JPH0742825Y2 - Vehicle air conditioner - Google Patents

Description

[Detailed description of the device] [Industrial applications]

The present invention relates to a vehicle air conditioner, and more particularly to improvement of a vehicle air conditioner that controls a vehicle defroster.

[Prior art]

Generally, a vehicle air conditioner is a device mounted on a vehicle in order to make the temperature, humidity and the like in the vehicle compartment comfortable and to make the living space of the driver preferable. In the early morning of winter, when the front window is frozen when starting the engine, melting the frost and ice stuck to the outer surface of the front window (defrost) is essential for safe driving, and is important for the air conditioning system. It is one of the important functions.
At the same time, the air inside the vehicle is humidified by steam generated by humans, and when the surface temperature inside the glass surface of the front window becomes lower than the dew point temperature of the air inside the vehicle, clouding or freezing due to condensation of water droplets inside the glass surface occurs. Sometimes it happens.
In the air conditioner, it is necessary to temporarily blow most of the heating air to the glass surface (hereinafter, referred to as defroster) in order to clear up such fogging and freezing (demist, defog, deice). At the same time, it is necessary to blow a small amount of some heating air from the defroster nozzles to the extent that clouding does not occur even during heating and constantly blow it onto the window glass. When performing the defroster operation (hereinafter, referred to as defroster mode) for the control related to the air conditioner as described above, an outside air temperature sensor that detects the outside air temperature, a vehicle interior temperature sensor that detects the inside temperature of the vehicle, and an irradiation amount of sunlight There is one that is controlled by using a solar radiation sensor that detects the. In this control, from the detected outside air temperature, vehicle interior temperature and solar radiation amount, and the set temperature set by the temperature setter, the target outlet temperature required to bring the vehicle interior temperature to the set temperature is calculated, When the target outlet temperature is high and the heating load is large, or when the target outlet temperature is low and the cooling load is large, a large amount of air is blown out.On the other hand, when the target outlet temperature is in the middle region with a small heating load or a small cooling load, , There is a control to blow out a small amount of air. By the way, in the above control, when the defroster tries to melt the freezing of the front window when the engine is started in the winter when the outside air temperature is low, the heating load is large and the target outlet temperature is high, so that a large amount of air is blown out.
However, when the engine cooling water temperature is low, such as when starting the engine in winter, the blowing temperature is low even if a large amount of air is blown, the temperature of the glass surface does not rise so much, and the melting of the freezing of the glass surface becomes slow. . From the above, according to the environmental conditions such as the engine cooling water temperature, the ice on the glass surface of the front window can be melted most quickly. That is, it can be seen that there is an air volume that can maximize the rate of temperature rise on the glass surface. Regarding the technology for obtaining the air volume that maximizes the temperature rise rate, there is a method for controlling a car air conditioner disclosed by the applicant in Japanese Patent Laid-Open No. 57-138414. In this control method, in the defroster mode, when the outside air temperature is below the reference value and an air volume above the predetermined value is desired, the target outlet temperature is reset to a higher reference value. However, in the above control method, when the engine is started in winter, the temperature of the engine cooling water has not risen so much, so the air blown by fully opening the air mix damper is warmed by the heater core. Even if the temperature reference value is set higher, the opening degree of the air mix damper does not change and the actual blowout temperature does not become higher. Therefore, in the above control method, it is effective when the engine cooling water temperature is sufficiently raised, but it is not effective when the engine cooling water temperature is not yet sufficiently raised at the time of engine start in winter. Another technique is to change the opening of a damper that controls the air volume of the defroster outlet in the heater mode according to the engine cooling water temperature when the engine cooling water temperature has not risen sufficiently. is there. That is, the distribution of the air volume blown out from the defroster air outlet and the air volume blown out from the heater air outlet for sending the warmed air into the vehicle compartment is changed to perform the defroster.
Specifically, when the engine cooling water temperature is low, the amount of air blown from the heater outlet is decreased and the amount of air blown from the defroster outlet is increased. On the other hand, when the engine cooling water temperature is high, the amount of air blown from the heater outlet is increased and the amount of air blown from the defroster outlet is decreased. Because it blows out from both outlets, it freezes the ice on the glass surface of the wind slowly.

[Problems to be solved by the device]

As described above, conventionally, there is no vehicle air conditioner capable of obtaining the optimum defrost air volume according to the engine cooling water temperature, environmental conditions, etc., and obtaining the air volume capable of quickly melting the frost on the glass surface of the predetermined window. There is a problem. In addition, as a technology related to the present invention
There are JP-A-58-122216, JP-A-58-97512 and the like, but these are for controlling the air blowing temperature when the engine cooling water temperature is sufficiently high in the heater mode, and in the technology for solving the above problems Absent.

[The purpose of the device]

The present invention has been made to solve the above-mentioned conventional problems, in which the fan air flow rate is controlled to maximize the rate of increase of the glass surface temperature of a predetermined window at the time of engine start,
It is an object of the present invention to provide an air conditioning system for a vehicle that can obtain the maximum defrosting effect and quickly melt ice on the glass surface.

[Means for solving problems]

The present invention provides a ventilation duct having a plurality of outlets including a defroster outlet for blowing air toward a glass surface of a predetermined window and an air intake, a damper for opening and closing the defroster outlet, and A blower fan for flowing air through the ventilation duct, a drive motor for rotationally driving the blower fan, a heating heat exchanger for heating the air flowing through the ventilation duct, and an outside air temperature t _o are detected. an outside air temperature sensor for a vehicle interior temperature sensor for detecting the vehicle interior temperature t _r, the air conditioning system and the water temperature sensor, is provided for detecting an engine coolant temperature t _w, said glass In the defroster mode in which the glass surface temperature sensor for detecting the surface temperature t _g and the defroster outlet is opened, the detected engine cooling water temperature t _w
When is less than a predetermined value, the outside air temperature t _o is detected by each sensor, the vehicle interior temperature t _r, depending on the engine coolant temperature t _w and the glass surface temperature t _g, at position l along the glass surface of the window Defroster jet temperature t _s and glass surface temperature t _g
And, based on the calculation in consideration of the heat balance according to the outside air temperature t _o , the target air flow rate W at which the increase rate of the glass surface temperature t _g is maximum is calculated, and the air flowing through the air blow duct is calculated. The above object is achieved by including a control circuit that controls the rotation speed of the drive motor so as to achieve the target air flow rate W.

[Action]

In the present invention, in the vehicle air conditioner, detects the glass surface temperature t _g of a given window glass surface temperature sensor, it shall apply in defroster mode defroster air outlet is opened, the detected coolant temperature t _w when more than a predetermined value, the outside air temperature detected by the sensors t _o, vehicle interior temperature t _r, the engine cooling water temperature t _w and the target air volume W according to the glass surface temperature t _g
Is calculated, and the rotation speed of the drive motor is controlled so that the air flowing through the blower duct becomes the calculated target blown air amount W. In particular, as shown at position l along the glass surface of the window従Tsutanetsu balance temperature t _s and the glass surface temperature t _g and the outside air temperature t _o the defroster jets, for example (7) of the embodiment described later Control is performed so that the target air flow rate W is calculated based on a calculation in consideration of various heat balances. Therefore, the fan air flow rate W is controlled to maximize the rate of increase of the glass surface temperature t _g of the predetermined window in accordance with the environmental temperature such as the engine cooling water temperature t _w , and the maximum defrost effect is obtained to obtain the glass surface. The freezing can be quickly thawed. Particularly, by considering the heat balance as described above, it becomes possible to control the air flow rate W more quantitatively and more accurately. Yotsutte
The freezing of the glass surface can be quickly melted when the engine cooling water temperature t _w just after starting the engine in winter is still not sufficiently high. For this reason, the visibility of the occupant is promptly improved, and the vehicle can be started quickly.
This effect is particularly great on the glass surface of the front window.

【Example】

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. This embodiment is a vehicle air conditioner having a structure as shown in FIG. This air conditioner has a ventilation duct 10 for blowing air, which is provided at an appropriate position on the vehicle. At one end of the ventilation duct 10, an outside air intake 10 and an inside air intake 14 which are air intakes.
Are provided, and one of these inlets is selectively opened by the inside / outside air damper and the other is closed. The outside air is taken in in the state shown by the solid line (shown by reference numeral 16A) and the inside air is shown in the state shown by the chain line (shown by reference numeral 16B) in the figure. Immediately after each of the air intakes 12 and 14, there is provided a blower fan 30 which is rotationally driven by a drive motor 28. The blower fan 30 is rotationally driven and air is blown toward the evaporator 32 installed in the middle portion of the ventilation duct 10. A defroster outlet 18, a heater outlet 20, and a vent outlet 22 are provided at the other end of the ventilation duct 10. The heater outlet 20 is provided with a first switching damper 24 for switching the open / closed state of the heater outlet 20.
The 18 and the vent outlet 22 are provided with a second switching damper 26 for switching the open / closed state. These switching dampers 24, 26 are driven by first and second switching damper driving actuators 21, 23. The evaporator 32 is for lowering the temperature of blown air during cooling, and is attached so as to be located over the entire cross section of the ventilation duct 10. This evaporator
Inside the ventilation duct 10 on the downstream side of 32, an air-mix type temperature control mechanism 34 is provided. The temperature control mechanism
34 is a heater core 36, which is a heat exchanger for heating provided in a part of the cross section in the ventilation duct 10 in the blowing direction, and a first air flow in which air flowing in the ventilation duct 10 flows through the heater core 36. And an air mix damper 38 that divides into a second air flow that bypasses the heater core 36,
It is composed of a drive actuator 39 for driving the air mix damper 38. Here, when the air mix damper 38 is fully opened (the solid line 38 in the figure
In the state shown by A), all the air flowing through the ventilation duct 10 passes through the heater core 36, so that the high temperature air that has passed through the heater core 36 is blown out from any of the outlets 18, 20, 22. On the contrary, when the air mix damper 38 is fully closed (the state shown by the chain line 38B in the figure), all the air flowing through the ventilation duct 10 bypasses the heater core 36 and flows, so that each air outlet 18 The air having the temperature that has passed through the evaporator 32 is blown out into the vehicle cabin as it is from any one of 20, 20, 22. Further, the air conditioner includes the drive motor 28 and each damper 2
A control circuit 40 is provided to control 4, 26, 38.
The control circuit 40 includes a temperature setter 46 for setting a set temperature and an outside air temperature sensor 4 for detecting an outside air temperature.
8, vehicle interior temperature sensor 50 for detecting the vehicle interior temperature,
Outputs from the solar radiation sensor 52 for detecting the amount of solar radiation and the glass surface temperature sensor 56 for detecting the temperature of the glass surface are input. Further, the control circuit 40 controls the drive motor 28
To output a control signal to a fan speed control device 29 for controlling the speed of the blower fan 30 and each drive actuator 21, 23, 39 for driving each damper 24, 26, 38. . The operation of the embodiment will be described below. When the air conditioner shown in FIG. 1 is operated in the vent mode, the second switching damper 26 opens the vent outlet 22 and closes the defroster outlet 18, and the first switching damper 24 operates as a heater. Open the outlet 20. Also, in the heater mode, the second switching damper 26 opens the defroster outlet 18 and closes the vent outlet 22, while the first switching damper 24 opens the heater outlet 20. As a result, the air flowing through the ventilation duct 10 is blown out from both the heater outlet 20 and the defroster outlet 18. In many cases, the defroster outlet 18 is the heater outlet 20.
Therefore, in the heater mode, most of the air flowing through the ventilation duct 10 blows out from the heater outlet 20 and a small amount from the defroster outlet 18. In the above heater mode, most of the air flowing through the ventilation duct 10 is used for heating the passenger. Further, in the defroster mode, the switching damper 26
Opens the defroster outlet and closes the vent outlet 22, and the first switching damper 24 closes the heater outlet 20.
Alternatively, the switching damper 24 may open a part of the heater outlet 20. In this case, most of the air flowing through the ventilation duct 10 is blown out from the defroster outlet 18 and a small amount is blown out from the heater outlet 20. Also, from the defroster outlet 18 toward the front window, from the vent outlet 22 mainly toward the upper body of the occupant, the heater outlet
From 20 onwards, air is blown mainly toward the feet of passengers. By the way, the control circuit 40 uses the set temperature t _s set by the temperature setter 46 and the outside temperature t detected by the outside temperature sensor 48.
and _o, and the vehicle interior temperature t _r of the passenger compartment temperature sensor 50 has been detected,
Based on the amount of solar radiation St detected by the solar radiation sensor 52, the vehicle interior temperature
Target outlet temperature t required to bring t _r to the set temperature t _se
AO is calculated by the following equation (1). _{t AO = K 1 · t se} -K 2 · to -K 3 · tr-K 4 · St + C ... (1) _{However, K 1, K 2, K} 3, K 4, C is a constant. And, usually, the blowout temperature of the air conditioner is the target blowout temperature.
The control circuit 40 controls the air mix damper 3 so that it becomes t _AO.
A drive command is issued to the drive actuator 39 of 8 to control the opening and closing of the air mix damper 38. As a result, the vehicle interior temperature
It is possible to maintain t _r at the set temperature t _se . Further, the control circuit 40 controls the blown air volume with the air volume characteristic as shown in FIG. 2 with respect to the target blown air temperature t _AO determined as described above. That is, when the heating load is large and the target outlet temperature t _AO is large and when the cooling load is large and the target outlet temperature t _AO is small, the air volume is large, and when the heating load and the cooling load are small and the target outlet temperature t _AO is an intermediate value. It is controlled to blow out a small amount of air. On the other hand, the front window is often frozen when starting the engine in winter. At that time, the air conditioner is in the defroster mode, that is, the second switching damper 26 opens the defroster outlet 18 and the first switching damper 24 closes the heater outlet 20 or partially opens the heater outlet 20. If the engine cooling water temperature t _w detected by the water temperature sensor 54 is equal to or lower than the predetermined value B, the air volume control is performed as follows. That is, first, the control circuit 40 quickly detects the outside air temperature t _o , the vehicle interior temperature t _r , the engine cooling water temperature t _w , and the glass surface temperature sensor 56 in order to quickly melt the freezing of the front window. was based on the glass surface temperature t _g, the increase rate of the glass surface temperature t _g is calculated by the following equation optimal defroster blowing rate W that maximizes (2). _{W = {K w · (t} w -t o) / (K g · t g -K o · t o -K r · t r)} m ... (2) _{However, K w, K g, K} o, K _r and m are constants. Here, the equation (2) is derived as follows. It should be noted that FIG. 3 shows an example of arrangement of the vehicle front window 60 and the air conditioner for the purpose of explaining the formula. In the figure, 8 indicates an engine. The temperature t _sx of the air blown out due to the defroster at any position x along the front windshield 60 (hereinafter referred to as the defroster jet) is given by the defroster blowout temperature t _i :
It is expressed by the following equation (3). (T _sx −t _r ) / (t _i −t _r ) = (x / D) ^kn (3) However, D and K _n are constants. Therefore, when x = l, the following equation (4) can be derived by using the equation (3). Therefore, based on this equation (4), the temperature t of the defroster jet at the position l along the front window 60 is t
_s is represented by the following equation (5). (T _s −t _r ) / (t _i −t _r ) = (l / D) ^kn ＝ K _s … (4) t _s ＝ K _s・ (t _i −t _r ) ＋ t _r … (5) where K _s is a constant. On the other hand, the defroster outlet temperature t _i is calculated by the following equation (6). t _i = K _i · W ^{−m 2} · (t _w −t _o ) + t _o (6) However, K _i and m ₂ are constants. Further, when the heat balance equation is calculated such that the difference between the amount of heat received by the glass surface and the amount of heat released at the position 1 along the front window 60 is used for increasing the temperature of the glass surface, the following equation (7) is obtained. _{M · (dt g / dt)} = K B · W m1 x (t s -t g) -K A · (t g -t o) ... (7) However, t is time, in t _g is the position l The glass surface temperature of the front window 60, dt _g / dt, is a time derivative of the glass surface temperature t _g . Further, M, K _B , K _A and m ₁ are constants. Here, substituting t _i in the above equation (6) into the equation (5) to eliminate t _i , and then substituting this t _s into the equation (7) gives the following equation (8). M · (dt _g / dt) = K _B · K _S · K _i · W ^m1-m2 · (t _w −t _o ) + K _B · K _S · W ^m1 · t _o + K _B × (1-K _s )・ W ^m1 · t _r −K _B · W ^m1 × t _g −K _A · (t _g −t _o ) ... (8) Here, the time differential dt _g / dt of the glass surface temperature t _g is the glass surface. The rate of increase of the temperature t _g , and if this is R, the defroster airflow W that maximizes the rate of increase R can be obtained from ∂R / ∂W = 0. Therefore, when ∂R / ∂W is obtained from the equation (8), the following equation (9) is obtained. (∂R / ∂W) = (1 / M) ・ {K _B・ K _s・ K _i × (m ₁ −m ₂ ) ・ W ^m1-m2-1・ (t _w −t _o ) ＋ K _B・ K _s・ m ₁・ W ^m1-1・ t _o + K _B × (1-K _s ) ・ m ₁・ W ^m1-1・ t _r −K _B・ m ₁・ W ^m1-1・ t _g −K _B × W ^m1 · (∂t _g / ∂W) -K _A × (∂t _g / ∂W)}… (9) When there is a certain defroster air flow rate W, the rate of rise of the glass surface temperature R
When the air flow rate becomes maximum, the glass surface temperature t _g also becomes maximum when the air flow rate is W, and ∂t _g / ∂W = 0. Therefore, if ∂R / ∂W = 0 and ∂t _g / ∂W = 0 in equation (9), the following equation (10)
Is required. _{^{W -m2 = {(K B ·}} m 1 · t g -K B × (1-K s) · m 1 · t r -K B · K S × m 1 · t o} / {K B · K S・ K _i × (m ₁ −m ₂ ) · (t _w −t _o )} (10) From this equation (10), the defroster air flow W that maximizes the rate of rise R is calculated by the following equation (11). W = [K _B · K _S · K _i · (m ₁ −m ₂ ) × (t _w −t _o ) / {K _B · m ₁ · t _g −K _B · (1-K _s )
・ M ₁ · t _r −K _B · K _S · m ₁ · t _o }] ^{1 / m 2} (11) The constants in the equation (11) are summarized as in the following equations (12) to (16). In a nutshell, it becomes the formula (2) shown above, and
It is understood that the formula (2) is a formula for obtaining the defroster blown air amount W that maximizes the increase rate R of the glass surface temperature t _g . K _B・ K _S・ K _i・ (m ₁ −m ₂ ) ＝ K _w … (12) K _B・ m ₁ ＝ K _g … （13） K _B・ (1-K _s ) ・ m ₁ ＝ K _o … (14) K _B · K _s · m ₁ = K _r … (15) (1 / m ₂ ) ＝ m… (16) In the defroster mode, the second switching damper 24
When the heater outlet 20 is closed and partially opened,
It suffices to slightly change the values of the constants K _w , K _g , K _o and K _{r in} the equation (2). As described above, the control circuit 40, which has calculated the defroster blown air amount W by the equation (2), then obtains the calculated defroster blown air amount W from the blower fan 30, as shown in FIG. From the relationship of the applied voltage, the applied voltage with respect to the required defroster air flow rate W is obtained. The relationship in the figure can be selected according to the characteristics of the drive motor 28 and the blower fan 30. Then, a signal for supplying the obtained applied voltage is output to the blower fan speed control device 29 to control the rotation speed of the drive motor 28 to obtain the defroster air volume W. Thereby, the rate of increase R of the glass surface temperature t _g of the front window 60 can be maximized and the freezing of the front window can be melted most quickly. The blower fan speed control device 29 may be configured by using a semiconductor, for example, a transistor, and in this case, the drive motor 28 performs pulse duty control. According to this duty control, the voltage applied to the drive motor 28 is changed by changing the duty ratio,
A desired air flow rate can be obtained. Then, the air conditioner controls the defroster air flow rate W in the defroster mode as described above, and after the engine cooling water temperature _tw has risen sufficiently, that is, becomes larger than the predetermined value B, returns to the normal air blow control, and the second air blow control is performed. Target outlet temperature t _AO shown in the figure
Blow out the air volume based on. This is because when the engine cooling water temperature t _w rises sufficiently, the air volume based on the equation (2) becomes very large, but in normal driving mode, the window is slightly fogged in the heater mode, and the defroster is required to clear the fog. This is because a large amount of air is not required when performing. Next, a control procedure of the air conditioner according to the present embodiment (mainly performed by a command from the control circuit 40) will be described based on a flow chart routine as shown in FIG. That is, when the routine shown in FIG.
, Read the set temperature t _se set by the temperature setter 46,
Step 120, outside air temperature sensor 48, vehicle interior temperature sensor 5
0, solar sensor 52, water temperature sensor 54, glass surface temperature sensor 5
Read each input value from 6. Next, at step 130, the target outlet temperature t _AO is calculated based on the above equation (1). Next, at step 140, it is judged if the control mode of the air conditioner is the defroster mode. If the determination result is negative, that is, if it is not the defroster mode, the process proceeds to step 150, and control other than the defroster mode is performed. Since the control in this step 150 is a normal control, detailed description is omitted. On the other hand, when the determination result is positive, that is, when it is determined that the defroster mode is set, the routine proceeds to step 160, where it is determined whether the engine cooling water temperature t _w is the predetermined value A or lower. If the determination result is positive, the process proceeds to step 170, and the blower fan 30 is stopped. Thus, the blower fan 30 is stopped when the engine cooling water temperature t _w is low such that the blowout temperature of the ventilation duct becomes 0 ° C. or lower. On the other hand, if the determination result is negative, that is, if the engine cooling water temperature t _w exceeds the predetermined value A, the routine proceeds to step 180, where it is determined whether the engine cooling water temperature t _w is lower than the predetermined value B or not. The predetermined value B is larger than the predetermined value A. When the determination result is negative, that is, when the engine cooling water temperature t _w is higher than the predetermined value B, it is determined that the engine cooling water temperature t _w has sufficiently risen, and therefore the routine proceeds to step 190.
The air volume based on the target outlet temperature t _AO is calculated based on FIG. Then, in step 200, the voltage to be applied to the drive motor 28 is obtained in order to blow out the calculated air volume. Then, in step 210, the obtained applied voltage is instructed to the blower fan controller 29 to apply the voltage to the drive motor 28. On the other hand, when the result of the determination in step 180 is positive, the engine cooling water temperature _tw is greater than the predetermined value A and is less than the predetermined value B, and the engine cooling water temperature _Tw is given a sufficient temperature for the air to be blown. Since it is determined that the temperature has been reached, the process proceeds to step 220, and the optimum defroster air volume W is calculated based on the equation (2). Then, in step 230, the voltage to be applied to the drive motor 28 is obtained from the obtained optimum defroster air flow rate using the relationship shown in FIG. Then step
At 240, a command is sent to the blower fan control device 29 to apply the obtained voltage to the drive motor 28. After the steps 150, 170, 210, and 240 are completed as described above, this routine is once ended, and then the process returns to the start again and this routine is executed. Thereafter, this procedure is repeated. In the above embodiment, depending on the case where the air conditioner according to the present invention is controlled based on the flow chart routine shown in FIG. 5, the routine for controlling the air conditioner is shown in the figure. It is not limited to. In that case, when the drive motor 28 was controlled to control the rotation speed of the blower fan 30, the applied voltage to the drive motor 28 was duty controlled, but the drive motor is controlled by the voltage.
Alternatively, the motor is not limited to the one controlled by the duty ratio control, and an electric motor whose rotation speed is controlled by another well-known control method to obtain a desired air volume can be used. or,
The glass surface onto which the defroster jet is blown in the defroster mode is not limited to the front windshield, and it can be blown to another side windshield or rear windshield to secure a sideward or rearward view. Further, in the above embodiment, the case where the present invention is applied to the vehicle air conditioner configured as shown in FIG. 1 is illustrated, but the air conditioner for implementing the present invention has the structure shown in FIG. It is obvious that the present invention can be implemented in other air conditioners without limitation, for example, air conditioners not equipped with an evaporator.

[Effect of device]

As described above, according to the present invention, the fan air flow rate is controlled so as to maximize the temperature rise rate of the glass surface of a predetermined window at the time of engine start, and the maximum defroster effect is obtained to quickly freeze the glass surface. The excellent effect of being able to melt is obtained.

[Brief description of drawings]

FIG. 1 is a sectional view showing the overall construction of an embodiment of a vehicle air conditioner according to the present invention, including a partial block diagram, and FIG. 2 is a normal operation for explaining the operation of the embodiment. A diagram showing an example of the relationship of the air flow rate with respect to the target blowout temperature at the time, FIG. 3 is a sectional view of the essential part including a partial block diagram showing the temperature of each part of the glass surface of the front window and the state of the defroster jet, Similarly, FIG. 4 is a diagram showing an example of the relationship of the applied voltage to the drive motor with respect to the air flow rate, FIG.
The figure is also a flow chart showing an example of a flow chart for determining the air volume. 8 ... Engine, 10 ... Ventilation duct, 12 ... Outside air intake, 14
… Inside air intake, 16… Inside and outside air damper, 18… Defroster outlet, 21… First switching damper drive actuator, 23
... second switching damper drive actuator, 24 ... first switching damper, 26 ... second switching damper, 28 ... drive motor, 29 ... fan speed control device, 30 ... blower fan, 34 ... temperature adjusting mechanism, 40 ... Control circuit, 46 ... Temperature setting device, 48 ... Outside air temperature sensor, 50 ... Vehicle interior temperature sensor, 52 ... Solar radiation sensor,
54 ... Water temperature sensor, 56 ... Glass surface temperature sensor, 60 ... Front window.

Claims (1)

[Scope of utility model registration request] 1. A ventilation duct having a plurality of outlets including a defroster outlet for blowing air toward a glass surface of a predetermined window and an air intake, and a damper for opening and closing the defroster outlet. a blower fan for flowing air to the ventilation duct, and the drive motor for rotating the air blowing fan, a heating heat exchanger for heating the air flowing through the air duct, detecting the outside air temperature t _o an outside air temperature sensor for a vehicle interior temperature sensor for detecting the vehicle interior temperature t _r, the air conditioning system and the water temperature sensor, is provided for detecting an engine coolant temperature t _w, said a glass surface temperature sensor for detecting the glass surface temperature t _g, shall apply in the defroster mode in which the defroster outlet is opened, the detected engine coolant temperature t _w is less than a predetermined value When the outside air temperature detected by the sensors t _o, vehicle interior temperature t _r, depending on the engine coolant temperature t _w and the glass surface temperature t _g, the temperature t of the defroster jets at position l along the glass surface of the window _{s, the} glass surface temperature t _g, and the outside air temperature t _o Based on the calculation considering heat balance, the target air flow rate W at which the rate of increase of the glass surface temperature t _g is maximum is calculated, and the air flow is calculated. A vehicle air conditioner, comprising: a control circuit that controls the rotational speed of the drive motor so that the air flowing through the duct reaches the calculated target air flow rate W.