JPS60163717A - Air-conditioning system for automobile - Google Patents

Abstract

PURPOSE:To reduce substantially the consumption of unrequired power by controlling the duty of a compressor in response to a heat load during air cooling and controlling the duty of the compressor in response to an external temperature when dehumidification is required during heating. CONSTITUTION:An air-conditioning system is provided with a heat exchanging unit 1 in which air drawn from inside or outside of a car room is regulated in temperature in the course passing through an evaporator 131 and a heater core 141 and then it is blown into the room through blowing openings, and with a control unit 2 for controlling various controlling devices in the heat exchanging unit 1. The control unit 2 is supplied with a starting/stopping signal and a desired set temperature signal from an operating unit 3 and with device condition signals from sensors. The control unit 2 is adapted to control a compressor 132 of a refrigenrating cycle in response to a heat load during air cooling and to control the duty of the compressor 132 in response to an external temperature when dehumidification is required during heating. Thus, unrequired power consumption is substantially reduced.

Description

[Detailed description of the invention]

[Field of Application of the Invention] The present invention relates to an air conditioner for an automobile that cools and heats the interior of an automobile. [Background of the Invention] Fig. 1 is a schematic configuration diagram of an automobile nitrogen air conditioner fil (hereinafter referred to as an air conditioner), and shows a device related to the so-called reheat air mix method. According to the figure, The air introduced into the single room I or the outside of the vehicle is converted into an eno (borator 10) by a proa fan 103.
Air is blown to 1. Air mix door 104 (hereinafter referred to as A/M door)
The air that has been dehumidified and cooled by the evaporator 101 is divided into a flow path that passes through the heater core 102 and is heated again, and a flow path that bypasses the heater core 102 as it is. Here, by changing the position of the A/M door 104, the temperature of the air discharged from the air conditioner can be changed. However, in conventional temperature control using the heat-air mix method, even during heating when cooling is not required, the compressor
08, and when the cooling capacity was not so required, the A/M door 104 was opened to reduce the cooling capacity. All of these consume unnecessary power. For this reason, in recent years, there has been an increase in the number of air conditioners that separate cooling and heating. In particular, in automotive air conditioners (hereinafter referred to as auto air conditioners) that automatically control the interior temperature of the vehicle toward a target temperature, the compressor is forcibly turned off depending on the outside temperature, the amount of heat required, or the blowout temperature. there were. FIG. 2 shows how the compressor is controlled to be turned on or off when the outside air temperature reaches 15C. In addition, Fig. 3 shows that a temperature-sensitive element such as a thermistor is installed just before the evaporator, and the necessary blowing temperature to maintain the temperature in a single room at the set temperature is calculated using a calculation device such as a microcomputer, and the value and The compressor is controlled based on the difference ΔT from the suction temperature determined by the temperature sensing element. In the figure, when the temperature difference ΔT is 20C or more, the compressor is turned off, and when the temperature difference ΔT is 10C or less, the compressor is turned on. Furthermore, the control of a manual air conditioner, which controls the temperature by opening and closing the A/M door by moving the operating lever 9 of the operating panel 40 left and right as shown in FIG. 4(a), is as shown in FIG. 4(b). It's like that. In other words, this woodcutter's air conditioner is
As shown in No. 11, cooling and heating are completely separated, and the A/M door adjustment lever 9 and the variable thermostat that controls the temperature at which the A/M door and compressor are turned off are controlled in conjunction. In other words, on the heating side, the A/M door is gradually moved to the full hot position, and the compressor is accordingly turned off.
FF. On the cooling side, the off-temperature OFT, which turns the compressor off, is gradually lowered, and the A/M door is fixed at the full cool position. Furthermore, A/M calculates a value that determines the amount of heat released by the air conditioner based on the difference between the interior temperature of the vehicle and the set target temperature using a calculation device such as a microcomputer.
There are also automatic air conditioners that control door opening, compressor on/off control, and other door controls. However, in such an automatic air conditioner, the compressor is turned off during heating, so depending on the outside air conditions, the interior of the vehicle may become stale. [Object of the Invention] An object of the present invention is to provide an air conditioner for an automobile that does not cause abrasion of the window glass due to a sudden change in the difference between the outside temperature and the inside temperature of the vehicle even during heating. purpose. [Summary of the Invention] To achieve this object, according to the present invention. During the heating operation of the air conditioner, the operating capacity f of the compressor
For example, (1) υ that lowers the evaporator discharge temperature to around the off temperature that balances with the outside air, (2
) Turn on the compressor only up to a certain temperature, or
(3) On/off control of the compressor is performed at a constant duty ratio. [Embodiments of the Invention] The present invention will be described in detail below with reference to the accompanying drawings. Note that the same reference numerals in each figure indicate similar objects. FIG. 5 is a system diagram showing an automatic air conditioner according to an embodiment of the present invention. According to the figure, this air conditioner electrically controls the heat exchange section ↓ and each device in this heat exchange section ↓, which sucks in all air from outside and outside the vehicle, heats or cools it, and blows it out into a single room where the air is conditioned. A control section 2 for inputting the start/stop of this device and a desired set temperature to the control section 2, and a vehicle room temperature signal and a heat exchange section 1.
It consists of sensors that input equipment status signals to the control unit μ. The control unit 1 is equipped with an outside air intake loi for sucking air O from outside the vehicle interior, an inside air suction port 102 for sucking in a single indoor air vent, and an inlet 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 11.
3, the third position is controlled to 11°. That is, a negative pressure source -P such as a negative pressure pump is connected to the negative pressure source -P through the negative pressure working chambers l-1 and 'IIL magnetic valves 114 and 115 of this negative pressure actuator 112, respectively.
The inlet door 111 is connected to the solenoid valve 114.
, 115 are not energized, the force of the return spring 113 closes the inside air intake port 102 and maintains the outside air suction state. Furthermore, when both the electromagnetic valves 114 and 115 are energized, the negative pressure supplied to both negative pressure working chambers of the negative pressure actuator 112 closes the outside air suction port 101 and enters a state of sucking inside air. Furthermore, when the solenoid valve 114 is energized and the solenoid valve 115 is not energized, negative pressure acts only on one negative pressure working chamber of the negative pressure actuator 112, so the inlet door 111 stops at an intermediate position between the above states and outside air is turned off. Both the suction port 101 and the internal air suction port 102 are opened to suck in internal and external air. The heat exchanger unit case 100 is provided with a proar 121 that takes in all the air from the suction port and sends it to the heat exchanger described later. The air volume by the blower 121 is controlled by controlling the applied voltage supplied to the motor 122 by a driver circuit 123 controlled by the control unit 2. An evaporator 131 is provided downstream of the proar 121. This evaporator 131 is a compressor 132
A compression refrigeration cycle is constituted by an expansion valve 133 of a % condenser (not shown), and serves as a cooling means for the air passing through this cycle. The compressor 132 is driven by the automobile engine via an electromagnetic clutch 132a, and its driving and non-driving are performed by energizing and de-energizing the electromagnetic clutch 132a by a compressor relay 132b controlled by a control signal from the control unit 2. . A heater core 141 serving as a heating means is provided downstream of the evaporator 131, and the engine cooling water (warm water) of the automobile is applied to the heater core 141 to heat the air passing through the heater core 141. A temperature control door 142 is provided on the inlet side of the heater core 1410 to control the heating t by increasing or decreasing the amount of air passing through the core 141. This temperature control door 142 is rotated by a negative pressure actuator 143 and a return spring 144, which are connected to the negative pressure source via electromagnets 7P145 and 146. That is, when both the solenoid valves 145 and 146 are not energized, the negative pressure chamber of the negative pressure actuator 143 is communicated with the atmosphere through the solenoid valves 145 and 146, so that no negative pressure is applied, and the temperature is controlled by the return spring 144. door 14
2 rotates in the direction in which θ decreases in FIG. 5. In other words, the amount of air passing through the heater core 141 is increased. 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 -P via the solenoid valves 146 and 145, and a negative pressure acts thereon. As a result, the temperature control door 142 rotates in the direction in which 0 increases against the return spring 144. That is, an operating yometer 147 is provided in the direction of reducing the amount of air passing through the heater core 141, and inputs a position signal corresponding to the position of the temperature control door 144 to the control unit 2 in the form of a voltage VtO to adjust the angle of θ. As the voltage increases, Vt increases. Although the details will be described later, the temperature control door 142 is feedback-controlled with the above configuration, and the amount of air passing through the heater core 141 is
The flow rate C of the proar air sent by 21 is controlled from 0 (θ is maximum) to 100% (θ is 0). Air that does not pass through the heater core 141
The air passes through the bypass passage 199 provided in parallel to the air filter 1, completely passes through the heater core 141, mixes with the heated air, and is blown into the interior of the vehicle. Evaporator 131 and heater core 141 or bypass 1
The air that has passed through 99 is blown into the interior of the vehicle through the upper air outlet LOW UPP, the lower air outlet LOW, or the differential air outlet DEF to the windshield. A mode door 151 that switches all air outlets into a single room is provided, and this mode door 151 also has a two-stage action negative pressure actuator 152 similar to the inlet door 111.
It is controlled to 3 positions by The two negative pressure working chambers of the negative pressure actuator 152 are connected to the negative pressure source -P via electromagnetic valves 154 and 155, respectively, and when both the electromagnetic valves 154 and 155 are not energized, a return spring is activated. Upper outlet UP by 153
P is closed and the air is blown out from the lower outlet LOW. Further, when both the solenoid valves 154 and 155 are energized, a negative pressure source is supplied to both negative pressure working chambers of the negative pressure actuator 152.
P is connected and the mode door 151 is in the lower outlet LOW
is closed, and the air is blown out from the upper outlet UPP. 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, so the mode door 151 is in the intermediate position, upper position, in the above state. Both the air outlet UPP and the lower air outlet LOW are in an open state, and the air is blown out from both secondary outlets. This is a so-called pi-level state. The differential air outlet DEF is opened and closed by the differential door 156 (
Even when the differential door is closed, there is usually a small amount of discharged air). The differential door 156 is connected to a negative pressure actuator 157 connected to the negative pressure source via a solenoid valve 159 and a return curtain 1.
58. When the solenoid valve 159 is energized, the negative pressure actuator 1
57, the differential door 156 opens against the return spring 158, and when the electromagnetic valve 159 is not energized, the dead 7156 is closed by the return spring 15B. Immediately downstream of the evaporator 131, a discharge temperature sensor 160 is provided, such as a thermistor, for detecting the temperature of the air immediately after passing through the evaporator 131, that is, the discharge temperature Tc.
The exhaust air temperature Ta is input to the control section 2 in the form of a voltage Vc. A vehicle room temperature sensor 170 is attached to a suitable position in the single room and manually inputs the vehicle interior temperature T8 to the control unit 2 in the form of a voltage 8. The control section includes a digital converter 21 that converts the analog signals V, Va, and Vck from the sensors and the operating section 3 into digital signals, and a microcomputer that processes the digital signals from the AD converter 21 and the operating section 3. 22, and an interface circuit 23 which controls each device of the heat exchange section 1 using output signals from the microcomputer 22. This interface circuit 23 connects the solenoid valves 114, 115, .
145, 146, 154, 155, 159, a switching circuit 24 comprising a transistor as a switching element for controlling the compressor relay 132b't, and a driver circuit 12 for supplying power to the motor 122;
D/A converter 2 that supplies analog voltage to 3.
Consists of 5. The operation unit 3 includes an air conditioner switch for starting and stopping this device, and a temperature setting device 31 for setting the desired temperature inside the vehicle. It is composed of a differential switch 33 and the like for blowing air out from the differential outlet DEF to the windshield. The desired temperature of the single room (target set temperature Ts) set by the temperature setting device 31 is inputted to the control unit 2 as a voltage Vs,
Further, the operation signal V o *y of the differential switch 33 is also input to the control unit 2 in the form of a voltage level. Next, the operation of this embodiment will be explained. 6 and 7 are flowcharts of the operation of the control section 2. FIG. The numbers in parentheses in the figure are step numbers indicating the order of the flow. The illustrated energization and operation of the device are performed in step [20
1) - (203) initialization, step (204)
) to (217) an infinite number of times, and during the processing of this main routine, the cycle is several hundredths of the cycle (for example, about 1 second) of the main routine (for example, about 1 second).
It consists of an interrupt routine that processes steps (2201 to (227)) in 1/00th of a second). First, when the device is activated by the air conditioner switch, the I10 data of the microcomputer 22 of the control section 2 is determined. It is set to the initial value (2011, and the RAM of the microcomputer 22 is cleared (202). Next, the voltage "Ir" of the potentiometer 147 corresponding to the @key door 1420 position (θ=OJ) is set to the AD converter 21.
It is converted into a digital value and read as the initial value of the door reference position. Note that this door reference position signal is monitored and updated by the interrupt routine (224).
. Regarding the standard position setting and updating of the temperature control door, please refer to the patent application filed in 1973.
5-159523 for details. Third, the main routine will be explained. A voltage Vs corresponding to the target set temperature Ts set by the operation unit 3, a voltage VR corresponding to the vehicle interior temperature TII, and a voltage VC2 corresponding to the discharge air temperature Tc.
The digital values [vs ], CVi+ ], [
'Vc)K conversion The reading of the voltage vt corresponding to the position of the temperature control door 142, which is input to the microcomputer 22 (204), is performed by a timer interrupt and will be described later. C
'Vn]. (vc) t; t, the conversion map stored in the ROM of the microcomputer 22 converts it into a digital value CTi+ ), (Tc ) corresponding to the cabin temperature and exhaust air temperature (p).
05). [v8] is converted to the digital value of the target set temperature [T8] according to the first-order conversion formula (2061° Deviation between the above target set temperature [T8] and the vehicle interior temperature (Tm) [:JT: ]
=[:Ts] [Tn] is set (2071° Fourth, (X:l=k[ΔTE+−fCΔ'l']dt
A PI calculation is performed. First, the integral term in the above equation is determined by adding the temperature deviation [ΔT] every predetermined time specified by the timer process (226) of the interrupt routine (208). Furthermore, k(JT) is added to this integral term.
The control signal [X] can be seen by adding it to 1 (20
91° K in the above equation. This is a constant determined by the τ control system. Details of the above-mentioned PI arithmetic processing are described in Japanese Patent Application No. 55-57836. The heat load corresponds to the amount of heat required, and in this example, k)0 τ>0 is selected, so when [X]>0, the heating power is greater, and the larger the [x] value, the greater the heating power % (Xl< 0 means that the cooling power is greater, and the larger [-X] is, the greater the cooling power required by the single room heat load. Based on the value of this control signal (X), the operation of this air conditioner is The explanation will be given by adding: Fig. 8 shows the horizontal axis control signal [x]
2 shows the operating state of the heat exchanger 1 with respect to FIG. First, temperature control door target voltage [Vr
o) is determined by calculation (210). This target voltage (V'ro) is a linear expression regarding [X], and [X, l are

At [0], (Vto) = [Vtt], at a predetermined positive value of [Xl [x3], (V to ] =
(Vtz). Here, [Vte1] corresponds to the voltage measured by the potentiometer 147 when the temperature control door 142 closes the passage to the heater core 141 (θ is maximum). (Vts,l is the voltage of the potentiometer 147 when the passage to the heater core 141 is completely opened (θ=0).Next, in the interrupt processing routine, the position signal of the temperature control door 142 is sent to the potentiometer 147+7)W The voltage Vrt is read and converted into a digital value [T!] by the AD converter 21 (222).Next, by comparing the target voltage [VTO] and (Vt), the position of the temperature control door 142 is controlled ( 223). First, [JVr )=(Vto) CVt For the pre-added value [ΔVtp]>0, [JVr )>
[JVtp]te'''l', [JVt:]<[JTtp
] Control signal [Tl] and [-ΔVrp
] <[Δvr)<[ΔVTp] to create a control signal [T!] which becomes @1” and 0# in a range other than the above. When the control signals CTt ] and [:T2 ) are “1”, the switch circuit 24 The corresponding switching element is turned on, and the solenoid valves 145 and 146 are energized, and are not energized when @'0''. Due to the above operation, as mentioned above, [
JVr]>(Jvyp]'t'tempg)'7142
is rotated in the direction in which the indicated θ increases, and [ΔV! 〕〈〔−∆V
yp], the temperature control door 142 is rotated in the direction in which θ decreases. [-ΔVtp]<[ΔVt]ri[)VTP)
The temperature control door 142 is in a stationary state in the range of
VTO). Returning to step (214) of the main routine, the target temperature of exhaled air Tc (T co :) is determined from the following: [X] with respect to the predetermined negative value [X3] of [X].
<[X! ], (T co ] becomes the lowest possible value (:Tc1) (2.5C in this example) at which the evaporator coating surface is about to freeze, and in the range of [X]≧[X!], j:x
]=[Xsl is the above-mentioned [Tc1], and [x:l=[0] is a predetermined value (Ta2:] (25C in this example). X] = [0) is a region where the single room heat load does not require either heating power or cooling power, and the outside air temperature To is close to the target set temperature Ts.In this region, there is almost no need to operate the cooling means. Because there is no [Tc2] ('t',,
] is set. In the next step (215), the discharge temperature target temperature (Tco
) and discharge temperature (Tc) are compared, and the temperature difference [ΔTc]
= [:Tco) [Tc] is calculated, and this [ΔTc)
A compressor operation signal [C] is generated based on the value of . That is,
[ΔTc]〉

At [0], [C] is '0'', [ΔTag<(
0), [C] becomes @11. When the compressor control signal [C] is "1", all the corresponding switching elements of the switching circuit 23 are turned on at step (217), and the compressor relay 132b is energized. The compressor relay 132b excites the magnet clasp/edge 132a2>, the compressor 132 is operated, the air passing through the evaporator 131 is cooled, and the discharge temperature Tc is lowered. If the exhaled temperature TC decreases, there will be a delusion [ΔTc]〉

[0] becomes [C] = ``0'', and the compressor 132 becomes non-operational at the final step (217) of the routine. In this way, by repeating the operation and non-operation of the compressor 132, the discharge temperature Tc is maintained close to the target temperature CT co ) which is stopped by the control signal [X]. However, as mentioned above, in the range of [X]≧0, the single-chamber heat load requires heating power and the target installation temperature 'l ['l > outside air temperature of the passenger compartment To the other side T co > T cz Ti and suction Since the entrance door 111 sucks in 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)) is 0 and the compressor 132 will not operate. Then, it becomes [TO] in [Tc, :l. The blower air volume A is approximately proportional to the voltage VF supplied to the motor 122. The voltage supplied to this motor is controlled as follows. First, in response to the control signal [X], the target voltage [
Vr] can be seen. Predetermined negative value of [X] CX
II, for positive values [X+), [x] < [xt) and [
X]〉[X4]7... Maximum value CLr1] (12V in this example), the negative value (X2), the positive value [at Xsl]
vF] to the minimum value [Vy2] (4V in the example (2))
,! :do. [X1] In the range of ku [x) ku (xz]
From the linear equation connecting the two points, (VFI) at [Xl] and [Vr*] at [X2], 1:vyjt is constant, CXs]<[
:X]<[X4:], ['Vr*) at [X3]
, l: The converter 239 converts it into an analog voltage VFII, and this voltage VFI
Motor 12 by driver circuit 123 controlled by
The voltage Vv applied to 2 is controlled and driven. Depending on the value of the control signal [X], when [X+E or lower, Vy is the maximum, that is, the blower air volume A becomes the maximum AMAI, and [Xl] and [
Between [X2] and [X2], the blower air volume decreases almost linearly from the maximum value Ayhx to the minimum value AMIN, and between [X2] and [X3], the blower wind itA is kept at the minimum value A w t N, and - (Xs) and Between [X4], the blower air volume A is the minimum value A
increases linearly from M I H to the maximum value AMAI,
I: Similarly, the mode door 151 is also controlled by the value of control number H [x]. [03<Cxs]<Cxt'J<Cxz) [x@
). [X7] is predetermined. 'l' for [x] and [X7], 'l' for [x]>[xy]
When the control signal [O1] becomes 0# and [x] is [X6], M
1pp, control signal [0] which becomes 10'' at [x]q[x+]
2] is created (212). The mode door 151 is driven as follows in step (217) according to the value of the control signal [01]1 (02). At Cx] and [x6], * (O1] and [Oi) are both '1'.
#, switch elements 236 and 237 are both turned on, solenoid valves 154 and 155 are both energized, and mode door 1 is turned on.
51 is brought into the top blowing state by the actuator 152. If CxE>CxtE, %(01 and (Oa) are both ON, the solenoid valves 236 and 237 will not be energized. The mode door 151 will be in the downward blowing state by the return spring 153. ]<, CXt], [O1] is 11”
. [02] becomes 10”, so the solenoid valve 154 is energized,
Since the electromagnetic valve 155 is not energized, the mode door 151 is in an intermediate position, and is in an upward and downward blowing state. FIG. 9 shows the principle of an automatic temperature control system consisting of the air conditioner shown in FIG. 1 and a single room heat load, which have been explained above. The flow of variables between the operating section 3, the control section 2, and the heat exchange section 1 is as explained above. The AAA heat load receives disturbance heat Q4 in addition to receiving pAfQ from the heat exchanger l. The disturbance heat Qd includes heat generated by the occupants and other factors that enter the vehicle from outside the vehicle. Single room heat load is Q+Qa heat!
When all received, if it is a heating amount, the cabin temperature TR increases with a first-order lag, if it is a cooling amount, it decreases, and if it is 0, it remains unchanged. This negative R control using PI performance: 4 is a method increasingly used in the field of automatic control, and is ΔT)0(ΔT〈0)
In this case, the relationship between the PI calculation section and the heat exchange section is selected so that Q can be changed in a direction in which room temperature TR approaches target temperature T8, that is, heat fQ' can be increased (decreased). Furthermore, for the two constants of the PI calculation, select the relationship between the PI calculation and the heat exchanger so that if r is positive, %Q increases uniformly with respect to X, and if r is negative, it decreases monotonically. For example, it has been theoretically and empirically confirmed that Tm stably converges to Ts (ΔT-0). It is well known to apply this negative feedback control to an air conditioner for an automobile (for example, Japanese Patent Application No. 105077/1982). In this embodiment, r)Q is selected as the constant for the PI calculation, so it is essential that it increases monotonically and uniformly with respect to the amount of heat Q75KX. How the object of the invention is achieved in such a control system will be explained with reference to FIG. Note that the cooling power is treated as a negative heating amount here. The amount of heat Q is the sum of the amount of heat Q, m of the air heated by the heater core 141 and the amount of heat Q, e of the air that passes through the bypass path 199 after passing through the evaporator 131. In order to make it easier to understand all the basic characteristics, the reference point is a state in which the vehicle interior TR is maintained at the target set temperature Ts. The air temperature immediately after passing through the heater core 141 is Ti,
If the air volume passing through the heater core 141 during the air volume A of the blower 121 is t-AM, then Q, a cI: (Tn Tm
) Am, Qc cI: (Tc-Ti) (A-An)
It is. Here, in the range [xs:]>[x)>(0], Q=
QH+Qccc (Ta TR) AR+(To −Tm
l (AMIN-person g), and assuming that the heating means has sufficient capacity, (Tg-TR) is approximately constant. Also,
The air volume Ai+ passing through the heater core 131 is 0 to AMI
Since QII increases linearly during N, QII increases linearly from 0 with respect to an increase in [x]. Also, near [X:]=[O), T o y T 1
% Therefore, 0 in Qc, and [x] = [x3], A *
= A M is 1, so Qc=0. Furthermore, Ta<. Because of TII, Qc≦0. Therefore, the amount of heat Q has a characteristic as shown in FIG. In the range [x]≧[x3], Ayz=A. Therefore, Q=Qu oc (Tg −TR) A,
('I'RTRl is constant and the air volume A changes linearly with [X), so the amount of heat Q increases more linearly as (X) increases. [x]

In the range [0], An=O, and assuming that the cooling means has sufficient capacity, the target discharge temperature T in the discharge temperature Tc
It is CO.

In the range [0]>[X]n[x2], Q, = QCα
(Tc Ti) AMt* with constant hAyuw [X]
Since % (Tc-Tm) changes linearly from 0 to TCI TR as % (Tc-Tm) increases in the negative direction, the amount of heat Q increases linearly from 0 as the cooling power (X) increases in the negative direction. In the range [Xm]>(X)>(Xt:], TcTR
I is T(! TR = (TCI Tl) = 1 Since A is a constant negative value and changes linearly with (X), as [X] increases in the negative direction, the heat fQ increases as the cooling power From the above, it can be seen that the amount of heat Q increases continuously and monotonically with respect to [X] as shown in Fig. The above-mentioned range of X'20 is a heating area, so it is not necessary to drive the compressor in order to control the temperature inside the vehicle at a constant temperature.However, in order to dehumidify the vehicle interior, , the compressor system # is performed as follows. First, in step 209 of the main routine in FIG.
] is output, and if the value is positive, the compressor is controlled as shown in FIG. That is, a step is provided between step [213] and step (215) to determine whether %x (CX) is positive or negative, as shown in FIG. Proceed to (same as Figure 6), x'; 20, that is, during heating, the outside air will cause 'I'c. All settings are made. [x] = 0 means that neither cooling nor heating is required, but it is generally comfortable. In the case of Ts=25C, the condition for [X)=0 is that the outside air is around 23C. Also, when x>0, since outside air is introduced, the suction temperature of the evaporator 131 is Although there is a slight increase due to the heat from the outside, it can be considered that the temperature is almost the same as the outside temperature. Therefore, when the outside air is about 23C and ,
T coH is determined so that it remains on until the temperature drops to 5C. Furthermore, at low temperatures, TcoLf is set at a location where the outside air is equal to Tc1 (2.5C in this embodiment), at which the evaporator 131 is about to freeze. During heating, the compressor 131 is driven by the TCO expressed by a linear equation connecting these two points T coH and T COL f. At the point where the outside air is lower than 2.5C, the compressor 131 is not turned off. The compressor 131 is driven by the above-mentioned throughput [Tco].
By comparing and [Tc), the difference [ΔTc) = [Tc
o] (Tc) is positive, the compressor 131 is turned on, and when it is negative, it is turned off, so that the discharge temperature Te is maintained approximately at Tco. The setting of ] may be determined by the value of [X] instead of the outside temperature, but [X] is calculated by calculating the difference between the set temperature [T8] and the single room + m [Ti] and using the 'fc result. Therefore, it is not generally determined by the outside temperature, but varies greatly depending on the set temperature.Also, as the cabin !Tm approaches the set temperature, its value decreases, so Tco due to [X] With this setting, the compressor drive ratio changes even for the same outside temperature.Therefore, it is more reliable to control using outside air from the viewpoint of dehumidification.Also, as shown in Fig. 13, In the x>00 heating region, dehumidification is possible even if the duty is constant regardless of the on/off control sound of the compressor 131 or the outside temperature.Furthermore,
The duty of this on-off state may be changed depending on the outside temperature, such that when the outside air temperature is high, the on-time ratio is increased, and when the outside air temperature is low, the on-time ratio is decreased. In this embodiment, the duty ratio is 10% at a constant time,
When variable, it is 20% for outside air at 23C and 0% for OC. Although the above explanation has been given for the case of an automatic air conditioner, the same effect can be obtained in a so-called manual air conditioner by adding a circuit that limits the compressor capacity in the various ways mentioned above during heating. I can do it. [Effects of the Invention] According to this invention, by having one or more configurations,!
l) An air conditioner for automobiles that limits the capacity of the compressor during heating, greatly reduces the consumption of unnecessary power, and does not cause inconveniences such as fogging of the window glass in order to continue blowing cold air to a certain extent. i-Can be provided.

[Brief explanation of drawings]

Fig. 1 is a general configuration diagram of a heat exchange section of an air conditioner using the beam heat air mix method, Figs. 2 to 4 are explanatory diagrams of the operation of a conventional heat exchange section, and Fig. 5 is a system diagram of an embodiment of the present invention. ,
6 to 8 are explanatory diagrams of the operation of the embodiment shown in FIG.
The figure is a schematic configuration diagram of the operating principle of FIG. 5.
FIG. 3 is an explanatory diagram of the main controls of the embodiment of the present invention. "...Heat exchange Q, 2-...Control section, A...Operation section, 2
2...Microcomputer, 111...Intake door. 121... Blower, 131... Evaporator, 14
2...A/M door, 151...Mode door% 15
6 river def door. Taku 2 Fig. 3 - D No. L# - Fig. (arrow) Ko (shi) Heat 8 -, 1 Figure (215) No. 3 IIXI

Claims (1)

[Claims] 1. An evaporator that introduces inside and outside air and exchanges heat to form cold air, a compressor that drives this evaporator, and a heater core that adjusts and forms the amount of heat supplied into a single room;
An automatic military air system comprising an air mix door that mixes cold air from the evaporator and warm air from the heater core in an appropriate ratio, and a mode door and a differential door that blow out all the air formed through the air mix door into a single room in an appropriate blowing direction. In the harmonizer. An air conditioner for an automobile, comprising a control device that controls the duty of the compressor according to the heat load during cooling, and controls the duty of the compressor according to the outside temperature when dehumidification is required during heating.