JP3552392B2 - Vehicle air conditioner - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a vehicle air conditioner that heats a vehicle interior using hot water heated by a combustion heater as a heat source, and is particularly suitable for use in an electric vehicle.
[0002]
[Prior art]
As a first prior art of an air conditioner for a vehicle, hot water heated by a combustion heater is configured to flow through a heater core in an air conditioning case, and the heating water heating capacity of the combustion heater is adjusted during a heating operation. In some cases, the temperature of the water in the heater core is adjusted to adjust the temperature of the air blown into the vehicle interior.
[0003]
As a second prior art of a vehicle air conditioner, a control device for an air conditioner calculates a target blow-off temperature of air blown into a vehicle cabin, and based on the target blow-off temperature, temperature control means (for example, an air mix door). ) Is controlled so that the temperature of the air blown out into the vehicle compartment becomes the target air outlet temperature.
[0004]
[Problems to be solved by the invention]
The present inventors calculate the target water temperature based on a combination of the first and second prior arts, that is, the target outlet temperature, and control the combustion heater so that the water temperature becomes the target water temperature. The following considerations were made on the results.
For example, in winter, when the vehicle interior temperature has dropped to near the outside air temperature, at the start of heating, the target outlet temperature is calculated as a high temperature, and based on this, the target water temperature is also calculated as a high temperature. The hot water heating capacity of the combustion heater is also controlled with a high capacity based on the target water temperature. Then, as the vehicle interior warms, the target outlet temperature gradually decreases, and the target water temperature also decreases accordingly.
[0005]
However, it is difficult for a normal combustion type heater to operate at a predetermined minimum capacity (for example, 3000 kcal / h) or less from the viewpoint of securing stability of combustion state and durability. Therefore, even when (target water temperature) <(water temperature at the time of the minimum capacity), since the combustion type heater is operated at the minimum capacity, the actual water temperature does not become the target water temperature but becomes the water temperature at the time of the minimum capacity. As a result, as described above, while the target water temperature gradually decreases as the vehicle interior temperature increases, the actual water temperature becomes constant at the water temperature at the minimum capacity and does not further decrease. And the actual water temperature will be different.
[0006]
The present inventors have discovered that the following problem occurs when a situation occurs in which the target water temperature decreases but the actual water temperature does not decrease.
(First problem)
For example, at the time of the heating operation, the target blower voltage is calculated so that the blower voltage decreases when the target blowout temperature decreases, the target blower voltage is applied to the blower motor, and further determined by the target blower voltage. When the target water temperature in the heater core is calculated such that (the temperature of the air blown into the vehicle compartment) = (the target air temperature) when the amount of the blown air is large, the following first problem occurs. appear.
[0007]
When (air temperature of the air blown into the vehicle compartment) = (target air temperature), that is, when (water temperature) = (target water temperature), the heat given to the hot water by the combustion type heater is calculated based on the target air temperature. As a result of the wind at the determined air volume being taken by the heater core, (air temperature of the air blown into the vehicle compartment) = (target air temperature) and (water temperature) = (target water temperature). No problem.
[0008]
However, as described above, when (target water temperature) <(water temperature at minimum capacity) and there is a difference between the target water temperature and the actual water temperature, the combustion type heater is operated at the minimum capacity. The same amount of heat as when (target water temperature) = (water temperature at minimum capacity) is given to the hot water. That is, at this time, extra heat is given to the hot water.
[0009]
Here, as described above, during the heating operation, the blower voltage also decreases as the target blow-out temperature decreases, so that the blower voltage when (target water temperature) <(water temperature at minimum capacity) is (target water temperature) = (Lowest capacity water temperature) is lower than the blower voltage. Therefore, the excess heat given to the hot water when (target water temperature) <(water temperature at the time of minimum capacity) cannot be completely dissipated by the heater core, and as a result, the water temperature gradually rises.
[0010]
Then, the water temperature may reach a temperature (for example, 110 ° C.) set for overheating protection of the combustion heater, and in this case, the combustion heater stops. As a result, the temperature of the air blown out into the vehicle interior drops sharply, giving the occupant a sense of discomfort.
(Second problem)
In the case where the outlet mode is controlled so as to be in the foot mode, the bi-level mode, and the face mode as the target outlet temperature changes from the higher to the lower, the second Problems arise.
[0011]
That is, the fact that the actual water temperature does not decrease even though the target water temperature has decreased means that the actual blown air temperature has not decreased even though the target blowout temperature has decreased. In other words, it means that wind having a temperature higher than the target blowing temperature is blown into the vehicle interior. Naturally, at this time, the target outlet temperature further decreases.
As a result, the warm air that has been blown to the feet of the occupant in the foot mode until then is changed to the bi-level mode or the face mode, and the warm air is blown to the occupant's face. Then, the occupant is discomforted.
[0012]
In view of the above, the present invention occurs when the target heating capacity (the target water temperature mentioned above) of the combustion device (the above-mentioned combustion type heater) falls below the minimum capacity (the water temperature at the time of the minimum capacity mentioned above). The purpose is to prevent problems.
[0013]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claims 1 and 2
Under the condition that the target heating capacity of the combustion device (33) is lower than the minimum capacity, the blower means sets the amount of air blown into the vehicle cabin to a predetermined airflow larger than the airflow calculated by the target airflow calculator (S160). (6) is controlled.
[0014]
Here, the "predetermined air volume" refers to the air volume calculated by the target blow air volume calculation means (S160) when the heating capacity of the combustion device (33) is the minimum capacity, or higher.
According to this, when the condition that the target heating capacity is lower than the minimum capacity, that is, for example, as described above (target water temperature) <(water temperature at the time of minimum capacity), the amount of air blown into the vehicle cabin becomes the above-described predetermined air volume. . Therefore, excess heat given to the heat medium by the combustion device is radiated by the heat exchanger for heating, so that a rise in the temperature of the heat medium is suppressed, and the problem that the combustion device is stopped can be prevented.
[0015]
The invention according to claims 3 and 4 is:
Under the above conditions, the air outlet opening / closing means (18, 19) is controlled so as to be in a foot mode in which the face air outlet (15) is closed and the foot air outlet (16) is closed.
According to this, since the foot mode is set in the above condition, it is possible to prevent a problem that the warm air is blown out to the occupant's face and the occupant is uncomfortable.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, an embodiment in which the present invention is applied to an air conditioner for an electric vehicle will be described with reference to FIGS. First, the overall configuration of the present embodiment will be described with reference to FIG.
The indoor unit 1 includes an air conditioning case 2 as an air passage for guiding air into a vehicle interior. The air upstream side of the air conditioning case 2 is provided with an inside air suction port 3, an outside air suction port 4, and an inside / outside air switching door 5 for opening and closing each of the suction ports 3, 4. It is driven by a servo motor 48 (see FIG. 4).
[0017]
Downstream of the inside / outside air switching door 5, there is provided a fan 6 as a blowing means for generating an air flow in the air conditioning case 2. The fan 6 is driven by a blower motor 7.
In the air conditioning case 2, an indoor heat exchanger 9 forming a part of the refrigeration cycle 8 is provided. In the indoor heat exchanger 9, no refrigerant flows inside during a heating operation described later, and functions as an evaporator during a cooling operation described later.
[0018]
In the air-conditioning case 2, a heater core 11 as a heating heat exchanger forming a part of a hot water circuit 10 as a circulation circuit is provided downstream of the indoor heat exchanger 9. The heater core 11 is a heat exchanger that functions as a heater that heats the air in the air conditioning case 2. The ratio between the amount of air passing through the heater core 11 and the amount of air passing through the bypass passage 12 is determined by the opening of the air mix door 13, and the air mix door 13 is driven by a servo motor 49 (see FIG. 4). You.
[0019]
At the downstream end of the air conditioning case 2, a defroster outlet 14 for blowing the conditioned air to the inner surface of the windshield, a face outlet 15 for blowing the conditioned air toward the upper body of the vehicle occupant, and a conditioned air for the vehicle occupant. A foot outlet 16 that blows out toward the foot is formed. These air outlets 14 to 16 are opened and closed by doors 17 to 19 as air outlet opening and closing means, respectively, and these doors 17 to 19 are driven by a servomotor 50 (see FIG. 4) as a driving means thereof. You.
[0020]
The refrigeration cycle 8 includes, in addition to the indoor heat exchanger 9, a compressor 20, a refrigerant / water heat exchanger 21, an outdoor heat exchanger 22, a heating expansion valve 23, a cooling expansion valve 24, an accumulator 25, and a refrigerant. The electromagnetic valves 26 and 27 for switching the flow direction of the refrigerant are connected by refrigerant pipes 28, respectively. In the figure, reference numeral 29 denotes an outdoor fan.
[0021]
The compressor 20 sucks, compresses, and discharges refrigerant when driven by an electric motor (not shown). This electric motor is disposed integrally with the compressor 20 in a sealed case, and the rotation speed continuously changes by being controlled by the inverter 30 (see FIG. 4). The current supply to the inverter 30 is controlled by a control device 31 (see FIG. 4).
[0022]
The refrigerant / water heat exchanger 21 is specifically made of an aluminum alloy. As shown in FIG. 2, which is a cross-sectional view taken along the line AA of FIG. The refrigerant pipe 28 is connected to the formed passage 21b, and a hot water pipe 34 (described later) of the hot water circuit 10 is connected to the internal passage 21c of the pipe 21a. Then, the high-temperature and high-pressure refrigerant discharged from the compressor 20 flows through the passage 21b, and the hot water in the hot water circuit 10 flows through the internal passage 21c, whereby the refrigerant and the hot water exchange heat, and the refrigerant condenses, Hot water is warmed.
[0023]
The outdoor heat exchanger 22 functions as an evaporator during a heating operation described later, and functions as a condenser during a cooling operation described later. Further, the heating expansion valve 23 functions as a pressure reducing unit during a heating operation described later, and the cooling expansion valve 24 functions as a pressure reducing unit during a cooling operation described later. The solenoid valves 26 and 27 are energized and controlled by a control device 31 (see FIG. 4).
[0024]
The hot water circuit 10 includes, in addition to the heater core 11, a water pump 32 that generates a hot water flow in the hot water circuit 10, a combustion heater 33 that is provided outside the vehicle compartment and heats hot water, and the refrigerant / water heat exchanger 21. Are connected by a hot water pipe 34, respectively.
Specifically, as shown in FIG. 3, the combustion type heater 33 forms a box-shaped heater case 33a, a combustion cylinder 33b provided in the heater case 33a, and a fuel passage from the fuel tank to the combustion cylinder 33b. A fuel pipe 33c, a fuel pump 33d for pressure-feeding fuel to the combustion cylinder 33b via the fuel pipe 33c, a glow plug 33e for igniting the fuel at startup, a combustion fan 33f for blowing combustion air, and a rotational drive for the combustion fan 33f. It is composed of an electric motor 33g and the like.
[0025]
The combustion type heater 33 burns fuel such as gasoline, kerosene, light oil or the like inside the combustion tube 33b, and gives the calorific value to hot water.
Below the heater case 33a in FIG. 3, there are provided a suction pipe 33h for sucking combustion air and an exhaust pipe 33i for discharging combustion exhaust. A hot water passage 33j through which hot water flows is formed between the heater case 33a and the combustion tube 33b.
[0026]
Further, a warm water inflow port 33k is formed in the heater case 33a, and warm water from the warm water inflow pipe 331 flows into the warm water passage 33j from the warm water inflow port 33k. A hot water outflow port 33m is formed in the heater case 33a, and the hot water in the hot water passage 33j flows out of the hot water outflow port 33m through a hot water outflow pipe 33n.
[0027]
The combustion type heater 33 controls the applied voltage to the fuel pump 33d and the electric motor 33g to adjust the fuel supply amount and the air amount supplied into the combustion cylinder 33b, and the combustion amount (that is, the hot water heating capacity) Can be continuously adjusted from the minimum capacity (3000 kcal / h in this embodiment) to the maximum capacity (6000 kcal / h in this embodiment).
[0028]
As described above, the present embodiment has a configuration in which a known radiator is not provided in the hot water circuit 10.
Next, a control system according to the present embodiment will be described with reference to FIG.
The control device 31 includes a well-known microcomputer including a CPU, a ROM, a RAM, and the like (not shown), a drive circuit that controls a blower voltage applied to the blower motor 7, an A / D conversion circuit, and the like. The ignition switch 35 is turned on. Sometimes, power is supplied from the battery 36.
[0029]
The input terminals of the control device 31 include an ignition switch 35, an inside air temperature sensor 37 for detecting the inside air temperature, an outside air temperature sensor 38 for detecting the outside air temperature, a solar irradiation sensor 39 for detecting the amount of solar irradiation applied to the vehicle interior, and the heater core 11 Each signal is input from a water temperature sensor 40 for detecting the temperature of the water flowing into the inside, and a blow-off temperature sensor 41 provided on the downstream side of the air-conditioning case 2 and detecting the temperature of the blown air into the vehicle compartment.
[0030]
Signals from switches and levers of the control panel 42 are input to input terminals of the control device 31. As shown in FIG. 5, the switches and levers include an outlet mode setting switch 43 for setting an outlet mode, an inside / outside air switch 44 for setting an inside / outside air switching mode, and an air conditioner switch 45 for starting an air conditioner. A temperature setting lever 46 for setting a target temperature inside the vehicle compartment, and an air volume setting lever 47 for setting the volume of air blown into the vehicle interior.
[0031]
The signals from the sensors 37 to 41 are configured to be A / D converted by the A / D conversion circuit and then input to the microcomputer.
Control signals are output from the output terminal of the control device 31 to the blower motor 7, the solenoid valves 26 and 27, the outdoor fan 29, the inverter 30, the combustion heater 33, and the servo motors 48 to 50.
[0032]
Next, a control process of the combustion type heater 33 and the refrigeration cycle 8 performed by the microcomputer will be described based on a flowchart of FIG.
When power is supplied to the control device 31, the routine of FIG. 5 is started. Then, an initialization process is performed in the first step S10, and in the next step S20, a signal from the ignition switch 35, a signal from each of the sensors 37 to 41, and a signal from the control panel 42 are read. Then, in the next step S30, the on / off state of the ignition switch 35 is determined. If the ignition switch is determined to be off, this routine is exited, and if it is determined to be on, the process proceeds to the next step S40.
[0033]
In step S40, it is determined whether or not the outside air temperature detected by the outside air temperature sensor 38 is equal to or lower than a predetermined low outside air temperature (2 ° C. in the present embodiment). Here, when the determination is YES, the mode becomes a mode in which the refrigeration cycle 8 is stopped by operating the combustion type heater 33 by the processing of steps S50 to S90 described later, and when the determination is NO in step S40, By the process of step S100, the mode is set in which the refrigeration cycle 8 is operated to stop the combustion type heater 33.
[0034]
In step S50, the combustion type heater 33 is turned on. Specifically, power is supplied to the fuel pump 33d, the glow plug 33e, and the electric motor 33g. Then, in the next step S60, a target outlet temperature TAO to be blown into the vehicle compartment is calculated based on the following equation 1 stored in the ROM in advance.
[0035]
(Equation 1)
TAO = Kset × Tset−Kr × Tr−Kam × Tam−Ks × Ts−C
Here, Tset is the set temperature determined by the set position of the temperature setting lever 46, Tr is the inside air temperature detected by the inside air temperature sensor 37, Tam is the outside air temperature detected by the outside air temperature sensor 38, and Ts is the sunshine sensor 39. It is the detected solar radiation. Kset, Kr, Kam, and Ks are gains, respectively, and C is a constant.
[0036]
Then, in the next step S70, the temperature efficiency φ (V) of the heater core 11 is changed to the air volume V (m) determined by a target blower voltage described later (see FIG. 9). ³ / H).
Then, in the next step S80, a target water temperature TWO of the hot water flowing through the heater core 11 is calculated based on the following equation 2 stored in the ROM in advance. That is, the target hot water heating capacity of the combustion type heater 33 is calculated.
[0037]
(Equation 2)
TWO = (TAO−Tin) / φ (V) + Tin (° C.)
In other words, the target water temperature TWO is determined by the flow rate V (m ³ / H), the temperature of the air blown into the vehicle compartment is calculated to be the target air temperature TAO.
[0038]
Further, Tin in Expression 2 is the air temperature on the suction side of the heater core 11, and is calculated in the present embodiment based on Expression 3 below stored in the ROM in advance.
[0039]
(Equation 3)
Tin = α × Tam + (1−α) × Tr (° C.)
Here, α is a value set according to the inside / outside air mode, and α = 1 in the complete outside air introduction mode, and α = 0 in the complete inside air circulation mode.
Then, in the next step S90, the voltage applied to the fuel pump 33d and the electric motor 33g is controlled such that the water temperature TW detected by the water temperature sensor 40 becomes the target water temperature TWO. For example, if the detected water temperature TW is lower than the target water temperature TWO, the voltage applied to both the fuel pump 33d and the electric motor 33g is increased to increase the amount of combustion. Conversely, if the detected water temperature TW is higher than the target water temperature TWO, the voltage applied to both the fuel pump 33d and the electric motor 33g is reduced to reduce the amount of combustion.
[0040]
Also, in step S100, a deviation between TAO calculated by the above equation 1 and Tin calculated by the above equation 3 is calculated, and cooling and heating is performed based on this deviation and the map of FIG. Determine the operation mode.
Here, when the cooling operation is determined, the compressor 20 is operated, the electromagnetic valve 26 is opened, and the electromagnetic valve 27 is closed. As a result, the refrigerant in the refrigeration cycle 8 flows in the order of the compressor 20 → the refrigerant / water heat exchanger 21 → the outdoor heat exchanger 22 → the cooling expansion valve 24 → the indoor heat exchanger 9 → the accumulator 25 → the compressor 20 (FIG. (Indicated by a white arrow), and the cooling operation in which the indoor heat exchanger 9 functions as an evaporator is performed.
[0041]
When the heating operation mode is determined, the compressor 20 is operated, the electromagnetic valve 26 is closed, and the electromagnetic valve 27 is opened. Thereby, the refrigerant in the refrigeration cycle 8 is in the order of the compressor 20 → the refrigerant / water heat exchanger 21 → the heating expansion valve 23 → the outdoor heat exchanger 22 → the accumulator 25 → the compressor 20 (indicated by black arrows in the figure). Flows in In the heating operation mode, the power supply to the inverter 30 is controlled so that the water temperature TW detected by the water temperature sensor 40 becomes equal to the target water temperature TWO calculated by the above equation 2, whereby the air blown into the vehicle cabin is controlled. The temperature is adjusted.
[0042]
In addition, when the operation mode is determined to be the blowing operation mode, the compressor 20 is stopped. As a result, the air sucked from the inside air suction port 3 or the outside air suction port 4 is directly blown into the vehicle interior.
Next, control processing for air volume control performed by the microcomputer will be described with reference to the flowchart of FIG.
[0043]
When power is supplied to the control device 31, the routine of FIG. 8 is started. Then, in steps S110 to S140, the same processing as steps S10 to S40 in FIG. 6 is performed. If NO is determined in step S140, the process returns to step S120. If YES is determined, in next step S150, the blowout temperature TAR detected by blowout temperature sensor 41 and step S60 in FIG. Then, the magnitude relationship with the target outlet temperature TAO calculated in step (1) is determined.
[0044]
When it is determined in this step S150 that TAR <TAO + α, it means that (actual water temperature TW) <(target water temperature TWO + α ′) (α ′ is a constant), and the target hot water heating capacity of the combustion type heater 33 is Since the condition does not exceed the minimum capacity, in the next step S160, the target blower representing the target blown air amount of the blown air into the vehicle cabin based on the map indicated by the solid line in FIG. The voltage is calculated, and the target blower voltage is applied to the blower motor 7.
[0045]
Here, the map of FIG. 9 is a map for the mode in which the combustion heater 33 is operated, that is, the map for the heating operation. In a region where the target blowout temperature TAO is high, the target blower voltage becomes the maximum voltage Hi, The target blower voltage is set to decrease as the blowout temperature TAO decreases.
When it is determined in step S150 that TAR ≧ TAO + α (α is a constant), it means that (actual water temperature TW) ≧ (target water temperature TWO + α ′), and the target hot water heating capacity of the combustion type heater 33 is satisfied. Has exceeded the minimum capacity, the process proceeds to step S170 to control the blower voltage applied to the blower motor 7 so that the amount of air blown into the vehicle interior becomes a predetermined amount.
[0046]
Here, the predetermined air volume is an air volume corresponding to the target blower voltage calculated from FIG. 9 when the hot water heating capacity of the combustion heater 33 is the minimum capacity. Accordingly, the target blower voltage for setting the amount of air blown into the vehicle cabin to the predetermined amount of air is indicated by a dashed line in FIG. 9 and is a blower voltage higher than the blower voltage calculated based on TAO. .
[0047]
Next, a control process of the outlet mode control performed by the microcomputer will be described with reference to a flowchart of FIG.
When power is supplied to the control device 31, the routine of FIG. 10 is started. Then, in steps S210 to S250, the same processing as in steps S110 to S150 in FIG. 8 is performed. If the determination in step S250 is NO, it means that the target hot water heating capacity of the combustion type heater 33 is not a condition exceeding the minimum capacity. The air outlet mode is determined based on the map of No. 11, and the servo motor 50 is controlled as in the determined air outlet mode.
[0048]
Here, the foot mode (FOOT) is a mode in which the face air outlet 15 is closed and the foot air outlet 16 is opened to blow hot air mainly to the feet of the occupant, and the bi-level mode (B / L) is a face air blowing mode. A mode in which both the outlet 15 and the foot outlet 16 are opened to blow mainly cool air to the upper body of the occupant and mainly warm air to the feet, and the face mode (FACE) means that the face outlet 15 is opened and the foot outlet is opened. 16 is a mode in which the cold air is mainly blown out to the upper body of the occupant when the vehicle is closed.
[0049]
If it is determined in step S250 that TAR ≧ TAO + α (α is a constant), it means that the target hot water heating capacity of the combustion heater 33 has exceeded the minimum capacity, and in this case, step S270 Then, the servo motor 50 is controlled so that the outlet mode becomes the foot mode.
Next, the operation and effect of the present embodiment will be described based on experimental data shown in FIG.
[0050]
When the outside air temperature is 2 (° C.) or less (when the combustion type heater 33 is turned on) and the vehicle interior temperature is reduced to near the outside air temperature, the set temperature Tset is set to 25 (° C.). When the heating operation is performed at time 0 in FIG. 12, the target outlet temperature TAO is calculated as a high temperature, and based on this, the target water temperature TWO is also calculated as a high temperature.
[0051]
Then, by controlling the combustion type heater 33 so that the actual water temperature TW becomes the target water temperature TWO, the water temperature TW, the blow-out air temperature TAR, and the inside air temperature Tr 1 are increased. Then, as the vehicle interior warms, the target outlet temperature TAO and the target water temperature TWO gradually decrease, and the outlet air temperature TAR and the water temperature TW also decrease accordingly.
[0052]
Then, at time t1 in FIG. 12, YES is determined in step S150 in FIG. 8, and the control in step S170 is performed from this time. As a result, as shown by the solid line (1) in FIG. 12, the water temperature TW, the outlet air temperature TAR, and the inside air temperature Tr 1 change.
If the control of step S160 is performed when it is determined to be YES in step S150 of FIG. 8, and the vehicle is running at a speed of 40 (km / h), it is indicated by a solid line (2). At this time, the temperature did not exceed the temperature (110 ° C.) set for overheating protection of the combustion type heater 33, but when the car was stopped, the transition as shown by the broken line (3) was made. At time t2, the water temperature TW reached the set temperature for overheating protection, and the combustion heater 33 was stopped.
[0053]
Then, since it takes about three minutes before the time t3 when the combustion type heater 33 is operated next, the water temperature TW, the blow-out air temperature TAR, and the inside air temperature Tr 2 have been reduced during that time.
By the way, if the heating operation is being performed and YES is never determined in step S150 of FIG. 8, it changes as indicated by the solid line (4).
[0054]
As described above, according to the present embodiment, when the target hot water heating capacity of the combustion heater 33 exceeds the minimum capacity, the target blower voltage applied to the blower motor 7 is set to the blower indicated by the solid line in FIG. Since the blower voltage shown by the dashed line in FIG. 9 is used instead of the voltage, the amount of air blown into the vehicle cabin becomes the above-described predetermined amount of air. Therefore, since the excess heat given to the hot water by the combustion heater 33 is radiated by the heater core 11, the rise of the water temperature is suppressed, and the problem that the combustion heater 33 stops can be prevented.
[0055]
Further, when the target hot water heating capacity of the combustion heater 33 exceeds the above minimum capacity, even if the TAO is low, since the control is performed so as to fix in the foot mode, the warm air blows out to the occupant's face. Thus, it is possible to prevent the occupant from feeling uncomfortable.
(Other embodiments)
In the above embodiment, the heating capacity determining means according to the first aspect of the present invention is configured in step S150 of FIG. However, in steps S150 and S250, it may be determined whether or not (actual water temperature Tw) ≧ (target water temperature TWO + β), or (actual inside air temperature Tr) ≧ (set temperature Tset + γ). It may be determined whether or not this is the case. Here, β and γ are constants.
[0056]
In the above-described embodiment, it is determined in steps S150 and S250 whether or not the target hot water heating capacity of the combustion heater 33 exceeds the minimum capacity, and when it is determined that the condition is satisfied, the blowing is performed. The air volume is set to a predetermined air volume, and the outlet mode is fixed to the foot mode. However, the steps S150 and S250 are eliminated, and when the combustion type heater 33 is turned on, the blow air volume is controlled in a range not less than the predetermined air volume. Alternatively, the outlet mode may be fixed in the foot mode.
[0057]
Further, in the above embodiment, the predetermined air volume referred to in the first aspect of the invention is calculated as the air volume corresponding to the target blower voltage calculated from FIG. 9 when the hot water heating capacity of the combustion type heater 33 is the minimum capacity. However, it may be calculated so that the air volume becomes larger.
In the above embodiment, the mode of operating the combustion type heater 33 or the mode of operating the refrigeration cycle 8 is switched depending on whether the outside air temperature is 2 (° C.) or less. The cycle 8 may be eliminated, and the combustion type heater 33 may be always operated regardless of the outside air temperature.
[0058]
In the above embodiment, the air conditioner is used for an electric vehicle.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of an embodiment of the present invention.
FIG. 2 is a sectional view taken along the line AA of FIG. 1;
FIG. 3 is a partially enlarged sectional view of a combustion type heater 33 of the embodiment.
FIG. 4 is a block diagram of a control system of the embodiment.
FIG. 5 is a front view of a control panel 42 of the embodiment.
FIG. 6 is a flowchart showing control processing for the combustion heater 33 and the refrigeration cycle 8 performed by the microcomputer of the embodiment.
FIG. 7 is a map for a cooling / heating operation mode of the embodiment.
FIG. 8 is a flowchart showing a control process for air volume control performed by the microcomputer.
FIG. 9 is a map for a target blower voltage of the embodiment.
FIG. 10 is a flowchart showing a control process for an outlet mode control performed by the microcomputer.
FIG. 11 is a map for an outlet mode of the embodiment.
FIG. 12 is a diagram showing experimental data on changes in water temperature, blown air temperature, and inside air temperature.
[Explanation of symbols]
2 ... air-conditioning case (air passage), 3 ... inside air suction port (air suction port),
4 ... outside air suction port (air suction port), 6 ... fan (blowing means), 8 ... refrigeration cycle,
10 hot water circuit (circulation circuit), 11 heater core (heat exchanger for heating),
15 ... face outlet (outlet), 16 ... foot outlet (outlet),
18 door (air outlet opening / closing means), 19 door (air outlet opening / closing means),
33: Combustion heater (combustion device).

Claims (4)

An air passage (2) having an air intake port (3, 4) formed at one end side and an air outlet (15, 16) formed at the other end side for blowing air into a vehicle cabin;
Blower means (6) for generating an air flow from the one end to the other end in the air passage (2);
A heating heat exchanger (11) that is provided in the air passage (2) and heats the air in the air passage (2) by heat exchange with a heat medium flowing therethrough;
A circulation circuit (10) through which a heat medium circulates through the heating heat exchanger (11);
A combustion device (33) provided so as to be capable of exchanging heat with the heat medium in the circulation circuit (10), heating the heat medium by burning fuel, and adjusting its heating capacity within a predetermined minimum capacity or more; When,
Target outlet temperature calculating means (S60) for calculating a target outlet temperature of the air blown into the vehicle interior;
A target blowing air amount calculating means (S160) for calculating a target blowing air amount of the blowing air into the vehicle cabin so as to decrease with a decrease in the target blowing temperature during the heating operation;
Target heating capacity calculating means for calculating a target heating capacity of the combustion device (33) such that the temperature of the air blown into the vehicle compartment becomes the target blown temperature when the amount of air blown into the vehicle interior is the target blown air volume. (S80), during the heating operation, the combustion device (33) is controlled such that the heating capacity of the combustion device (33) becomes the target heating capability, and the amount of air blown into the vehicle interior is reduced to the target volume. An air conditioner for a vehicle that controls the blowing means (6) so as to have a blowing air volume,
When the target heating capacity of the combustion device (33) is less than the minimum capacity, the amount of air blown into the vehicle compartment is set to a predetermined airflow larger than the airflow calculated by the target airflow calculation means (S160). An air conditioner for a vehicle, characterized by controlling the blowing means (6). A heating capacity determination unit (S150) for determining whether or not the target heating capacity of the combustion device (33) is less than the minimum capacity;
When the target heating capacity is determined to be lower than the minimum capacity by the heating capacity determination means (S150), the amount of air blown into the vehicle compartment is determined from the amount of air calculated by the target amount of air flow calculation means (S160). The vehicle air conditioner according to claim 2, wherein the air blowing means (6) is controlled so as to have a large predetermined air volume. An air inlet (3, 4) is formed at one end, a face outlet (15) that blows air to the upper body of the passenger in the passenger compartment, and a foot outlet (15) that blows air to the feet of the passenger in the passenger compartment at the other end. 16) an air passage (2) formed with;
Outlet opening and closing means (18, 19) for opening and closing the face outlet (15) and the foot outlet (16);
Blower means (6) for generating an air flow from the one end to the other end in the air passage (2);
A heating heat exchanger (11) that is provided in the air passage (2) and heats the air in the air passage (2) by heat exchange with a heat medium flowing therethrough;
A circulation circuit (10) through which a heat medium circulates through the heating heat exchanger (11);
A combustion device (33) provided so as to be capable of exchanging heat with the heat medium in the circulation circuit (10), heating the heat medium by burning fuel, and adjusting its heating capacity within a predetermined minimum capacity or more; When,
Target outlet temperature calculating means (S60) for calculating a target outlet temperature of the air blown into the vehicle interior;
Target heating capacity calculating means for calculating a target heating capacity of the combustion device (33) such that the temperature of the air blown into the vehicle compartment becomes the target blown temperature when the amount of air blown into the vehicle interior is the target blown air volume. (S80),
A foot mode in which the face outlet (15) is closed and the foot outlet (16) is opened as the target outlet temperature changes from a higher one to a lower one. An outlet mode calculating means (S260) for calculating an outlet mode so as to be a level mode, a face mode in which the face outlet (15) is opened and the foot outlet (16) is closed, and in the heating operation, Controlling the combustion device (33) so that the heating capacity of the combustion device (33) becomes the target heating capability, and setting the combustion device (33) to the outlet mode calculated by the outlet mode calculation means (S260). A vehicle air conditioner for controlling the outlet opening / closing means (18, 19),
When the target heating capacity of the combustion device (33) is lower than the minimum capacity, the air outlet opening / closing means (18, 19) is controlled to be in the foot mode. . A heating capacity determination unit (S250) for determining whether the target heating capacity of the combustion device (33) is less than the minimum capacity;
When the heating capacity determining means (S250) determines that the target heating capacity is less than the minimum capacity, controlling the air outlet opening / closing means (18, 19) to be in the foot mode. The vehicle air conditioner according to claim 3, wherein:

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