WO2016084817A1

WO2016084817A1 - Vehicle air-conditioning device

Info

Publication number: WO2016084817A1
Application number: PCT/JP2015/082976
Authority: WO
Inventors: 畠山　淳; 智荻原; 裕之大野
Original assignee: カルソニックカンセイ株式会社
Priority date: 2014-11-27
Filing date: 2015-11-25
Publication date: 2016-06-02

Abstract

This vehicle air-conditioning device is provided with a first coolant circulation path along which a coolant travels through an engine, a second coolant circulation path that communicates with the first coolant circulation path and along which the coolant travels through a vehicle-cabin radiator, a blocking mechanism that blocks the communication between the first coolant circulation path and the second coolant circulation path when the blocking mechanism is switched to a blocking state, and a refrigeration cycle. The refrigeration cycle has a compressor that compresses a refrigerant, a secondary evaporator in which the refrigerant absorbs heat from the coolant in the first coolant circulation path, a secondary condenser in which the refrigerant that has absorbed heat at the secondary evaporator dissipates heat to the coolant in the second coolant circulation path, and a secondary expander that reduces the pressure of the refrigerant that has traveled through the secondary condenser.

Description

Air conditioner for vehicles

The present invention relates to a vehicle air conditioner.

JP2011-131871A discloses a vehicle air conditioner that is mounted on a hybrid vehicle, circulates engine cooling water between a heater core and an engine, and heats air that has passed through an evaporator by heat exchange with engine cooling water. Has been. This vehicle air conditioner includes a heat absorption side heat exchanger provided on the downstream side of the heater core, a heat radiation side heat exchanger provided on the upstream side of the heater core, and between the heat absorption side heat exchanger and the heat radiation side heat exchanger. A Peltier element provided. When the engine is stopped, the temperature of the engine coolant flowing into the heater core is not lowered by the Peltier element transferring heat from the engine coolant flowing on the downstream side of the heater core to the engine coolant flowing on the upstream side of the heater core. ing.

However, in the vehicle air conditioner of JP2011-131871A, the engine cooling water whose temperature has decreased in the heat absorption side heat exchanger circulates and is led to the heat radiation side heat exchanger again. For this reason, the engine coolant once cooled is reheated, and the energy efficiency may be reduced.

An object of the present invention is to suppress a decrease in energy efficiency due to reheating of cooling water.

According to an aspect of the present invention, a vehicle air conditioner having a vehicle interior radiator that heats air guided into the vehicle interior of the vehicle includes a first cooling water circulation passage through which cooling water passes through the engine, and the first cooling. A second cooling water circulation passage that communicates with the water circulation passage and through which the cooling water passes through the radiator in the vehicle interior; and a communication between the first cooling water circulation passage and the second cooling water circulation passage when switched to the shut-off state. A shut-off mechanism that shuts off, a compressor that compresses the refrigerant, a sub-evaporator that absorbs heat from the cooling water in the first cooling water circulation passage, and the second cooling water circulation passage from the refrigerant that absorbs heat in the sub-evaporator A refrigeration cycle comprising: a sub-condenser that radiates heat to the cooling water therein; and a sub-expander that decompresses the refrigerant that has passed through the sub-condenser.

In this aspect, the refrigeration cycle moves heat from the first cooling water circulation passage through which the cooling water passes through the engine to the second cooling water circulation passage through which the cooling water passes through the vehicle interior radiator via the refrigerant. The communication between the first cooling water circulation passage and the second cooling water circulation passage can be blocked by a blocking mechanism. Therefore, in a state in which the shut-off mechanism is switched to the shut-off state, the cooling water circulating in the second cooling water circulation passage is not cooled once and then reheated. Therefore, it is possible to suppress a decrease in energy efficiency due to reheating of the cooling water.

FIG. 1 is a configuration diagram of a vehicle air conditioner according to a first embodiment of the present invention. FIG. 2 is a configuration diagram illustrating a specific configuration of the first cooling water circulation passage. FIG. 3 is a diagram illustrating a refrigerant recovery mode of the vehicle air conditioner. FIG. 4 is a diagram illustrating a heat pump heating mode of the vehicle air conditioner. FIG. 5 is a diagram illustrating an engine heating mode of the vehicle air conditioner. FIG. 6 is a configuration diagram illustrating a modification of the heater unit. FIG. 7 is a diagram illustrating a cooling mode of the vehicle air conditioner. FIG. 8 is a diagram illustrating a cold storage mode of the vehicle air conditioner. FIG. 9 is a flowchart for explaining the operation mode switching control in the vehicle air conditioner according to the first embodiment of the present invention. FIG. 10 is a time chart for explaining the operation of the vehicle air conditioner. FIG. 11 is a configuration diagram of a vehicle air conditioner according to a modification of the first embodiment of the present invention. FIG. 12 is a configuration diagram of a vehicle air conditioner according to the second embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
First, an overall configuration of a vehicle air conditioner 100 according to a first embodiment of the present invention will be described with reference to FIG.

The vehicle air conditioner 100 is an air conditioner mounted on a vehicle 1 having an engine stop function for stopping the engine when the vehicle is stopped or running, such as a hybrid vehicle (HEV). The vehicle 1 includes an engine 9 that is used for driving wheels and generating electric power, and a radiator 8 that cools the engine 9 with circulating cooling water.

The vehicle air conditioner 100 cools and dehumidifies the air passage 2 having the air introduction port 21, the blower unit 3 that introduces air from the air introduction port 21 and flows it to the air passage 2, and the air flowing through the air passage 2. A heat pump unit 4 as a refrigeration cycle and a heater unit 6 that warms the air flowing through the air passage 2 are provided.

The air sucked from the air inlet 21 flows through the air passage 2. The air passage 2 sucks outside air outside the passenger compartment and inside air inside the passenger compartment. The air that has passed through the air passage 2 is guided into the passenger compartment.

The blower unit 3 has a blower 31 as a blower that causes air to flow through the air passage 2 by rotation around the shaft center. The blower unit 3 has intake doors (not shown) for opening and closing an outside air inlet for taking in outside air outside the vehicle compartment and an inside air inlet for taking in air inside the vehicle interior. The blower unit 3 can adjust the opening / closing or opening degree of the outside air inlet and the inside air inlet, and can adjust the intake amount of the outside air outside the passenger compartment and the inside air inside the passenger compartment.

The heat pump unit 4 includes a refrigerant circulation circuit 41 that circulates refrigerant, an electric compressor 42 that is driven by an electric motor (not shown) and compresses the refrigerant, and refrigerant that is compressed by the electric compressor 42 during cooling. The outdoor heat exchanger 43 that dissipates heat and condenses, the expansion valve 44 that lowers the temperature by decompressing the condensed refrigerant, and expands the air, and the air that flows through the air passage 2 by the refrigerant that has expanded and lowered the temperature. And an evaporator 45 as a main evaporator to be cooled.

The electric compressor 42 is, for example, a vane-type rotary compressor, but a scroll-type compressor may be used. The rotational speed of the electric compressor 42 is controlled by a command signal from a controller (not shown).

An accumulator 46 is provided upstream of the electric compressor 42. The accumulator 46 temporarily accumulates the surplus of the refrigerant sent from the evaporator 45 and sends only the gaseous refrigerant to the electric compressor 42.

The outdoor heat exchanger 43 during cooling cools and liquefies the refrigerant by heat exchange with the outside air. The outdoor heat exchanger 43 at this time includes a main outdoor heat exchanger 43a that liquefies the gaseous refrigerant, a liquid tank 43b that stores the liquid refrigerant, and a supercooling outdoor heat exchanger 43c that further cools the liquid refrigerant. .

The expansion valve 44 expands the liquid refrigerant cooled by the outdoor heat exchanger 43 to further lower the temperature. The expansion valve 44 has a temperature sensing cylinder (not shown) attached to the outlet side of the evaporator 45, and the opening degree is automatically adjusted so that the degree of superheat of the refrigerant on the outlet side of the evaporator 45 is maintained at a predetermined value. Adjusted.

The evaporator 45 performs heat exchange between the liquid refrigerant decompressed by the expansion valve 44 and the air flowing through the air passage 2. The evaporator 45 is provided in the air passage 2 and cools and dehumidifies the air flowing through the air passage 2. In the evaporator 45, the liquid refrigerant evaporates by the heat of the air flowing through the air passage 2, and becomes a gaseous refrigerant. The gaseous refrigerant evaporated by the evaporator 45 is supplied again to the electric compressor 42 via the accumulator 46.

The heat pump unit 4 also radiates heat to the cooling water in the heater circuit 70 (to be described later) from the evaporator 51 as a sub-evaporator that absorbs heat from the cooling water in the engine cooling circuit 60 (to be described later) and the refrigerant that has absorbed heat in the evaporator 51. A condenser 52 serving as a sub-condenser, an orifice 53 serving as a sub-expander that decompresses the refrigerant that has passed through the condenser 52, a state where the refrigerant compressed by the electric compressor 42 is guided to the evaporator 51, and a state where the refrigerant is guided to the evaporator 45. A three-way valve 54 as a switching valve for switching, a bypass passage 55 for circulating the refrigerant compressed by the electric compressor 42 by bypassing the orifice 53, and an opening / closing valve 56 as a bypass valve for opening and closing the bypass passage 55 Also have.

The evaporator 51 performs heat exchange between the refrigerant that has been decompressed through the condenser 52 and the orifice 53 and the radiator 62 of the engine cooling circuit 60 described later. The gaseous refrigerant evaporated by the evaporator 51 is supplied again to the electric compressor 42 via the accumulator 46.

The capacitor 52 cools the refrigerant by heat exchange with a heat absorber 72 of the heater circuit 70 described later.

The orifice 53 reduces the pressure by reducing the flow of the refrigerant. The orifice 53 expands the refrigerant cooled by the condenser 52 to lower the temperature further. Instead of the orifice 53, a temperature expansion valve or a capillary tube may be used as a sub-expander.

The three-way valve 54 is switched by a command signal from the controller. When the three-way valve 54 is switched so as to guide the refrigerant compressed by the electric compressor 42 to the evaporator 45, the refrigerant passes through the outdoor heat exchanger 43, the expansion valve 44, the evaporator 45, and the accumulator 46 and again becomes the electric compressor 42. To be supplied. On the other hand, when the three-way valve 54 is switched to a state in which the refrigerant compressed by the electric compressor 42 is guided to the evaporator 51, the refrigerant passes through the evaporator 51, passes through the return passage 57, and again through the accumulator 46. To be supplied.

The bypass passage 55 communicates the upstream of the condenser 52 and the downstream of the orifice 53 in the refrigerant circulation circuit 41.

The on-off valve 56 is switched by a command signal from the controller. The on-off valve 56 communicates the bypass passage 55 when switched to the open state, and shuts off the bypass passage 55 when switched to the closed state. When the on-off valve 56 causes the bypass passage 55 to communicate, the refrigerant guided from the electric compressor 42 bypasses the condenser 52 and the orifice 53 and is guided to the three-way valve 54 without being decompressed. Instead of the on-off valve 56, a three-way valve that switches between a state in which the refrigerant guided from the electric compressor 42 is guided to the condenser 52 and a state in which the refrigerant is guided to the bypass passage 55 may be used.

The heater unit 6 includes an engine cooling circuit 60 that cools the engine 9 with cooling water, and a heater circuit that heats a heater core 75 serving as a vehicle interior radiator that heats the air guided to the vehicle interior of the vehicle 1 through the air passage 2 using the cooling water. 70 and a three-way valve 7 as a shut-off mechanism that shuts off the communication between the engine cooling circuit 60 and the heater circuit 70 when switched to the shut-off state.

The engine cooling circuit 60 is opposed to the cooling water circulation passage 63 as the first cooling water circulation passage through which the cooling water circulates, the water pump 61 that circulates the cooling water in the cooling water circulation passage 63, and the evaporator 51 of the heat pump unit 4. And a radiator 62 provided. The coolant circulation passage 63 circulates coolant in the engine 9 of the vehicle 1. The cooling water circulation passage 63 can also circulate cooling water to the radiator 8 of the vehicle 1.

The heat radiator 62 exchanges heat with the evaporator 51. Specifically, the radiator 62 heats and evaporates the liquid refrigerant flowing in the evaporator 51. In FIG. 1, a part of the configuration of the cooling water circulation passage 63 is omitted. A specific configuration of the cooling water circulation passage 63 will be described later in detail with reference to FIG.

The heater circuit 70 includes a cooling water circulation passage 73 as a second cooling water circulation passage through which the cooling water circulates, a water pump 71 that circulates the cooling water in the cooling water circulation passage 73, and a heat absorber 72 that is provided to face the condenser 52. And a heater core 75 disposed in the air passage 2.

The heat absorber 72 exchanges heat with the condenser 52. Specifically, the heat absorber 72 cools the gaseous refrigerant flowing in the condenser 52.

The three-way valve 7 is switched by a command signal from the controller. When the three-way valve 7 is switched to the communication state, the communication passage 65 communicates and the cooling water circulation passage 63 and the cooling water circulation passage 73 communicate. In this case, the cooling water heated by the engine 9 passes through the three-way valve 7 and is guided to the heater core 75. On the other hand, when the three-way valve 7 is switched to the shut-off state, the communication passage 65 is shut off, and the communication between the coolant circulation passage 63 and the coolant circulation passage 73 is shut off. In this case, the cooling water circulates independently in the cooling water circulation passage 63 and the cooling water circulation passage 73. Instead of the three-way valve 7, an on-off valve that switches the communication passage 65 between a communication state and a cutoff state may be used as a cutoff mechanism.

A mix door 76 is provided upstream of the heater core 75 in the air passage 2 to adjust the flow rate of the air flowing through the air passage 2 between the air guided to the heater core 75 and the air bypassing the heater core 75. The mix door 76 operates in response to a command signal from the controller.

Next, a specific configuration of the cooling water circulation passage 63 will be described with reference to FIG.

As shown in FIG. 2, the engine 9 has a cylinder block 9b in which a cylinder (not shown) in which a piston (not shown) reciprocates is formed, an intake port (not shown), and an exhaust port (not shown). And a cylinder head 9a fastened and fixed to the upper part of the cylinder block 9b. In the warm-up operation at the time of cold start of the engine 9, the cylinder head 9a is heated closer to the combustion chamber, so the amount of heat generated by the operation of the engine 9 is larger than that of the cylinder block 9b.

The cooling water circulation passage 63 includes a first cooling water passage 63a formed in the cylinder head 9a through which cooling water passes, a second cooling water passage 63b formed in the cylinder block 9b through which cooling water passes, and a second cooling water passage 63b. And a thermostat 63c as a temperature on / off valve that is switched from a closed state to an open state when the temperature of the cooling water led to the temperature exceeds a predetermined temperature. That is, the first cooling water passage 63a is formed in a part of the engine 9, and the second cooling water passage 63b has a heat generation amount due to the operation of the engine 9 as compared with the portion in which the first cooling water passage 63a is formed. Formed on another part of the small engine 9.

The cooling water circulation passage 63 has a thermostat 8a as a temperature on / off valve provided upstream of the radiator 8 in the cooling water passage connecting the radiator 8 and the engine 9. The thermostat 8a is switched from the closed state to the open state when the temperature of the cooling water led to the radiator 8 exceeds a predetermined temperature. The predetermined temperature at which the thermostat 63c is switched to the open state is set lower than the predetermined temperature at which the thermostat 8a is switched to the open state.

The cooling water circulation passage 63 has an exhaust heat exchanger 64 in which the cooling water absorbs heat from the exhaust of the engine 9 downstream of the engine 9 and upstream of the position where the evaporator 51 is provided. The exhaust heat exchanger 64 is, for example, an exhaust heat recovery device that absorbs heat from exhaust gas exhausted from an exhaust pipe (not shown) and recovers exhaust heat, or an EGR (Exhaust) that recirculates part of the exhaust gas to the intake side. A gas recirculation (EGR) cooler provided in a gas recirculation device (not shown) for cooling EGR gas.

Hereinafter, the operation of the vehicle air conditioner 100 will be described mainly with reference to FIGS. 3 to 10.

In the vehicle air conditioner 100, the air introduced into the air passage 2 from the air inlet 21 is first guided to the heat pump unit 4 by the blower 31. In the heat pump unit 4, the air flowing through the air path 2 is cooled and dehumidified by heat exchange with the evaporator 45.

The air that has passed through the evaporator 45 is divided by the mix door 76 into air that is guided to the heater core 75 and air that bypasses the heater core 75. The air guided to the heater core 75 is warmed by heat exchange with the heater core 75. Then, the air heated by the heater core 75 and the air bypassing the heater core 75 are merged again and guided into the vehicle interior. As described above, the vehicle air conditioner 100 adjusts the temperature and humidity of the air introduced into the air passage 2 from the air introduction port 21 and guides it into the vehicle interior.

Next, each operation mode will be described with reference to FIGS. 3 to 8, a passage through which the refrigerant or the cooling water circulates is indicated by a thick solid line, and a passage where the refrigerant or the cooling water circulates is indicated by a broken line.

In the vehicle air conditioner 100, the three-way valve 7 shuts off the cooling water circulation passage 63 and the cooling water circulation passage 73 while the three-way valve 7 blocks the cooling water circulation passage 63 and the cooling water circulation passage 73, and the heat pump unit. Heating operation is performed in any of the heat pump heating mode in which 4 operates.

<Refrigerant recovery mode>
The operation in the refrigerant recovery mode is performed at least once when switching from the cooling operation to the heating operation, as in the beginning of the season when heating is required, such as late autumn or early winter. Alternatively, it is also performed when switching from the dehumidifying heating operation to the heating operation. The operation in the refrigerant recovery mode is performed continuously for about 1 minute, for example, and then switched to the heating operation. As shown in FIG. 3, in the refrigerant recovery mode, the three-way valve 54 is switched to a state in which the refrigerant is guided to the outdoor heat exchanger 43. The on-off valve 56 is switched to the closed state. The three-way valve 7 is switched to the cutoff state.

Thereby, in the heat pump unit 4, the refrigerant compressed by the electric compressor 42 passes through the condenser 52 and is cooled, and a part thereof is liquefied. Next, the refrigerant passes through the orifice 53 and is depressurized, and evaporates in the outdoor heat exchanger 43. At this time, the outdoor heat exchanger 43 functions as an evaporator. The vaporized refrigerant passes through the expansion valve 44, is led to the evaporator 45, and is supplied again to the electric compressor 42 via the accumulator 46. At this time, the cooling water circulates independently in the cooling water circulation passage 63 and the cooling water circulation passage 73.

Thus, in the vehicle air conditioner 100, by operating in the refrigerant recovery mode, the refrigerant in the outdoor heat exchanger 43 is evaporated by depressurizing the outdoor heat exchanger 43 at the orifice 53, and the electric compressor The refrigerant is sucked into 42. Therefore, the liquid refrigerant that has fallen in the outdoor heat exchanger 43 can be recovered, and the amount of refrigerant circulating in the heat pump heating mode can be ensured. In the vehicle air conditioner 100, preparation for performing the heating operation in the heat pump heating mode is performed by operating in the refrigerant recovery mode.

<Heat pump heating mode>
The operation in the heat pump heating mode is performed in a state where the temperature of the cooling water is relatively low. As shown in FIG. 4, in the heat pump heating mode, the three-way valve 54 is switched to a state in which the refrigerant is guided to the evaporator 51. The on-off valve 56 is switched to the closed state. The three-way valve 7 is switched to the cutoff state.

Thereby, in the heat pump unit 4, the refrigerant compressed by the electric compressor 42 passes through the condenser 52 and the orifice 53 and is cooled, and a part thereof is liquefied. At this time, the heat of the refrigerant moves from the condenser 52 to the heat absorber 72, and the cooling water in the heater circuit 70 is warmed.

The refrigerant that has passed through the orifice 53 is guided to the evaporator 51 through the three-way valve 54. In the evaporator 51, the heat is transferred from the cooling water of the radiator 62 to the refrigerant of the evaporator 51, whereby the refrigerant is warmed. Therefore, a part or all of the refrigerant guided to the evaporator 51 evaporates and is guided to the return passage 57. The refrigerant warmed by the evaporator 51 is supplied again to the electric compressor 42 via the accumulator 46. At this time, the cooling water circulates independently in the cooling water circulation passage 63 and the cooling water circulation passage 73.

Thus, in the heat pump heating mode, the heat pump unit 4 moves heat from the engine cooling circuit 60 to the heater circuit 70 via the refrigerant. Therefore, in the vehicle air conditioner 100, the heater core 75 is warmed by the heat of the engine 9 moved by the heat pump unit 4, and the heating operation is performed.

At this time, since the communication between the cooling water circulation passage 63 and the cooling water circulation passage 73 is blocked by the three-way valve 7, the cooling water circulating in the cooling water circulation passage 73 is never reheated after being cooled once. Therefore, it is possible to suppress a decrease in energy efficiency due to reheating of the cooling water.

Here, for example, when the operation in the heat pump heating mode is performed when the engine 9 is cold-started, the heat of the engine 9 moves to the cooling water circulation passage 73 via the heat pump unit 4 in order to warm the heater core 75. Therefore, it may take time for the engine 9 to warm up.

On the other hand, as shown in FIG. 2, in the engine cooling circuit 60, the cooling water circulation passage 63 includes a first cooling water passage 63a formed in the cylinder head 9a and a second cooling water formed in the cylinder block 9b. And a passage 63b. While the temperature of the cooling water is relatively low, the thermostat 63c is in a closed state, so that the cooling water passes through the first cooling water passage 63a but does not pass through the second cooling water passage 63b. Therefore, when the temperature of the cooling water is relatively low, the cooling water passes only through the cylinder head 9a whose temperature rises quickly and close to the combustion chamber, so that the cooling water is efficiently heated without impairing the warm air of the cylinder block 9b. be able to.

The cooling water circulation passage 63 has an exhaust heat exchanger 64 that absorbs heat from the exhaust of the engine 9 by the cooling water. Therefore, the cooling water before heat exchange with the evaporator 51 can also be warmed by the exhaust heat of the engine 9. Therefore, the operation of the heat pump unit 4 can be started at an early stage, and the warm-up operation of the engine 9 can be performed quickly.

And when the cooling water circulating through the cooling water circulation passage 63 exceeds a predetermined temperature, the thermostat 63c is switched from the closed state to the open state. Thus, the cooling water passes through both the first cooling water passage 63a and the second cooling water passage 63b. Therefore, the cooling water is warmed by the heat of both the cylinder head 9a and the cylinder block 9b.

<Engine heating mode>
The operation in the engine heating mode is performed in a state where the temperature of the cooling water is higher than that in the heat pump heating mode. As shown in FIG. 5, in the engine heating mode, the operation of the electric compressor 42 is stopped, and the refrigerant does not circulate in the heat pump unit 4. The three-way valve 7 is switched to the communication state.

Thereby, the cooling water circulation passage 63 and the cooling water circulation passage 73 communicate with each other, and the cooling water heated by the engine 9 is guided to the heater core 75. Therefore, in the vehicle air conditioner 100, the heater core 75 is warmed by the heat of the engine 9, and the heating operation is performed.

As shown in FIG. 6, when the three-way valve 7 is switched to the communication state, the communication passage portion 73a of the cooling water circulation passage 73 through which the cooling water passes only when the cooling water does not pass and is switched to the shut-off state. A water pump 71 may be provided. In this case, it is possible to stop the operation of the water pump 71 and operate only the water pump 61 to perform the heating operation in the engine heating mode.

<Cooling mode>
As shown in FIG. 7, in the cooling mode, the three-way valve 54 is switched to a state in which the refrigerant is guided to the evaporator 45. The on-off valve 56 is switched to the open state.

Thereby, in the heat pump unit 4, the refrigerant compressed by the electric compressor 42 is guided to the condenser via the on-off valve 56 and the three-way valve 54. The refrigerant guided to the outdoor heat exchanger 43 is cooled and liquefied, further reduced to low temperature and low pressure by the expansion valve 44, and guided to the evaporator 45. The refrigerant guided to the evaporator 45 evaporates and is guided to the accumulator 46. The refrigerant guided to the accumulator 46 is supplied to the electric compressor 42 again.

When the cooling operation is performed at the maximum capacity, the three-way valve 7 is switched to the shut-off state and the operation of the water pump 71 is stopped as shown in FIG. Therefore, since the cooling water does not circulate in the cooling water circulation passage 73, the heater core 75 is not warmed. At this time, the mix door 76 is closed so that the air flowing through the air passage 2 is not guided to the heater core 75. Therefore, the air cooled and dehumidified by the evaporator 45 is guided to the vehicle interior while being kept at a low temperature without being heated.

On the other hand, the three-way valve 7 may be switched to the communication state except when the cooling operation is performed at the maximum capacity. Thereby, the cooling water circulation passage 63 and the cooling water circulation passage 73 communicate with each other, and the cooling water heated by the engine 9 is guided to the heater core 75. Therefore, since the heater core 75 is warmed, the flow rate of the air guided to the heater core 75 and the air bypassing the heater core 75 out of the air flowing through the air passage 2 is adjusted by the mix door 76.

If the position of the mix door 76 is adjusted to increase the flow rate of the air guided to the heater core 75 out of the air flowing through the air passage 2, the air dehumidified by the evaporator 45 is heated by the heater core 75 and guided to the vehicle interior. It becomes dehumidification heating operation.

<Cool storage mode>
The operation in the cold storage mode is performed mainly during the cooling operation in a hot season. The operation in the cold storage mode is performed in a state where the engine 9 is stopped. As shown in FIG. 8, in the cold storage mode, the three-way valve 54 is switched to guide the refrigerant to the evaporator 45 and the on-off valve 56 is switched to the open state, as in the cooling mode. In the cold storage mode, the three-way valve 7 is switched to the shut-off state.

Thus, the cooling water circulates independently in the cooling water circulation passage 63 and the cooling water circulation passage 73. Therefore, the cooling water warmed by the engine 9 is not guided to the heater core 75. Therefore, the cooling water in the cooling water circulation passage 73 is stored cold by the air that has been cooled and dehumidified through the evaporator 45 in the air passage 2 being guided to the heater core 75. And the air in the air path 2 can be cooled by flowing the cool-stored cooling water through the heater core 75 during the cooling operation. Therefore, energy consumption during the cooling operation can be suppressed.

Next, the operation mode switching control in the vehicle air conditioner 100 will be described with reference to FIG. The controller repeatedly executes the routine of FIG. 9 at regular intervals, for example, every 10 milliseconds.

In step S11, the target temperature Xm [° C.] is set. This target temperature Xm [° C.] is the temperature of the cooling water for the engine 9 that enables heating operation in the engine heating mode.

In step S12, it is determined whether or not the vehicle air conditioner 100 performs the heating operation. When it is determined in step S12 that the vehicle air conditioner 100 performs the heating operation, the process proceeds to step S13. On the other hand, when it is determined in step S12 that the vehicle air conditioner 100 does not perform the heating operation, the process proceeds to step S19 and the cooling operation in the cooling mode is performed.

In step S13, it is determined whether or not the vehicle air conditioner 100 was in a cooling operation or a dehumidifying heating operation when it was last operated. In step S13, when it is determined that the vehicle air conditioner 100 was in the cooling operation or the dehumidifying and heating operation during the previous operation, the process proceeds to step S16 and the operation in the refrigerant recovery mode is performed. On the other hand, when it is determined in step S13 that the vehicle air conditioner 100 was not in the cooling operation or the dehumidifying heating operation during the previous operation, the process proceeds to step S14.

In step S14, the cooling water temperature T [° C.] of the engine 9 is detected. Specifically, in step S14, the temperature of the cooling water in the cooling water circulation passage 63 is detected.

In step S15, whether or not T> Xm + 5 is satisfied when the temperature T [° C.] of the cooling water is increasing, or is T> Xm when the temperature T [° C.] of the cooling water is decreasing. Determine whether or not. At this time, Xm + 5 [° C.] corresponds to the first set temperature, and Xm [° C.] corresponds to the second set temperature. In addition, since 1st preset temperature should just be higher than 2nd preset temperature, it is not restricted to Xm + 5 [degreeC].

If it is determined in step S15 that T> Xm + 5 when the temperature of the cooling water rises or T> Xm when the temperature of the cooling water falls, the routine proceeds to step S17 and the heating operation in the engine heating mode is performed. Is done. On the other hand, if it is determined in step S15 that T ≦ Xm + 5 when the temperature of the cooling water is increased or T ≦ Xm when the temperature of the cooling water is decreased, the process proceeds to step S18 and the heat pump heating mode is performed. Heating operation is performed.

Thus, since the temperature of the cooling water rises in a state where the engine 9 is operating, the vehicle air conditioner 100 performs heat pump heating when the temperature of the cooling water in the cooling water circulation passage 63 is Xm + 5 [° C.] or less. The heating operation is performed according to the mode, and when the temperature of the cooling water in the cooling water circulation passage 63 becomes higher than Xm + 5 [° C.], the heating operation is performed by switching to the engine heating mode.

On the other hand, in the vehicle air conditioner 100, since the temperature of the cooling water decreases when the engine 9 is stopped, the engine heating mode is used when the temperature of the cooling water in the cooling water circulation passage 63 is higher than Xm [° C.]. When the temperature of the cooling water in the cooling water circulation passage 63 becomes Xm [° C.] or less, the heating operation is performed in the heat pump heating mode.

Next, the operation of the operation mode switching control of the vehicle air conditioner 100 during the heating operation will be described with reference to FIG.

10, the horizontal axis represents time t [s], and the vertical axis represents the cooling water temperature T [° C.]. In FIG. 10, the temperature of the cooling water of the engine 9 is indicated by a solid line, the temperature of the cooling water of the heater core 75 when the electric compressor 42 is continuously operated at the maximum output is indicated by a broken line, and the output control of the electric compressor 42 is controlled. The actual cooling water temperature of the heater core 75 to be performed is indicated by a thick solid line.

As shown in FIG. 10, when the operation of the vehicle air conditioner 100 is started, the temperature of the cooling water rises due to the heat of the engine 9. At this time, since the heating operation is performed in the heat pump heating mode, the heat of the cooling water in the cooling water circulation passage 63 is transferred to the cooling water in the cooling water circulation passage 73 by the heat pump unit 4. Therefore, the temperature of the cooling water that passes through the heater core 75 rises faster than the temperature of the cooling water that passes through the engine 9.

When the temperature of the cooling water passing through the heater core 75 rises to Xm + 5 [° C.], the output control of the electric compressor 42 is performed. Specifically, the controller adjusts the output of the electric compressor 42 so that the temperature of the cooling water passing through the heater core 75 is maintained at Xm + 5 [° C.].

When the temperature of the cooling water passing through the engine 9 exceeds Xm + 5 [° C.], the heating operation is performed by switching from the heat pump heating mode to the engine heating mode. At this time, since the cooling water circulation passage 63 and the cooling water circulation passage 73 communicate with each other, the temperature of the cooling water passing through the heater core 75 becomes equal to the temperature of the cooling water passing through the engine 9.

Thus, in the heat pump heating mode, the heat of the engine 9 is transmitted to the cooling water circulation passage 73 via the heat pump unit 4, so that it passes through the heater core 75 rather than the temperature of the cooling water in the cooling water circulation passage 63 that passes through the engine 9. The temperature of the cooling water in the cooling water circulation passage 73 that rises rises faster. Therefore, since the temperature of the heater core 75 rises quickly, the time for operating the engine 9 to warm the heater core 75 can be shortened.

According to the first embodiment described above, the following effects are obtained.

In the vehicle air conditioner 100, the heat pump unit 4 moves heat from the cooling water circulation passage 63 through which the cooling water passes through the engine 9 to the cooling water circulation passage 73 through which the cooling water passes through the heater core 75 via the refrigerant. The communication between the cooling water circulation passage 63 and the cooling water circulation passage 73 can be blocked by the three-way valve 7. Therefore, in a state where the three-way valve 7 is switched to the shut-off state, the cooling water circulating in the cooling water circulation passage 73 is never cooled and then reheated. Therefore, it is possible to suppress a decrease in energy efficiency due to reheating of the cooling water.

In the heat pump heating mode, the heat of the engine 9 is transmitted to the cooling water circulation passage 73 via the heat pump unit 4, so that the cooling that passes through the heater core 75 is lower than the temperature of the cooling water in the cooling water circulation passage 63 that passes through the engine 9. The temperature of the cooling water in the water circulation passage 73 rises faster. Therefore, since the temperature of the heater core 75 rises quickly, the time for operating the engine 9 to warm the heater core 75 can be shortened.

It should be noted that only the orifice 53 may be bypassed instead of the bypass passage 55 bypassing the capacitor 52 and the orifice 53 as in the modification shown in FIG. Also in this case, the operation in the refrigerant recovery mode, the heat pump heating mode, the engine heating mode, and the cooling mode is possible as in the above embodiment.

(Second Embodiment)
Next, a vehicle air conditioner 200 according to a second embodiment of the present invention will be described with reference to FIG. Note that in the second embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and redundant description will be omitted as appropriate.

In the second embodiment, a belt drive compressor 47 is applied instead of the electric compressor 42. In addition to the heat pump unit 4, a sub heat pump unit 5 is provided as a sub refrigeration cycle that moves the heat of the cooling water in the cooling water circulation passage 63 to the cooling water in the cooling water circulation passage 73.

In the second embodiment, similarly to the first embodiment, operation in the heat pump heating mode, the engine heating mode, the cooling mode, and the cold storage mode is possible. In the second embodiment, there is no need to perform the operation in the refrigerant recovery mode.

The heat pump unit 4 cools the refrigerant circulating circuit 41 through which the cooling refrigerant circulates, a belt-driven compressor 47 as a compressor driven by the engine 9 to compress the refrigerant, and the refrigerant compressed by the belt-driven compressor 47. An outdoor heat exchanger 43 that condenses the refrigerant, an expansion valve 44 that decompresses and expands the condensed refrigerant to lower the temperature, and an evaporator 45 that cools the air flowing through the air passage 2 using the refrigerant that has expanded and lowered the temperature. Have.

The sub heat pump unit 5 includes a refrigerant circulation circuit 59 in which the refrigerant circulates, an evaporator 51 that absorbs heat from the cooling water in the engine cooling circuit 60, and a capacitor that radiates heat from the refrigerant that has absorbed heat in the evaporator 51 to the cooling water in the heater circuit 70. 52, an orifice 53 that depressurizes the refrigerant that has passed through the condenser 52, and an electric compressor 58 that is smaller than the electric compressor 42.

In the heat pump heating mode, the three-way valve 7 is switched to the shut-off state. Thereby, the cooling water circulates independently in the cooling water circulation passage 63 and the cooling water circulation passage 73.

In the vehicle air conditioner 200, the sub heat pump unit 5 moves heat from the engine cooling circuit 60 to the heater circuit 70 via the refrigerant. Therefore, in the vehicle air conditioner 200, the heater core 75 is warmed by the heat of the engine 9 moved by the sub heat pump unit 5, and the heating operation is performed.

On the other hand, in the engine heating mode, the operation of the electric compressor 58 is stopped, and the refrigerant does not circulate in the sub heat pump unit 5. The three-way valve 7 is switched to the communication state.

Thereby, the cooling water circulation passage 63 and the cooling water circulation passage 73 communicate with each other, and the cooling water heated by the engine 9 is guided to the heater core 75. Therefore, in the vehicle air conditioner 200, the heater core 75 is warmed by the heat of the engine 9, and the heating operation is performed.

According to the second embodiment described above, similarly to the first embodiment, the sub heat pump unit 5 causes the cooling water circulation passage through which the cooling water passes through the heater core 75 from the cooling water circulation passage 63 through which the cooling water passes through the engine 9. Heat is transferred to 73 via the refrigerant. The communication between the cooling water circulation passage 63 and the cooling water circulation passage 73 can be blocked by the three-way valve 7. Therefore, in a state where the three-way valve 7 is switched to the shut-off state, the cooling water circulating in the cooling water circulation passage 73 is never cooled and then reheated. Therefore, it is possible to suppress a decrease in energy efficiency due to reheating of the cooling water.

The embodiment of the present invention has been described above. However, the above embodiment only shows a part of application examples of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above embodiment. Absent.

For example, in the above-described embodiment, instead of the electric compressor 42, a belt-driven compressor by an engine may be used. However, in this case, when the engine is stopped, the heating operation in the heat pump heating mode is not performed, and the heating operation in the engine heating mode is performed.

This application claims priority based on Japanese Patent Application No. 2014-239715 filed with the Japan Patent Office on November 27, 2014 and Japanese Patent Application No. 2015-227304 filed with the Japan Patent Office on November 20, 2015 The entire contents of this application are hereby incorporated by reference.

Claims

A vehicle air conditioner having a vehicle interior radiator that heats air introduced into the vehicle interior of the vehicle,
A first cooling water circulation passage through which cooling water passes through the engine;
A second cooling water circulation passage that communicates with the first cooling water circulation passage and through which the cooling water passes through the vehicle interior radiator;
A blocking mechanism for blocking communication between the first cooling water circulation passage and the second cooling water circulation passage when switched to a blocking state;
A compressor that compresses the refrigerant, a sub-evaporator that absorbs heat from the cooling water in the first cooling water circulation passage, and heat radiation from the refrigerant that has absorbed heat in the sub-evaporator to the cooling water in the second cooling water circulation passage. A vehicle air conditioner comprising: a sub-condenser that performs a refrigerating cycle, and a sub-expander that decompresses the refrigerant that has passed through the sub-condenser.
The vehicle air conditioner according to claim 1,
The first cooling water circulation passage is
A first cooling water passage formed in a part of the engine and through which cooling water passes;
A second cooling water passage that is formed in another part of the engine that generates a small amount of heat generated by operation of the engine as compared to a portion where the first cooling water passage is formed;
A temperature on-off valve that is switched from a closed state to an open state so that the cooling water passes through the second cooling water passage when the temperature of the cooling water guided to the second cooling water passage exceeds a predetermined temperature; Air conditioner.
The vehicle air conditioner according to claim 2,
The first cooling water circulation passage further includes an exhaust heat exchanger in which the cooling water absorbs heat from the exhaust of the engine upstream of a position where the sub-evaporator is provided.
The vehicle air conditioner according to any one of claims 1 to 3,
An engine heating mode in which the shut-off mechanism communicates the first cooling water circulation passage and the second cooling water circulation passage;
The vehicle air conditioner that performs the heating operation in any one of a heat pump heating mode in which the refrigeration cycle operates while the blocking mechanism blocks the first cooling water circulation passage and the second cooling water circulation passage.
The vehicle air conditioner according to claim 4,
In a state where the engine is operating, when the temperature of the cooling water in the first cooling water circulation passage is equal to or lower than a preset first setting temperature, heating operation is performed in the heat pump heating mode, and the first cooling water circulation passage A vehicle air conditioner that performs a heating operation in the engine heating mode when the temperature of the cooling water of the engine is higher than the first set temperature.
The vehicle air conditioner according to claim 5,
In a state where the engine is stopped, heating operation is performed by the heat pump heating mode when the cooling water in the first cooling water circulation passage is equal to or lower than a second set temperature set lower than the first set temperature, A vehicle air conditioner that performs a heating operation in the engine heating mode when cooling water in the first cooling water circulation passage is higher than the second set temperature.
The vehicle air conditioner according to any one of claims 1 to 6,
The refrigeration cycle is
An outdoor heat exchanger for cooling the refrigerant by heat exchange with the outside air;
A main expander that decompresses the refrigerant cooled in the outdoor heat exchanger;
A main evaporator that cools the air guided into the vehicle interior by the refrigerant decompressed by the main expander;
A switching valve for switching between a state in which the refrigerant compressed by the compressor is led to the sub-evaporator and a state to be led to the main evaporator;
A bypass valve that circulates the refrigerant compressed by the compressor by bypassing the sub-expander when switched to the open state;
A vehicle air conditioner that performs a cooling operation by switching the switching valve to a state in which refrigerant is guided to the main evaporator and switching the bypass valve to an open state.
The vehicle air conditioner according to claim 7,
A vehicle air conditioner that switches the shut-off mechanism to a shut-off state and cools the vehicle interior radiator with air guided into the vehicle interior when the engine is stopped during cooling operation.
The vehicle air conditioner according to claim 7 or 8,
When switching from the cooling operation or the dehumidifying heating operation to the heating operation, the sub-expansion valve is switched by switching the switching valve to a state in which the refrigerant is guided to the main evaporator and switching the bypass valve to a closed state. A vehicle air conditioner that evaporates the decompressed refrigerant in the outdoor heat exchanger to decompress the interior of the outdoor heat exchanger.