JPH07186690A - Air quantity controller for air conditioner for vehicle - Google Patents

Abstract

PURPOSE:To suppress the increase of the air quantity and maintain the excellent air conditioning feeling by judging the shortage of the air conditioning faculty when the driving state of an air conditioner device is under a high thermal load environment in a stable state, and by regulating the upper limit of the blower fan voltage. CONSTITUTION:A control means 10 calculates the target blow-out temperature according to a program set by a microcomputer, from the signals of the sensors 11, 13-15 for the inside air, outside air, solar radiation and an evaporator, and the signal of a room temperature setting device 12, and outputs the blower fan voltage which is determined according to the above-described calculation, into a blower fan motor 9. Herein when it is judged that an air conditioner is in a stationary state, from the fact that the difference between the detected room temperature and the set temperature is within a prescribed range, and the target blow-out temperature is below the detected temperature, the generation of the high thermal load environment in a stable state is judged, and the increase of the blower fan voltage at present which is supplied to the drive circuit of the blower fan motor 9 is regulated. Accordingly, even in case of stagnation, etc., the rise of the temperature inside the car room due to the increase of the air quantity is suppressed, and the excellent feeling can be maintained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air volume control device for an air conditioner for a vehicle, which controls the air volume blown into the vehicle compartment according to the detected room temperature in the vehicle compartment, the set room temperature, the detected outside air temperature outside the vehicle compartment, and the like.

[0002]

2. Description of the Related Art A conventional vehicle air conditioner is disclosed in, for example, JP-A-4-283116, JP-A-2-299920, JP-A1-223016, and JP-A-62-6832. The target temperature is calculated from the detected room temperature in the passenger compartment, the set room temperature in the passenger compartment, and the outside air temperature outside the passenger compartment, and the blower fan voltage is determined from the predetermined temperature according to this target temperature to blow air into the passenger compartment. An air volume control device for controlling the air volume is known.

[0003]

In this conventional air volume control device for a vehicle air conditioner, for example, when cooling the air conditioner while the driving condition of the air conditioner is stable, the target temperature becomes equal to or lower than the evaporator outlet temperature immediately after passing through the evaporator. Then, the blower fan voltage is increased to increase the air volume of the conditioned air blown into the vehicle interior so that the air conditioning state in the vehicle interior becomes the target air conditioning state. In a high heat load environment where the cooling capacity of the air conditioner is not sufficient for the heat load, the cooling capacity of the evaporator is reduced even if the air volume is increased, so the temperature of the cool air immediately after passing through the evaporator, that is, the temperature at which the evaporator blows out, rises. As a result, the room temperature in the passenger compartment rises. Then, the room temperature of the inside air sensor is fed back to the control device, and the target temperature becomes lower and the air volume further increases, leading to a vicious circle. There is an inherent problem that the room temperature further rises due to the increase in the air volume due to this vicious circle, the blower fan voltage reaches the maximum value in a predetermined pattern, and the feeling of the air-conditioning state in the vehicle interior deteriorates.

The present invention has been made to solve the above problems. When the air conditioner is in a stable driving state and the cooling capacity of the air conditioner is insufficient with respect to the heat load in the passenger compartment,
An object of the present invention is to provide an air volume control device for an air conditioning system for a vehicle, which suppresses an increase in the air volume and maintains a good feeling of an air conditioning state in a vehicle interior.

[0005]

[Means for Solving the Problems]

The air volume control device for a vehicle air conditioner according to the present invention determines the blower fan voltage according to the target temperature calculated from the detected room temperature in the vehicle compartment, the set room temperature and the outside air temperature outside the vehicle compartment, and blows it out into the vehicle compartment. The control means controls the upper limit of the blower fan voltage by determining the lack of air conditioning capacity when the driving condition of the air conditioner is stable and placed in a high heat load environment. It is configured.

[0007]

The air volume control device for the vehicle air conditioner of the present invention is
When the operation of the air conditioner is started, the conditioned air according to the target blowout temperature is blown from the air conditioner into the vehicle compartment, and the drive state of the air conditioner is in a steady state, for example, the target blowout temperature immediately after passing through the evaporator. When the temperature is below the blowout temperature and the cooling capacity of the air conditioner is placed in a high heat load environment where the heat load in the passenger compartment is insufficient, the blower fan voltage supplied to the drive circuit of the blower fan motor should not rise above the current value. regulate.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An air flow controller for a vehicle air conditioner as an embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a block diagram showing an air volume control means of a vehicle air conditioner of this embodiment, FIG. 2 is an air volume estimation map of this embodiment, and FIG. 3 is a block diagram showing a vehicle air conditioner of this embodiment. .

In FIG. 3, an air conditioner for a vehicle has a duct 1 which constitutes the main body of the apparatus, and an upstream side of the duct 1 is an outside air introduction port 2 for introducing outside air outside the passenger compartment and an inside air inside the passenger compartment. It has an inside air introduction port 3 and an intake door 4 that opens and closes both of these introduction ports 2 and 3. The duct 1 on the downstream side of the intake door 4 sucks air from both the introduction ports 2 and 3 to form a duct. 1 has a blower fan 5 for blowing air to the downstream side, and the air blown from the blower fan 5 is supplied to the duct 1 on the downstream side of the blower fan 5 from a compressor (not shown) driven by an engine (not shown). Has an evaporator 6 that cools with the refrigerant, and a duct 1 on the downstream side of the evaporator 6 has a heater core 7 that heats the cold air cooled by the evaporator 6 with the cooling water of the engine,
In the duct 1 between the heater core 7 and the evaporator 6, there is an air mix door 8 for adjusting the ratio of the amount of air that bypasses the heater core 7 of the cool air cooled by the evaporator 6 and the amount of air that is sent to the heater core 7. Also the evaporator 6
The temperature of the air cooled by
It is usually maintained by turning the compressor on and off at about 3 ° C. This temperature is called the target evaporation temperature. Although not shown in the drawings, an air mix chamber that creates an air-conditioned air that is a mixture of the cool air that bypasses the heater core 7 and the warm air that is warmed by the heater core 7, a defroster duct that blows the air-conditioned air toward the window glass in the passenger compartment, It has a vent duct that blows the conditioned air from the chest of the passenger in the passenger compartment toward the upper part, a heat duct that blows the conditioned air toward the feet of the passenger in the passenger compartment, and the like. The control means 10 controls an intake door actuator (not shown) that opens and closes the intake door 4, a blower fan motor 9 that rotates the blower fan 5, and an air mix door actuator (not shown) that opens and closes the air mix door 8. This control means 1
0 indicates an inside air sensor 11, a room temperature setting device 12, and an outside air sensor 1.
3, the solar radiation sensor 14, the evaporator sensor 15 and the like are connected. The inside air sensor 11 is a room temperature Ti in the passenger compartment.
nc is detected, and a signal corresponding to the detected room temperature Tinc is output to the control means 10. The room temperature setting device 12 controls the signal according to the set room temperature Tset in the passenger compartment set by the passenger.
Output to 0. The outside air sensor 13 is an outside air temperature Ta outside the vehicle compartment.
mb is detected, and a signal according to the detected outside air temperature Tamb is input to the control means 10. The solar radiation sensor 14 detects the solar radiation amount Tsun outside the vehicle compartment, and outputs a signal corresponding to the detected solar radiation amount Tsun to the control means 10. The evaporator sensor 15 detects the blowing temperature Teva as the temperature of the air blown from the evaporator, and outputs a signal according to the detected blowing temperature Teva to the control means 10.
The control means 10 is composed of a microcomputer,
Detection of room temperature T by a preset program
The target blowout temperature as the target temperature is calculated from the inc and the set room temperature Tset, the outside air temperature Tamb, and the thermal environment information inside and outside the vehicle such as the solar radiation amount Tsun, and the blower fan voltage Vfan is determined according to the target blowout temperature, and this determination is made. The blower fan voltage Vfan is output to the blower fan motor 9 to control the amount of conditioned air blown into the vehicle interior.

In FIG. 1, the control means 10 includes an air conditioning operation state detection means 20, a high heat load detection means 21, a suction temperature estimation means 22, an air volume estimation means 23, a cooling capacity estimation means 24, an outlet temperature estimation means 25, and a first air temperature estimation means 25. 1st stable room temperature calculating means 26, 2nd stable room temperature calculating means 27, comparing means 28 and voltage increase regulating means 29, and intake door opening IDT and detected room temperature Tinc as control signals for determining the drive of the intake door actuator. Judgment of insufficient air conditioning capacity when the air conditioner is operating in a stable and high heat load environment based on thermal environment information such as set room temperature Tset, outside air temperature Tamb, blower fan voltage Vfan, solar radiation amount Tsun, and detection outlet temperature Teva. Then, the upper limit of the blower fan voltage is regulated.

The air-conditioning operation state detecting means 20 detects, for example, when the temperature difference between the detected room temperature Tinc and the set room temperature Tset is within a predetermined specified range, as if the drive state of the air conditioner is a steady state. Alternatively, when the elapsed time from the start of operation of the air conditioner exceeds a predetermined specified time, the drive state of the air conditioner is detected as a steady state, and the steady state detection signal is output to the high heat load detection means 21. .

The high heat load detecting means 21 compares the target blow-out temperature, the detected blow-out temperature Teva and the target evaluation blow-out temperature, and the detected blow-out temperature is equal to or higher than the target evaluation blow-out temperature and the target blow-out temperature is the detected discharge temperature T.
When it is eva or less, a high heat load detection signal is output to the suction temperature estimation means 22 and the air volume estimation means 23.

The intake temperature estimation means 22 is provided with the intake door opening IDT, the detected room temperature Tinc, and the detected outside air temperature T.
Estimated suction temperature Tint as the temperature of the air sucked into the evaporator 6 from the inside / outside air inlet side from amb
Is calculated and output to the cooling capacity estimation means 24 and the blowout temperature estimation means 25. When the intake door opening IDT is a recycle signal in which the outside air inlet 2 is closed and the inside air inlet 3 is opened, the intake estimation means 22 uses the detected room temperature Tinc as the intake estimated temperature Tint as it is, and the intake door opening IDT Is a fresh signal in which the outside air introduction port 2 is opened and the inside air introduction port 3 is closed, a temperature (for example, outside air temperature + 5 ° C.) obtained by adding a constant temperature such as 5 ° C. to the outside air temperature Tamb is sent to the evaporator 6. It is calculated as the estimated suction temperature Tint.

The air flow rate estimating means 23 uses an intake door opening I
The air volume generated by the rotation of the blower fan 5 is estimated and calculated from DT and the blower fan voltage Vfan determined from the target blowout temperature and output to the cooling capacity estimation means 24 and the second stable room temperature calculation means 27. The air volume estimation means 23 stores an air volume estimation map 31 as shown in FIG. 2 in advance. This air volume estimation map 31 shows the blower fan voltage Vfan on the horizontal axis and the blower fan air volume vfan on the vertical axis, and recycles the blower fan air volume vfan with respect to the blower fan voltage Vfan when the intake door opening IDT is a recycle signal. Characteristic 3
2 and a fresh characteristic 33 that defines the blower fan air volume vfan with respect to the blower fan voltage Vfan when the intake door opening IDT is a fresh signal.
When the recycle signal is input as the intake door opening IDT, the air volume estimating means 23 extracts the blower fan air volume vfan from the recycle characteristic 32 according to the input blower fan voltage Vfan, and the fresh signal as the intake door opening IDT. Is input, the blower fan air flow rate vfan is extracted from the fresh characteristic 33 in accordance with the input blower fan voltage Vfan, and a signal corresponding to the extracted blower fan air flow rate vfan is output as the estimated air flow rate vfan.

The cooling capacity estimating means 24 estimates the cooling capacity by utilizing the fact that the heat quantity of the air changed before and after passing through the evaporator 6 corresponds to the cooling capacity of the air conditioner, that is, the cooling capacity of the evaporator 6. = R · Cp · vfan (Tint-Teva)
……… The arithmetic expression 1 is stored in advance. In this calculation formula 1, Qeva: Estimated cooling capacity (kcal / s) r: Specific gravity of air (kg / m3) Cp: Specific heat of air (kcal / kg · ° C) vfan: Estimated air volume (m3 / s) Tint: Estimated suction temperature (° C) Teva: Detection blow temperature (° C). In this cooling capacity estimating means 24, constants determined from general physical quantities are entered as the specific gravity r of air and the specific heat Cp of air in the above-mentioned arithmetic expression 1, and the air volume estimating means 23 is added to vfan in this arithmetic expression 1. Estimated air volume v received from
Substituting fan, the estimated suction temperature Tint received from the suction estimation unit 22 in Tint in the arithmetic expression 1.
Is substituted, the detected outlet temperature Teva is substituted for Teva in the arithmetic expression 1, the estimated cooling capacity Qeva is estimated and calculated, and is output to the outlet temperature estimation means 25.

The blowout temperature estimating means 25 calculates the estimated blowout temperature Tevamax in order to estimate the temperature of the air immediately after passing through the evaporator when the blower fan voltage Vfan reaches the maximum value maxHi. Tevamax = -Qeva / (r · Cp · vfanm
ax) + Tint ......... 2 The arithmetic expression 2 is stored in advance. In the blowout temperature estimating means 25, a constant determined from a general physical quantity is entered as the specific gravity r of air and the specific heat Cp of air in the above-mentioned arithmetic expression 2, and the intake door opening degree is added to vfanmax in this arithmetic expression 2. The maximum air volume vfanmax extracted from the air volume estimation map 31 for the maximum value maxHi of the blower fan voltage Vfan according to the IDT is substituted, and the estimated suction temperature Tint received from the suction estimation means 22 is substituted for Tint in the arithmetic expression 2. , The estimated maximum outlet temperature Tevamax when the blower fan voltage Vfan reaches the maximum value maxHi is calculated and output to the first room temperature calculating means 26.

In the first room temperature calculating means 26, the heat balance in the passenger compartment in the steady state is Qac + Qsun + Qmen + Qtra + Qdra = 0.
……………………………………………………………………………………………………………………………………………… 3 3
This is the calculation of max.
Is stored in advance. In this calculation formula 3, Qac: Heat quantity difference of the air blown into the passenger compartment from the air-conditioning system with respect to room temperature Qsun: Heat quantity due to the amount of solar radiation Qmen: Heat quantity generated by the occupant Qtra: Heat transfer from outside air Qdra: Air conditioning It is the difference in heat value with respect to room temperature of the air that enters the passenger compartment from outside the blow-out duct of the equipment. In addition, Qac = r · Cp · vfanmax (Tevamax−
4 Qtra = h0 (Tamb-Troommax), where h0 is the heat transfer coefficient of the vehicle ... 5 Qdra = r.Cp.vdra (Tamb-Troom)
max), where vdra is the amount of air entering the vehicle interior from other than the blowout duct 1 of the air conditioner. In the first room temperature calculating means 26, a constant determined from a general physical quantity is inserted as the specific gravity r of air and the specific heat Cp of air in the arithmetic expression 4, and vf in the arithmetic expression 4 is entered.
Substituting the maximum air volume vfanmax received from the air volume estimation map 31 according to the intake door opening IDT for anmax, and estimating when the blower fan voltage Vfan received from the blowout temperature estimation means 25 becomes maximum in Tevamax in the arithmetic expression 4. Estimated maximum temperature Tevam
Substituting ax, the maximum estimated room temperature Roommaxmax in the vehicle interior when the blower fan voltage Vfan reaches the maximum value maxHi is estimated and output to the comparison means 28.

Since the second room temperature calculating means 27 estimates and calculates the present room temperature of the vehicle by utilizing the fact that the heat balance in the vehicle interior in the steady state is satisfied by the above equation (3) as an equilibrium condition. Stores the above-mentioned arithmetic expression 3 in advance. In the arithmetic expression 3, Qac = r · Cp · vfan (Teva-Troom)
……… 7 Qtra = h0 (Tamb-Troom) ………… 8 Qdra = r · Cp · vdra (Tamb-Troo)
m) ......... 9. In the second room temperature calculating means 27, constants determined from general physical quantities are entered as the specific gravity r of air and the specific heat Cp of air in the arithmetic expression 7, and vf in the arithmetic expression 7 is set.
An estimated air volume vfa received from the air volume estimation unit 23
Substituting n, and substituting the detected blow-out temperature Teva into Teva in the arithmetic expression 7, the current estimated room temperature Troom in the vehicle compartment in which the drive state of the air conditioner is in a steady state is estimated and calculated and output to the comparison means 28.

The comparison means 28 is the maximum estimated room temperature Troommax from the first room temperature calculation means 26 and the second room temperature calculation means 2.
Comparing with the current estimated room temperature Room in the passenger compartment from 7
Maximum estimated room temperature Troommax is currently estimated room temperature Troo
When it is higher than m, it is determined that the cooling capacity of the air conditioner is insufficient, and the determination result is output to the voltage increase regulating means 29.

The voltage increase regulating means 29 determines the present blower fan voltage Vfan to the blower fan motor 9 based on the result of the comparison result from the comparing means 28 that the cooling capacity of the air conditioner is insufficient.
Is set as an upper limit value, and a signal for controlling the increase of the current blower fan voltage Vfan is output to a drive circuit (not shown) of the blower fan motor 9.

Next, the operation of the air volume control device of the vehicle air conditioner of the above embodiment will be described. The operation of the air conditioner is started,
The control unit 10 determines the blower fan voltage Vfan according to the target blowout temperature calculated from the thermal environment information inside and outside the vehicle compartment, outputs the determined blower fan voltage Vfan to the drive circuit of the blower motor 9, and blows it out into the vehicle compartment. For example, whether the temperature difference between the detected room temperature Tinc and the set room temperature Tset is within a predetermined specified range or the elapsed time from the start of operation of the air conditioner is a specified time When it is detected that the driving state of the air conditioner is in a steady state by exceeding the target temperature, the target outlet temperature and the detected outlet temperature Teva are detected.
Compare with. When the target outlet temperature is equal to or lower than the detected outlet temperature Teva, it means that the driving state of the air conditioner is stable and placed in a high heat load environment.
Current estimated intake temperature Tint from intake door opening IDT, detected room temperature Tinc, and detected outside air temperature Tamb
And the estimated air volume vfan from the intake door opening IDT and the blower fan voltage Vfan.
The current estimated cooling capacity Qeva is estimated and calculated from the estimated air volume vfan and the estimated intake temperature Tint, and the estimated blowout temperature Tevamax at the maximum value maxHi of the blower fan voltage Vfan is estimated from the current estimated cooling capacity Qeva and the maximum air volume vfanmax. The maximum estimated room temperature Roomommax in the vehicle interior when the blower fan voltage Vfan reaches the maximum value maxHi is estimated and calculated from the estimated blowout temperature Tevamax, while the current estimated room temperature in the vehicle compartment is calculated from the estimated air volume vfan and the detected blowout temperature Teva. Estimate and calculate the Room. This maximum estimated room temperature Troommax is the currently estimated room temperature Troo.
When it is higher than m, it means that the cooling capacity of the air conditioner is insufficient, so that the control means 10 regulates the rise of the current blower fan voltage Vfan being supplied to the drive circuit of the blower fan motor 9. . As a result, even in a high heat load environment in which the drive condition of the air conditioner is stable, the target outlet temperature is equal to or lower than the outlet temperature immediately after passing through the evaporator 6, and the cooling capacity of the air conditioner is insufficient for the heat load in the passenger compartment, Since the blower fan voltage Vfan does not rise above the current value, the amount of conditioned air blown from the duct 1 of the air conditioner into the passenger compartment does not increase. Therefore, even when the cooling capacity of the air conditioner is not sufficient for the heat load in the passenger compartment, such as during traffic congestion, the room temperature in the passenger compartment may rise due to the increase in the air volume when the cooling capacity of the evaporator 6 is reduced. It can be prevented, and a good feeling of air conditioning can be secured.

Note that vdr in the above equations 6 and 9
a is different depending on the state of the vehicle body door closed, the vehicle body door opening degree, the window window opening degree, etc., but the air volume assuming each state was experimentally determined and an approximate value based on the obtained air volume was used as a guide. Should be calculated. Also,
In the above embodiment, as an example, the room temperature at which the blower fan voltage Vfan has the maximum value maxHi is set as the first estimated room temperature, but this may be set as the estimated room temperature at the blower fan voltage Vfan or the blower fan air volume vfan which is higher than the present value by a predetermined value.

[0024]

As described above, according to the present invention,
In the state where the driving state of the vehicle air conditioner is in a steady state, for example, the target blowout temperature becomes equal to or lower than the blowout temperature immediately after passing through the evaporator, and the cooling capacity of the air conditioner becomes a high heat load environment insufficient for the heat load in the vehicle interior. When it is installed, the blower fan voltage supplied to the drive circuit of the blower fan motor is regulated so that it does not rise above the current value. Even if the cooling capacity is not sufficient, it is possible to prevent the room temperature from increasing in the vehicle interior due to the increase in the air volume, and it is possible to ensure a good feeling in the air-conditioned state. As a result, the inconvenience of divergence control being taken when a target value exceeding the capacity limit is taken, for example, when the room temperature in the vehicle compartment is controlled by the servo system driven by the opening of the air mix door and the blower fan voltage, is eliminated. In addition, there is an advantage that suitable cool-down initial control can be achieved without performing delay control of the blower fan at the initial stage of cool-down.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an air volume control means of an air conditioner of an embodiment.

FIG. 2 is an air volume estimation map of the embodiment.

FIG. 3 is a configuration diagram showing an air conditioner of an embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Duct which comprises the apparatus main body 5 Blower fan 6 Evaporator 10 Control means 20 Air conditioning operating state detection means 21 High heat load detection means 22 Suction temperature estimation means 23 Air volume estimation means 24 Cooling capacity estimation means 25 Outlet temperature estimation means 26 1st stable room temperature Calculation means 27 Second stable room temperature calculation means 28 Comparison means 29 Voltage increase regulation means

Claims (1)

[Claims] 1. A target temperature is calculated from the detected room temperature in the vehicle compartment, the set room temperature in the vehicle compartment, the detected outside air temperature outside the vehicle compartment, and the like,
In an air volume control device for a vehicle air conditioner that determines the blower fan voltage according to this target temperature and controls the air flow rate of the air conditioning air blown into the vehicle compartment, when the drive condition of the air conditioner is stable and placed in a high heat load environment. An air flow control device for an air conditioning system for a vehicle, comprising a control means for determining an upper limit value of a blower fan voltage by judging insufficient air conditioning capacity.