Vehicular air conditioning device

1. A vehicular air conditioning device comprising:

a compressor to compress a refrigerant;

an air flow passage through which air to be supplied to a vehicle interior flows;

a radiator to let the refrigerant radiate heat, thereby heating the air to be supplied from the air flow passage to the vehicle interior;

a heat absorber to let the refrigerant absorb heat, thereby cooling the air to be supplied from the air flow passage to the vehicle interior; and

a control device,

whereby the control device changes and executes a plurality of operation modes to condition the air of the vehicle interior,

wherein the control device calculates a heating temperature TH being a temperature of the air on a leeward side of the radiator and uses the heating temperature TH in control, and calculates the heating temperature TH using an estimation formula which differs depending on an operation mode,

wherein the control device performs a calculation of a first-order lag of a time constant Tau different depending on the operation mode to calculate the heating temperature TH.

2. The vehicular air conditioning device according to claim 1 , wherein the control device uses the heating temperature TH for calculation of an air volume ratio SW at which the air is to be passed through the radiator, and/or for changing of the operation modes.

3. The vehicular air conditioning device according to claim 1 , wherein the control device changes the time constant Tau of the first-order lag according to a volumetric air volume Ga of the air flowing into the air flow passage.

4. The vehicular air conditioning device according to claim 1 , wherein the control device calculates the heating temperature TH on the basis of a steady-state value TH 0 being a value of the heating temperature TH in a steady state, and the time constant Tau of the first-order lag.

5. The vehicular air conditioning device according to claim 4 , comprising:

an outdoor heat exchanger provided outside the vehicle interior,

wherein the control device has a dehumidifying and cooling mode to let the refrigerant discharged from the compressor flow from the radiator to the outdoor heat exchanger, let the refrigerant radiate heat in the radiator and the outdoor heat exchanger, decompress the refrigerant heat-radiated, and then let the refrigerant absorb heat in the heat absorber, and

wherein in the dehumidifying and cooling mode, the control device determines the steady-state value TH 0 on the basis of a saturation temperature THsatu of the refrigerant obtained from a refrigerant pressure of the radiator.

6. The vehicular air conditioning device according to claim 4 , comprising:

an outdoor heat exchanger provided outside the vehicle interior,

wherein the control device has a cooling mode to let the refrigerant discharged from the compressor flow from the radiator to the outdoor heat exchanger, let the refrigerant radiate heat in the outdoor heat exchanger, decompress the refrigerant heat-radiated, and then let the refrigerant absorb heat in the heat absorber, and

wherein in the cooling mode, the control device determines the steady-state value THO on the basis of an average value of refrigerant temperatures of an inlet and an outlet of the radiator.

7. The vehicular air conditioning device according to claim 4 , comprising:

a bypass device to let the refrigerant discharged from the compressor flow directly into the outdoor heat exchanger without flowing to the radiator,

wherein the control device has a maximum cooling mode to let the refrigerant discharged from the compressor flow into the outdoor heat exchanger by the bypass device and radiate heat therein, decompress the refrigerant heat-radiated, and then let the refrigerant absorb heat in the heat absorber, and

wherein in the maximum cooling mode, the control device determines the steady-state value TH 0 on the basis of the average value of the refrigerant temperatures of the inlet and outlet of the radiator.

8. The vehicular air conditioning device according to claim 4 , wherein the control device has a heating mode to let the refrigerant discharged from the compressor flow into the radiator and radiate heat therein, decompress the refrigerant heat-radiated, and then let the refrigerant absorb heat in the outdoor heat exchanger,

wherein in the heating mode, the control device corrects the saturation temperature THsatu of the refrigerant obtained from the refrigerant pressure of the radiator with a predetermined correction value to determine the steady-stage value TH 0 , and

wherein the control device determines the correction value from a subcool degree SC of the refrigerant in the radiator and the volumetric air volume Ga of the air flowing into the air flow passage, or the volumetric air volume Ga and an air volume ratio SW at which the air is to be passed through the radiator.

9. The vehicular air conditioning device according to claim 4 , comprising:

a bypass device to let the refrigerant discharged from the compressor flow directly into the outdoor heat exchanger without flowing to the radiator; and

an auxiliary heating device to let the air to be supplied from the air flow passage to the vehicle interior heat,

wherein the control device executes a dehumidifying and heating mode to let the refrigerant discharged from the compressor flow into the outdoor heat exchanger by the bypass device and radiate heat therein, decompress the refrigerant heat-radiated, then let the refrigerant absorb heat in the heat absorber, and let the auxiliary heating device generate heat, and

wherein in the dehumidifying and heating mode, the control device determines the steady-state value TH 0 on the basis of a temperature Tptc of the auxiliary heating device.

10. The vehicular air conditioning device according to claim 4 , wherein the control device has a dehumidifying and heating mode to let the refrigerant discharged from the compressor radiate heat in the radiator, decompress the refrigerant head-radiated, and then let the refrigerant absorb heat only in the heat absorber, or in the heat absorber and the outdoor heat exchanger, and

wherein in the dehumidifying and heating mode, the control device determines the steady-state value TH 0 on the basis of the saturation temperature THsatu of the refrigerant obtained from the refrigerant pressure of the radiator.

11. The vehicular air conditioning device according to claim 4 , wherein the control device determines the steady-stage value TH 0 on the basis of the saturation temperature THsatu of the refrigerant obtained from the refrigerant pressure of the radiator, or the average value of the refrigerant temperatures of the inlet and outlet of the radiator during an operation stop.

12. The vehicular air conditioning device according to claim 3 , wherein the control device calculates the heating temperature TH on the basis of a steady-state value TH 0 being a value of the heating temperature TH in a steady state, and the time constant Tau of the first-order lag.

13. The vehicular air conditioning device according to claim 5 , comprising:

an outdoor heat exchanger provided outside the vehicle interior,

wherein the control device has a cooling mode to let the refrigerant discharged from the compressor flow from the radiator to the outdoor heat exchanger, let the refrigerant radiate heat in the outdoor heat exchanger, decompress the refrigerant heat-radiated, and then let the refrigerant absorb heat in the heat absorber, and

wherein in the cooling mode, the control device determines the steady-state value TH 0 on the basis of an average value of refrigerant temperatures of an inlet and an outlet of the radiator.

14. The vehicular air conditioning device according to claim 6 , further comprising:

a bypass device to let the refrigerant discharged from the compressor flow directly into the outdoor heat exchanger without flowing to the radiator,

wherein the control device has a maximum cooling mode to let the refrigerant discharged from the compressor flow into the outdoor heat exchanger by the bypass device and radiate heat therein, decompress the refrigerant heat-radiated, and then let the refrigerant absorb heat in the heat absorber, and

wherein in the maximum cooling mode, the control device determines the steady-state value TH 0 on the basis of the average value of the refrigerant temperatures of the inlet and outlet of the radiator.

15. The vehicular air conditioning device according to claim 7 , wherein the control device has a heating mode to let the refrigerant discharged from the compressor flow into the radiator and radiate heat therein, decompress the refrigerant heat-radiated, and then let the refrigerant absorb heat in the outdoor heat exchanger,

wherein in the heating mode, the control device corrects the saturation temperature THsatu of the refrigerant obtained from the refrigerant pressure of the radiator with a predetermined correction value to determine the steady-stage value TH 0 , and

wherein the control device determines the correction value from a subcool degree SC of the refrigerant in the radiator and the volumetric air volume Ga of the air flowing into the air flow passage, or the volumetric air volume Ga and an air volume ratio SW at which the air is to be passed through the radiator.

16. The vehicular air conditioning device according to claim 8 , comprising:

a bypass device to let the refrigerant discharged from the compressor flow directly into the outdoor heat exchanger without flowing to the radiator; and

an auxiliary heating device to let the air to be supplied from the air flow passage to the vehicle interior heat,

wherein the control device executes a dehumidifying and heating mode to let the refrigerant discharged from the compressor flow into the outdoor heat exchanger by the bypass device and radiate heat therein, decompress the refrigerant heat-radiated, then let the refrigerant absorb heat in the heat absorber, and let the auxiliary heating device generate heat, and

wherein in the dehumidifying and heating mode, the control device determines the steady-state value TH 0 on the basis of a temperature Tptc of the auxiliary heating device.

17. The vehicular air conditioning device according to claim 8 , wherein the control device has a dehumidifying and heating mode to let the refrigerant discharged from the compressor radiate heat in the radiator, decompress the refrigerant head-radiated, and then let the refrigerant absorb heat only in the heat absorber, or in the heat absorber and the outdoor heat exchanger, and

wherein in the dehumidifying and heating mode, the control device determines the steady-state value TH 0 on the basis of the saturation temperature THsatu of the refrigerant obtained from the refrigerant pressure of the radiator.

18. The vehicular air conditioning device according to claim 10 , wherein the control device determines the steady-stage value TH 0 on the basis of the saturation temperature THsatu of the refrigerant obtained from the refrigerant pressure of the radiator, or the average value of the refrigerant temperatures of the inlet and outlet of the radiator during an operation stop.