JPS60259518A - Automatic air conditioner for automobile - Google Patents

Abstract

PURPOSE:To invariably obtain an adequate ventilation state by also introducing the air outside a car room automatically when only the air inside the car room has been introduced for a predetermined time in an air conditioner having a control mechanism controlling the ratio to introduce the air from the inside and outside of the car room. CONSTITUTION:The said device drives and controls a heat exchanger 190 in a heat exchange unit 1 via a control unit 2 based on the deviation between the preset target temperature set by an operation unit 3 and the car room temperature. When the car room heat load 490 is large, only the air inside the car room is introduced, and when the heat load becomes a predetermined value or less, the air outside the car room is also introduced automatically for ventilation. In this case, when the heat load is the said predetermined value or more, only the air inside the car room is introduced, and if this state is continued for a predetermined time or longer, the device automatically controls to also introduce the air outside the car room even though the heat load is the predetermined value or more, thereby an adequate ventilation state is obtained.

Description

[Detailed description of the invention]

[Field of Application of the Invention] The present invention relates to automatic air conditioners for automobiles, and in particular, to automatic air conditioners for automobiles suitable for application to those having an adjustment mechanism for adjusting the proportion of air introduced from the outside into the passenger compartment. This invention relates to air conditioners. [Background of the Invention] An adjustment mechanism for adjusting the proportion of air introduced from the outside into the interior of the vehicle of this type of automatic air conditioner for automobiles is disclosed in, for example, Japanese Patent Laid-Open No. 57-37935. That is,
Air is introduced into the vehicle interior, inside and outside the vehicle interior, and air from outside the vehicle interior in accordance with the state of the heat load in the vehicle interior (control signal [X]). For example, when the outside air temperature is high and the heat load on the vehicle interior is large, in order to ensure maximum cooling power, only air from within the vehicle interior continues to be introduced, and the above state may be fixed. Therefore, there were problems such as polluting the air inside the vehicle and impairing the health of the passengers. [Object of the Invention] An object of the present invention is to provide an automatic air conditioner for an automobile that enables ventilation of the vehicle interior regardless of the magnitude of the heat load in the vehicle interior and does not impair the temperature control of the vehicle interior. . [Summary of the Invention] The present invention is designed to automatically introduce air from outside the vehicle when only air inside the vehicle is introduced for a predetermined period of time.
The purpose is to regularly ventilate the passenger compartment. 1 1゛ [Embodiment of the Invention] An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an explanation of the principle of automatic temperature control employed in the embodiment shown in FIG. 2 according to the present invention. The target set temperature (Tsl) set on the operation unit 3 and the vehicle interior temperature (
TR: Compare the temperature difference ΔT=Ts TR with P
I calculate. If the result of the PI operation is set as X, the following equation holds true. (x) = k t (ΔT] 1/2f [ΔT] dt
The PI calculation unit 290 is a method generally used in the field of automatic control.As shown in the above equation, the PI calculation unit 290 sums up the proportional part of the difference between the target and the actual state of the controlled object and the temporal accumulation, and sets the controlled object to the target. Measure the amount required to transition to the state. The control section 3 drives the heat exchanger 190 in the heat exchange section 1 so as to send an amount of heat Q proportional to the value of the calculation result X into the passenger compartment 2. The air inside the vehicle (heat load 490) has the above heat amount Q and disturbance heat Qo.
receive. The disturbance heat Qo includes heat entering from outside the vehicle, radiant heat due to sunlight, heat transferred from the engine compartment, heat generated by the occupants, and the like. The air inside the vehicle receives a Q+QDO fever, and the temperature ('I'll) changes with a -th lag. )This(Tm'
) is negatively fed back to the control section 3. In such a negative feedback control system, if the coefficients of each element are appropriate, [Ta) becomes stable [T
8] is mathematically proven, automatic temperature control is achieved. Continuing on, the configuration of this embodiment will be explained using FIG. 2A, FIG. 2B, and FIG. 2C. Figure 2A. By combining in the order of FIGS. 2B and 2C, an air conditioner for an automobile corresponding to FIG. Connected to parts with the same number. The heat exchange section 1 is provided with an outside air suction port 101 for sucking air from outside the vehicle interior, an inside air suction port 102 for sucking air inside the vehicle interior, and a suction port door 111 for controlling the opening and closing of these suction ports. This suction door 111 is equipped with a two-stage action negative pressure actuator 112 and a return spring 113.
It is controlled to the 3rd position. That is, each negative pressure working chamber of this negative pressure actuator 112 is connected to a negative pressure source such as a negative pressure pump 90 (not shown) via solenoid valves 114 and 115, and the suction port door 111 is connected to a negative pressure source such as a negative pressure pump 90 (not shown). Valve 114.11
5 When both of the solenoid valves 114 and 115 are not energized, the inside air intake port 102 is closed by the force of the return spring 113, and the outside air is sucked in. When both the solenoid valves 114 and 115 are energized, both negative pressure operating chambers of the negative pressure actuator 112 are The external air suction port 1 (l) is closed by the supplied negative pressure, and the internal air is sucked in. Also, when the solenoid valve 114 is energized and the solenoid valve 115 is not energized, the negative pressure on one side of the negative pressure actuator 112 is Since negative pressure acts only on the working chamber, the suction port door 11
1 is stopped at an intermediate position in the above-mentioned state, and both the outside air suction port 101 and the inside air suction port 102 are opened to take in inside and outside air. The heat exchanger unit case 100 is provided with blowers 12, 1 that suck air from the suction port and send it to the heat exchanger, which will be described later. The air volume by the blower 121 is controlled by the driver 123 which is controlled by the controller 2.
2 by controlling the applied voltage supplied to 2. An evaporator 131 is provided downstream of the blower 121, and this evaporator 113i is connected to a compressor 132 and an expansion valve 13.
3 constitutes a compression refrigeration cycle, and serves as a cooling means for the air passing through it. The compressor 132 is driven by the automobile engine via a magnetic latch 132a, and the electromagnetic clutch 132a is energized or de-energized by a compressor relay 132b whose driving or non-driving is controlled by a control signal from the control section 2. It is done by doing. Furthermore, a heater core 141 serving as a heating means is provided downstream of the evaporator 131, and automobile engine cooling water (warm water) is circulated through the heater core 141.
1 heats the air passing through it. A temperature control door 142 is provided to control the amount of heating by increasing or decreasing the amount of air passing through the heater core 141. This temperature control door 142 is connected to the negative pressure source 90 via solenoid valves 145 and 146.
It is rotated by a negative pressure actuator 143 and a return spring 144 connected to. Solenoid valve 145°, 14
6. When both are energized, the negative pressure actuator 143
The negative pressure working chamber is connected to the atmosphere through the solenoid valves 145 and 146, so no negative pressure acts on it, and the return spring 144
The temperature control door 142 rotates in the direction in which θ decreases in FIG. 2, in other words, the amount of air passing through the heater core 141 increases. When the solenoid valve 145 is energized and the solenoid valve 146 is not energized, the negative pressure working chamber of the negative pressure actuator 141 is connected to the negative pressure source via the solenoid valve 146 and 145, and a negative pressure acts thereon. As a result, the temperature control door 142 rotates in the direction in which θ increases against the return spring 144. That is, it operates to reduce the amount of air passing through the heater core 141. A potentiometer 147 that operates in conjunction with the temperature control door 142 inputs a position signal corresponding to the position of the temperature control door 144 in the form of voltage VT to 148 of the control unit 2, and VT increases as θ increases. With the above configuration, the temperature control door 142 is feedback-controlled, and the amount of air passing through the heater core 141 is controlled by the blower 121.
Knee from 0 (θ is maximum) to 100% (θ is O) of air volume A. Eh, 8-2o a, 4□71ke91 air is,
The bypass 103 provided in parallel with the heater core 141 is energized, and the air passes through the heater core 141, mixes with the heated air, and is blown out into the interior of the vehicle. The air that has passed through the evaporator 131 and the heater core 141 or the bypass 103 enters the vehicle interior through the upper outlet 104 and the lower outlet 1.
05 or into the interior of the vehicle from the air outlet 106 to the windshield. A mode door 151 is provided for switching the air outlet into the vehicle interior, and like the intake door 111, this mode door 151 is also controlled to the third position by a two-stage action negative pressure actuator 152. The two negative pressure working chambers of the negative pressure actuator 152 each have a solenoid valve 154°1.
55 to the negative pressure source 90, and when both the solenoid valves 154 and 155 are not energized, the return spring 153 closes the upper outlet 104 and the air is discharged from the lower outlet 105. It's blown out. Further, when both the solenoid valves 154 and 155 are energized, the negative pressure source 90 is connected to both negative pressure working chambers of the negative pressure actuator 152, the mode door 151 closes the lower outlet 105, and the air is transferred to the upper outlet. It is blown out from 104. When the solenoid valve 154 is energized and the solenoid valve 155 is not energized, only one negative pressure working chamber of the negative pressure actuator 152 is connected to the negative pressure source 90.
Since the mode door 151 is connected to the above state, the mode door 151 is in an intermediate position between the above states, and both the upper air outlet 104 and the lower air outlet 105 are open, and the air is blown out from both secondary outlets, which is a so-called pie level state. The air outlet 106 to the front windshield glass is opened and closed by a door 156. Even when the door 156 is closed, it is normally configured so that there is usually a small amount of discharged air. The door 156 is connected to a negative pressure actuator 157 connected to the negative pressure source via a solenoid valve 15'9 and a return spring 1.
58. When the solenoid valve 159 is energized, negative pressure acts on the negative pressure actuator 157 and the differential door 1
56 opens against a return spring 158, and when the electromagnetic valve 159 is not energized, the door 156 is closed by the return spring 158. Immediately downstream of the evaporator 131, a thermistor-based discharge temperature sensor 160 is provided to detect the temperature of the air immediately after passing through the evaporator 131, that is, the discharge temperature Tc.
c is input to 161 of the control unit 2 in the form of voltage VcO. A cabin temperature sensor 170 is attached to an appropriate position in the cabin and inputs the cabin temperature Ti to 171 of the control unit 2. The control unit 2 includes an A/D converter 21 that converts analog signals from the sensors and the operating unit 3 into digital signals, and a microcomputer that processes the digital signals from the A/D converter 21 and the operating unit 3. 22, and an interface circuit 23 that controls each device of the heat exchange section 1 based on the output signals of the microcomputer 22. This interface circuit 23 connects the solenoid valves 114, 115, 145, 146° 15 of the heat exchanger 1.
4.155,159, transistor 231 as a switch element that controls compressor relay 132b
238, driver 12 supplying power to motor 122;
A D/A converter 23 for supplying an analog voltage l' to 23. It is composed of a lot of things. The operation unit 3 includes an air conditioner switch (not shown) for starting and stopping the device, a temperature setting device 31 for setting the desired temperature in the vehicle interior, a dehumidification switch 32 for manually dehumidifying the interior of the vehicle, and a blower. It is comprised of a switch 33 and the like for blowing air out from the outlet 106 onto the windshield. Desired temperature of the passenger compartment set by the above temperature setting device (
The target set temperature Ts) is input to the control unit 2 as a voltage Va, and the operation signal Vox of the dehumidification switch 32 and switch 33
u and Your are also input to the control unit 2 in the form of voltage. The operation of the automatic air conditioner according to the present embodiment having the above configuration will be explained. 3A and 3B are operation flowcharts of the microcomputer program of the control section 2. FIG. The numbers in the figure are step numbers indicating the order of the flow. As shown in the figure, the operation of this device includes the initialization step of steps 201 to 203, a main routine that returns an infinite number of lines in steps 204 to 217, and one cycle of the main routine (approximately 1 second in one example) during the processing of this main routine. Steps 220 to 2 are performed at a period several hundredths of a second (in the embodiment, one hundredth of a second).
and an interrupt routine that processes 27. First, when this device is activated by the air conditioner switch, the I10 data of the control unit 20 and microcomputer 22 is set to the initial value determined in step 201.
At step 202, a RAM (not shown) in the microcomputer 22 is cleared. Next, step 20
3, the voltage VT of the potentiometer 147 corresponding to the position (θ=0) of the temperature control door 142 is
Depending on the digital quantity [■! ] and read as the initial value of the door reference position. Note that this door reference position signal is monitored and updated in step 2''24 and in the aforementioned interrupt routine. Next, the main routine will be explained. In step 204, the voltage Vs, the voltage Vn corresponding to the vehicle interior temperature Ti, and the voltage Vc corresponding to the m discharged air temperature Tc are converted into digital values CVg) by the A/D converter 21.
(Vm:l, (Va)K is converted and input to the microcomputer 22. The voltage VT corresponding to the position of the temperature control door 142 is read by a timer interrupt as described later. [:Vi+3°(V
c) In step 205, the microcomputer 2
The conversion map circuit 240 stored in the ROM 2 converts digital values [Ti], (T
c) is converted to [v8] is the target setting temperature circuit 2 in step 206.
41, it is converted into a digital value [T8] of the target set temperature using a first-order conversion formula. In step 207,
The deviation [ΔT] between the target set temperature [T8] and the vehicle interior temperature [TII] is determined as [ΔT]=[:Ta:]−[TII]. Next, in step 208, the integral addition circuit 242 calculates the PI of IIx:l=k[ΔT:]+−f[ΔT)di.
An operation is performed. First, the integral term in the above equation is calculated by adding the temperature deviation [ΔT] every predetermined time specified by the timer process in step 226 of the interrupt routine, and then adding k(ΔT) to this integral term. The control signal [x] is detected (step 209). Note that in the above equation, τ is a constant determined by the control system. The control signal (x) determined in this way indicates that in the process of controlling the vehicle interior temperature TR to the target set temperature for one day, the vehicle interior heat load increases by an amount commensurate with the required amount of heat, and in this embodiment, k>0. ．． τ〉
Since (x) is chosen as
The larger the value, the greater the cooling power required for the cabin heat load. The operation of this air conditioner based on the value of this control signal (x) will be explained with reference to FIG. Figure 4 shows the horizontal axis control signal Ex
) shows the operating state of the heat exchange section 1. In step 210, the temperature control door target voltage (Vyo:l) for the control signal [x] is calculated and calculated. This target voltage (VTO) is calculated using the linear equation regarding (x) in the range x3≧X≧0 64), (x:l is

When [0], [VTo': l = CVTI], and when the predetermined positive value of (x) [x3], CVTO) = (V
TO). Here, (VTI) is the voltage of the potentiometer 147 when the temperature control door 142 closes the passage to the heater core 141 (θ is maximum), and (VTz] is the voltage when the passage to the heater core 141 is completely opened. (θ=0
) is the voltage of the potentiometer 147. Now, in step 222 of the interrupt processing routine, the voltage V of the potentiometer 147 is determined as the position signal of the temperature control door 142! is read in and converted into a digital value [v] by the A/D converter 21. Note that in step 220, the next timer interrupt is first allowed. Furthermore, in step 221, the contents of the registers used in the main routine are temporarily saved to another memory,
In the final step, the contents are returned to the register (step 227) so that the execution of the main routine will not be hindered. Next, in step 223, the temperature control door position control circuit 24
4, the position of the temperature control door 142 is controlled by comparing the target voltage (Vyo) and [Vyo]. Therefore, calculate the value of [ΔVte) = [Vto) - [Vt'), and calculate [ΔVT]≧ with respect to the predetermined value [JVtp)〉0]
The control signal [Tl] becomes "0" when [ΔVTp)chi1'', [ΔVT)<CΔ■τP], and [-ΔVIP]
A control signal [T2] which is 1'' when ≦[ΔVt]≦(JVtp) and is `0'' in other ranges is generated by the control signal generating circuit 245246, respectively. When the control signals [T1] and [T2] are "1#", the switching elements 233 and 234 are turned on, and the solenoid valves 145 and 146 are turned on.
is energized, and is not energized when it is '0#. Due to the above-mentioned operation, the temperature control door 142 is rotated in the direction of increasing θ in the figure due to the above-mentioned energization [ΔVd]>[Δ■τP], and [ΔVy
] < (-JV), the temperature control door 142 is rotated in the direction in which θ decreases. [-1 τP] ≦ [ΔVr) ≦ [JVtp)
Δ,,)−(ΔVTP)≦(Vyl)≦(VTII:]
+[ΔVTP), the temperature control door 142 is in a stationary state, and at this time the temperature control door position θ is equal to the target voltage (VTOI).
It is in a position corresponding to . Returning to step 214 of the main routine, the exhaled air temperature Tc
The target temperature (Tco) is requested by the exhalation target temperature setting circuit 247 as follows. [x] for a predetermined negative value of (x) [X@]
≦[x2], [Tco] becomes the lowest possible value [Tct') (2.5C in this example) where the evaporator surface is just before freezing, and in the range of (x)≧[x2], (x)= [xz]
and the above (T(41), [X]=

[0] is the predetermined value [Tcx
) (25C in this embodiment) is a value determined by a linear equation connecting two points. Note that the vicinity of Ex)=[:0] is a region where the cabin heat load does not require heating power or cooling power, and the outside air temperature To is close to the target setting temperature T8. In this region, there is almost no need to operate the cooling means [Tco) Ki (Ts]
is set. In the next step 215, the target discharge temperature (Tco) and the discharge temperature (Tc) are compared, and the temperature difference [ΔTa]
=CTco) (Tc) is calculated, and this [ΔTc)
Depending on the value of , the following compressor operation signal (C) is generated from the compressor operation signal generation circuit 248. That is, [ΔTc]≧

At [0], (C) is “0”, [ΔT
c)<Co), and (C) becomes '1''. When the compressor control signal (C) is 1'', the switching element 235 is turned on at step 217, energizing the compressor relay 132b. The magnetic clutch 132a is excited by the compressor relay 132b, the compressor 132 is operated, the air passing through the evaporator 131 is cooled, and the discharge temperature Tc is lowered. Exhaled air temperature Tc
If ΔTc decreases, eventually [ΔTc)≧

[0] becomes [C] =
It becomes ``'0''. Therefore, at the final step 217 of the routine, compressor 132 is deactivated. By repeating the operation and non-operation of the compressor 32 in this manner, the discharge air temperature Tc is maintained close to the target temperature (Tco) determined by the control signal [x]. However, as described above, in the range (x)≧0, the cabin heat 11 load requires heating power, so that the target set temperature Ts>the cabin outside air temperature To, and Tco>'TcmkiTm. Since the suction door 111 sucks air outside the vehicle interior, the temperature of the air sent to the evaporator 131 is close to the outside air temperature To. Therefore, even if the cooling means does not operate [ΔTc:]>
0, and the compressor 132 does not operate. And it becomes [Tc] ki c'ro]. The amount of air sent from the blower 121 to the evaporator 131, heater core 141 or bypass 103, that is, the blower
The air volume A is approximately proportional to the voltage VF supplied to the motor 122. The voltage supplied to this motor 122 is subjected to the following energization control. First, in step 216, a target voltage [Vr] is determined by the blower air volume calculation circuit 249 in response to the control signal [X]. Predetermined 1 piece [x
] for negative value [xl] and positive value [X4], [x]≦
[xt) and [x]≧[X4], the maximum value [Vr
t] (12v in this embodiment), and the negative value [X2
] Control is performed so that it becomes 0'3° (i!tl゛it''"rz) (1"*MfJr+'' 14V) until it reaches a positive value [X3]. In the range [xl]≦[x]≦[X2], when (xt:], then [:VF1.I+[X2], then l:Vyz:], by a linear equation connecting two points,
y). In the range of [X3]≦[x]≦[X4], [IVF2':l when [X3]. [Vr':l is determined by a linear equation connecting two points that become (VFI) when [X4]. In step 217, the obtained target value (Vr) is converted into an analog voltage VFI by the D/A converter 239, and the driver 1 is controlled by this voltage Vrs.
23 drives the shimotor 122. Therefore, when the control signal [X] is below (xt), the blower air volume A becomes the maximum Aa, 8, and [X1] and [X2]
The blower air volume is maximum Ama! From [X2] to [X3], the blower air volume was kept at the minimum Am between CX3) and [x4].
] The blower air volume varies from the minimum Again to the maximum □
The blower air volume increases linearly up to [x4] or more, and is continuously controlled so that the blower air volume reaches the maximum of [x4]. In addition to the above operations, in the middle of the main routine, the suction port door 11
1. The mode door 151 is also controlled by the value of the control signal [X] as described below. In controlling the suction port door 111, step 211 is performed.
x〕≦

[0] is 11”, (x]≧

[0] in 10#teshi1
control signal [It:), with (x)≦(xs)”
Control signal [X2] that becomes @0# when 1” [x]≧[X5]
is generated by the suction door control circuit 250. Here [x
s ] is a negative value and [Xl] < (xs ) < (xz ')
Chill with a certain value. When the control signals [11] and [Iz:] are "]1, in step 217 the 'switching element 231°23
2 is conductive and the solenoid valves 114 and 115 are energized, and when it is "0", the solenoid valves are not energized. When control signal [x]≦(xs:l, as described above, [
It ), (It ) both 1'' stain magnetic valve 114.1
15 are both energized, and the suction door 111 is actuated by the actuator 112.
Due to the operation of υ, the state a of internal air suction is achieved. (x〕≧

[0]
When , [Is). [2] Both are 0#, and the suction door 111 is pulled by the return spring 113 and enters the state of sucking outside air. [x5]≦[X]≦

When [0], [11] becomes “1#”
, [I2] are "0'", the suction door 111 is in the intermediate position, and enters the internal/external air suction state C. The basic operation of the suction port door 111 has been described above, and below, the operation of the suction port door 111 based on the present invention will be explained with reference to FIG. 6. FIG. 6 corresponds to FIG. 4 of the above-mentioned explanatory drawings, and only shows the parts that are different from FIG. 4. As mentioned above, when the control signal (x)≦[x5], the inside air suction state a is reached, but as shown in FIG. To,
The point at which the state C of internal and external air suction changes to the state A of internal air suction [x
-:] (However, a switching point is provided at [x8]<[x*'ll<0). Furthermore, from the time when the suction port door 111 enters the inside air suction state a, the inside air suction timer processing step 2 is started.
At step 26, a predetermined time defined by the inside air intake timer 243 is measured. And the internal air intake timer 243
When the predetermined time defined by (10 minutes in this embodiment) begins to elapse, if (xa 〕<(x)≦[x9] The above signal [It] turns Ia ON.[I2] is generated by the suction road control circuit [250].Then, in step 217, the switching element 231 is made conductive and the switching element 232 is made non-conductive, and the solenoid valve is turned on. 114 is energized and 115 is not energized.
becomes state C, where internal and external air is sucked. At that time, the internal air intake timer that measures the predetermined time is cleared (not shown). However, since the suction port door 111 enters the state C of sucking inside and outside air, the high-temperature, unloaded outside air enters the vehicle interior, and at least the control signal [xa] tends to increase toward the negative side. If the heat load is large and Ex)≦[x8], step 211 returns the control signal CIt :], [I
2 ] The above signals [It '11. (
Is] is generated by the suction load control circuit 25. Then, in step 217, the switching elements 231,
232 becomes conductive, energizing the solenoid valves 114 and 115. Then, the suction port door 111 enters the state a of inside air suction. Then, the state a of inside air suction as described above is measured, and if a predetermined time has elapsed and [xs)<[:x]≦[x9], then the state C of inside and outside air suction is returned. Thereafter, the above operation is repeated. Similarly, the mode door 151 is also controlled by the control signal Ex). The control of this mode door 115 is such that the value of Ex) is [
When x6] is also smaller, upper blowing is performed, when larger than [x7], lower blowing is performed, and in the zone between [x6] and [x7], both upper blowing and lower blowing are performed, and (0) < (xa ] < ( x)
'] < [x3] [xs ':], Ex7:
] is set. As an actual control signal, (x) < [x7], “1#, E
Control signal [01] which becomes 10# when x)≧[x7], and (
In step 212, the mode door control circuit 251 generates a control signal [02] which becomes 1'' when x:]<(xg) and 0# when [x]≧[x6]. Depending on the values of the control signals [Ot], [Oz], the mode door 151 is driven in step 217 as follows. [:xl) < [:xs:], then (Ox :], [(h
:) Both 1111# switch elements 236, 23
7 are turned on, both solenoid valves 154 and 15511 are energized, and the mode door 151 is brought into an upward blowing state by the actuator 152. In [xa] [x7], both [Ot:] and [Oz] are 0#, the solenoid valves 236 and 237 are not energized, and the mode door 151 is in the downward blowing state due to the return spring 153. If [x6]≦[x]≦Cx't, then [01] is "1"
", ((h) becomes '0', so the solenoid valve 154 is energized, and the solenoid valve 155 is not energized, so the mode door 151 is in the intermediate position and in the upper and lower blowing state. Figure 5 shows the amount of heat dissipation (Q) (which becomes negative in the cooling region where [x) is zero). , ) and the amount of heat [Qc] possessed by the air that passes through the evaporator 131 and then passes through the bypass 103.In order to make it easier to understand the basic characteristics, the cabin temperature [Ti] was maintained at the target set temperature [Ts]. Based on the state. The air temperature immediately after passing through the heater core 141 is [TH
], If the air volume passing through the heater core 141 in the blower air volume CADI is [AlI3, then [QR) - ([TH
) [Tn:l)[An)CQc)-((Tc:]
(TR)) ((A) [AII:l) In the region of [x]≧0, the above-mentioned 9 current cooling means does not operate and the heat exchanger 1 sucks the outside air of the passenger compartment, so the outside air temperature of the passenger compartment during Tc To
There is a relationship of ≦Ta x Ts. In the range [x3]≧[x]≧[0), [Q:l=I:
Qm]+(Qc':l"([Ta) [Till)[A
Ii:)+([To) (TR))(CAMlN) C
AR]). Assuming that the heating means has sufficient capacity ((
Ta ) l:TR]) is almost constant, heater core 14
The amount of air passing through 1 [Aa:l is O~(:AMI)! Since [Qa] increases linearly between 3 and 3, [Qa] increases linearly from 0 with respect to an increase in [x]. Also [x') = (0)
Nearby, (To)kiCTn], therefore, [Qc]ki0. [For x':l=[x3:], [AH) = [Am
tN], then [Qc')=O. And [x3
]≧X≧0, [To]≦(Tml, so [:Qc
:l≦0. In the range [x]≧[x3], [Ai )=I:A), and therefore [Q]4Qi)”(1:TH:]−
1: T trap)) [A), ([TII] - (TRY)
is constant and [A] changes linearly with respect to (x), so [q] increases linearly as (X) increases. In the range of [x]<(0), [AlI3-0] exists, and the ability of the cooling means is sufficiently reduced to reach the target discharge temperature [Tco] in the discharge temperature [Tc]. In the range [0)>(x]≧[x2], [Q]=(Qc
)” ((Tc) [Ti)) [AmxN], [A
ml*) constant. Ex) increases in the negative direction ), and (Tc Ti) increases from 0 to [Tcr) (Til
Since it changes linearly to l, (Q) is the cooling power [x
It increases linearly from 0 as l) increases in the negative direction. In the range of [x2]≧(x)≧[,Xt], [Tc]
Since [A) changes linearly with [x] at a negative constant value of CTi] = ([Tct:l (TR)), [X]
As Q increases in the negative direction, [Q) increases proportionally as the cooling power. As shown in FIG. 5, it has been confirmed that Q continuously and monotonically increases with respect to [x]. With the configuration and method described above, even if the outside air temperature is high, the heat load inside the vehicle is large, and the air intake door 111 is in state a of sucking inside air, the vehicle will automatically shut down after a predetermined period of time. The system enters state C in which air is sucked in from outside, and if the heat load is still large, it returns to state A in which air is sucked inside, which has the effect of making it possible to ventilate the passenger compartment without compromising the temperature control of the single room. . [Effects of the Invention] According to the present invention, the vehicle interior can be ventilated without impairing the temperature control of the vehicle interior, regardless of the magnitude of the heat load in the vehicle interior. Furthermore, there is an effect that the health of the occupants will not be impaired.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of the principle of automatic temperature control according to an embodiment of the present invention, Figs. 2A, 2B, and 2C are partial views, and their combination (simply referred to as Fig. 2) is An overall configuration diagram of an embodiment of the present invention, FIGS. 3A and 3B are flow charts of the microcomputer program of the control section shown in FIG. 2, and FIG. 4 is an explanation of the operation of the heat exchange section shown in FIG. 2. 5 is a characteristic diagram of the amount of heat radiated into the vehicle interior by the heat exchange section, and FIG. 6 is an explanatory diagram based on the present invention. 1... Heat exchange section, 2... Control section, 3... Operation section,
22... Microcomputer, 31... Temperature setting switch, 111... Suction port door, 121... Blower-1131... Evaporator, 133... Compressor, 141... Heater core, 142...・・Temperature control door, a
... Inside air intake state, b... Outside air intake state, C.
・Internal and external air intake status, 243 ・・・Inside air intake timer. Agent Patent Attorney Akio Takahashi No. 5

Claims (1)

[Claims] 1. When the heat load inside the vehicle is large, only the air inside the vehicle is introduced, and when the heat load becomes equal to or less than the first predetermined amount, the air outside the vehicle is automatically introduced. In the automatic air conditioner for automobiles, which has the function of introducing
If the state in which only the air inside the vehicle is introduced continues for more than the first predetermined amount of time, even if the heat load is more than the first predetermined amount, An automatic air conditioner for an automobile, characterized in that air from outside the vehicle is also introduced into the vehicle. 2. In claim 1, the heat load is
When the condition in which the amount of air outside the vehicle is also introduced by continuing for the first predetermined amount of time, if the condition continues for more than the second predetermined time, the air inside the vehicle is automatically introduced. An automatic air conditioner for an automobile, characterized in that the automatic air conditioner returns to a state where only air is introduced. 3. In claim 1, if the heat load increases to a second predetermined amount or more, which is larger than the first predetermined amount, when air from outside the vehicle is also introduced, the air inside the vehicle is automatically When the heat load is between the first and second predetermined amounts, the state in which only air is introduced into the vehicle interior is returned to the state for the first predetermined period. An automatic air conditioner for an automobile, characterized in that if the above continues, air from outside the vehicle is automatically introduced.