JPH05208611A - Vehicle air-conditioning device - Google Patents

Abstract

PURPOSE:To improve the comfortable feeling of driver or passenger by avoiding the rapid temperature change of the air blown out of the air-conditioning device into the vehicle chamber. CONSTITUTION:When the detected thermal load inputted in a control device 20 exceeds the preset critical value, the control device 20 increases the introduced quantity of the cooled air to a condenser 3 within the vehicle chamber from a steam compression cycle evaporator 5 by outputting the control signal to the first damper 11, or the temperature of the engine cooling water is measured respectively for the cases where the cooled air is distributed to a heater core 10 which makes use of the engine cooling water, and the cooled air is distributed to the condenser 3 in the vehicle chamber. The quantity of reduction and the quantity of reduction of the temperature at the rear surface of the radiator are compared with each other, and the control signal to select the larger effect value between the two is outputted to either the first damper 11 or the second damper 12, and the introducing quantity of the cooled air from the evaporator 5 to either the condenser 3 in the vehicle chamber or the heater core 10 is increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle cooling system which minimizes the temperature rise of blown air and reduces the heat radiation amount of a heat exchanger outside a vehicle when the heat load of the vehicle is severe.

[0002]

2. Description of the Related Art In a vehicle cooling system, a condenser as an exterior heat exchanger is arranged upstream of a radiator for cooling an engine, and the temperature rise of the cooling air there is accompanied by the temperature rise of the air flowing into the engine room. , Which causes a decrease in heat dissipation in the radiator. For this reason, conventionally, when the engine cooling water temperature becomes equal to or higher than the set value, the cooling device is stopped, or the heater core that recirculates the engine cooling water is ventilated to reduce the required heat radiation amount of the radiator.

[0003]

In the above-mentioned conventional example, the temperature of the cooling air in the condenser and the radiator rises, the cooling device is stopped, or the engine cooling water is recirculated to the heater core. In this case, the temperature of the air blown from the cooling device into the vehicle compartment may rise significantly, which may impair the occupant's comfort.

Therefore, in the present invention, a rapid temperature rise of the air blown into the vehicle compartment from the cooling device is avoided,
The challenge is to improve the comfort of the passengers (Actual Kaihei No. 1-93324).

[0005]

A first aspect of the present invention is directed to a compressor that adds work to a refrigerant, an exterior heat exchanger connected to the refrigerant discharge side of the compressor to radiate the heat of the refrigerant to the outside air, and this vehicle. A heat radiation type first vehicle interior heat exchanger connected to the refrigerant discharge side of the outdoor heat exchanger to radiate the heat of the refrigerant to the air introduced by the blowing means to generate warm air, and the first heat exchanger.
Expansion means connected to the refrigerant outflow side of the vehicle interior heat exchanger,
The heat of the air, which is connected to the refrigerant outflow side of the expansion means and is disposed between the blower means and the first vehicle interior heat exchanger, is introduced from the first vehicle interior heat exchanger by the air blower means. An endothermic second vehicle interior heat exchanger that radiates heat to the refrigerant supplied through the expansion means to generate cool air, and a second vehicle interior heat exchanger provided on the air introduction side of the first vehicle interior heat exchanger. The air distribution means for introducing all or part of the cool air into the first vehicle interior heat exchanger, the detection means for detecting the heat load of the vehicle, and the heat load from this detection means exceeds a preset limit value. And a control unit for outputting a control signal for increasing the amount of cold air introduced into the first vehicle interior heat exchanger to the air distribution unit.

According to a second aspect of the present invention, a third vehicle interior heat exchanger utilizing engine cooling water is attached downstream of the second vehicle interior heat exchanger to the air upstream of the third vehicle interior heat exchanger. An air distribution means for introducing all or part of the cold air from the second vehicle interior heat exchanger to the third vehicle interior heat exchanger is attached to the side, and the control means sets the heat load from the detection means in advance. When the cool air is distributed to the third vehicle interior heat exchanger and when the cool air is distributed to the first vehicle interior heat exchanger, the engine cooling water temperature reduction amount and The radiator rear surface temperature reduction margin is calculated and compared, and the control signal for increasing the amount of air introduced by selecting the one having the larger effect is sent to the air distribution means on the side of the first vehicle interior heat exchanger and the third vehicle interior. It is configured to output to either one of the air distribution means on the heat exchanger side.

[0007]

According to the first aspect of the present invention, during the cooling operation, the detection means detects the heat load of the vehicle, and when the detected heat load exceeds the limit value preset in the control device, the control device causes the air distribution means. The control signal is output, and the air distribution unit increases the amount of cold air introduced from the second vehicle interior heat exchanger.

According to the second aspect of the present invention, the detecting means detects the heat load of the vehicle during the cold wind operation, and when the detected heat load exceeds the limit value preset in the control device, the control device is controlled by the third device.
The engine cooling water temperature reduction margin and the radiator rear surface temperature reduction margin were calculated and compared for the case where cold air was distributed to the vehicle interior heat exchanger and the case where cold air was distributed to the first vehicle interior heat exchanger, respectively. , Selecting the one having the larger effect and outputting the control signal to one of the air distribution means on the side of the first vehicle interior heat exchanger and the air distribution means on the side of the third vehicle interior heat exchanger,
Either one of the air distribution means increases the amount of cold air introduced from the second vehicle interior heat exchanger.

[0009]

【Example】

 First Embodiment FIG. 1 shows a vehicle air conditioner of one embodiment.

In FIG. 1, the refrigerant discharge side of the compressor 1 is connected to the refrigerant inflow side of the vehicle exterior heat exchanger 2. The refrigerant inflow side of the first vehicle interior heat exchanger 3 is connected to the refrigerant discharge side of the vehicle exterior heat exchanger 2. A refrigerant inflow side of the first vehicle interior heat exchanger 3 is connected to a refrigerant inflow side of an expansion valve 4 that adiabatically expands the liquid refrigerant into an atomized state as expansion means provided outside the vehicle compartment such as an engine room. ing. The second vehicle interior heat exchanger 5 is provided on the refrigerant inflow side of the expansion valve 4.
Is connected to the refrigerant inflow side. Second vehicle interior heat exchanger 5
The refrigerant inlet side of the compressor 1 is connected to the refrigerant outlet side of the vehicle via a receiver 6 provided outside the vehicle compartment.

Here, the compressor 31 is an internal variable type variable capacity compressor which is provided outside the passenger compartment,
The temperature of the air blown out from the second vehicle interior heat exchanger 5 is controlled to a certain set value. Exterior heat exchanger 2
Are arranged in parallel in front of a radiator (not shown) that cools the engine cooling water outside the vehicle compartment, and is an outside-vehicle condenser that radiates the heat of the refrigerant discharged from the compressor 1 to the outside air. The first vehicle interior heat exchanger 3 is provided in a duct 7 as a main body of the apparatus, which is disposed in the vehicle interior front portion such as the back side of the instrument panel, and uses the heat of the refrigerant discharged from the compressor 1 as a blower. Is a heat dissipation type vehicle interior capacitor that radiates heat to the air introduced by the blower fan 8 of FIG. The second vehicle interior heat exchanger 5 is arranged between the blower fan 8 of the duct 7 and the first vehicle interior heat exchanger 3, and the heat of the air introduced by the blower fan 8 is transferred to the first vehicle interior heat exchanger. It is an endothermic evaporator that radiates heat to the refrigerant supplied from 3 through the expansion valve 4 to generate cold air.

An air inlet 9 for introducing the air inside the vehicle or the outside air is provided near the portion of the duct 7 where the blower fan 8 is arranged.
Is provided. A first damper 11, which is a first air distribution unit, is provided inside the duct 7 on the air upstream side of the second vehicle interior heat exchanger 3. The first damper 11 is opened and closed by the control device 20 so as to introduce all or part of the cold air passing through the second vehicle interior heat exchanger 5 into the first vehicle interior heat exchanger 3. Inside the duct 7 in the air downstream side of the second vehicle interior exchanger 3, there is provided a third heater core that uses engine cooling water.
A vehicle interior heat exchanger 10 is arranged. Third of duct 7
A second damper 12 serving as a second air distribution unit is provided on the air upstream side of the vehicle interior heat exchanger 10. Second damper 1
The controller 2 controls the control device 20 to transfer all or part of the cold air passing through the second vehicle interior heat exchanger 5 to the third vehicle interior heat exchanger 1.
Open and close to introduce 0. The portion of the duct 7 on the downstream side of the third vehicle interior heat exchanger 10 becomes an air mix chamber 13 as a room for producing temperature-controlled conditioned air by improving the mixing of the cold air and the warm air. There is.
The air mix chamber 13 has an air outlet 14 that communicates with a ventilator outlet (not shown), a foot outlet (not shown), and a defroster outlet (not shown) in order to blow out air as conditioned air into the passenger compartment. It is provided.

The control unit 20 includes a vehicle speed sensor 21, a transmission neutral switch 22, an engine suction negative pressure sensor 22, an engine speed sensor 23, and other operating condition detecting means, as well as an engine cooling water temperature sensor 24 and an outside air temperature sensor 25. And operating conditions such as vehicle speed, neutral position detection, engine suction negative pressure, engine speed, and the like from thermal load detection means such as a solar radiation sensor 26, an air conditioning air blowing air temperature sensor 27, and a compressor load sensor 28.
The opening degrees of the first damper 11 and the second damper 12 are controlled based on the engine cooling water temperature, the outside air temperature, the amount of solar radiation received by the vehicle, the temperature of the air conditioning air blow, and the heat load information such as the compressor load.

According to this embodiment, the driving of the compressor 1 causes the refrigerant to flow from the compressor 1 to the vehicle exterior heat exchanger 2
→ The first vehicle interior heat exchanger 3 → Expansion valve 4 → The second vehicle interior heat exchanger 5 → Receiver 6 → The compressor 1 circulates, and the vehicle exterior heat exchanger 2 heats the high temperature refrigerant discharged from the compressor 1. To the outside air, and by driving the blower fan 8, the heat of the air introduced into the duct 7 from the air introduction port 9 is radiated to the refrigerant by the second vehicle interior heat exchanger 5 to create cold air, and the control device 20 Controls the opening of the first damper 11 and the second damper 12, so that the first vehicle interior heat exchanger 3 and the third vehicle interior heat exchanger 10 are blown out from the second vehicle interior heat exchanger 5. Heat is radiated to all or part of the cold air to reheat it to create conditioned air of the target temperature, and warm air is created. The reheated hot air and the cold air are mixed in the air mix chamber 13 to obtain the target. Air-conditioned air with a blowing temperature is created, and this air-conditioned air is discharged Blown into the passenger compartment from an unillustrated ventilator outlet and a foot outlet, not shown, or a non-illustrated defroster outlet through 14.

The opening control of the first damper 11 and the second damper 12 will be described in detail with reference to the flow charts shown in FIGS. In these flowcharts, the main switch (not shown) of the vehicle is turned on, and the control device 20 is activated to start the processing.

FIG. 2 is a flow chart showing the opening control of the first and second dampers 11 and 12. When the cooling control starts, in step 101, the engine cooling water temperature Tw detected by the engine cooling water temperature sensor 24 is read, and in step 101, the engine cooling water temperature Tw detected in step 101 is equal to or higher than a preset limit value, which is a limit temperature. Determine if there is. If the detected engine cooling water temperature Tw is equal to or higher than the limit temperature (step 1
(YES at 02), immediately take measures to reduce the engine cooling water temperature Tw. Specifically, in step 103, the engine cooling water temperature reduction allowance ΔTeh when heat is radiated by the third vehicle interior heat exchanger 10 shown in FIG. 4 is calculated, and in step 104, the first vehicle interior heat exchange shown in FIG. The engine cooling water temperature reduction allowance ΔTe ₂ when heat is dissipated by the device 3 is calculated, and in step 105, the engine cooling water temperature reduction allowances ΔTeh and Δte ₂ are compared. And Δ
If Teh> ΔTe ₂ (step 105 returns to YE
S), in step 106, the second damper 12 is opened within a range in which the temperature rise of the air blown into the vehicle compartment is minimized. On the contrary, when ΔTeh ≦ ΔTe ₂ (NO in step 105), in step 107,
The first damper 11 is opened within a range in which the temperature rise of the air blown into the vehicle compartment is minimized.

Further, even if the engine cooling water temperature Tw detected in step 101 is below the limit temperature (step 10
2 is NO), in step 108, the rear surface temperature of the radiator is calculated from the operating conditions shown in FIG.
At 09, the radiator rear surface temperature calculated at step 108 is compared with the limit temperature. If the radiator rear surface temperature is equal to or higher than the limit value (YES in step 109).
S) Take measures to reduce the temperature of the rear surface of the radiator. Specifically, in step 110, the radiator rear surface temperature reduction allowance ΔTrh when heat is radiated by the third vehicle interior heat exchanger 10 shown in FIG. 4 is calculated, and in step 111, the first vehicle interior heat exchange shown in FIG. When the radiator 3 radiates heat, the radiator rear surface temperature reduction margin ΔTr ₂ is calculated, and step 112
In the above, both of the radiator rear surface temperature reduction margin ΔTr
Compare h and ΔTr ₂ . If ΔTrh> ΔTr ₂ (YES in step 112), step 106
In, the second damper 12 is opened in a range in which the temperature rise of the air blown into the vehicle compartment is suppressed to the minimum. vice versa,
If ΔTrh ≦ ΔTr ₂ (step 106 returns N
O), in step 113 similar to step 107, the first damper 11 is opened within a range in which the temperature rise of the air blown into the vehicle compartment is minimum.

FIG. 3 shows a flow chart for calculating the air temperature at the rear surface of the radiator. When the processing is started, in step 201, the engine suction negative pressure sensor 22
Read the engine suction negative pressure detected in Step 20,
At 2, the engine speed detected by the engine speed sensor 23 is read, and at step 203, the compressor load detected by the compressor load sensor 28 is read. In step 204, steps 201, 20
The engine cooling water heat radiation amount Qe from the engine intake load, the engine speed, and the compressor load detected at 2, 203.
Calculate ng. The calculation of the engine cooling water heat radiation amount Qeng is obtained by using a map preset in the control device 20 from an engine bench experiment. In step 205, the radiator passing air volume is calculated from the vehicle speed detected by the vehicle speed sensor 21, and in step 206, the radiator passing air temperature rise margin is obtained. Steps 201 to 2 above
In parallel with 03, in step 207, the outside air temperature detected by the outside air temperature sensor 25 is read, and in step 208, the air conditioning heat load of the vehicle is estimated from the outside air temperature detected in step 207 to estimate the heat radiation amount Qcond of the heat exchanger outside the vehicle interior.
Is calculated from the vehicle speed detected by the vehicle speed sensor 21 in step 209, and in step 210, an increase in air temperature outside the vehicle heat exchanger is calculated. Then, in step 211, the radiator rear surface air temperature is calculated by combining the radiator passage air temperature increase margin calculated in step 206 and the vehicle exterior heat exchanger passage air temperature increase margin calculated in step 210.

FIG. 4 shows a flowchart for calculating the engine cooling water temperature reduction margin ΔTeh and the radiator rear surface temperature reduction margin ΔTrh when heat is dissipated by the third vehicle interior heat exchanger 10. When the execution of the process is started, in step 301, the maximum heat radiation amount ΔQ ₂ that can be released by the second vehicle interior heat heat exchanger 5 shown in FIG. 6 is calculated. Then, radiating heat in the third vehicle interior heat exchanger 10 means that the engine cooling water heat radiation amount Q
Since eng corresponds to a reduction in that amount, step 30
2, the corrected engine cooling water heat radiation amount Qeng 'is calculated by subtracting the maximum heat radiation amount ΔQ ₂ from the engine cooling water heat radiation amount Qeng obtained in step 204 of FIG. In step 303, the radiator passing air volume is calculated from the vehicle speed detected by the vehicle speed sensor 21, and in step 304, the radiator passing air temperature increase margin is calculated. In parallel with this, in 305, the outside air temperature detected by the outside air temperature sensor 25 is read, and in step 306, the heat control load of the vehicle is estimated from the outside air temperature detected in step 305 to determine the heat radiation amount Qcond of the heat exchanger outside the vehicle compartment. Approximately, in step 307, the air volume passing through the vehicle exterior heat exchanger is calculated from the vehicle speed detected by the vehicle speed sensor 21, and in step 308, the radiator front air temperature Tarf is calculated.
Then, in step 309, the radiator passing air temperature rise amount obtained in step 304 and step 308
The radiator front surface temperature Tarf obtained in step S1 is combined with the radiator rear surface air temperature reduction allowance ΔTrh, and in step 310, the radiator cooling water temperature Tw detected in step 101 of FIG. 2 and the radiator front surface air temperature obtained in step 308 are calculated. Tarf and step 20 shown in FIG.
Using the engine cooling water heat radiation amount Qeng obtained in step 4 and the corrected engine cooling water heat radiation amount Qeng ′ obtained in step 302, the engine cooling water temperature reduction margin ΔTeh is calculated. The engine cooling water temperature reduction allowance ΔTeh is calculated by proportional calculation, considering that the temperature difference between the air temperature in the radiator and the cooling water temperature Tw is proportional to the radiator heat radiation amount.

FIG. 5 shows a flowchart for calculating the engine cooling water temperature reduction margin ΔTe ₂ and the radiator rear surface temperature reduction margin ΔTr ₂ when heat is dissipated in the first vehicle interior heat exchanger 3. When the process is started, in step 401, the maximum heat radiation amount ΔQ ₂ that can be released by the second vehicle interior heat heat exchanger 5 shown in FIG. 6 is calculated. Then, radiating heat in the first vehicle interior heat exchanger 3 corresponds to reducing the compressor power consumption by that amount.
Engine cooling water heat radiation amount Q obtained in step 204 of FIG.
A corrected engine cooling water heat radiation amount Qeng ′ is calculated by subtracting the maximum heat radiation amount ΔQ ₂ from eng. In step 403, the radiator passing air volume is calculated from the vehicle speed detected by the vehicle speed sensor 21, and in step 404, the radiator passing air temperature increase margin is calculated. In parallel with this,
At 405, the outside air temperature detected by the outside air temperature sensor 25 is read. Then, radiating heat in the first vehicle interior heat exchanger 3 corresponds to reducing the amount of heat radiation in the vehicle exterior heat exchanger 2, and therefore, in step 406, step 405.
From the outside heat exchanger heat dissipation Qcond estimated by estimating the heat control load of the vehicle from the outside air temperature detected in
A corrected exterior heat exchanger heat radiation amount Qcond 'is calculated by subtracting the maximum heat radiation amount ΔQ ₂ calculated in step 1, and step 407
At step 408, the air volume passing through the exterior heat exchanger is calculated from the vehicle speed detected by the vehicle speed sensor 21, and at step 408, the radiator front air temperature Tarf is calculated. This radiator front air temperature Tarf is the corrected exterior heat exchanger Qc.
Due to ond ', the temperature becomes lower than the radiator front surface air temperature Tarf obtained in step 308 of FIG. 4, and the engine cooling water temperature Tw decreases. And step 40
In step 9, the radiator passing air temperature increase amount obtained in step 404 and the radiator front surface temperature Tarf obtained in step 408 are combined to calculate the radiator rear surface air temperature reduction amount ΔTr ₂ , and in step 310, the radiator cooling water temperature Tw. And the radiator front air temperature Tarf obtained in step 408 and step 20 shown in FIG.
Using the engine cooling water heat radiation amount Qeng obtained in step 4 and the corrected engine cooling water heat radiation amount Qeng ′ obtained in step 402, the engine cooling water temperature reduction margin ΔTe ₂ is calculated. The engine cooling water temperature reduction allowance ΔTe ₂ is calculated by a proportional calculation, assuming that the temperature difference between the air temperature in the radiator and the cooling water temperature Tw is proportional to the radiator heat radiation amount.

FIG. 6 shows a flowchart for calculating the maximum heat radiation amount ΔQ ₂ that can be released by the second vehicle interior heat exchanger 5. When the execution of the process is started, the level of the blower fan motor applied voltage (not shown) that drives the blower fan 8 is detected in step 501, and the blower fan motor applied voltage level detected in step 501 is detected in step 502. The total air volume Ga is calculated.
In parallel with this, in step 503, the outside air temperature detected by the outside air temperature sensor 25 is read, and in step 504, the heat load of the vehicle is estimated from the outside air temperature detected in step 503. Then, in step 505, the blowout air temperature Tout of the second heat exchanger 5 is calculated from the blower fan total air amount Ga obtained in step 502 and the heat load of the vehicle due to the air conditioning heat load obtained in step 504. Then, in step 506, step 50
From the difference between the blowout air temperature Tout obtained in step 5 and the upper limit blowout temperature Tmax preset in the control device 20, the maximum heat radiation amount ΔQ that can be released by the second vehicle interior heat exchanger 5
Seeking ₂

Here, a pressure-enthalpy diagram of the cooling device of the above embodiment and the conventional cooling device in which reheating is performed only by the heater core using engine cooling water will be described with reference to FIG.

In FIG. 7, a pressure-enthalpy diagram of the conventional cooling device is shown by a dotted line. The dotted line a → b is expansion by the expansion valve, the dotted line b → ha is evaporation by the evaporator, the dotted line c → d is compression by the compressor, and the dotted line d → a is condensation by the condenser. On the other hand, the pressure-enthalpy diagram of the above embodiment is shown by a solid line. Solid line A → B
Indicates expansion by the expansion valve 4, solid line B → C indicates evaporation by the second vehicle interior heat exchanger 5, solid line C → D indicates compression by the compressor 1, and solid line D → A indicates condensation by the vehicle exterior heat exchanger 2.
Considering FIG. 7, in the above embodiment, the refrigerant after passing through the vehicle exterior heat exchanger 2 is further cooled by the first vehicle interior heat exchanger 3, so that the degree of supercooling increases and, by extension, the heating degree t. _C− t _C ′ increases, but normally the expansion valve 4 operates so as to keep the heating degree constant, so that the opening degree of the expansion valve 4 increases,
The pressure-enthalpy diagram has a flattened shape. Then, since the compressor 1 operates so as to make the temperature of the air blown out from the second vehicle interior heat exchanger 5 constant, the bottom of the pressure-enthalpy diagram does not change so much, and the recovery in the second vehicle interior heat exchanger 5 The amount of heat is secured. As a result, the power consumption i _D -i _C of the compressor 1 is reduced. On the other hand, condensation process D
→ A is shared by the heat radiation i _D −i _A ′ by the vehicle exterior heat exchanger 2 and the heat radiation i _A ′ -i _{A by} the first vehicle interior heat exchanger 3, so that the vehicle exterior heat exchanger 2 The amount of heat radiation decreases. Therefore, reheating with the first vehicle interior heat exchanger 3 is
Two effects are obtained: reduction of power consumption of the compressor 1 and reduction of air temperature in front of the radiator due to reduction of heat radiation amount of the vehicle exterior heat exchanger 2.

FIG. 8 shows the results of confirming the above effects in a bench test assuming an idle operation state. Considering FIG. 8, the heat radiation amount of the exterior heat exchanger 2 is 30
You can see that it is decreasing by nearly%. About 8% of the breakdown is due to the reduction of the power consumption of the compressor 1, and about 20% is due to the heat radiation from the first vehicle interior heat exchanger 3.
Needless to say, the amount of heat recovered by the engine in the cooling water is reduced by reducing the power consumption of the compressor 1.

Now, in order to improve the heat resistance of the actual vehicle, the above-mentioned effects are applied to idle conditions immediately after running under high load. Under this condition, the heat radiation amounts in the vehicle exterior heat exchanger 2 and the first vehicle interior heat exchanger 3 and the heat radiation amount in the radiator are approximately the same, and the heat radiation amount decrease in the vehicle exterior heat exchanger 2 is reduced in the engine room. In addition to having a great influence on the reduction of air temperature, the air temperature in front of the radiator is greatly lowered due to the small amount of cooling air, and the influence on the engine cooling water temperature is also large.

This effect was verified by an engine cooling water temperature simulation during idling. In this simulation, a phenomenon in which the amount of heat recovered from the engine cooling water changes with the water temperature and a phenomenon in which hot air in the engine room circulates in front of the condenser are folded in. The result of this simulation is shown in FIG. Considering FIG. 9, the engine cooling water temperature drops by about 4 ° C. and the radiator rear surface temperature drops by about 5 ° C. Then, the result of reducing the heat radiation amount of the engine cooling water by 20% is also shown, but the engine cooling water temperature is reduced to the same extent, while the radiator rear surface temperature is higher by 2 to 3 ° C. than in the above-described embodiment.

In the above example, the effect is great when the vehicle exterior heat exchanger 2 has a large amount of heat released during idling and when the vehicle exterior heat exchanger 2 has a small amount of air passing through it while climbing at medium speeds. Even in the outdoor heat exchanger 2, the effect is not great because the temperature rise is small. Therefore, depending on the operating conditions, it may be better to reduce the heat radiation amount of the engine cooling water by the heat radiation in the third vehicle interior heat exchanger 10.

[0028]

As described above, according to the first aspect of the present invention, when the heat load of the vehicle exceeds a preset limit value, the air distribution means is drive-controlled so that the second heat-absorbing type vehicle interior. Since the amount of cold air introduced from the heat exchanger to the heat dissipation type first passenger compartment heat exchanger is increased, the amount of heat dissipated by the passenger compartment outside heat exchanger can be increased without significantly increasing the temperature of the conditioned air that is blown into the passenger compartment. And the power consumption of the compressor can be reduced,
The heat resistance performance of the engine room under idle operating conditions can be greatly improved.

According to the second aspect of the present invention, when the heat load of the vehicle exceeds a preset limit value, when the cold air is distributed to the third heat exchanger in the passenger compartment and in the first heat exchanger in the passenger compartment. The engine cooling water temperature reduction margin and the radiator rear surface temperature reduction margin are calculated and compared for each of the cases where cold air is distributed, and the one with the greater effect is selected and the air distribution on the side of the first vehicle interior heat exchanger is selected. One of the means and the air distribution means on the side of the third vehicle interior heat exchanger is driven and controlled, so that the heat absorption type second vehicle interior heat exchanger to the heat radiation type first vehicle interior heat exchanger and engine cooling water. Since the amount of cold air introduced into either one of the third vehicle interior heat exchanger utilizing the above is increased, the above-mentioned effect of the first invention can be made more remarkable.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an entire embodiment of the present invention.

FIG. 2 is a flowchart showing a damper opening control according to an embodiment.

FIG. 3 is a flowchart for calculating a radiator rear surface air temperature according to an embodiment.

FIG. 4 is a flowchart for calculating a radiator rear air temperature reduction margin and an engine cooling water temperature reduction margin when the third vehicle interior heat exchanger of one embodiment is used.

FIG. 5 is a flowchart for calculating a radiator rear air temperature reduction margin and an engine cooling water temperature reduction margin when the first vehicle interior heat exchanger of one embodiment is used.

FIG. 6 is a flowchart for calculating a maximum heat radiation amount that can be released by the second vehicle interior heat exchanger according to the embodiment.

FIG. 7 is a pressure-enthalpy diagram of one example and a conventional example.

FIG. 8 is a result diagram of a bench experiment in idle operation of an example.

FIG. 9 is a chart showing the results of engine cooling water temperature simulation during idle operation in one example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Compressor 2 ... Vehicle exterior heat exchanger 3 ... 1st vehicle interior heat exchanger 4 ... Expansion valve (expansion means) 5 ... 2nd vehicle interior heat exchanger 8 ... Blower fan (blowing means) 10 ... 3rd vehicle compartment Heat exchanger 11 ... 1st damper (air distribution means) 12 ... 2nd damper (air distribution means) 20 ... Control device (control means) 24 ... Engine cooling water temperature sensor (detection means) 25 ... Outside air temperature sensor (detection means) 26 ... Insolation sensor (detection means) 27 ... Air-conditioning air blowing air temperature sensor (detection means) 28 ... Compressor load sensor (detection means)

Claims (2)

[Claims] 1. A compressor for compressing a refrigerant, a vehicle exterior heat exchanger connected to the refrigerant discharge side of the compressor for radiating heat of the refrigerant to the outside air, and a vehicle exterior heat exchanger connected to the refrigerant discharge side of the vehicle exterior heat exchanger. A heat radiation type first vehicle interior heat exchanger that radiates the heat of the refrigerant to the air introduced by the air blowing means to generate warm air, and an expansion means connected to the refrigerant outflow side of the first vehicle interior heat exchanger And the heat of air introduced by the blower means connected to the refrigerant outflow side of the expansion means and arranged between the blower means and the first vehicle interior heat exchanger. A second end-of-cabin heat exchanger of the endothermic type that radiates heat to the refrigerant supplied from the expansion unit through the expansion unit to generate cold air;
An air distribution unit that introduces all or part of the cold air from the vehicle interior heat exchanger into the first vehicle interior heat exchanger, a detection unit that detects the heat load of the vehicle, and a heat load from this detection unit is preset. And a control means for outputting to the air distribution means a control signal for increasing the amount of cold air introduced into the first vehicle interior heat exchanger when the determined limit value is exceeded. Cooling system. 2. A third vehicle interior heat exchanger utilizing engine cooling water is attached to the air downstream side of the second vehicle interior heat exchanger, and the third vehicle interior heat exchanger is provided with the third vehicle interior heat exchanger on the air upstream side. (2) An air distribution means for introducing all or a part of the cold air from the vehicle interior heat exchanger to the third vehicle interior heat exchanger is provided, and the control means controls the heat load from the detection means to a preset limit value. When the cool air is distributed to the third vehicle interior heat exchanger and the cool air is distributed to the first vehicle interior heat exchanger, the engine cooling water temperature reduction allowance and the radiator rear surface temperature are reduced. And a comparison is made, and the control signal for increasing the amount of air introduced is selected by selecting the one having the larger effect and the first
The vehicle air conditioner according to claim 1, wherein the air is output to either one of the air distribution means on the side of the vehicle interior heat exchanger and the air distribution means on the side of the third vehicle interior heat exchanger. apparatus.