JP2011068151A - Vehicular air-conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular air-conditioner capable of obtaining the effect of improving the fuel economy even in an area with less cold season. <P>SOLUTION: The vehicular air-conditioner includes a heater core for heating blown air in a cabin with engine cooling water as a heat source, a PTC heater for supporting the heating by the heater core, and an air-conditioning control device for outputting the operation request signal to an engine when the temperature of the cooling water is lower than the threshold. By setting the threshold to be lower than that when the PTC heater is stopped during the operation of the PTC heater, the fuel consumption is improved. To prevent any failure of the PTC heater, the operational time of the PTC heater per unit run is limited. If the use of the PTC heater is limited to a cold season at the temperature of equal to or lower than 10°C in order to prevent any failure of the PTC heater, the operational time of the PTC heater is reduced in an area with less cold season, and the effect of improving the fuel economy cannot be obtained. However, the use of the PTC heater need not be limited to a cold season, and the effect of improving the fuel economy can be obtained even in an area of less cold season. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a vehicle air conditioner.

  2. Description of the Related Art Conventionally, a vehicle air conditioner equipped with a heater core that is mounted on a vehicle that automatically stops an engine according to a traveling state, such as a hybrid vehicle or an idling stop vehicle, and that heats blown air into the vehicle interior using engine cooling water as a heat source. However, even if the engine is stopped depending on the running state, etc., there are some that require engine operation for air conditioning if the temperature of the engine cooling water is lower than a predetermined temperature (threshold). (For example, refer to Patent Document 1).

  In such a vehicle air conditioner, if the engine is operated for air conditioning when the engine is stopped, there is a problem in that fuel consumption is deteriorated. Therefore, in the technique described in Patent Document 1, the operating temperature of the engine when the electric heater is operated is set by setting the predetermined temperature when the electric heater is operated lower than the predetermined temperature when the electric heater is stopped. The fuel consumption is improved by making it lower than when the electric heater is stopped.

JP 2008-174042 A

  By the way, the electric heater has a product life, and if the total operation time of the electric heater exceeds a predetermined operation limit time, there is a high possibility that the electric heater will fail. Therefore, in order not to cause a failure of the electric heater during a predetermined period such as a durable life period of the vehicle, the electric heater is not operated so that the total operation time of the electric heater within the predetermined period does not exceed the operation limit time. It is conceivable to limit use.

  And as a means to restrict | limit the use of this electric heater, the means to provide the use restriction by external temperature can be considered. That is, a means is considered that operates the electric heater only when the outside air temperature is lower than a predetermined temperature (reference temperature), and does not operate the electric heater when the outside air temperature is higher than the predetermined temperature. At this time, with respect to the reference temperature, since the vehicle may run or be sold in any region of the world, it is necessary to set a reference temperature that is unified throughout the world. Furthermore, in order to use a reference temperature that is unified throughout the world, it is required to set the reference temperature with reference to the cold region so that no failure occurs in the cold region where the conditions are most severe.

  However, if the standard temperature is set globally based on the cold region, the electric heater will operate less frequently in regions where the outside air temperature is lower than the reference temperature and there are few cold periods as described below. End up.

  Here, FIG. 8 shows monthly average temperatures in Moscow and Rome as examples of cities in the world. For example, assuming Moscow, which is a cold region among the regions of the world, the reference temperature is examined so that the electric heater does not fail during the durable years of the automobile.

  If the reference temperature is set to 12 ° C, the electric heater is activated when the temperature is 12 ° C or lower, the car has a durable life of 15 years, and one-way one-way operation is reciprocated every day. Is 8000 hours, and the operating time in Moscow is estimated as follows. That is, since the month of 12 ° C or less in Moscow is 9 months from September to May, 9 months × 30 days × 15 years × 1 hour × 2 times = 8100 hours, exceeding 8000 hours, so 15 years The electric heater will be broken.

  Therefore, if the reference temperature is set to 10 ° C, the month when the temperature falls below 10 ° C in Moscow is 8 months from September to April, so 8 months x 30 days x 15 years x 1 hour x 2 times = 7200 hours. It is estimated that the electric heater will not break for 15 years. By the way, when the outside air temperature is 10 ° C. or less, as described later, when the target outlet temperature TAO is calculated based on the outside air temperature and the outlet port mode is selected based on the calculated TAO, the FOOT mode is set. Setting the reference temperature to 10 ° C. is equivalent to limiting the operating condition of the electric heater in the FOOT mode.

  However, when the reference temperature is set to 10 ° C., as shown in FIG. 8, in Rome, the month in which the temperature is 10 ° C. or less is only three months from December to February, so the operation time of the electric heater in Rome is estimated. 3 months × 30 days × 15 years × 1 hour × 2 times = 2700 hours.

  For this reason, as described in Patent Document 1, in the vehicle air conditioner that improves the fuel consumption by lowering the frequency of the operation request of the engine when the electric heater is operated than when the electric heater is stopped, as described above, Setting restrictions on the use of electric heaters based on the outside air temperature based on the cold region of the world causes a problem that the effect of improving fuel efficiency cannot be obtained in regions where the cold season is low, since the frequency of operation of the electric heater is low .

  Such a problem is not limited to a vehicle air conditioner that includes a heating device that heats blown air into the vehicle interior using the engine as a heat source, but is mounted on a fuel cell vehicle and uses the coolant of the fuel cell as a heat source. Vehicle air conditioner equipped with a heating device that heats blown air to the vehicle, and vehicle air conditioner equipped with a heating device that is mounted on an electric vehicle and that heats the blown air into the vehicle interior using hot water heated by an electric hot water heater The same applies to the apparatus. That is, in the vehicle air conditioner that achieves an energy saving effect by lowering the frequency of the operation request of the fuel cell and the electric water heater when the electric heater is operating than when the electric heater is stopped, When the use restriction of the electric heater is provided, in a region where there are few cold periods, the electric heater is operated less frequently, so that the energy saving effect cannot be obtained.

  An object of this invention is to provide the vehicle air conditioner from which the effect of energy saving is acquired also in an area with few cold periods in view of the said point.

  First, in the first aspect of the invention, the control means (50) is configured such that the operating frequency of the temperature raising means (EG) during the operation of the electric heater is the output condition of the operation request signal to the temperature raising means (EG). It is assumed that an output condition set to be lower than when the electric heater is stopped is used. This saves energy and saves energy when the temperature raising means is operated, compared with the case where the temperature raising means (EG) is operated at the same frequency as when the electric heater is stopped. I am trying.

And in order to achieve the said objective, in invention of Claim 1, the operation time of the electric heater per driving | running | working until it stops after the vehicle control system which controls the driving drive source of a vehicle starts is measured. Measuring means (50a),
The control means (50) determines the operation of the electric heater (15) according to the necessity of heating by the electric heater (15), and the operation time measured by the measurement means (50a) has passed a predetermined time Further, it is characterized in that the stop of the electric heater (15) is determined.

  According to this, since the operation time of the electric heater per one run is limited, the total operation time of the electric heater in a predetermined period such as a durable life period of the vehicle can be suppressed, and the risk that the electric heater breaks down. Can be reduced.

  Further, in the present invention, the use of the electric heater by the outside air temperature is set by setting the standard temperature that is standardized all over the world based on the cold region of the world described above by limiting the operation time of the electric heater per one run. Limits can be made unnecessary. Therefore, according to the present invention, the use frequency of the electric heater can be increased in an area where the cold period is small, as compared with the case where the use restriction of the electric heater due to the outside air temperature is provided. However, a sufficient operating time of the electric heater can be secured, and the above-described energy saving effect can be obtained.

  The present invention eliminates the use restriction due to the outside temperature to prevent the occurrence of failure due to the life of the electric heater within a predetermined period, but in order to determine the necessity of heating the electric heater, It is not unnecessary to compare the outside air temperature with the reference temperature. That is, in the present invention, the electric heater may be stopped when the outside air temperature is so high that there is no need for heating by the electric heater.

  As an example of determining the operation of the electric heater (15) according to the necessity of heating by the electric heater (15) in the invention described in claim 1, for example, as in claim 2, the temperature of the heat medium is predetermined. For example, determining the operation of the electric heater when the temperature is lower.

In the first aspect of the present invention, as in the third aspect, the control means (50) is in operation of the electric heater (15) and the temperature of the heat medium is higher than a predetermined temperature. , The stop of the electric heater (15) is determined, and the measurement by the measuring means (50a) is temporarily stopped,
When the temperature of the heat medium falls from a temperature higher than the predetermined temperature to a temperature lower than the predetermined temperature, the operation of the electric heater (15) is determined and the measurement by the measuring means (50a) is resumed. Is preferred.

  When the temperature raising means is activated for a purpose other than air conditioning and the temperature of the heat medium is high, a sufficient feeling of heating can be obtained even if the electric heater is stopped. Therefore, the electric heater is stopped as in the present invention. May be. At this time, by temporarily stopping the measurement by the measurement means and restarting the measurement by the measurement means when the operation of the electric heater is started again, a predetermined time elapses after the vehicle control system is started. The time until the electric heater is stopped can be lengthened.

In the first aspect of the invention, as in the fourth aspect, the control means (50) is the warm air adjusted by the temperature adjusting means (19) while the electric heater (15) is in operation. When the ratio is smaller than the predetermined ratio, the stop of the electric heater (15) is determined and the measurement by the measuring means (50a) is temporarily stopped.
When the warm air rate increases from a rate smaller than the predetermined rate to a rate higher than the predetermined rate, the operation of the electric heater (15) is determined and the measurement by the measuring means (50a) is resumed. It is preferable.

  If the temperature riser is activated for a purpose other than air conditioning and the temperature of the heat medium rises, and the required air temperature can be obtained without mixing warm air with air mix control, the electric heater is stopped. In addition, since a sufficient heating feeling can be obtained, the electric heater may be stopped as in the present invention. At this time, by temporarily stopping the measurement by the measurement means and restarting the measurement by the measurement means when the operation of the electric heater is started again, a predetermined time elapses after the vehicle control system is started. The time until the electric heater is stopped can be lengthened.

  In the first aspect of the present invention, as described in the fifth aspect, the control means (50) is configured to output the operation request signal when the temperature of the heat medium is lower than a threshold value. While outputting an operation request signal, an output condition in which a threshold value when the electric heater (15) is operated is set lower than a threshold value when the electric heater is stopped can be used. Thereby, the operating frequency of the temperature raising means (EG) when the electric heater is operating can be made lower than when the electric heater is stopped.

  In the invention described in claim 6, the heat exchanger for heating (14) uses cooling water of the engine (EG) as a heat medium, and the temperature raising means is the engine (EG). It is said. Thus, it is preferable to apply the invention of Claims 1-5 to the vehicle air conditioner which uses the heating heat exchanger which heat-exchanges engine cooling water and air.

  In addition, the code | symbol in the bracket | parenthesis of each means described in this column and the claim shows the correspondence with the specific means as described in embodiment mentioned later.

It is a block diagram of the vehicle air conditioner in 1st Embodiment of this invention. It is a block diagram of the electric control part of the vehicle air conditioner of FIG. It is a block diagram of the electric heater in FIG. It is a flowchart which shows the control processing of the vehicle air conditioner of FIG. It is a flowchart which shows the detail of step S10 of FIG. It is a flowchart which shows the detail of step S11 of FIG. It is a flowchart which shows the detail of step S12 of FIG. It is a graph which shows the average temperature every month in Moscow and Rome for demonstrating a subject.

(First embodiment)
FIG. 1 shows an overall configuration of a vehicle air conditioner according to the present embodiment, and FIG. 2 shows a configuration of an electric control unit of the vehicle air conditioner. The vehicle air conditioner of the present embodiment is mounted on a hybrid vehicle that obtains driving force for vehicle traveling from an engine (internal combustion engine) EG and a traveling electric motor.

  The hybrid vehicle according to this embodiment operates or stops the engine EG according to the travel load of the vehicle, obtains driving force from both the engine EG and the travel electric motor, and stops the engine. It is possible to switch a traveling state in which traveling is performed by obtaining a driving force only from the traveling electric motor. Thereby, the vehicle fuel consumption is improved with respect to the normal vehicle which obtains the driving force for vehicle travel only from the engine EG.

  The vehicle air conditioner 1 includes an indoor air conditioning unit 10 shown in FIG. 1 and an air conditioning control device 50 shown in FIG. 2 as control means of the present invention.

  The indoor air conditioning unit 10 is disposed inside the instrument panel (instrument panel) at the foremost part of the vehicle interior, and includes a blower 12, an evaporator 13, a heater core 14, a PTC heater 15 and the like in a casing 11 that forms an outer shell thereof. It is what was contained.

  The casing 11 forms an air passage for blown air that is blown into the passenger compartment, and is formed of a resin (for example, polypropylene) that has a certain degree of elasticity and is excellent in strength. On the most upstream side of the blown air flow in the casing 11, an inside / outside air switching box 20 for switching and introducing inside air (vehicle compartment air) and outside air (vehicle compartment outside air) is disposed.

  More specifically, the inside / outside air switching box 20 is formed with an inside air introduction port 21 for introducing inside air into the casing 11 and an outside air introduction port 22 for introducing outside air. Further, inside / outside air switching box 20 is an inside / outside air switching door that continuously adjusts the opening areas of inside air introduction port 21 and outside air introduction port 22 to change the air volume ratio between the air volume of the inside air and the air volume of the outside air. 23 is arranged.

  Therefore, the inside / outside air switching door 23 constitutes an air volume ratio changing means for switching the suction port mode for changing the air volume ratio between the air volume of the inside air introduced into the casing 11 and the air volume of the outside air. More specifically, the inside / outside air switching door 23 is driven by an electric actuator 62 for the inside / outside air switching door 23, and the operation of the electric actuator 62 is controlled by a control signal output from the air conditioning controller 50. The

  As the suction port mode, the inside air introduction port 21 is fully opened and the outside air introduction port 22 is fully closed to introduce the inside air into the casing 11. The inside air introduction port 21 is fully closed and the outside air introduction port 22 is fully closed. The outside air mode in which the outside air is introduced into the casing 11 with the valve fully open, and the opening areas of the inside air introduction port 21 and the outside air introduction port 22 are continuously adjusted between the inside air mode and the outside air mode. There is an internal / external air mixing mode that continuously changes the introduction ratio.

  A blower 12 that blows air sucked through the inside / outside air switching box 20 toward the vehicle interior is disposed on the downstream side of the inside / outside air switching box 20. The blower 12 is an electric blower that drives a centrifugal multiblade fan (sirocco fan) with an electric motor, and the number of rotations (the amount of blown air) is controlled by a control voltage output from the air conditioning controller 50.

  An evaporator 13 is disposed on the downstream side of the air flow of the blower 12. The evaporator 13 is a cooling heat exchanger that cools the blown air by exchanging heat between the refrigerant flowing through the evaporator 13 and the blown air. The evaporator 13 constitutes a refrigeration cycle 30 together with a compressor (compressor) 31, a condenser 32, a gas-liquid separator 33, an expansion valve 34, and the like.

  The compressor 31 is disposed in the engine room, sucks the refrigerant in the refrigeration cycle 30, compresses and discharges it, and drives the fixed capacity type compression mechanism 31a having a fixed discharge capacity by the electric motor 31b. It is configured as an electric compressor. The electric motor 31 b is an AC motor whose operation (number of rotations) is controlled by the AC voltage output from the inverter 61. Further, the inverter 61 outputs an AC voltage having a frequency corresponding to a control signal output from the air conditioning control device 50 described later. And the refrigerant | coolant discharge capability of the compressor 31 is changed by this rotation speed control. Therefore, the electric motor 31 b constitutes a discharge capacity changing unit of the compressor 31.

  The condenser 32 is disposed in the engine room, and exchanges heat between the refrigerant circulating in the interior and the outside air (outside air) blown from the blower fan 35 as an outdoor blower, so that the compressed refrigerant is Condensed liquid. The blower fan 35 is an electric blower in which the operating rate, that is, the rotation speed (the amount of blown air) is controlled by the control voltage output from the air conditioning control device 50.

  The gas-liquid separator 33 gas-liquid separates the condensed and liquefied refrigerant and flows only the liquid refrigerant downstream. The expansion valve 34 is a decompression unit that decompresses and expands the liquid refrigerant. The evaporator 13 evaporates the refrigerant expanded under reduced pressure by heat exchange between the refrigerant and the blown air.

  Further, in the casing 11, on the downstream side of the air flow of the evaporator 13, an air passage such as a cooling cold air passage 16 and a cold air bypass passage 17 for flowing air after passing through the evaporator 13, and the heating cold air passage 16 and the cold air are provided. A mixing space 18 for mixing the air that has flowed out of the bypass passage 17 is formed.

  A heater core 14 and a PTC heater 15 as heating means for heating the air that has passed through the evaporator 13 are arranged in this order in the cooling air passage 16 for heating in the air flow direction. The heater core 14 is a heating means for main heating, and the PTC heater 15 is a heating means for auxiliary heating that assists heating by the heater core 14. Therefore, the heating cool air passage 16 constitutes a warm air passage through which the warm air blown from the heater core 14 flows.

  The heater core 14 is a heat exchanger for heating that heats the air that has passed through the evaporator 13 by exchanging heat between the cooling water of the engine EG that outputs vehicle driving force and the air that has passed through the evaporator 13.

  Specifically, a cooling water flow path 41 is provided between the heater core 14 and the engine EG, and the cooling water circuit 40 is configured in which the cooling water circulates between the heater core 14 and the engine EG. The cooling water circuit 40 is provided with an electric water pump 42 for circulating the cooling water. The electric water pump 42 is an electric water pump whose rotation speed (cooling water circulation amount) is controlled by a control voltage output from the air conditioning control device 50.

  The PTC heater 15 is an electric heater that has a PTC element (positive characteristic thermistor), generates heat when electric power is supplied to the PTC element, and heats air after passing through the heater core 14.

  Here, FIG. 3 shows an electrical configuration of the PTC heater 15 of the present embodiment. In the present embodiment, a plurality of, for example, three PTC heaters 15a, 15b, and 15c are used as the PTC heater 15. The air conditioning controller 50 controls ON / OFF of switch elements SW1, SW2, and SW3 provided for the PTC elements h1, h2, and h3 of the first PTC heater 15a, the second PTC heater 15b, and the third PTC heater 15c. Thus, the energization / non-energization of each PTC heater 15a, 15b, 15c is controlled. The air conditioning control device 50 changes the number of PTC heaters 15 to be energized, thereby controlling the heating capacity of the plurality of PTC heaters 15 as a whole.

  On the other hand, the cold air bypass passage 17 is an air passage for guiding the air after passing through the evaporator 13 to the mixing space 18 without passing through the heater core 14 and the PTC heater 15, and constitutes a cold air passage through which the cold air flows. Yes. Accordingly, the temperature of the blown air mixed in the mixing space 18 varies depending on the air volume ratio of the air passing through the heating cool air passage 16 and the air passing through the cold air bypass passage 17.

  Therefore, in the present embodiment, the amount of cold air that flows into the heating cold air passage 16 and the cold air bypass passage 17 on the downstream side of the air flow of the evaporator 13 and on the inlet side of the heating cold air passage 16 and the cold air bypass passage 17. An air mix door 19 that continuously changes the ratio is disposed.

  Therefore, the air mix door 19 constitutes a temperature adjusting means for adjusting the air temperature in the mixing space 18 (the temperature of the blown air blown into the vehicle interior). More specifically, the air mix door 19 is driven by an electric actuator 63 for the air mix door, and the operation of the electric actuator 63 is controlled by a control signal output from the air conditioning controller 50.

  Furthermore, blower outlets 24 to 26 that blow out the blown air whose temperature has been adjusted from the mixing space 18 to the vehicle interior that is the air-conditioning target space are disposed in the most downstream portion of the blown air flow of the casing 11. Specifically, the air outlets 24 to 26 include a face air outlet 24 that blows air-conditioned air toward the upper body of the passenger in the vehicle interior, a foot air outlet 25 that blows air-conditioned air toward the feet of the passenger, and the front of the vehicle. A defroster outlet 26 that blows air-conditioned air toward the inner side surface of the window glass is provided.

  Further, on the upstream side of the air flow of the face air outlet 24, the foot air outlet 25, and the defroster air outlet 26, the face door 24a for adjusting the opening area of the face air outlet 24 and the opening area of the foot air outlet 25 are adjusted. The defroster door 26a which adjusts the opening area of the foot door 25a to perform and the defroster blower outlet 26 is arrange | positioned.

  The face door 24a, foot door 25a, and defroster door 26a constitute an outlet mode switching means for switching an outlet mode, and an electric actuator 64 for driving the outlet mode door via a link mechanism (not shown). It is linked to and rotated in conjunction with it. The operation of the electric actuator 64 is also controlled by a control signal output from the air conditioning controller 50.

  Further, as the air outlet mode, the face air outlet 24 is fully opened and air is blown out from the face air outlet 24 toward the upper body of the passenger in the vehicle. Both the face air outlet 24 and the foot air outlet 25 are opened. A bi-level mode that blows air toward the upper body and feet of passengers in the passenger compartment, a foot mode in which the foot blower outlet 25 is fully opened and the defroster blower opening 26 is opened by a small opening, and air is mainly blown from the foot blower outlet 25. In addition, there is a foot defroster mode in which the foot outlet 25 and the defroster outlet 26 are opened to the same extent and air is blown out from both the foot outlet 25 and the defroster outlet 26.

  Next, the electric control unit of the present embodiment will be described with reference to FIG. The air conditioning control device 50 is composed of a well-known microcomputer including a CPU, a memory such as a ROM and a RAM, and its peripheral circuits, and performs various calculations and processing based on an air conditioning control program stored in the ROM, and outputs it. The blower 12 connected to the side, the inverter 61 for the electric motor 31b of the compressor 31, the blower fan 35, various electric actuators 62, 63, 64, the first PTC heater 15a, the second PTC heater 15b, the third PTC heater 15c, the electric water The operation of the pump 42 and the like is controlled.

  Further, on the input side of the air-conditioning control device 50, an inside air sensor 51 that detects the vehicle interior temperature Tr, an outside air sensor 52 (outside air temperature detection means) that detects the outside air temperature Tam, and a solar radiation sensor that detects the amount of solar radiation Ts in the vehicle interior. 53, a discharge temperature sensor 54 (discharge temperature detection means) for detecting the compressor 31 discharge refrigerant temperature Td, a discharge pressure sensor 55 (discharge pressure detection means) for detecting the compressor 31 discharge refrigerant pressure Pd, and an outlet from the evaporator 13 An evaporator temperature sensor 56 (evaporator temperature detection means) that detects an air temperature (evaporator temperature) TE, an intake temperature sensor 57 that detects a temperature Tsi of refrigerant sucked into the compressor 31, and an engine coolant temperature TW A detection signal of a sensor group such as the cooling water temperature sensor 58 is input.

  Note that the evaporator temperature sensor 56 of the present embodiment specifically detects the heat exchange fin temperature of the evaporator 13. Of course, as the evaporator temperature sensor 56, temperature detection means for detecting the temperature of other parts of the evaporator 13 may be adopted, or temperature detection means for directly detecting the temperature of the refrigerant itself flowing through the evaporator 13 may be used. It may be adopted.

  Further, operation signals from various air conditioning operation switches provided on the operation panel 60 disposed near the instrument panel in the front part of the vehicle interior are input to the input side of the air conditioning control device 50. As various air conditioning operation switches provided on the operation panel 60, specifically, an operation switch (not shown) of the vehicle air conditioner 1 and an air conditioner on / off (specifically, the compressor 31 is on / off). Air conditioner switch 60a for switching, auto switch 60b for setting / releasing automatic control of the vehicle air conditioner 1, operation mode switch (not shown), suction port mode switch (not shown) for switching the suction port mode, blowing Air outlet mode switch (not shown) for switching the outlet mode, air volume setting switch (not shown) of the blower 12, vehicle interior temperature setting switch 60c for setting the vehicle interior temperature, and a command for giving priority to power saving of the refrigeration cycle An economy switch 60d for output is provided.

  In addition, the air conditioning control device 50 includes a timer 50 a as a measuring unit that measures the operation time of the PTC heater 15.

  Further, the air conditioning control device 50 is electrically connected to an engine control device 70 that controls the operation of the engine EG, and the air conditioning control device 50 and the engine control device 70 are configured to be capable of electrical communication with each other. Thereby, based on the detection signal or operation signal input into one control apparatus, the other control apparatus can also control the operation | movement of the various apparatuses connected to the output side. For example, the engine EG can be operated by the air conditioning control device 50 outputting an operation request signal for the engine EG to the engine control device 70.

  Next, the operation of this embodiment in the above configuration will be described with reference to FIG. FIG. 4 is a flowchart showing a control process of the vehicle air conditioner 1 of the present embodiment. The control process of FIG. 4 is started when the ignition switch (IG) is turned from OFF to ON and the power supply of the air conditioning control device 50 is automatically turned on. Even if the operation switch of the air conditioning control device 50 is OFF, the air conditioning control device 50 executes the control process of FIG. 4 and does not output a control signal in step S13 or outputs a stop signal, etc. The device 1 is not activated. In addition, each step S1-S14 in FIG. 4 is corresponded to each function means S1-S14 which the air-conditioning control apparatus 50 has.

  First, in step S1, initialization of a flag, a timer, and the like, initial alignment of a stepping motor constituting the electric actuator described above, and the like are performed.

  In the next step S2, the operation signal of the operation panel 60 is read and the process proceeds to step S3. Specific operation signals include a vehicle interior set temperature Tset set by the vehicle interior temperature setting switch 60c, an air outlet mode selection signal, an air inlet mode selection signal, an air volume setting signal of the blower 12, and the like.

In step S3, a vehicle environmental state signal used for air conditioning control, that is, a detection signal from the above-described sensor groups 51 to 58, etc. is read, and the process proceeds to step S4. In step S4, the target blowing temperature TAO of the vehicle compartment blowing air is calculated. The target blowing temperature TAO is calculated by the following formula F1.
TAO = Kset × Tset−Kr × Tr−Kam × Tam−Ks × Ts + C (F1)
Here, Tset is the vehicle interior temperature set by the vehicle interior temperature setting switch 60c, Tr is the vehicle interior temperature (internal air temperature) detected by the internal air sensor 51, Tam is the external air temperature detected by the external air sensor 52, Ts. Is the amount of solar radiation detected by the solar radiation sensor 53. Kset, Kr, Kam, Ks are control gains, and C is a correction constant.

  In subsequent steps S5 to S12, control states of various devices connected to the air conditioning control device 50 are determined.

  First, in step S5, the target opening degree SW of the air mix door 19 is calculated based on the TAO, the air temperature TE blown from the evaporator 13 detected by the evaporator temperature sensor 56, and the hot air temperature TWD before the air mix. To do.

Specifically, the target opening degree SW can be calculated by the following formula F2-1.
SW = [{TAO− (TE + 2)} / {TWD− (TE + 2)}] × 100 (%) (F2-1)
Here, the hot air temperature TWD before air mixing is a value determined according to the heating capacity of the heating means (heater core 14 and PTC heater 15) disposed in the cold air passage 16 for heating. Can be calculated by the following formula F2-2.
TWD = TW × 0.8 + TE × 0.2 + ΔTptc (F2-2)
Here, TE is the temperature of air blown from the evaporator 13 detected by the evaporator temperature sensor 56, TW is the engine coolant temperature detected by the coolant temperature sensor 58, and ΔTptc is the temperature of the air blown by the operation of the PTC heater 15. The amount of increase. Further, 0.8 is an example of the heat exchange efficiency α of the heater core 14, and 0.2 is an example of the contribution β of the blown air temperature TE from the evaporator 13 to the blown air temperature from the heater core 14.

This blowout temperature rise amount ΔTptc is a temperature rise amount contributed by the operation of the PTC heater 15 in the temperature (blowing temperature) of the conditioned air blown from the blowout port into the vehicle interior. This blowing temperature rise amount ΔTptc is the power consumption W (Kw) of the PTC heater 15, the air density ρ (kg / m ³ ), the air specific heat Cp, and the PTC passage air amount Va (m ³ / h), it can be calculated by Formula F2-3.
ΔTptc = W / ρ / Cp / Va × 3600 (F2-3)
Here, as the power consumption W of the PTC heater 15, a value obtained by correcting the rated power consumption of the PTC heater 15 based on the temperature of the air flowing into the PTC heater 15 and the temperature characteristics of the PTC element can be used. .

As the PTC passage air volume Va, the air mix opening SW_OLD (%) calculated in the previous step S5 is calculated with respect to the air flow calculated by the formula F2-4, that is, the blower air volume, instead of simply using the blower air volume. Use what you consider.
Va (m ³ / h) = Blower air volume (m ³ / h) × f (SW_OLD / 100) (F2-4)
Here, as f (SW_OLD / 100), when SW_OLD (%) is 10 or more and 100 or less, the result calculated by SW_OLD / 100 is used, and when SW_OLD (%) <10, f (SW_OLD / 100) Is 0.1 and SW_OLD (%)> 100, f (SW_OLD / 100) is set to 1 (see the relationship diagram between f (SW / 100) and SW described in step S31 described later).

  In this way, the blowout temperature rise amount ΔTptc can be calculated so as not to deviate from the blowout temperature rise amount due to the actual operation of the PTC heater 15. Note that ΔTptc is updated every second with a time constant of 30 seconds. When step S5 is executed for the first time, the calculation of Formula F2-4 is performed with the previous air mix opening SW_OLD = 100%.

  SW = 0 (%) is the maximum cooling position of the air mix door 19, and the cold air bypass passage 17 is fully opened and the heating cold air passage 16 is fully closed. On the other hand, SW = 100 (%) is the maximum heating position of the air mix door 19, and the cold air bypass passage 17 is fully closed and the heating cold air passage 16 is fully opened.

  In step S6, the target air volume of the air blown by the blower 12 is determined. Specifically, the blower motor voltage to be applied to the electric motor is determined with reference to a control map stored in advance in the air conditioning control device 50 based on the TAO determined in step S4.

  Specifically, in this embodiment, the blower motor voltage is set to a high voltage near the maximum value in the extremely low temperature range (maximum cooling range) and the extremely high temperature range (maximum heating range) of TAO, and the air volume of the blower 12 is near the maximum air volume. To control. Further, when TAO rises from the extremely low temperature region toward the intermediate temperature region, the blower motor voltage is decreased according to the increase in TAO, and the air volume of the blower 12 is decreased.

  Further, when TAO decreases from the extremely high temperature range toward the intermediate temperature range, the blower motor voltage is decreased according to the decrease in TAO, and the air volume of the blower 12 is decreased. When TAO enters a predetermined intermediate temperature range, the blower motor voltage is set to the minimum value and the air volume of the blower 12 is set to the minimum value.

  In step S7, the suction port mode, that is, the switching state of the inside / outside air switching box 20 is determined. This inlet mode is also determined based on TAO with reference to a control map stored in advance in the air conditioning controller 50. In the present embodiment, priority is given mainly to the outside air mode for introducing outside air. However, the inside air mode for introducing inside air is selected when TAO is in a very low temperature range and high cooling performance is desired. Further, an exhaust gas concentration detecting means for detecting the exhaust gas concentration of the outside air may be provided, and the inside air mode may be selected when the exhaust gas concentration becomes equal to or higher than a predetermined reference concentration.

  In step S8, the outlet mode is determined. This air outlet mode is also determined with reference to a control map stored in advance in the air conditioning control device 50 based on TAO. In this embodiment, as the TAO rises from the low temperature range to the high temperature range, the outlet mode is sequentially switched from the foot mode to the bi-level mode to the face mode.

  Accordingly, the face mode is mainly selected in the summer, the bi-level mode is mainly selected in the spring and autumn, and the foot mode is mainly selected in the winter. Furthermore, when there is a high possibility that fogging will occur on the window glass from the detection value of the humidity sensor, the foot defroster mode or the defroster mode may be selected.

  In step S9, the refrigerant discharge capacity (specifically, the rotational speed) of the compressor 31 is determined. The basic method for determining the rotational speed of the compressor 31 of the present embodiment is as follows. For example, the target blowing temperature TEO of the blowing air temperature TE from the evaporator 13 is determined with reference to a control map stored in advance in the air conditioning control device 50 based on the TAO determined in step S4.

  Further, a deviation En (TEO-TE) between the target blowing temperature TEO and the blowing air temperature TE is calculated, and the deviation change rate obtained by subtracting the deviation En-1 calculated last time from the deviation En calculated this time. Based on fuzzy reasoning based on membership functions and rules stored in advance in the air-conditioning control device 50 using Edot (En− (En−1)), the rotation with respect to the previous compressor speed fCn−1 The number change amount ΔfC is obtained. Then, a value obtained by adding the rotational speed change amount ΔfC to the previous compressor rotational speed fCn−1 is set as the current compressor rotational speed fCn.

  In step S10, the number of operating PTC heaters 15 is determined and the operating time of the PTC heater 15 is limited. FIG. 5 is a flowchart showing details of step S10. Hereinafter, the detailed contents of step S10 will be described with reference to FIG.

  First, in step S20, it is determined whether or not the total operating time Tsum of the PTC heater 15 has passed 43 minutes as a predetermined time limit.

  Here, the total operating time Tsum of the PTC heater 15 is the total operating time of the PTC heater 15 per one run. Furthermore, per run means the period from when the IG is turned off to on and then off again, and has the same meaning as per trip per vehicle use period. The measurement of the operation time is executed by steps S25 to S27 described later.

  The time limit is 12 months × 30 days × 15 years × (PTC heater operation time) × 2 times = (total of PTC heater operation time). The total (total operation time) is calculated so as not to exceed the operation limit time of the PTC heater 15.

  This calculation formula is the same as the formula described in the section of the problem to be solved by the invention, assuming that the durable life period of the car is 15 years, and the driving of one hour one-way is reciprocated every day. Yes. However, in this embodiment, since the PTC heater can be used all year without any restriction due to the outside temperature, the number of months of use is calculated as 12 months. In the present embodiment, the operation limit time of the PTC heater is set to 8000 hours, and the total operation time is estimated. As a result, if the time limit is 43 minutes, 12 months × 30 days × 15 years × (43 minutes / 60) X 2 times = 7668 hours, and 8000 hours are not exceeded, so the time limit is set to 43 minutes.

  At this time, if the total time Tsum has passed 43 minutes, a YES determination is made, the process proceeds to step S24, and the number of operating PTC heaters 15 is determined to be zero. On the other hand, if the total time Tsum has not passed 43 minutes, a NO determination is made and the process proceeds to step S21. Thereby, the operation time of the PTC heater 15 per one run is limited to 45 minutes. Therefore, step S20 constitutes a limiting means for limiting the operating time of the PTC heater 15 per one run.

  Subsequently, in steps S <b> 21 to S <b> 24, the number of operating PTC heaters 15 is determined according to the necessity of heating the blown air into the vehicle interior by the PTC heater 15. For example, the number of operating PTC heaters 15 is determined according to the air mix opening degree and the coolant temperature.

  In step S21, it is determined whether or not the PTC heater operation is necessary (f (SW) = ONorOFF) based on the air mix opening SW. The smaller the air mix opening SW, the smaller the warm air ratio. Therefore, if the air mix opening SW is small, it is considered unnecessary to heat the blown air by the PTC heater 15. Therefore, in step S21, the air mix opening SW determined in step S5 is compared with a predetermined opening, and if the air mixing opening SW is smaller than the predetermined opening, in this example, 30%, The PTC heater is stopped (f (SW) = OFF). On the other hand, if the air mix opening is larger than the predetermined opening, in this example, 40%, the PTC heater is activated (f (SW) = ON).

  In step S22, it is determined whether the result of necessity of PTC heater operation determined in step S21 is PTC heater stop (f (SW) = OFF). At this time, if f (SW) = OFF (in the case of YES determination), the process proceeds to step S24, and the number of operating PTC heaters is determined to be zero. On the other hand, if f (SW) = ON (NO determination), the process proceeds to step S23.

  In step S23, the number of operating PTC heaters 15 is determined according to the cooling water temperature TW. Specifically, the first predetermined temperature T1> the second predetermined temperature T2> the third predetermined temperature T3 is determined in advance. When TW> T1, the number of operation is 0, and when T1> TW> T2, the operation is performed. The number is one. When T2> TW> T3, the number of operations is two. When T3> TW, the number of operations is three. In this example, T1, T2, and T3 used when increasing the number of operations (when the cooling water temperature is lowered) are 65 ° C., 62.5 ° C., and 60 ° C., respectively, and when decreasing the number of operations (cooling water temperature) T1, T2, and T3 used at the time of rising of 67.5 ° C., 65 ° C., and 62.5 ° C., respectively.

  As described above, after the number of operating PTC heaters 15 is determined in steps S21 to S24, it is determined in step S25 whether the determined number of operating PTC heaters 15 is zero. At this time, if the number of operation is 0, a YES determination is made, the process proceeds to step S26, the count is temporarily stopped, and the count is not added. On the other hand, if the number of operation is one or more, NO is determined, the process proceeds to step S27, the count is continued, the count is added and stored in the memory. This count is reset when the IG is turned from ON to OFF in order to measure the operation time per one run. In step S1, this count may be reset. Thus, since the operation time per one run is measured by steps S25, S26, and S27, steps S25, S26, and S27 serve as a timer 50a that measures the operation time per one run.

  Subsequently, in step S11 of FIG. 4, it is determined whether or not an engine EG operation request (engine ON request) is necessary. In this step S11, when the engine EG is stopped due to the remaining battery level and the traveling conditions, the operation and stop of the engine EG for air conditioning are determined.

  Here, in an ordinary vehicle that obtains driving force for vehicle travel only from the engine EG, the engine is always operated, so that the engine cooling water is also constantly at a high temperature. Therefore, in an ordinary vehicle, sufficient heating performance can be exhibited by circulating engine cooling water to the heater core 14.

  On the other hand, in the hybrid vehicle as in the present embodiment, if the remaining battery level is sufficient, the vehicle can travel by obtaining the driving force for traveling only from the traveling electric motor. For this reason, even when high heating performance is required, if the engine EG is stopped, the engine coolant temperature only rises to about 40 ° C., and the heater core 14 cannot exhibit sufficient heating performance.

  Therefore, in this embodiment, even when high heating performance is required, when the engine coolant temperature TW is lower than a predetermined reference coolant temperature, the engine coolant temperature TW is maintained at a predetermined temperature or higher. Then, an engine operation request signal (engine ON request signal) is output from the air conditioning control device 50 to the engine control device 70 used for controlling the engine EG so as to operate the engine EG. Thereby, the engine coolant temperature TW is raised to obtain high heating performance.

  However, such an output of the engine ON request signal causes the engine EG to operate even when it is not necessary to operate the engine EG as a driving source for vehicle travel. Become. For this reason, it is desirable to reduce the frequency of outputting the engine ON request signal as much as possible.

  Therefore, in the present embodiment, as will be described later, when the PTC heater 15 is stopped, the output frequency of the engine ON request signal is lower when the PTC heater 15 is operated than when the PTC heater 15 is stopped. An output condition different from the output condition of the engine ON request signal to be used is used.

  FIG. 6 is a flowchart showing details of step S11. The detailed contents of step S11 will be described with reference to FIG. In steps S30 to S32 shown in FIG. 6, a determination threshold value used for determining whether or not a temporary engine ON request is necessary based on the engine coolant temperature performed in step S33 is calculated.

  First, in step S30, based on the blower motor voltage determined in step S6 and the outlet mode determined in step S8, the total air volume (hereinafter referred to as the blower air volume) from the blower (blower) 12 is calculated. Specifically, as described in step S30 of FIG. 6, a map indicating the relationship between the blower motor voltage and the blower air volume created for each outlet mode is stored in advance in the ECU, and based on this map. Estimate the blower air volume.

  As described above, in the calculation of the blower air volume, the blower outlet mode is considered even if the blower air flow rate is the same, for example, the blower air volume is larger in the FACE mode than in the FOOT mode. This is because the blower air volume varies depending on the pressure loss of the wind flowing in the casing 11 depending on the outlet mode.

Subsequently, in step S31, the blowout temperature rise amount ΔTptc due to the operation of the PTC heater 15 is calculated. This blowout temperature rise amount ΔTptc can be calculated by the above-described equation F2-3. That is, the blowout temperature rise amount ΔTptc is the power consumption W (Kw) of the PTC heater 15, the air density ρ (kg / m ³ ), the air specific heat Cp, and the PTC passage air amount Va (m that is the amount of air passing through the PTC heater 15. ³ / h).
ΔTptc = W / ρ / Cp / Va × 3600 (F3)
Here, as the PTC passing air volume Va, a blower air volume is not simply used, but a value calculated by Formula F4, that is, an air mix opening SW (%) with respect to the blower air volume is used.
Va (m ³ / h) = Blower air volume (m ³ / h) × f (SW / 100) (F4)
Further, f (SW / 100) is calculated by SW / 100 when SW (%) is 10 or more and 100 or less, as shown in the relationship diagram between f (SW / 100) and SW described in step S31. Using the results, f (SW / 100) is set to 0.1 when SW (%) <10, and f (SW / 100) is set to 1 when SW (%)> 100.

For example, when the blower air flow rate = 250 m ³ / h, the power consumption W of the PTC heater W = 840 W, and the air mix opening SW = 100%, ΔTptc = 0.84 / 1.29 / 1/250 × 3600 = 9.3 It becomes ℃.

  In this way, the blowout temperature rise amount ΔTptc can be calculated so as not to deviate from the blowout temperature rise amount due to the actual operation of the PTC heater 15. ΔTptc is updated every 30 seconds with a time constant of 30 seconds.

  Subsequently, in step S32, an engine OFF water temperature and an engine ON water temperature which are determination threshold values used for determining whether or not a temporary engine ON request is necessary based on the engine coolant temperature performed in step S33 are calculated. The engine OFF water temperature is an engine cooling water temperature that is a determination criterion for stopping the engine, and the engine ON water temperature is an engine cooling water temperature that is a determination criterion for operating the engine.

Here, as the engine OFF water temperature, the smaller one of the reference cooling water temperature TWO and 70 ° C. calculated so that the actual blowing temperature becomes approximately the target blowing temperature TAO using Formula F5-1 is adopted. On the other hand, the engine ON water temperature is set lower than the engine OFF water temperature by a predetermined temperature, in this example, 5 ° C., in order to prevent frequent engine ON / OFF.
TWO = {(TAO−ΔTptc) − (TE × 0.2)} / 0.8 (F5-1)
The reference cooling water temperature TWO is a cooling water temperature that is required when it is assumed that the warm air temperature TWD before the air mixing becomes the target blowing temperature TAO. TE is the temperature of air blown from the evaporator 13 detected by the evaporator temperature sensor 56.

Here, the formula F5-1 is derived from the following formulas F5-2 and F5-3 for the blown air temperature Ta from the heater core 14. That is, Formula F5-1 is derived by substituting the right side of Formula F5-3 for the left side of Formula F5-2 and solving for TWO.
Ta = TWO × α + TE × β (F5-2)
Ta = TAO−ΔTptc (F5-3)
In Formula F5-2, α is the heat exchange efficiency of the heater core 14, and β is the contribution of the blown air temperature TE from the evaporator 13 to the blown air temperature Ta from the heater core 14. In this example, α is 0.8 and β is 0.2.

  Subsequently, in step S33, it is determined whether a temporary engine ON request is necessary based on the engine coolant temperature. This determination result f (TW) is a parameter for determining whether or not an engine ON request is required in the next step S34.

  Specifically, the actual cooling water temperature detected by the cooling water temperature sensor 58 is compared with the engine OFF water temperature and the engine ON water temperature obtained in step S32. If the coolant temperature is lower than the engine ON water temperature, the engine operation is temporarily determined as f (TW) = ON, and if the coolant temperature is higher than the engine OFF water temperature, the engine stop is temporarily determined as f (TW) = OFF. To do.

  Subsequently, in step S34, whether or not an engine operation (ON) request for air conditioning is necessary is determined based on the outlet mode, the number of operating PTC heaters 15, the target outlet temperature TAO, and the determination result f (TW) in step S33. I do.

  Specifically, if the air outlet mode is other than the FACE mode, whether or not an engine ON request is required is determined according to f (TW).

  Usually, since the outlet mode at the time of heating is FOOT mode or B / L mode, it corresponds to those other than FACE mode at the time of heating. In this case, if the cooling water temperature is lower than the engine ON water temperature calculated in step S32, cold air comes out from the feet and impairs comfort, so the engine ON is selected. As a result, an engine ON request signal is output and the temperature of the engine cooling water rises. Therefore, during heating, when air passes through the heater core 14, the air is heated using the engine cooling water as a heat source, and after passing through the heater core By adding the air temperature increase amount by the PTC heater 15 to the air temperature, it becomes possible to create an air temperature that is approximately equal to the target air temperature TAO, and passenger comfort is maintained.

  Further, when the cooling water temperature is higher than the engine OFF water temperature calculated in step S32 in the FOOT mode or the B / L mode, the engine OFF is selected. In this case, for example, if an engine stop signal is output and the engine for air conditioning is operating, the engine is stopped.

  Here, in step S32, the calculation is performed so that the engine OFF water temperature and the engine ON water temperature become smaller as the blowing temperature rise amount ΔTptc by the PTC heater 15 becomes larger. Therefore, when the PTC heater is in operation, the PTC heater 15 is stopped. As a result, the frequency of engine ON requests is reduced, and fuel efficiency is improved. Further, since the PTC passage air volume is added to the blowout temperature rise amount ΔTptc, when the PTC passage air volume is low, the engine OFF water temperature and the engine ON water temperature can be greatly reduced, and the fuel saving effect can be increased.

  On the other hand, when the outlet mode is the FACE mode, the necessity of an engine ON request for air conditioning is determined according to the number of PTC heaters 15 operated, the target outlet temperature TAO, and f (TW) as follows. To do.

  When the number of operating PTC heaters is a predetermined number, in this example, one or more, the engine stop (OFF) is selected regardless of the coolant temperature TW and the target outlet temperature TAO, and the engine ON request signal is not output.

  Thereby, since an engine ON request signal is not output in step S13 described later, the engine remains stopped even if the cooling water temperature is lower than the engine ON water temperature. Alternatively, if the engine for air conditioning is operating, an engine stop signal is output and the engine is stopped. As a result, in the FACE mode, when the number of operating PTC heaters is 1 or more, as long as there is a remaining battery level, traveling by an electric motor (EV traveling) is possible, and zero emission (exhaust gas emission amount) Can be 0).

  Here, in the air outlet mode other than the FACE mode, the engine operation is selected when the coolant temperature is lower than the engine OFF water temperature, whereas in the FACE mode, regardless of the coolant temperature, The engine stop is selected because, in the FACE mode, even if the coolant temperature is lower than the temperature required to obtain the target outlet temperature TAO, the influence on passenger comfort is small. In other words, the FACE mode is an air outlet mode in which air conditioned air having a lower temperature than the FOOT mode and the B / L mode is blown out from the face air outlet, and the air at a temperature lower than the target air temperature TAO in the FACE mode. This is because there is little possibility that the occupant feels uncomfortable even if the air is blown out from the face outlet toward the upper body of the occupant.

  However, if the difference between the actual blowout air temperature from the face blowout port and the target blowout temperature TAO is too large, the room temperature will drop too much. As a result, the target blowout temperature TAO will change and the blowout port mode will change from the FACE mode. It will be changed to B / L mode. Therefore, in this embodiment, even if the engine is stopped and the cooling water temperature is low, the engine ON request signal is not output when the PTC heater 15 is operated in the FACE mode so that the room temperature does not decrease too much. I am going to do that.

  In addition, when the number of operating PTC heaters 15 is 0, that is, when the PTC heater 15 is stopped, the target blowing temperature TAO is equal to the predetermined blowing temperature TAO, which is less than 20 ° C. in this example. When the temperature is relatively low, heating of the air by the heater core 14 is not necessary, so the engine stop (OFF) is selected and the engine ON request signal is not output. In this case, if the engine for air conditioning is operating, an engine stop signal is output and the engine EG is stopped.

  When the number of PTC heaters 15 is 0 and the target blowing temperature TAO is a predetermined temperature, which is 20 ° C. or higher in this example, the engine for air conditioning is turned on as in the case other than the FACE mode. The necessity of the request is determined according to f (TW). Thus, if the coolant temperature is lower than the engine ON water temperature, an engine ON request signal is output, and the engine coolant is heated by the engine operation. This is because when the number of PTC heaters 15 is 0 and the target blowout temperature TAO is equal to or higher than the predetermined temperature, if the cooling water temperature is low, the room temperature gradually decreases with the passage of time. It is to do.

  In step 12 of FIG. 4, it is determined whether or not the electric water pump 42 that circulates engine coolant between the heater core 14 and the engine EG is required. FIG. 7 is a flowchart showing details of step S12. The detailed contents of step S12 will be described with reference to FIG. This step S12 is executed regardless of the ON / OFF state of the engine EG and the air outlet mode.

  As shown in FIG. 7, in step S <b> 40, it is determined whether or not the coolant temperature TW detected by the coolant temperature sensor 58 is higher than the blown air temperature TE from the evaporator 13 detected by the evaporator temperature sensor 56. . At this time, when the cooling water temperature TW is lower than the blown air temperature TE from the evaporator 13 (in the case of NO determination), the process proceeds to step S43 and the stop (OFF) of the electric water pump 42 is selected. As a result, the electric water pump 42 is stopped, and the circulation of the cooling water in the cooling water circuit 40 is stopped. This is because, when the cooling water temperature TW is lower than the blown air temperature TE from the evaporator 13 and the cooling water is flowed to the heater core 14, the air after passing the evaporator is cooled by the cooling water flowing through the heater core 14, This is because the temperature of the air blown from the outlet is lowered.

  On the other hand, when the cooling water temperature TW is higher than the blown air temperature TE from the evaporator 13 (in the case of YES determination), the process proceeds to step S41.

  In step S41, it is determined whether the blower operation (blower ON) is selected.

  At this time, if the blower stop is selected, the determination is NO, and in order to save power, the process proceeds to step S43, and the stop (OFF) of the electric water pump 42 is selected. As a result, when the blower is stopped, the electric water pump 42 is also stopped.

  On the other hand, if the blower operation is selected, the determination is YES, the process proceeds to step S42, and the operation (ON) of the electric water pump 42 is selected. As a result, the electric water pump 42 operates and the cooling water circulates in the refrigerant circuit, whereby the blown air is heated by heat exchange between the cooling water flowing through the heater core 14 and the air passing through the heater core 14.

  In step S13 in FIG. 4, various devices 12, 61, 35, 62, 63, 64, 15a, 15b, 15c, and the like are obtained from the air conditioning control device 50 so that the control state determined in steps S5 to S12 described above is obtained. A control signal and a control voltage are output to 42 and the engine control device 70.

  Thereby, for example, the PTC heater 15 operates with the number of operations determined in step 10, and the electric water pump 42 operates or stops as determined in step S12.

  In addition, if an engine ON request signal for air conditioning is output to the engine control device 70, if the remaining battery level is equal to or greater than a predetermined amount and the engine EG is stopped due to traveling conditions, the engine EG Operate. Further, when the engine EG is operating for air conditioning, the engine EG stops when an engine stop signal (engine OFF signal) is output, for example, depending on conditions such as the engine coolant temperature.

  In the next step S14, the process waits for the control period τ, and returns to step S2 when it is determined that the control period τ has elapsed. In the present embodiment, the control cycle τ is 250 ms. This is because the air conditioning control in the passenger compartment does not adversely affect the controllability even if the control period is slower than the engine control or the like. Furthermore, it is possible to suppress a communication amount for air conditioning control in the vehicle and to sufficiently secure a communication amount of a control system that needs to perform high-speed control such as engine control.

  Next, main feature points of the present embodiment will be described.

  (1) The air conditioning control device 50 of the present embodiment is the step S34 in FIG. 6, and in the FACE mode, when the PTC heater 15 is stopped, the target outlet temperature TAO is equal to or higher than the predetermined temperature, and the cooling water temperature TW. Is determined to output an engine ON request signal when the engine temperature is lower than the engine ON water temperature. On the other hand, when the PTC heater 15 is in operation in the FACE mode, it is determined not to output the engine ON request signal regardless of the coolant temperature TW. For this reason, since the frequency of the engine ON request is lower when the PTC heater 15 is activated than when the PTC heater 15 is stopped, according to the present embodiment, the output condition of the engine ON request signal used when the PTC heater 15 is activated. As compared with the case where the PTC heater 15 is stopped, the fuel consumption can be improved.

  (2) The air conditioning control device 50 measures the total Tsum of the operating time of the PTC heater 15 per one run from the time when the IG is turned off to the time when the IG is turned off again in steps S25 to S27 in FIG. Yes. Then, in step S20 of FIG. 5, it is determined whether or not the total time Tsum of the operating time of the PTC heater 15 has exceeded a predetermined time limit, 43 minutes in this example, and if the predetermined time limit has elapsed, In S24, the stop of the PTC heater 15 is determined. Further, for the predetermined time limit, the total operation time of the PTC heater does not exceed the operation limit time of the PTC heater 15 so that the failure of the PTC heater 15 does not occur within the durable period of the vehicle. The calculated value is used.

  In this way, in this embodiment, the operating time of the PTC heater 15 per one run is limited, and the total operating time of the PTC heater in the durable life period of the vehicle is suppressed so as not to exceed the operating limit time. Therefore, the risk of failure of the PTC heater 15 within the durable years of the vehicle can be reduced.

  (3) In the present embodiment, in order to prevent the failure of the PTC heater 15 from occurring within the durable years of the vehicle, the operation time of the PTC heater 15 per run is limited to 43 minutes, The use restriction of the PTC heater due to the temperature can be made unnecessary.

  Here, as explained in the column of the problem to be solved by the above-described invention, the use restriction of the PTC heater according to the outside air temperature is provided, the reference temperature at that time is set to a low temperature such as 10 ° C., and the target blowing If the use of the PTC heater 15 is limited only to the cold time when the outside air temperature is 10 ° C. or less so that the FOOT mode is selected as the outlet mode determined based on the temperature TAO, the outside air temperature is 10 ° C. in one year. The PTC heater 15 cannot be used in an area where the cold time to be below is low and the FACE mode is selected at a relatively high frequency in one year, and thus there arises a problem that the effect (1) described above cannot be obtained.

  On the other hand, in the present embodiment, there is no restriction on the use of the PTC heater depending on the outside air temperature. Therefore, the use of the PTC heater 15 is not limited to the cold time when the FOOT mode is selected, and the bi-level mode or FACE is used. Even when the mode is selected, the PTC heater 15 can be used.

  Therefore, according to the present embodiment, the PTC heater 15 can be operated even in an area where the frequency of selecting the FACE mode in the year is relatively high, and the operation time of the PTC heater 15 can be sufficiently secured. The effect of (1) is obtained.

  (4) When the cooling water temperature TW is higher than the first predetermined temperature T1 as the predetermined temperature in step S23 of FIG. 5, the air conditioning control device 50 determines the number of operation of the PTC heater 15 to be 0 and continues. In steps S25 and S26, the count is temporarily stopped. On the other hand, when the cooling water temperature TW is lower than the first predetermined temperature T1 in step S23 of FIG. 5, the number of operating PTC heaters 15 is determined to be 1 or more, and the count is continued in steps S25 and S27. Like to do.

  For this reason, when the engine EG is activated for a purpose other than air conditioning such as battery charging or high-speed running during the operation of the PTC heater 15 and the cooling water temperature TW becomes higher than T1, the PTC heater 15 is stopped. Therefore, the air conditioning control device 50 stops the PTC heater 15 in operation and temporarily stops counting. Then, when the cooling water temperature TW falls from a temperature higher than T1 to a temperature lower than T1, the operation of the PTC heater 15 is started again and the count is restarted. As a result, it is possible to increase the time from when the IG is turned on until the operating time of the PTC heater 15 per run elapses the predetermined time limit, and the time for obtaining the effect (1) described above can be obtained. Can be long.

  (5) In the air conditioning control device 50, when the air mix opening degree SW is smaller than the predetermined opening degree in steps S21, S22, and S24 in FIG. 5, that is, the warm air ratio adjusted by the air mixing door 19 is a predetermined ratio. If the number of the PTC heaters 15 is smaller, the number of PTC heaters 15 to be operated is determined to be 0, and the count is temporarily stopped in subsequent steps S25 and S26. On the other hand, when the air mix opening degree SW is larger than the predetermined opening degree, that is, when the warm air ratio adjusted by the air mix door 19 is larger than the predetermined ratio, in steps S21, S22, and S23 of FIG. If the temperature TW is higher than the predetermined temperature, the number of operation of the PTC heater 15 is determined to be 1 or more, and the counting is continued in the subsequent steps S25 and S27.

  For this reason, while the PTC heater 15 is in operation, the engine EG is operated for purposes other than air conditioning such as battery charging and high-speed running, the cooling water temperature TW becomes high, and it is necessary even if the warm air is not mixed much by air mix control. In the case where a proper blowout temperature is obtained, a sufficient feeling of heating can be obtained even if the PTC heater 15 is stopped. Therefore, the air conditioning control device 50 stops the PTC heater 15 in operation and temporarily stops counting. It will be. When the air mix opening SW is increased from an opening smaller than the predetermined opening to an opening larger than the predetermined opening, that is, the ratio of the warm air ratio is smaller than the predetermined ratio to larger than the predetermined ratio. When it increases, the operation of the PTC heater 15 is started again and the count is restarted. As a result, it is possible to increase the time from when the IG is turned on until the operating time of the PTC heater 15 per run elapses the predetermined time limit, and the time for obtaining the effect (1) described above can be obtained. Can be long.

(Second Embodiment)
In the first embodiment, the control process for determining the necessity of the engine EG operation request (engine ON request) in step S11 of FIG. 4 is executed in the control flow of steps S30 to S34 shown in FIG. In the control flow shown in FIG. 6, step S34 may be omitted, and step S33 may be changed to the final determination instead of the provisional determination.

  That is, in the first embodiment, when determining the necessity of an engine operation request for air conditioning, the outlet mode, the number of PTC heaters 15 to operate, and the target outlet temperature TAO are used as parameters for determining necessity. In the present embodiment, only the engine coolant temperature is used as a parameter for determining necessity, and in step S33 in FIG. 6, the necessity determination of the engine ON request based on the engine coolant temperature is performed. Others are the same as in the first embodiment.

  Even if it does in this way, the effect of (1)-(5) demonstrated in 1st Embodiment is acquired.

  Regarding the effect (1) described above, in this embodiment, when the cooling water temperature TW is lower than the engine ON water temperature, it is determined to output the engine ON request signal, and the engine ON water temperature used at this time is determined. In step S32 of FIG. 6, when the PTC heater 15 is operated, the engine ON water temperature is calculated to be lower than when the PTC heater 15 is stopped in consideration of the blowout temperature rise amount ΔTptc. For this reason, when the PTC heater 15 is operated, the frequency of the engine ON request becomes lower than when the PTC heater 15 is stopped. Therefore, according to the present embodiment, the engine ON water temperature when the PTC heater 15 is operated is set as the PTC heater 15. Compared with the case where it is the same as the time of 15 stop, a fuel consumption can be improved.

  Regarding the effect of the above (3), similarly to the first embodiment, there is no restriction on the use of the PTC heater due to the outside air temperature, in which the use of the PTC heater 15 is only 10 ° C. or less, for example. The use of the PTC heater 15 is not limited to a cold time of, for example, 10 ° C. or less, and the PTC heater 15 can be used even in an area where the cold time of 10 ° C. or less is small. For this reason, according to the present embodiment, the operation time of the PTC heater 15 can be sufficiently secured even in an area where the cold period is small, and the effect of improving the fuel consumption by reducing the engine ON water temperature when the PTC heater 15 is operated is obtained. It is done.

(Third embodiment)
In the first and second embodiments, the air conditioning control device 50 is configured to stop the PTC heater 15 when the operation time of the PTC heater 15 per run has exceeded a predetermined time such as 43 minutes. Instead of this, the PTC heater 15 may be stopped when the capacity of the traveling battery of the hybrid vehicle becomes smaller than a predetermined capacity.

  In the first and second embodiments, the time limit for operating the PTC heater 15 per travel is set in consideration of the fact that the total operation time of the PTC heater does not exceed the operation limit time of the PTC heater 15. However, the time limit may be set in consideration of the battery capacity. In consideration of the amount of power consumed by the operation of the PTC heater 15 and the battery capacity, the time limit may be set to 30 minutes, for example.

(Other embodiments)
(1) In each of the above-described embodiments, the PTC heater 15 is used as the electric heater, but another electric heater using a nichrome wire or the like may be used.

  Further, in each of the above-described embodiments, the electric heater that is disposed in the air conditioning case and directly heats the air blown into the vehicle interior is used as the electric heater. Instead, the electric heater is provided in the engine cooling water circuit. A water heating type electric heater for heating the engine cooling water may be used. In this case, the water heating type electric heater indirectly heats the air blown into the vehicle compartment via the engine cooling water.

  As the electric heater, other electric heaters may be used as long as they can heat the passenger compartment so that passengers can be heated. For example, an electric heater for seat air conditioning that is disposed in a seat (seat) of a vehicle and heats the air blown from the seat or the seat into the vehicle interior, or an electric heater for steering that heats the steering may be used. .

  (2) In each of the above-described embodiments, the vehicle air conditioner of the present invention is a so-called parallel type hybrid vehicle that can travel by directly obtaining driving force from both the engine EG and the traveling electric motor in the hybrid vehicle. Although the applied example is described, the application of the vehicle air conditioner of the present invention is not limited to this. For example, the engine EG is used as a drive source for the generator, the generated power is stored in a battery, and further, the drive power is obtained from a traveling electric motor that operates by being supplied with the power stored in the battery. The present invention may be applied to a so-called serial type hybrid vehicle.

  (3) In each of the above-described embodiments, the vehicle air conditioner of the present invention is applied to a vehicle air conditioner mounted on a hybrid vehicle. However, the present invention is not limited to a hybrid vehicle, and the engine is automatically stopped when stopped. The present invention can also be applied to a vehicle air conditioner mounted on an idling stop vehicle, a fuel cell vehicle, an electric vehicle or the like.

  The vehicle air conditioner mounted on the fuel cell vehicle changes the engine EG in FIG. 1 to a fuel cell with respect to the vehicle air conditioner described above, and the heater core heats the blown air using the cooling water of the fuel cell as a heat source. It has been changed to. In this case, the fuel cell corresponds to the temperature raising means of the heat medium in the present invention, and the cooling water of the fuel cell corresponds to the heat medium of the present invention.

  Further, the vehicle air conditioner mounted on the electric vehicle changes the engine EG in FIG. 1 to a water heating type electric heater with respect to the vehicle air conditioner described above, and the heater core is heated by the water heating type electric heater. The hot air is used as a heat source so that the blown air is heated. In this case, the water heating type electric heater corresponds to the temperature raising means of the heat medium in the present invention, and the hot water heated by the water heating type electric heater corresponds to the heat medium of the present invention.

  Also in these vehicle air conditioners, when the electric heater is operated, the operation request for the temperature raising means used when the electric heater is stopped so that the frequency of the temperature raising means is lower than when the electric heater is stopped. By using an output condition that is different from the signal output condition, the energy consumed when the temperature raising means is activated is saved when the electric heater is activated and when the electric heater is deactivated, as compared with those using the same output condition. Can save energy.

  In this case, by restricting the operating time of the electric heater per run to a predetermined time, it is not necessary to restrict the use of the electric heater due to the outside air temperature when the electric heater is used only at a time of, for example, 10 ° C. or less. Therefore, the effect (1) described in the first embodiment can be obtained.

  In fuel cell vehicles and electric vehicles, starting and stopping of a vehicle control system that controls an electric motor as a travel drive source corresponds to ON and OFF of IG in a vehicle having only an engine or a hybrid vehicle.

  (4) In the first and second embodiments, when the operation number of the PTC heater 15 is determined in step S10, as shown in steps S21 to S24 of FIG. 5, according to the necessity of heating of the PTC heater 15. In order to determine the operation of the PTC heater 15, the number of the PTC heaters 15 is determined based on the air mix opening SW and the cooling water temperature TW regardless of the outside air temperature. If the purpose is to determine the operation of the PTC heater 15 according to the necessity of heating, the number of the PTC heaters 15 may be determined based on the outside air temperature.

  That is, before executing step S21 of FIG. 5, it is determined whether or not the outside air temperature is higher than a reference temperature such as 26 to 30 ° C., and if higher than the reference temperature, the stop of the PTC heater 15 is determined. Also good. The reference temperature used at this time may be set to a temperature at which the heating of the PTC heater 15 for assisting the heating by the heater core 14 becomes unnecessary as in summer. Thus, the electric heater may be stopped when the outside air temperature is high enough that there is no need for heating by the electric heater.

14 Heater core (heat exchanger for heating)
15 PTC heater (electric heater)
50 Air-conditioning control device (control means)
EG engine

Claims (6)

A heat exchanger (14) for heating that heats the air blown into the passenger compartment by heat exchange between the heat medium whose temperature has been raised by the temperature raising means (EG) and air;
When a predetermined output condition is satisfied, a control means (50) for outputting an operation request signal to the temperature raising means (EG) in order to maintain the temperature of the heat medium at a predetermined temperature or higher,
An electric heater (15) that is activated or stopped by the control means (50) and that heats the interior of the passenger compartment as the air is heated by the heating heat exchanger.
The control means (50) is set as an output condition of the operation request signal so that the operating frequency of the temperature raising means (EG) when the electric heater is operating is lower than when the electric heater is stopped. In the vehicle air conditioner adapted to use the output condition,
A measuring means (50a) for measuring an operation time of the electric heater per one run from the start to the stop of the vehicle control system for controlling the vehicle drive source;
The control means (50) determines the operation of the electric heater (15) according to the necessity of heating by the electric heater (15), and the operation time measured by the measuring means (50a) is predetermined. The vehicular air conditioner is characterized in that when the time has elapsed, the electric heater (15) is determined to stop.   The vehicle air conditioner according to claim 1, wherein the control means (50) determines the operation of the electric heater (15) when the temperature of the heat medium is lower than a predetermined temperature. The control means (50) determines the stop of the electric heater (15) when the electric heater (15) is in operation and the temperature of the heat medium is higher than the predetermined temperature. Temporarily stop the measurement by the measuring means (50a),
When the temperature of the heat medium falls from a temperature higher than the predetermined temperature to a temperature lower than the predetermined temperature, the operation of the electric heater (15) is determined and the measurement by the measuring means (50a) is resumed. The vehicular air conditioner according to claim 2, wherein the vehicular air conditioner is configured to be used. The heating heat exchanger (14) is disposed, and a warm air passage (16) through which warm air blown from the heating heat exchanger (14) flows;
A cold air passage (17) through which the cold air flows, bypassing the heating heat exchanger (14);
A mixing space (18) in which the warm air from the warm air passage (16) and the cold air from the cold air passage (17) are mixed;
Temperature adjusting means (19) for adjusting the air volume ratio of the cool air and the warm air flowing into the mixing space (18) to adjust the temperature of the blown air into the passenger compartment,
The electric heater (15) is disposed on the downstream side of the air flow of the heating heat exchanger (14) in the warm air passage,
The control means (50) operates the electric heater (15) when the electric heater (15) is in operation and the warm air ratio adjusted by the temperature adjusting means (19) is smaller than a predetermined ratio. ) And stop the measurement by the measuring means (50a),
When the warm air ratio increases from a ratio smaller than the predetermined ratio to a ratio larger than the predetermined ratio, the operation of the electric heater (15) is determined and the measurement by the measuring means (50a) is restarted. The vehicle air conditioner according to any one of claims 1 to 3, wherein the vehicle air conditioner is configured as described above.   The control means (50) outputs the operation request signal when the temperature of the heat medium is lower than a threshold as an output condition of the operation request signal, and when the electric heater (15) is operated. 5. The vehicular air conditioning according to claim 1, wherein the output condition is set to be lower than the threshold value when the electric heater is stopped. apparatus. The heating heat exchanger (14) uses engine (EG) cooling water as the heat medium,
6. The vehicle air conditioner according to claim 1, wherein the temperature raising means is the engine (EG).

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