrigerant path 113k. The temperature of the refrigerant | coolant in a downstream is detected rather than the connection part with the refrigerant path 113l.

  The engine speed sensor 171 is provided in the engine 61 and detects an engine speed that is the speed of the engine 61.

  The motor rotation speed sensor 172 is provided in the electric motor 62 and detects the motor rotation speed that is the rotation speed of the electric motor 62.

  The heat pump 100 </ b> A includes engine-driven compressor rotational speed detection means (specifically, an engine-driven compressor rotational speed sensor) that detects an engine-driven compressor rotational speed that is the rotational speed of the engine-driven compressor 11.

  For example, when the engine-driven compressor 11 and the engine 61 rotate at the same speed, the engine-driven compressor rotation speed detection means can also be used as the engine rotation speed sensor 171. On the other hand, when the engine-driven compressor 11 and the engine 61 are connected via a transmission drive mechanism such as a transmission pulley or a transmission, the engine-driven compressor rotational speed by the engine-driven compressor rotational speed detection means is The engine speed can be calculated from the engine speed obtained by the engine speed sensor 171 using the gear ratio. In this example, the engine-driven compressor 11 and the engine 61 rotate at the same speed, and the engine-driven compressor rotational speed detection means (specifically, the engine-driven compressor rotational speed sensor) The number sensor 171) is also used. In addition, as an engine drive compressor rotation speed detection means, the engine drive compressor rotation speed sensor which detects an engine drive compressor rotation speed directly, for example may be provided separately.

  The control device 120 controls the driving of the refrigerant circuit 110 based on detection signals from various sensors.

  Specifically, the control device 120 compresses the refrigerant sucked from the second refrigerant path 113b by the compressor 10 (the engine-driven compressor 11 and / or the electric compressor 12), and the compressed refrigerant enters the first refrigerant path 113a. Discharge. During the cooling operation, the control device 120 sets the four-way valve 111 in the first connection state to communicate the first refrigerant path 113a and the third refrigerant path 113c and to communicate the eighth refrigerant path 113h and the second refrigerant path 113b. . In addition, during the heating operation, the control device 120 sets the four-way valve 111 in the second connection state so as to communicate the first refrigerant path 113a and the eighth refrigerant path 113h, and connect the third refrigerant path 113c and the second refrigerant path 113b. Communicate.

  The heat source side heat exchanger 20 functions as a condenser that radiates and liquefies the refrigerant during the cooling operation, and functions as an evaporator that absorbs and vaporizes the refrigerant during the heating operation. The use-side heat exchanger 50 functions as a cooler (evaporator) that cools the temperature adjustment target (for example, indoor air) by the refrigerant absorbing heat during the cooling operation, and the refrigerant radiates heat during the heating operation. For example, it functions as a heater (condenser) for heating indoor air). The refrigerant auxiliary evaporator 72 and the supercooling heat exchanger 91 function as an evaporator that absorbs heat and vaporizes the refrigerant.

  The control device 120 includes a processing unit 121 including a microcomputer such as a CPU (Central Processing Unit), a nonvolatile memory such as a ROM (Read Only Memory), and a storage unit 122 including a volatile memory such as a RAM (Random Access Memory). And.

  The control device 120 controls the operation of various components by causing the processing unit 121 to load and execute a control program stored in advance in the ROM of the storage unit 122 on the RAM of the storage unit 122. .

  The control device 120 adjusts the flow rate of the refrigerant from the bridge circuit 112 toward the heat source side heat exchanger 20 during the heating operation by transmitting an instruction command to the first adjustment valves 41 (1) to 41 (n). Specifically, during the heating operation, the control device 120 determines the degree of superheat (the detected temperature with respect to the saturated vapor pressure temperature) based on the saturated vapor pressure temperature based on the detected pressure from the intake pressure sensor 152 and the detected temperature from the first intake temperature sensor 161. The first regulating valves 41 (1) to 41 (n) are caused to function as expansion valves that regulate the flow rate of the refrigerant according to the temperature difference between the first regulating valve 41 (1) and 41 (n). When check valves 40a to 40a are not provided, control device 120 can fully open first adjustment valves 41 (1) to 41 (n) during the cooling operation. Here, the saturated vapor pressure temperature is converted from a suction pressure of the compressor 10 (the engine driven compressor 11 and / or the electric compressor 12) detected by the suction pressure sensor 152 by a predetermined conversion formula or conversion table. can do.

  The control device 120 transmits an instruction command to the second regulating valve 42 to adjust the flow rate of the refrigerant from the bridge circuit 112 to the use side heat exchanger 50 during the cooling operation, and during the heating operation, the use side heat exchange. The flow rate of the refrigerant from the vessel 50 toward the bridge circuit 112 is adjusted. Specifically, during the cooling operation, the control device 120 adjusts the flow rate of the refrigerant according to the degree of superheat based on the saturated vapor pressure temperature based on the detected pressure from the suction pressure sensor 152 and the detected temperature from the first suction temperature sensor 161. The second adjustment valve 42 can be made to function as an expansion valve to perform, and the second adjustment valve 42 can be fully opened during the heating operation.

  The control device 120 adjusts the flow rate of the refrigerant from the bridge circuit 112 toward the refrigerant auxiliary evaporator 72 during the cooling operation or the heating operation by transmitting an instruction command to the refrigerant auxiliary evaporator adjusting valve 73.

  The control device 120 transmits an instruction command to the first switching valve 114 to open the first switching valve 114 during the cooling operation or the heating operation, so that the compression unit 10 (engine drive) is opened from the bottom surface opening 82a of the accumulator 82. While the refrigerant is circulated toward the compressor 11 and / or the electric compressor 12), the first switching valve 114 is closed and the compressor 10 (the engine-driven compressor 11 and / or the electric drive) is opened from the bottom opening 82a of the accumulator 82. Block the refrigerant flow to the compressor 12). Specifically, the control device 120 determines in advance the degree of superheat based on the saturated vapor pressure temperature based on the detected pressure from the suction pressure sensor 152 and the detected temperature from the second suction temperature sensor 162 during the cooling operation or the heating operation. When the value is equal to or greater than a predetermined value (first predetermined value), the first switching valve 114 is opened, and when the degree of superheat falls below a predetermined value (first predetermined value), the first switching valve 114 is closed. To do.

(Cooling operation)
Next, the operation of the cooling operation by the heat pump 100A according to the first embodiment will be described below with reference to FIGS.

  FIG. 2 is a schematic block diagram showing a cooling operation state in which the cooling operation is performed in the heat pump 100A shown in FIG. FIG. 2 shows a case where the engine is driven by both the engine driven compressor 11 and the electric compressor 12. The same applies to FIGS. 4, 6 and 9 described later. Moreover, the thick line and the thick broken line have shown the flow of the refrigerant | coolant. The same applies to FIG. 6 described later.

  In the example shown in FIG. 2, in the cooling operation, the control device 120 adjusts the opening of the second adjustment valve 42, the refrigerant auxiliary evaporator adjustment valve 73, and the subcooling heat exchanger adjustment valve 92, and opens the on-off valve 21. Alternatively, the closed state is set, and the first switching valve 114 is opened.

  In the heat pump 100A, when performing the cooling operation, the control device 120 switches the four-way valve 111 to the first connection state to connect the first refrigerant path 113a and the third refrigerant path 113c and to the eighth refrigerant path 113h and the second refrigerant path. The refrigerant path 113b is communicated. By doing so, the high-pressure gas refrigerant discharged from the compressor 10 (in this example, the engine-driven compressor 11 and the electric compressor 12) is transferred from the oil separator 81 of the first refrigerant path 113a to the four-way valve 111 and the third refrigerant path. It flows into the heat source side heat exchanger 20 via 113c.

  Specifically, when all the open / close valves 21 are open, the high-pressure gas refrigerant flows to all of the heat source side heat exchanger units 20 (1) to 20 (n), and when at least one open / close valve 21 is closed. The high-pressure gas refrigerant flows into the heat source side heat exchanger unit 20 (i) in which the on-off valve 21 is opened among the heat source side heat exchanger units 20 (1) to 20 (n). In this example, n and i are 2, and when the on-off valve 21 corresponding to the heat source side heat exchanger unit 20 (2) is opened, the high-pressure gas refrigerant is the heat source side heat exchanger unit 20 (1), When the on-off valve 21 corresponding to the heat source side heat exchanger unit 20 (2) is closed, it flows only to the heat source side heat exchanger unit 20 (1) (refer to the thick line and the thick broken line) (see FIG. (See bold line). The opening / closing operation of the opening / closing valve 21 will be described in detail later.

  The temperature of the high-pressure gas refrigerant flowing through the heat source side heat exchanger 20 is higher than the temperature of air (specifically, outside air) heat exchanged by the heat source side heat exchanger 20. For this reason, heat moves from the high-pressure gas refrigerant to the air (specifically, outside air). As a result, the high-pressure gas refrigerant loses heat of condensation and liquefies to become a high-pressure liquid refrigerant (hereinafter referred to as high-pressure liquid refrigerant). That is, in the cooling operation, the heat source side heat exchanger 20 functions as a refrigerant condenser that dissipates heat from the high-pressure gas refrigerant.

  The high pressure liquid refrigerant is supplied from the heat source side heat exchanger 20 to the fifth refrigerant path 113d through the check valve 40a, the fourth refrigerant path 113d, the first intermediate connection point P1, the first check valve 112a, and the outflow connection point P2. The refrigerant flows through the refrigerant path 113e, the receiver 71, and the supercooling heat exchanger 91 in the sixth refrigerant path 113f to the inflow connection point P4 of the bridge circuit 112. The inflow connection point P4 is on the inflow side of the second check valve 112b and the fourth check valve 112d, but the high-pressure liquid refrigerant described above flows to the outflow connection point P2 side. For this reason, the high-pressure liquid refrigerant does not flow toward the second check valve 112b and the third check valve 112c due to the pressure difference from the high-pressure liquid refrigerant flowing to the outflow connection point P2, and the fourth from the inflow connection point P4 to the fourth. It passes through the second regulating valve 42 via the check valve 112d, the second intermediate connection point P3, the seventh refrigerant path 113g, and the one connection pipe 110a.

  In the second regulating valve 42, the high-pressure liquid refrigerant expands to become a low-pressure gas-liquid two-phase refrigerant (hereinafter referred to as a low-pressure gas-liquid two-phase refrigerant), and the low-pressure gas-liquid two-phase refrigerant is a use side heat exchanger. 50 flows.

  The temperature of the low-pressure gas-liquid two-phase refrigerant flowing to the refrigerant circuit 110 side of the use side heat exchanger 50 is lower than the temperature of the temperature adjustment target side (in this example, the indoor air side) of the use side heat exchanger 50. For this reason, heat moves from the temperature adjustment target side (in this example, the indoor air side) to the low-pressure gas-liquid two-phase refrigerant. As a result, the low-pressure gas-liquid two-phase refrigerant is vaporized by obtaining evaporation heat, and becomes a refrigerant in a low-pressure gas state (hereinafter referred to as a low-pressure gas refrigerant). On the other hand, the temperature adjustment target side (in this example, the indoor air side) is cooled by the endothermic action of the refrigerant. That is, in the cooling operation, the second adjustment valve 42 functions as an expansion valve that expands the high-pressure liquid refrigerant to form a low-pressure gas-liquid two-phase refrigerant, and the use-side heat exchanger 50 absorbs the low-pressure gas-liquid two-phase refrigerant. It functions as a cooler for the temperature control target (in this example, indoor air).

  Thereafter, the low-pressure gas refrigerant flows from the use side heat exchanger 50 to the other communication pipe 110b and the eighth refrigerant path 113h. At this time, since the four-way valve 111 causes the eighth refrigerant path 113h and the second refrigerant path 113b to communicate with each other, the control device 120 causes the low-pressure gas refrigerant to pass through the accumulator 82 and the first switching on the second refrigerant path 113b. The air is sucked into the compression unit 10 via the valve 114.

  The high-pressure liquid refrigerant that has flowed from the sixth refrigerant path 113f to the ninth refrigerant path 113i passes through the refrigerant auxiliary evaporator adjustment valve 73.

  In the refrigerant auxiliary evaporator regulating valve 73, the high-pressure liquid refrigerant expands to become a low-pressure gas-liquid two-phase refrigerant, and the low-pressure gas-liquid two-phase refrigerant flows to the refrigerant auxiliary evaporator 72.

  The temperature of the low-pressure gas-liquid two-phase refrigerant flowing to the refrigerant circuit 110 side of the refrigerant auxiliary evaporator 72 is lower than the temperature of engine cooling water flowing to the engine cooling water circuit side (not shown) of the refrigerant auxiliary evaporator 72. For this reason, heat moves from the engine coolant to the low-pressure gas-liquid two-phase refrigerant. As a result, the low-pressure gas-liquid two-phase refrigerant is vaporized by obtaining the evaporation heat, becomes a low-pressure gas refrigerant, and is sent to the tenth refrigerant path 113j. On the other hand, the engine coolant is cooled by the endothermic action of the refrigerant.

  The high-pressure liquid refrigerant that has flowed from the sixth refrigerant path 113f to the twelfth refrigerant path 113l passes through the supercooling heat exchanger adjustment valve 92.

  In the adjustment valve 92 for the supercooling heat exchanger, the high-pressure liquid refrigerant expands to become a low-pressure gas-liquid two-phase refrigerant, and the low-pressure gas-liquid two-phase refrigerant flows to the supercooling heat exchanger 91.

  The temperature of the low-pressure gas-liquid two-phase refrigerant flowing to the twelfth refrigerant path 113l side of the supercooling heat exchanger 91 is lower than the temperature of the high-pressure liquid refrigerant flowing to the sixth refrigerant path 113f side of the supercooling heat exchanger 91. For this reason, heat moves from the high-pressure liquid refrigerant to the low-pressure gas-liquid two-phase refrigerant. As a result, the low-pressure gas-liquid two-phase refrigerant is vaporized by obtaining the evaporation heat, becomes a low-pressure gas refrigerant, and is sent to the refrigerant path closer to the compression unit 10 than the first switching valve 114 of the eleventh refrigerant path 113k. On the other hand, the high-pressure liquid refrigerant flowing to the sixth refrigerant path 113f side of the supercooling heat exchanger 91 is cooled by the endothermic action of the low-pressure gas-liquid two-phase refrigerant.

  Thereafter, in the heat pump 100A, the above-described series of cooling operation is repeated in the same manner.

  As described above, in the heat pump 100A, by appropriately performing the cooling operation, the use-side heat exchange unit 101 (in this example, the indoor unit) can appropriately cool the temperature adjustment target (in this example, indoor air).

-Cooling operation at low outside temperature-
By the way, in heat pump 100A, when performing a cooling operation when the temperature of the air heat-exchanged with the heat source side heat exchanger 20 is too low, there exist the following inconveniences.

  That is, when performing the cooling operation, the temperature of the air (specifically, the outside air) heat-exchanged by the heat source side heat exchanger 20 (specifically, the outdoor heat exchanger) is the refrigerant condensing temperature (specifically, When it is excessively low with respect to 40 ° C. or higher (for example, about 50 ° C.) (specifically, when it is low in the autumn or spring, particularly in winter, it is low to about the outside air temperature (for example, about 10 ° C. or lower)) In FIG. 4, the condensation capacity becomes excessive with respect to the evaporation capacity in the use side heat exchanger 50 (for example, the indoor heat exchanger).

As a result, the condensing pressure is reduced in the engine-driven compressor 11 and / or the electric compressor 12, and the pressure between the refrigerant discharge pressure and the suction pressure of the engine-driven compressor 11 and / or the electric compressor 12 is accordingly increased. The difference is reduced, and in some cases, the rotational speed of the engine-driven compressor 11 and / or the electric compressor 12 has the following three requirements for continuing the operation of the engine-driven compressor 11 and / or the electric compressor 12: Cannot be protected.
(1) Permissible operating range of engine-driven compressor 11 and / or electric compressor 12 (2) Refrigerant high / low pressure difference necessary for refrigerant transfer and, in the case of an oil supply type compressor, required for oil supply to the compressor (3) Refrigerant low pressure to ensure refrigerant evaporating temperature equal to or higher than the freezing temperature of the evaporator In the single operation of the engine driven compressor 11, if the condenser capacity becomes excessive, the engine Although it was possible to maintain the balance of the refrigerating capacity of the condenser and the evaporator by using the refrigerant auxiliary evaporator using the waste heat as a heat source, the engine wasted when the electric compressor 12 was switched to the single operation. This is particularly problematic because the refrigerant auxiliary evaporator 72 using heat as a heat source cannot be used.

  In this regard, in the first embodiment, the control device 120, when performing the cooling operation, has a predetermined temperature at which the temperature of the heat exchanged in the heat source side heat exchanger 20 (specifically, the outside air temperature T) is predetermined. When Ts (for example, about 10 ° C.) or less (T ≦ Ts), the heat source side heat exchanger 20 has a condensing capacity that is smaller than the maximum condensing capacity.

  According to the heat pump 100A according to the first embodiment, when the cooling operation is performed, when the temperature of the air that is heat-exchanged in the heat source side heat exchanger 20 (specifically, the outside air temperature T) is equal to or lower than the predetermined temperature Ts. (T ≦ Ts) Since the condensing capacity of the heat source side heat exchanger 20 is made smaller than the maximum condensing capacity, the condensing capacity in the heat source side heat exchanger 20 becomes excessive with respect to the evaporation capacity in the use side heat exchanger 50. This can prevent the decrease in the condensation pressure in the engine-driven compressor 11 and / or the electric compressor 12, and accordingly, the engine-driven compressor 11 and / or the electric compressor 12. The pressure difference between the refrigerant discharge pressure and the suction pressure can be increased, and as a result, the rotational speed of the engine-driven compressor 11 and / or the electric compressor 12 can be increased. Can. As a result, the above three requirements for the rotational speed of the engine-driven compressor 11 and / or the electric compressor 12 can be ensured, and therefore the operation of the engine-driven compressor 11 and / or the electric compressor 12 can be ensured. Can continue. This is particularly effective because the refrigerant auxiliary evaporator 72 using the engine waste heat as a heat source cannot be used when the electric compressor 12 is switched to the single operation.

  Specifically, the heat source side heat exchanger 20 is configured by a plurality of units [in this example, a plurality of heat source side heat exchanger units 20 (1) to 20 (n)], and the control device 120 performs the cooling operation. When the temperature (specifically, the outside air temperature T) of the heat exchanged in the heat source side heat exchanger units 20 (1) to 20 (n) is equal to or lower than the predetermined temperature Ts (T ≦ Ts), the heat source side heat The on-off valve 21 is controlled so that the condensation capacity of the exchanger 20 [heat source side heat exchanger units 20 (1) to 20 (n)] is smaller than the maximum condensation capacity [in this example, n and i are 2 And closes the on-off valve 21 corresponding to the heat source side heat exchanger unit 20 (2).

  As described above, the heat source side heat exchanger 20 is configured by a plurality of units [a plurality of heat source side heat exchanger units 20 (1) to 20 (n)], so that a heat source configured by a plurality of units in an existing heat pump. The side heat exchanger can be used, and the condensing capacity of the heat source side heat exchanger 20 can be changed among the upstream branch paths of the heat source side heat exchanger units 20 (1) to 20 (n). Thus, it can be realized with a simple configuration in which the on-off valve 21 is provided in at least one branch path.

  Specifically, the heat pump 100A further includes an air temperature sensor 164 that detects the temperature of air that is heat-exchanged by the heat source side heat exchanger 20 (specifically, the outside air temperature T). The temperature sensor 164 is a thermistor in this example.

  Specifically, the air temperature sensor 164 is provided in the vicinity of the heat source side heat exchanger 20 and detects the ambient temperature around the heat source side heat exchanger 20. Thereby, the air temperature sensor 164 can detect the temperature of air that is heat-exchanged by the heat source side heat exchanger 20 (specifically, the outside air temperature T). Here, the predetermined temperature Ts is stored (set) in the storage unit 122 in advance.

(Control example of the first embodiment)
FIG. 3 is a flowchart showing an example of a control operation performed during the cooling operation by the control device 120 in the heat pump 100A shown in FIG.

  In the control operation of the heat pump 100A shown in FIG. 3, first, the control device 120 determines whether or not it is a cooling operation instruction (step S11), and when it is not a cooling operation instruction (step S11: No), On the other hand, if the instruction is for cooling operation (Yes in step S11), the process proceeds to step S12.

  Next, the control device 120 determines whether or not the outside air temperature T detected by the temperature sensor 164 is equal to or lower than a predetermined temperature Ts (for example, about 10 ° C.) stored in advance in the storage unit 122 (step S12).

  Next, when the control device 120 determines that the outside air temperature T is equal to or lower than the predetermined temperature Ts (step S12: Yes), the heat source side heat exchanger 20 [heat source side heat exchanger 20] At least one of the on-off valves 21 [in this example, n and i are 2 so that the condensing capacity of the units 20 (1) to 20 (n)] is reduced, and the heat source side heat exchanger unit 20 (2) The on-off valve 21] corresponding to is closed to make the condensation capacity of the heat source side heat exchanger 20 smaller than the maximum condensation capacity (step S13). Then, the control device 120 converts the condensation capability of the heat source side heat exchanger 20 [heat source side heat exchanger units 20 (1) to 20 (n)] into a condensation capability [in this example, n, i Is 2, and the cooling operation is performed with the minimum condensing capacity of only the heat source side heat exchanger unit 20 (1) of the heat source side heat exchanger units 20 (1) and 20 (2) (step S14).

  On the other hand, when the control device 120 determines that the outside air temperature T is higher than the predetermined temperature Ts (step S12: No), the heat source side heat exchanger 20 [heat source side heat exchanger unit increases as the outside air temperature T increases. 20 (1) to 20 (n)] at least one of the on-off valves 21 [in this example, n and i are 2 and the heat source side heat exchanger unit 20 (2) The corresponding on-off valve 21] is opened to make the condensation capacity of the heat source side heat exchanger 20 larger than the minimum condensation capacity (step S15). Then, the control device 120 sets the condensing capacity of the heat source side heat exchanger 20 [heat source side heat exchanger units 20 (1) to 20 (n)] according to the outside air temperature T [in this example, n is 2]. The maximum cooling capacity of the heat source side heat exchanger units 20 (1) and 20 (2)] is performed to perform the cooling operation (step S14).

  And the control apparatus 120 repeats a series of operation | movement of above described step S11-S14.

(Heating operation)
Next, the operation of the heating operation by the heat pump 100A according to the first embodiment will be described below with reference to FIG.

  FIG. 4 is a schematic block diagram showing a heating operation state in which a heating operation is performed in the heat pump 100A shown in FIG. In FIG. 4, a thick line indicates the flow of the refrigerant. The same applies to FIG. 9 described later.

  In the example shown in FIG. 4, in the heating operation, the control device 120 adjusts the opening degrees of the first adjustment valves 41 (1) to 41 (n) and the refrigerant auxiliary evaporator adjustment valve 73 and fully opens the second adjustment valve 42. The supercooling heat exchanger adjustment valve 92 is fully closed, and the first switching valve 114 and the on-off valve 21 are opened.

  In the heat pump 100A, when performing the heating operation, the control device 120 switches the four-way valve 111 to the second connection state to connect the first refrigerant path 113a and the eighth refrigerant path 113h, and to connect the third refrigerant path 113c and the second refrigerant path 113c. The refrigerant path 113b is communicated. By doing so, the high-pressure gas refrigerant discharged from the compressor 10 (in this example, the engine-driven compressor 11 and the electric compressor 12) flows from the oil separator 81 of the first refrigerant path 113a to the four-way valve 111, the eighth refrigerant path. It flows to the use side heat exchanger 50 via 113h and the other connecting pipe 110b.

  The temperature of the high-pressure gas refrigerant flowing to the refrigerant circuit 110 side of the use side heat exchanger 50 is higher than the temperature of the temperature adjustment target side (in this example, the indoor air side) of the use side heat exchanger 50. For this reason, heat moves from the high-pressure gas refrigerant to the temperature adjustment target side (in this example, the indoor air side). As a result, the high pressure gas refrigerant loses heat of condensation and liquefies to become a high pressure liquid refrigerant. On the other hand, the temperature adjustment target side (in this example, the indoor air side) is heated by the heat radiation action of the refrigerant. That is, in the heating operation, the use-side heat exchanger 50 functions as a heater for a temperature adjustment target (in this example, indoor air) radiated by the high-pressure gas refrigerant.

  The high-pressure liquid refrigerant flows from the use side heat exchanger 50 to the second intermediate connection point P3 of the bridge circuit 112 via the second adjustment valve 42, the one connection pipe 110a, and the seventh refrigerant path 113g. Since the second intermediate connection point P3 is located on the inlet side of the third check valve 112c and on the outlet side of the fourth check valve 112d, the high-pressure liquid refrigerant is supplied from the first check valve 112a and the fourth check valve 112a. It does not flow toward the check valve 112d, and passes through the third check valve 112c and the outflow connection point P2 from the second intermediate connection point P3 to the receiver 71 and the sixth refrigerant route 113f from the fifth refrigerant path 113e. It flows to the inflow connection point P4 of the bridge circuit 112 via the cooling heat exchanger 91. The inflow connection point P4 is on the inflow side of the second check valve 112b and the fourth check valve 112d, but the high-pressure liquid refrigerant described above flows to the second intermediate connection point P3 and the outflow connection point P2 side. Therefore, the high-pressure liquid refrigerant does not flow toward the first check valve 112a and the fourth check valve 112d due to a pressure difference from the high-pressure liquid refrigerant flowing to the second intermediate connection point P3 and the outflow connection point P2. The inflow connection point P4 passes through the first check valves 41 (1) to 41 (n) via the second check valve 112b and the first intermediate connection point P1.

  In the first regulating valves 41 (1) to 41 (n), the high-pressure liquid refrigerant expands to become a low-pressure gas-liquid two-phase refrigerant, and the low-pressure gas-liquid two-phase refrigerant passes through the fourth refrigerant paths 113d to 113d. The heat source side heat exchanger units 20 (1) to 20 (n) flow.

  The temperature of the low-pressure gas-liquid two-phase refrigerant flowing through the heat source side heat exchanger units 20 (1) to 20 (n) is the air flowing through the heat source side heat exchanger units 20 (1) to 20 (n) (specifically, Is lower than the temperature of outside air). For this reason, heat moves from air (specifically, outside air) to the low-pressure gas-liquid two-phase refrigerant. As a result, the low-pressure gas-liquid two-phase refrigerant is vaporized by obtaining the evaporation heat, and becomes a low-pressure gas refrigerant. That is, in the heating operation, the heat source side heat exchanger units 20 (1) to 20 (n) function as a refrigerant evaporator that absorbs heat from the low-pressure gas-liquid two-phase refrigerant.

  Thereafter, the low-pressure gas refrigerant flows from the heat source side heat exchanger units 20 (1) to 20 (n) to the third refrigerant path 113c. At this time, since the control device 120 communicates the third refrigerant path 113c and the second refrigerant path 113b by the four-way valve 111, the low-pressure gas refrigerant is supplied to the accumulator 82 and the first switching on the second refrigerant path 113b. The air is sucked into the compression unit 10 via the valve 114.

  The high-pressure liquid refrigerant that has flowed from the sixth refrigerant path 113f to the ninth refrigerant path 113i passes through the refrigerant auxiliary evaporator adjustment valve 73.

  In the refrigerant auxiliary evaporator regulating valve 73, the high-pressure liquid refrigerant expands to become a low-pressure gas-liquid two-phase refrigerant, and the low-pressure gas-liquid two-phase refrigerant flows to the refrigerant auxiliary evaporator 72.

  The temperature of the low-pressure gas-liquid two-phase refrigerant flowing to the refrigerant circuit 110 side of the refrigerant auxiliary evaporator 72 is lower than the temperature of engine cooling water flowing to the engine cooling water circuit side (not shown) of the refrigerant auxiliary evaporator 72. For this reason, heat moves from the engine coolant to the low-pressure gas-liquid two-phase refrigerant. As a result, the low-pressure gas-liquid two-phase refrigerant is vaporized by obtaining the evaporation heat, becomes a low-pressure gas refrigerant, and is sent to the tenth refrigerant path 113j. On the other hand, the engine coolant is cooled by the endothermic action of the refrigerant.

  Thereafter, in the heat pump 100A, the above-described series of heating operation is repeated in the same manner.

  As described above, in the heat pump 100A, by appropriately performing the heating operation, the temperature adjustment target (air in the room in this example) can be appropriately heated by the use side heat exchange unit 101 (in this example, the indoor unit).

Second Embodiment
FIG. 5 is a schematic block diagram of an example of a heat pump 100B according to the second embodiment.

  The heat pump 100B shown in FIG. 5 is similar to the heat pump 100A shown in FIG. 1 except that the on-off valve 21, the refrigerant auxiliary evaporator 72, the refrigerant auxiliary evaporator regulating valve 73, the ninth refrigerant path 113i, the tenth refrigerant path 113j, and the check valve 40a. The switching valve 22, the third adjustment valve 43, the auxiliary heat exchanger 74, the engine coolant temperature sensor 165, the refrigerant condensing temperature sensor 166, the thirteenth refrigerant path 113m, the fourteenth refrigerant path 113n, and the second switching valve 115 and a check valve 116 are provided.

  In the heat pump 100B illustrated in FIG. 5, members having substantially the same configuration as the heat pump 100A illustrated in FIG. 1 are denoted by the same reference numerals, and different points will be mainly described below.

  The heat pump 100B is a heat source side heat exchanger 20 that exchanges heat between refrigerant and air (specifically, outside air), and auxiliary heat exchange that exchanges heat between the refrigerant and engine cooling water that cools the engine 61. A container 74 is provided. The heat source side heat exchanger 20 and the auxiliary heat exchanger 74 constitute a heat source side heat exchanger section 200.

  The heat source side heat exchanger 20 may be a single heat source side heat exchanger or a plurality of heat source side heat exchangers connected in parallel.

  The regulating valve 40 functions as an expansion valve, and in this example, includes a first regulating valve 41 that can be closed, a second regulating valve 42 that can be closed, and a third regulating valve 43 that can be closed. The first adjustment valve 41 may be a plurality of adjustment valves connected in parallel.

  The third refrigerant path 113 c connects the other connection port 111 d of the four-way valve 111 to one connection port 20 a of the heat source side heat exchanger 20 and one connection port 74 a of the auxiliary heat exchanger 74. The fourth refrigerant path 113d connects the other connection port 20b of the heat source side heat exchanger 20 and the first intermediate connection point P1 of the bridge circuit 112. The thirteenth refrigerant path 113m connects the other connection port 74b of the auxiliary heat exchanger 74 and the first intermediate connection point P1 of the bridge circuit 112.

  The auxiliary heat exchanger 74 is a branch path branched on the upstream side of the heat source side heat exchanger 20 in the flow direction W of the discharge gas refrigerant (high pressure gas refrigerant) discharged from the engine driven compressor 11 and / or the electric compressor 12. (In this example, it is provided in the branch path of the third refrigerant path 113c).

  The first regulating valve 41 and the third regulating valve 43 that constitute the regulating valve 40 are provided in the fourth refrigerant path 113d and the thirteenth refrigerant path 113m, respectively, and the opening degree is adjusted during the heating operation, whereby the flow rate of the refrigerant is adjusted. To control.

  The heat pump 100B shown in FIG. 5 further includes a second switching valve 115 and a check valve 116, and the refrigerant circuit 110 further includes a fourteenth refrigerant path 113n.

  The fourteenth refrigerant path 113n connects the refrigerant path closer to the heat source side heat exchanger 20 than the first adjustment valve 41 of the fourth refrigerant path 113d and the outflow connection point P2 of the bridge circuit 112. The second switching valve 115 and the check valve 116 are provided in the fourteenth refrigerant path 113n. The second switching valve 115 switches between a circulation state in which the refrigerant is circulated in the fourteenth refrigerant path 113n and an interruption state in which the refrigerant is blocked by an opening / closing operation. The check valve 116 allows the refrigerant to flow from the second switching valve 115 to the outflow connection point P2 of the bridge circuit 112, while blocking the refrigerant flow from the outflow connection point P2 of the bridge circuit 112 to the second switching valve 115.

  The heat pump 100B further includes a switching valve 22. Whether the switching valve 22 and the third adjustment valve 43 supply the heat source side heat exchanger 20 with the flow direction W of the discharge gas refrigerant (high-pressure gas refrigerant) discharged from the engine-driven compressor 11 and / or the electric compressor 12. Alternatively, the supply to the auxiliary heat exchanger 74 is switched.

  In this example, the switching valve 22 (specifically, an on-off valve) is provided in a branch path to the auxiliary heat exchanger 74 in the third refrigerant path 113c.

  The switching valve 22 is configured to switch between a closed state and an open state according to an instruction signal from the control device 120. Therefore, the control device 120 can supply the refrigerant to the heat source side heat exchanger 20 or supply the refrigerant to the auxiliary heat exchanger 74 by controlling the operation of the switching valve 22 and the third adjustment valve 43.

  Specifically, when the control device 120 opens the switching valve 22 and closes the third adjustment valve 43, the refrigerant is supplied to the heat source side heat exchanger 20. On the other hand, when the control device 120 closes the switching valve 22 and opens the third adjustment valve 43, the refrigerant is supplied to the auxiliary heat exchanger 74. In this case, the switching valve 22 may have a function of an adjustment valve that adjusts the flow rate of the refrigerant.

  Note that a switching valve 22 (specifically, an on-off valve) is provided on both the branch path to the heat source side heat exchanger 20 and the branch path to the auxiliary heat exchanger 74 in the third refrigerant path 113c, and the control device 120 The switching valve 22 may be operated and controlled. In this case, when the control device 120 opens the switching valve 22 in the branch path to the heat source side heat exchanger 20 and closes the switching valve 22 in the branch path to the auxiliary heat exchanger 74, the heat source side heat exchanger 20. Is supplied with refrigerant. On the other hand, when the control device 120 closes the switching valve 22 in the branch path to the heat source side heat exchanger 20 and opens the switching valve 22 in the branch path to the auxiliary heat exchanger 74, the control device 120 causes the auxiliary heat exchanger 74 to supply refrigerant. Is supplied. Also in this case, the switching valve 22 may have a function of an adjusting valve for adjusting the flow rate of the refrigerant.

  Further, a branch path to the heat source side heat exchanger 20 and a branch path to the auxiliary heat exchanger 74 are selectively selected at the branch point Q of the heat source side heat exchanger 20 and the auxiliary heat exchanger 74 in the third refrigerant path 113c. You may provide the switching valve switched to. In this case, when the control device 120 switches the switching valve to the branch path to the heat source side heat exchanger 20, the refrigerant is supplied to the heat source side heat exchanger 20. On the other hand, when the control device 120 switches to the branch path to the auxiliary heat exchanger 74, the refrigerant is supplied to the auxiliary heat exchanger 74. Also in this case, the switching valve may have a function of an adjusting valve that adjusts the flow rate of the refrigerant.

(Cooling operation)
Next, the operation of the cooling operation by the heat pump 100B according to the second embodiment will be described below with reference to FIGS.

  FIG. 6 is a schematic block diagram illustrating a cooling operation state in which the cooling operation is performed in the heat pump 100B illustrated in FIG.

  In the example illustrated in FIG. 6, in the cooling operation, the control device 120 fully closes the first adjustment valve 41, adjusts the opening of the second adjustment valve 42 and the subcooling heat exchanger adjustment valve 92, and sets the third adjustment valve. 43 is fully open or fully closed, the switching valve 22 is opened or closed, and the first switching valve 114 and the second switching valve 115 are opened.

  In the heat pump 100B, when performing the cooling operation, the control device 120 switches the four-way valve 111 to the first connection state so as to communicate the first refrigerant path 113a and the third refrigerant path 113c, and the eighth refrigerant path 113h and the second refrigerant path 113h. The refrigerant path 113b is communicated. By doing so, the high-pressure gas refrigerant discharged from the compressor 10 (in this example, the engine-driven compressor 11 and the electric compressor 12) is transferred from the oil separator 81 of the first refrigerant path 113a to the four-way valve 111 and the third refrigerant path. It flows to the heat source side heat exchanger section 200 via 113c.

  Specifically, when the switching valve 22 is opened and the third adjustment valve 43 is fully closed, the high-pressure gas refrigerant is only the heat source side heat exchanger 20 of the heat source side heat exchanger 20 and the auxiliary heat exchanger 74. When the switching valve 22 is closed and the third regulating valve 43 is fully opened, the high-pressure gas refrigerant is the auxiliary heat exchanger of the heat source side heat exchanger 20 and the auxiliary heat exchanger 74. It flows only to 74 (see thick broken line). The opening / closing operation of the switching valve 22 will be described in detail later.

  The temperature of the high-pressure gas refrigerant flowing through the heat source side heat exchanger 20 is higher than the temperature of air (specifically, outside air) heat exchanged by the heat source side heat exchanger 20. For this reason, heat moves from the high-pressure gas refrigerant to the air (specifically, outside air). As a result, the high-pressure gas refrigerant loses heat of condensation and liquefies to become a high-pressure liquid refrigerant (hereinafter referred to as high-pressure liquid refrigerant). That is, in the cooling operation, the heat source side heat exchanger 20 functions as a refrigerant condenser that dissipates heat from the high-pressure gas refrigerant. The operation of the auxiliary heat exchanger 74 will be described later.

  The high pressure liquid refrigerant passes through the fourth refrigerant path 113d from the heat source side heat exchanger 20, the second switching valve 115 and the check valve 116 in the fourteenth refrigerant path 113n, or from the auxiliary heat exchanger 74 to the thirteenth refrigerant path. After passing through the 113 m third regulating valve 43, the first intermediate connection point P1, the first check valve 112a and the outflow connection point P2, the supercooling heat exchanger of the fifth refrigerant path 113e, the receiver 71, and the sixth refrigerant path 113f It flows to the inflow connection point P4 of the bridge circuit 112 via 91. As described above, the high-pressure liquid refrigerant does not flow toward the second check valve 112b and the third check valve 112c, but from the inflow connection point P4 to the fourth check valve 112d, the second intermediate connection point P3, It passes through the second adjustment valve 42 via the seven refrigerant paths 113g and the one connecting pipe 110a.

  The following operation is the same as that of the heat pump 100A according to the first embodiment except that the refrigerant auxiliary evaporator 72 and the refrigerant auxiliary evaporator adjustment valve 73 are removed, and the description thereof is omitted here.

-Cooling operation at low outside temperature-
By the way, the temperature of the air (specifically, the outside air) heat-exchanged by the heat source side heat exchanger 20 (specifically, the outdoor heat exchanger) is the refrigerant condensing temperature (specifically, 40 ° C. or more, for example, 50 ° C.). If the temperature is excessively low (specifically, when the temperature is low in the autumn or spring, especially in the winter, such as low outside air temperature (for example, about 10 ° C. or less)), the engine cooling water has a larger specific heat than air. From the viewpoint of being housed in the engine coolant circuit 300, the temperature is usually higher than the air (specifically, outside air) heat-exchanged by the heat source side heat exchanger 20 (specifically, the outdoor heat exchanger). It has become. Further, the engine cooling water in a state where the engine 61 is stopped is usually a temperature (for example, about 20 ° C.) lower than the refrigerant condensing temperature except immediately after the operation of the engine 61 is stopped.

  From this point of view, in the second embodiment, when performing the cooling operation, the control device 120 has a predetermined temperature (specifically, the outside air temperature T) in which heat is exchanged in the heat source side heat exchanger 20. When the temperature is equal to or lower than the temperature Ts (for example, about 10 ° C.) (T ≦ Ts), the engine cooling water temperature Tw that is the temperature of the engine cooling water is stopped in the heat source side heat exchanger 20 while the engine 61 is stopped. Flow direction of the discharge gas refrigerant (high pressure gas refrigerant) discharged from the engine driven compressor 11 and / or the electric compressor 12 when the temperature is higher than the air temperature (specifically, the outside air temperature T) (Tw> T). W is configured to go to the auxiliary heat exchanger 74 (in this example, only the auxiliary heat exchanger 74 out of the heat source side heat exchanger 20 and the auxiliary heat exchanger 74 is set).

  In the heat pump 100B of the aspect according to the second embodiment, the temperature (for example, about 50 ° C.) of the high-pressure gas refrigerant flowing in the auxiliary heat exchanger 74 during the cooling operation is the engine coolant temperature Tw that is heat-exchanged by the auxiliary heat exchanger 74. (For example, about 20 ° C.). For this reason, heat moves from the high-pressure gas refrigerant to the engine coolant. As a result, the high pressure gas refrigerant loses heat of condensation and liquefies to become a high pressure liquid refrigerant. That is, in the cooling operation, the auxiliary heat exchanger 74 functions as a refrigerant condenser that dissipates heat from the high-pressure gas refrigerant.

  According to the heat pump 100B of the aspect according to the second embodiment, when performing the cooling operation, the temperature of the air that is heat-exchanged in the heat source side heat exchanger 20 (specifically, the outside air temperature T) is a predetermined temperature Ts (for example, When the temperature is below (T ≦ Ts), the temperature of the air (specifically, the engine 61 is stopped and the engine cooling water temperature Tw (for example, about 20 ° C.) is heat-exchanged by the heat source side heat exchanger 20. Specifically, when the temperature is higher than the outside air temperature T) (Tw> T), the flow direction W of the discharge gas refrigerant (high-pressure gas refrigerant) discharged from the engine-driven compressor 11 and / or the electric compressor 12 is auxiliary heat exchange. Therefore, the engine coolant that is higher in temperature than the air (specifically, outside air) that is heat-exchanged in the heat source side heat exchanger 20 and lower in temperature than the condensation temperature of the refrigerant is used. Cool the refrigerant Can. Then, since the temperature of the engine coolant that is heat-exchanged in the auxiliary heat exchanger 74 does not become excessively low with respect to the refrigerant condensing temperature, the condensation capacity in the auxiliary heat exchanger 74 evaporates in the use-side heat exchanger 50. It is possible not to become excessive with respect to the capacity. As a result, a decrease in the condensation pressure in the engine-driven compressor 11 and / or the electric compressor 12 can be suppressed, and accordingly, the refrigerant discharge pressure and the suction pressure of the engine-driven compressor 11 and / or the electric compressor 12 can be reduced. Of the engine drive compressor 11 and / or the electric compressor 12 can be increased. As a result, the above three requirements for the rotational speed of the engine-driven compressor 11 and / or the electric compressor 12 can be ensured, and therefore the operation of the engine-driven compressor 11 and / or the electric compressor 12 can be ensured. Can continue. This is particularly effective because the refrigerant auxiliary evaporator 72 using the engine waste heat as a heat source cannot be used when the electric compressor 12 is switched to the single operation.

  Specifically, the control device 120, when performing the cooling operation, when the temperature (specifically, the outside air temperature T) of the heat exchanged by the heat source side heat exchanger 20 is equal to or lower than a predetermined temperature Ts (T ≦ Ts). ), When the engine coolant temperature Tw when the engine 61 is stopped is higher than the temperature of air that is heat-exchanged in the heat source side heat exchanger 20 (specifically, the outside air temperature T) (T <Tw), and When the refrigerant condensing temperature is lower than the refrigerant condensing temperature Tc (Tw <Tc), the discharge gas refrigerant (high pressure gas refrigerant) discharged from the engine driven compressor 11 and / or the electric compressor 12 is an auxiliary heat exchanger. The switching valve 22 and the third adjustment valve 43 are controlled so as to flow to 74 (in this example, the switching valve 22 is closed and the third adjustment valve 43 is fully opened).

  By doing so, the discharged gas refrigerant (high-pressure gas refrigerant) discharged from the engine-driven compressor 11 and / or the electric compressor 12 can be reliably flowed toward the auxiliary heat exchanger 74.

  Specifically, the heat pump 100B further includes an engine coolant temperature sensor 165 that detects the engine coolant temperature Tw, and a refrigerant condensation temperature sensor 166 that detects the refrigerant condensation temperature Tc. The engine coolant temperature sensor 165 and the refrigerant condensing temperature sensor 166 are thermistors in this example.

  Specifically, the engine coolant temperature sensor 165 is provided in the coolant passage 300a (see FIG. 8) of the engine coolant circuit 300 (not shown in FIG. 5, see FIG. 8 described later), and the coolant passage 300a. Detect the temperature of Thereby, the engine coolant temperature sensor 165 can detect the engine coolant temperature Tw.

  The refrigerant condensing temperature sensor 166 is provided in the first refrigerant path 113a and detects the temperature of the first refrigerant path 113a. Thereby, the refrigerant condensing temperature sensor 166 can detect the engine coolant temperature Tw. Note that a predetermined refrigerant condensing temperature Tc that is predetermined as the refrigerant condensing temperature Tc may be stored (set) in the storage unit 122 in advance without detecting the refrigerant condensing temperature Tc.

(Control example of the second embodiment)
FIG. 7 is a flowchart illustrating an example of a control operation performed during the cooling operation by the control device 120 in the heat pump 100B illustrated in FIG.

  In the control operation of the heat pump 100B shown in FIG. 5, first, the control device 120 determines whether or not it is a cooling operation instruction (step S21), and when it is not a cooling operation instruction (step S21: No), On the other hand, if the instruction is for cooling operation (Yes in step S21), the process proceeds to step S22.

  Next, the control device 120 determines whether or not the outside air temperature T detected by the temperature sensor 164 is equal to or lower than a predetermined temperature Ts (for example, about 10 ° C.) stored in advance in the storage unit 122 (step S22).

  Next, when it is determined that the outside air temperature T is equal to or lower than the predetermined temperature Ts (step S22: Yes), the control device 120 determines whether or not the engine 61 is stopped (step S23).

  Next, when the control device 120 determines that the engine 61 is stopped (step S23: Yes), the outside air detected by the air temperature sensor 164 is the engine coolant temperature Tw detected by the engine coolant temperature sensor 165. It is determined whether or not the temperature is higher than T (step S24).

  Next, when the control device 120 determines that the engine coolant temperature Tw is higher than the outside air temperature T (step S24: Yes), the coolant concentration temperature detected by the coolant condensation temperature sensor 166 is detected by the coolant temperature Tw. It is determined whether it is lower than Tc (step S25).

  Next, when determining that the engine coolant temperature Tw is lower than the refrigerant condensing temperature Tc (step S25: Yes), the control device 120 closes the switching valve 22 and fully opens the third adjustment valve 43. Then, the high-pressure gas refrigerant is passed through the auxiliary heat exchanger 74 (step S26). And the control apparatus 120 cools a high pressure gas refrigerant | coolant with engine cooling water, and performs cooling operation (step S28).

  On the other hand, the control device 120 determines that the outside air temperature T is higher than the predetermined temperature Ts (step S22: No), and determines that the engine 61 is in operation (step S23: No), the engine cooling water temperature Tw. Is determined to be equal to or lower than the outside air temperature T (step S24: No), or when it is determined that the engine coolant temperature Tw is equal to or higher than the refrigerant condensing temperature Tc (step S25: No), the switching valve 22 is turned on. The third adjustment valve 43 is fully closed and the high pressure gas refrigerant is allowed to flow to the heat source side heat exchanger 20 (step S27). And the control apparatus 120 cools a high pressure gas refrigerant | coolant with external air, and performs cooling operation (step S28).

  And the control apparatus 120 repeats a series of operation | movement of above-described step S21-S28.

  By the way, the heat of the engine cooling water moves from the high-pressure gas refrigerant to the engine cooling water, so that the temperature rises and the cooling effect of the high-pressure gas refrigerant decreases. For this reason, it is necessary to lower the engine coolant temperature Tw.

  In this regard, the heat pump 100B shown in FIG. 5 has the following configuration for reducing the engine coolant temperature Tw.

  FIG. 8 is a schematic block diagram showing a configuration in which heat is dissipated from the engine coolant when the engine coolant temperature Tw becomes equal to or higher than a predetermined upper limit temperature Th in the heat pump 100B shown in FIG. In FIG. 8, the arrow indicates the flow direction of the engine cooling water.

  As shown in FIG. 8, the heat pump 100 </ b> B includes an engine coolant circuit 300. In addition, the broken line has shown the flow of the engine cooling water after a branch.

  When the engine coolant temperature Tw becomes equal to or higher than a predetermined upper limit temperature Th (Tw ≧ Th), the engine coolant circuit 300 performs a heat radiation operation to dissipate the engine coolant, and the engine coolant temperature Tw becomes the predetermined upper limit temperature Th. Below (Tw <Th), the heat dissipation operation is canceled.

  Specifically, the engine coolant circuit 300 includes a coolant circulation path 301 and a coolant bypass path 302.

  The cooling water circulation path 301 includes an engine 61, an exhaust gas heat exchanger 310 that exchanges heat between exhaust gas discharged from the engine 61 and engine cooling water that flows out of the engine 61, and a radiator that radiates the engine cooling water. 320 and a cooling water pump 330 that circulates the engine cooling water in the cooling water circulation path 301 is provided. Thus, the engine coolant from the discharge side of the coolant pump 330 can be returned to the suction side of the coolant pump 330 via the exhaust gas heat exchanger 310, the engine 61, and the radiator 320, and the engine coolant can be circulated.

  Further, the cooling water bypass path 302 bypasses in the middle of the cooling water circulation path 301. Thereby, engine cooling water can be circulated in the middle of the cooling water circulation path 301. An auxiliary heat exchanger 74 is provided in the cooling water bypass path 302. The engine coolant circuit 300 further includes a thermostat type switching valve 340. A thermostat type switching valve 340 is provided at a branch portion between the cooling water circulation path 301 and the cooling water bypass path 302.

  The thermostat type switching valve 340 has an inflow port 341 for flowing in engine cooling water from the cooling water circulation path 301 and two outflow ports 342 and 343 for flowing out engine cooling water from the inflow port 341. The inlet 341 and the outlet 342 are connected to the cooling water circulation path 301, and the other outlet 343 is connected to the cooling water bypass path 302.

  The thermostat type switching valve 340 operates to flow from the inlet 341 to both the outlets 342 and 343 when the engine cooling water is equal to or higher than the predetermined upper limit temperature Th (Tw ≧ Th), while the engine cooling water is predetermined. When the temperature is lower than the upper limit temperature Th (Tw <Th), it is configured to operate so as to flow only from the inlet 341 to the other outlet 343. As a result, the engine coolant circuit 300 performs a heat dissipating operation for dissipating the engine coolant with the radiator 320 when the engine coolant reaches a predetermined upper limit temperature Th, and performs a heat dissipating operation when the engine coolant falls below the predetermined upper limit temperature Th. Can be released. Here, the thermostat type switching valve 340 can adjust the ratio of the outflow amount of engine cooling water flowing from the inflow port 341 to both the outflow ports 342 and 343.

  The engine coolant circuit 300 further includes a filter 350 that removes foreign matters contained in the engine coolant. In this example, the filter 350 is provided between the engine 61 and the thermostat type switching valve 340.

(Heating operation)
In the heat pump 100B according to the second embodiment, the auxiliary heat exchanger 74 that acts as a condenser during the cooling operation is used as an evaporator during the heating operation.

  By doing so, the auxiliary heat exchanger 74 acting as a condenser during the cooling operation can be used as a refrigerant auxiliary evaporator (sub-evaporator) used as an evaporator during the heating operation as used in the first embodiment. it can. As a result, the condenser acting during the cooling operation and the evaporator used during the heating operation can be shared by the auxiliary heat exchanger 74. Therefore, even if an auxiliary heat exchanger (sub-evaporator) used as an evaporator during heating operation is used, there is no need to separately provide a refrigerant auxiliary evaporator (sub-evaporator), and the heat pump configuration can be simplified accordingly. it can.

  Next, the operation of the heating operation by the heat pump 100B according to the second embodiment will be described below with reference to FIG.

  FIG. 9 is a schematic block diagram illustrating a heating operation state in which a heating operation is performed in the heat pump 100B illustrated in FIG.

  In the example shown in FIG. 9, in the heating operation, the control device 120 adjusts the opening of the first adjustment valve 41 and the third adjustment valve 43, fully opens the second adjustment valve 42, and the adjustment valve 92 for the supercooling heat exchanger. Is fully closed, and the first switching valve 114 and the switching valve 22 are opened.

  In the heat pump 100B, when performing the heating operation, the control device 120 switches the four-way valve 111 to the second connection state to connect the first refrigerant path 113a and the eighth refrigerant path 113h, and to connect the third refrigerant path 113c and the second refrigerant path 113c. The refrigerant path 113b is communicated. By doing so, the high-pressure gas refrigerant discharged from the compressor 10 (in this example, the engine-driven compressor 11 and the electric compressor 12) flows from the oil separator 81 of the first refrigerant path 113a to the four-way valve 111, the eighth refrigerant path. It flows to the use side heat exchanger 50 via 113h and the other connecting pipe 110b.

  The effect | action by the utilization side heat exchanger 50 is the same as that of the heat pump 100A which concerns on 1st Embodiment, and abbreviate | omits description here.

  The high-pressure liquid refrigerant flows from the use side heat exchanger 50 to the second intermediate connection point P3 of the bridge circuit 112 via the second adjustment valve 42, the one connection pipe 110a, and the seventh refrigerant path 113g. As described above, the high-pressure liquid refrigerant does not flow toward the first check valve 112a and the fourth check valve 112d, and passes from the second intermediate connection point P3 to the third check valve 112c and the outflow connection point P2. Then, it flows from the fifth refrigerant path 113e to the inflow connection point P4 of the bridge circuit 112 via the receiver 71 and the supercooling heat exchanger 91 of the sixth refrigerant path 113f. As described above, the high-pressure liquid refrigerant flows toward the first check valve 112a and the fourth check valve 112d due to a pressure difference from the high-pressure liquid refrigerant flowing through the second intermediate connection point P3 and the outflow connection point P2. Instead, the first adjustment valve 41 and the third adjustment valve 43 are passed from the inflow connection point P4 via the second check valve 112b and the first intermediate connection point P1.

  In the first adjustment valve 41 and the third adjustment valve 43, the high-pressure liquid refrigerant expands to become a low-pressure gas-liquid two-phase refrigerant, and the low-pressure gas-liquid two-phase refrigerant passes through the fourth refrigerant path 113d and the thirteenth refrigerant path 113m. Then, it flows to the heat source side heat exchanger 20 and the auxiliary heat exchanger 74.

  The temperature of the low-pressure gas-liquid two-phase refrigerant flowing through the heat source side heat exchanger 20 is lower than the temperature of the air (specifically outside air) flowing through the heat source side heat exchanger 20. For this reason, heat moves from air (specifically, outside air) to the low-pressure gas-liquid two-phase refrigerant. Further, the temperature of the low-pressure gas-liquid two-phase refrigerant flowing to the refrigerant circuit 110 side of the auxiliary heat exchanger 74 is lower than the temperature of the engine cooling water flowing to the engine cooling water circuit 300 side of the auxiliary heat exchanger 74. For this reason, heat moves from the engine coolant to the low-pressure gas-liquid two-phase refrigerant. As a result, the low-pressure gas-liquid two-phase refrigerant is vaporized by obtaining the evaporation heat, and becomes a low-pressure gas refrigerant. That is, in the heating operation, the heat source side heat exchanger 20 and the auxiliary heat exchanger 74 function as a refrigerant evaporator that absorbs heat from the low-pressure gas-liquid two-phase refrigerant.

  The following operation is the same as that of the heat pump 100A according to the first embodiment except that the refrigerant auxiliary evaporator 72 and the refrigerant auxiliary evaporator adjustment valve 73 are removed, and the description thereof is omitted here.

  In the heat pump 100B according to the second embodiment, the refrigerant auxiliary evaporator 72 and the refrigerant auxiliary evaporator adjustment valve 73 used in the heat pump 100A according to the first embodiment are removed, but the refrigerant auxiliary evaporator 72 and the refrigerant auxiliary are used. You may make it leave the adjustment valve 73 for evaporators.

  The present invention is not limited to the embodiment described above, and can be implemented in various other forms. Therefore, such an embodiment is merely an example in all respects and should not be interpreted in a limited manner. The scope of the present invention is shown by the scope of claims, and is not restricted by the text of the specification. Further, all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

DESCRIPTION OF SYMBOLS 10 Compression part 11 Engine drive compressor 11a Clutch 12 Electric compressor 20 Heat source side heat exchanger 20 (i) Heat source side heat exchanger unit (an example of unit)
21 On-off valve 22 Switching valve 30 Heat source side heat exchanger fan 40 Adjusting valve 40a Check valve 41 First adjusting valve 42 Second adjusting valve 43 Third adjusting valve 50 Use side heat exchanger 51 Refrigerant path 60 Drive source 61 Engine 62 Electric motor 71 Receiver 72 Refrigerant auxiliary evaporator 73 Refrigerant auxiliary evaporator adjustment valve 74 Auxiliary heat exchanger 81 Oil separator 82 Accumulator 91 Subcooling heat exchanger 92 Subcooling heat exchanger adjustment valve 100A Heat pump 100B Heat pump 101 Use side heat exchanger 102 Heat source side heat exchanging part 102a Package 110 Refrigerant circuit 111 Four-way valve 111a Inlet 111b Outlet 111c One connection port 111d The other connection port 112 Bridge circuit 114 First switching valve 115 Second switching valve 116 Check valve 120 Control device 121 Processing Unit 122 Storage Unit 151 Discharge Pressure Center Sensor 152 Suction pressure sensor 161 First suction temperature sensor 162 Second suction temperature sensor 163 Third suction temperature sensor 164 Air temperature sensor 165 Engine cooling water temperature sensor 166 Refrigerant condensation temperature sensor 171 Engine speed sensor 172 Motor speed sensor 200 Heat source side Heat exchanger section 300 Engine cooling water circuit 301 Cooling water circulation path 302 Cooling water bypass path 310 Exhaust gas heat exchanger 320 Radiator 330 Cooling water pump 340 Thermostatic switching valve P1 First intermediate connection point P2 Outflow connection point P3 Second intermediate connection Point P4 Inlet connection point P5 Junction point Q Branch point T Outside air temperature Tc Refrigerant condensation temperature Th Predetermined upper limit temperature Ts Predetermined temperature Tw Engine coolant temperature W Refrigerant flow direction

Claims (3)

The engine-driven compressor and the electric compressor are housed in a common package and a refrigerant circuit that circulates the refrigerant is shared by the engine-driven compressor and the electric compressor,
The heat source side heat exchanger is configured so that the condensation capacity of the heat source side heat exchanger can be changed,
When performing a cooling operation, when the temperature of air exchanged by the heat source side heat exchanger is equal to or lower than a predetermined temperature, the condensation capacity of the heat source side heat exchanger is made smaller than the maximum condensation capacity. A heat pump characterized by The heat pump according to claim 1,
The heat source side heat exchanger is composed of a plurality of units,
An opening / closing valve is provided in at least one branch path among the branch paths upstream of the heat source side heat exchanger in the flow direction of the discharge gas refrigerant discharged from the engine-driven compressor and / or the electric compressor;
When performing the cooling operation, when the temperature of the air exchanged in the heat source side heat exchanger is equal to or lower than the predetermined temperature, the condensation capacity of the heat source side heat exchanger is made smaller than the maximum condensation capacity. A heat pump for controlling the on-off valve. The engine-driven compressor and the electric compressor are housed in a common package and a refrigerant circuit that circulates the refrigerant is shared by the engine-driven compressor and the electric compressor,
Between the refrigerant and engine cooling water that cools the engine in a branch path branched upstream of the heat source side heat exchanger in the flow direction of the discharge gas refrigerant discharged from the engine-driven compressor and / or the electric compressor An auxiliary heat exchanger is installed to exchange heat at
When performing a cooling operation, when the temperature of air exchanged by the heat source side heat exchanger is equal to or lower than a predetermined temperature, the engine is stopped and the temperature of the engine cooling water is the heat source side. A heat pump, wherein the flow direction of the discharged gas refrigerant is directed toward the auxiliary heat exchanger when the temperature is higher than the temperature of air exchanged by the heat exchanger.

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