JPH0447218B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an air conditioner, and particularly to a humidity control device for an air conditioner suitable for preventing problems due to delayed response of humidity detection means at low temperatures.

[Background of the invention]

Conventional devices only correct the temperature dependence of the humidity sensor, as disclosed in Japanese Patent Application Laid-Open No. 57-144835, but in order to eliminate the response delay of the humidity sensor at low temperatures,
No consideration was given to predicting the actual humidity, and even less to the fact that the accuracy of the prediction deteriorates as the temperature decreases.

[Purpose of the invention]

An object of the present invention is that when predicting actual humidity from detected temperature and humidity, the lower the temperature, the longer the response time constant becomes and the prediction accuracy becomes worse. Therefore,
An object of the present invention is to provide an air conditioner that does not cause a problem that occurs when the predicted humidity is lower than the actual humidity, such as fogging of windows in automobile applications.

[Summary of the invention]

The present invention includes a temperature detection means, a humidity detection means,
In a humidity control device for an air conditioner, the humidity control device for an air conditioner has a means for temperature-correcting a humidity signal outputted by the humidity detection means with a temperature signal outputted by the temperature detection means and outputting a detected humidity. means for determining a coefficient; means for calculating and outputting a response time constant based on the coefficient and the temperature signal of the temperature detecting means; and calculating and outputting actual relative humidity by inputting the response time constant and the detected humidity. and the means to do so.

[Embodiments of the invention]

An embodiment of the present invention will be described with reference to FIGS. 1 to 11.

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 [T _S ] set by the operation unit 3 is compared with the indoor vehicle temperature [T _R ], and the temperature difference ΔT=T _S −T _R is calculated by PI. If the result of the PI operation is set as x, the following equation holds true.

[x] = k ₁ [∆T] + k ₂ ∫ [∆T] Dt PI calculation is a method commonly used in the field of automatic control, and as seen in the above equation, it calculates the proportion of the difference between the target and the actual state of the controlled object and time. and the accumulated amount, and calculate the required amount required to shift the controlled object to the target state. The heat exchanger 1 drives the heat exchanger 190 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) is subjected to disturbance heat Q _D in addition to the above-mentioned amount of heat Q. Disturbance heat Q _D includes heat entering from outside the vehicle, radiant heat due to eye radiation, heat transferred from the engine compartment, heat generated by the occupants, etc. The air inside the vehicle receives a heat amount of Q + Q _D , and the temperature [T _R ] changes with a first-order lag. This [ _TR ] is negatively fed back to the control section 2. In such a negative feedback control system, automatic temperature control is achieved because it is mathematically proven that [T _R ] stably converges to [T _S ] if the coefficients of each element are appropriate.

The air conditioner according to the embodiment shown in FIG. 2 will be described below.

The heat exchange section 1 is provided with an outside air suction port 102 for sucking air from outside the vehicle interior, an inside air suction port 101 for sucking air inside the vehicle interior, and a suction port door 111 for controlling the opening and closing of these suction ports. The suction door 111 is controlled to three positions by a two-stage action negative pressure actuator 112 and a return spring 113. That is, this negative pressure actuator 11
Each negative pressure operation chamber of 2 is provided with a solenoid valve 114, 11.
5, the suction port door 111 is connected to a negative pressure source such as a negative pressure pump 90 (not shown), and when both the solenoid valves 114 and 115 are not energized, the suction port door 111 is closed to the outside air suction port 102 by the force of the return spring 113. is closed and enters a state of internal air suction. When both the solenoid valves 114 and 115 are energized, the negative pressure supplied to both negative pressure working chambers of the negative pressure actuator 112 closes the internal air suction port 101 and enters a state of external air suction. . In addition, the solenoid valve 114 is energized, and the solenoid valve 1
When 15 is not energized, negative pressure actuator 1
Since the negative pressure acts on only one of the negative pressure working chambers 12, the suction port door 111 is stopped at an intermediate position in the above-mentioned state, and both the inside air suction port 101 and the outside air suction port 102 are opened, and the inside and outside air is sucked.

The heat exchange unit case 100 is provided with a blower 121 that sucks air from the suction port and sends it to the heat exchange unit, which will be described later. The air volume by the blower 121 is controlled by controlling the applied voltage supplied to the motor 122 by a driver 123 controlled by the control unit 2. Blower 1
An evaporator 131 is provided downstream of 21, and this evaporator 131 is connected to a compressor 132 and an expansion valve 133.
This constitutes a compression refrigeration cycle, and serves as a means of cooling the air that passes through it.

The compressor 132 is driven by the automobile engine via an electromagnetic clutch 132a, and its driving and non-driving are performed by energizing or de-energizing the electromagnetic clutch 132a by a compressor relay 132b controlled by a control signal from the control section 2. It will be done.

Furthermore, a heater core 141 serving as a heating means is provided downstream of the evaporator 131, and engine cooling water (warm water) of the automobile is circulated through the heater core 141 to heat the air passing through the heater core 141. 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 the negative pressure source 90 via the solenoid valves 145 and 146.
It is rotated by a negative pressure actuator 143 and a return spring 144 connected to. Solenoid valve 14
5, 146 When both are not energized, the negative pressure operating chamber of the negative pressure actuator 143 is connected to the solenoid valve 14.
5, 146 to the atmosphere, and the return spring 144 causes the temperature control door 142 to rotate in the direction in which θ decreases in FIG. 2. In other words, it passes through the heater core 141. This will increase the amount of air. When the solenoid valve 145 is energized and the solenoid valve 146 is not energized, the negative pressure operating chamber of the negative pressure actuator 141 is connected to the solenoid valve 1.
It is connected to a negative pressure source through 46 and 145, and 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 converts a position signal corresponding to the position of the temperature control door 144 into a voltage.
It is input to 148 of the control unit 2 in the form of V _T , and V _T increases as θ increases. With the above configuration, the temperature control door 142 controls the amount of air passing through the feedback-controlled heater core 141 from 0 (θ is maximum) to 100% (θ is 0) of the blower air volume A sent by the blower 121. In addition, air that does not pass through the heater core 141 passes through a bypass 103 provided in parallel to the heater core 141 and passes through the heater core 141.
It mixes with heated air and is blown into the vehicle.

The air that has passed through the evaporator 131 and the heater core 141 or the bypass 103 is sent to the upper air outlet 10 into the vehicle interior.
4. The air is blown into the interior of the vehicle from the lower air outlet 105 or the air outlet 106 to the windshield. A mode door 151 is provided to switch the air outlet into the vehicle interior, and this mode door 151 also has a two-stage action negative pressure actuator 1 similar to the intake door 111.
52, it is controlled to three positions. The two negative pressure working chambers of the negative pressure actuator 152 each have a solenoid valve 15.
4, 155 to the negative pressure source 90, and when both the solenoid valves 154, 155 are not energized, the upper outlet 104 is closed by the return spring 153 and the air is transferred to the lower outlet 1.
It is blown out from 05. Also, solenoid valves 154, 155
When both are energized, the negative pressure source 90 is connected to both negative pressure working chambers of the negative pressure actuator 152, and the mode door 151 closes the lower air outlet 105.
The air is blown out from the upper outlet 104. When the solenoid valve 154 is energized and the solenoid valve 155 is not energized, only one of the negative pressure working chambers of the negative pressure actuator 152 is connected to the negative pressure source 90, so the mode door 151 is in the intermediate position in the above state, and in the top position. Exit 10
4. Both lower air outlets 105 are in an open state, and the air is blown out from both air outlets, which is a so-called bilevel state. The air outlet 106 to the windshield glass is opened and closed by a door 156. door 1
Even when the valve 56 is in the closed state, a small amount of air is normally discharged.

The door 156 is actuated by a negative pressure actuator 157 connected to the negative pressure source via a solenoid valve 159 and a return spring 158. Solenoid valve 15
9 is energized, negative pressure acts on the negative pressure actuator 157, and the differential door 156 opens against the return spring 158. When the solenoid valve 159 is not energized, the door 156 opens against the return spring 158.
58.

The humidifier 190 is controlled by turning the power on and off,
The on/off operation is performed by a humidifier relay 191 controlled by a control signal from the control section 2.

By a thermistor immediately downstream of the evaporator 131,
A 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 _T.sub.C , and the discharge temperature sensor 160 detects the discharge temperature _T.sub.C in the form of a voltage _V.sub.C.
61 is entered. A vehicle interior temperature sensor 170 is installed at an appropriate position in the vehicle interior, and inputs the vehicle interior temperature _TR to 171 of the control unit 2 in the form of a voltage _VR .

Furthermore, a vehicle interior humidity sensor module 180 is attached to an appropriate position in the vehicle interior, and inputs the vehicle interior humidity RH to 181 of the control unit 2 in the form of a voltage _VH .
As shown in FIG. 4, the humidity sensor module 180 includes a humidity sensor 183, an oscillation circuit 184 for applying alternating current to the humidity sensor 183, and a logarithmic conversion circuit 185. The electrical resistance of the humidity sensor 183 decreases exponentially as the relative humidity increases, as shown in FIG. Therefore,
By passing through the logarithmic conversion circuit 185, the amount of change in the output voltage V _H with respect to relative humidity is made constant, and the resolution when the output voltage V _H is taken into the microcomputer 22 and converted into relative humidity is made uniform. There is. FIG. 6 shows the output voltage characteristics of the humidity sensor module 180. However, since the electrical resistance of the humidity sensor 183 has temperature dependence, the output voltage V _H also has temperature dependence.

Humidity sensor 18 of humidity sensor module 180
As shown in FIG. 3, an example of a mounting location for the vehicle interior temperature sensor 170 is near the vehicle interior temperature sensor 170, and the same aspirator 182 as the vehicle interior temperature sensor 170 is installed.
so that it comes in contact with the air inside the car that is inhaled.

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 which controls each device of the heat exchange section 1 using output signals from the microcomputer 22. This interface circuit 23 includes the solenoid valves 114, 115, 145, 146 of the heat exchange section 1,
154, 155, 159, compressor relay 132b, transistors 231 to 239 as switch elements that control the humidifier relay 191, and a D/A converter 24 for supplying analog voltage to the driver 123 that supplies power to the motor 122.
Consists of 0.

The operation unit 3 includes an air conditioner switch (not shown) for starting and stopping this device, a temperature setting device 31 for setting the desired temperature in the vehicle interior, and an operation for blowing air from the air outlet 106 onto the windshield. It is composed of a switch 33 and the like. Desired temperature of the passenger compartment set by the above temperature setting device (target set temperature
T _S ) is input to the control unit 2 as a voltage V _S , and the operation signal V _DEF of the switch 33 is also input to the control unit 2 in the form of a voltage.

The operation of the automatic air conditioner according to this embodiment with the above configuration will be explained.

7a, 7b, and 7c 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 initialization steps 201 to 203, and steps 204 to 203.
An interrupt routine that processes steps 220 to 227 at a period several tenths of a second (one hundredth of a second in the example) compared to one cycle of the main routine that repeats step 217 an infinite number of times (approximately 0.5 seconds in the example). Consisting of

First, when this device is activated by the air conditioner switch, the microcomputer 22 of the control section 2
The output terminal of is set to a predetermined initial state in step 201, and the initial value is written in a random access memory (RAM) not shown in the microcomputer 22 in step 202. Next, in step 203, the voltage V _T of the potentiometer 147 corresponding to the position (θ=0) of the temperature control door 142 is converted into a digital quantity [V _T ] by the A/D converter 21, and Read as initial value. Note that this door reference position signal is monitored and monitored in step 224 of the interrupt routine described later.
Updated.

Next, the main routine will be explained.

Voltage V _S corresponding to the target set temperature T _S set by the operation unit 3 , voltage corresponding to the vehicle interior temperature T _R
V _R and the voltage V _C corresponding to the exhaled air temperature T _C are converted into digital values [V _S ], [V _R ], and [V _C ] by the A/D converter 21 in step 204, respectively. is input. Cabin humidity
The voltage V _H corresponding to RH is read in step 206, and the voltage V _T corresponding to the position of the temperature control door 142 is read in step 222 of the timer interrupt. [V _R ],
In step 205, [V _C ] is converted into digital values [V R ] and [V _C ] corresponding to the cabin temperature and the exhaust air temperature using a voltage → temperature conversion map stored in a read-only memory (ROM (not shown) of the microcomputer 22 ₎ . ] is converted to

The cabin humidity RH is determined in step 206, and the detailed flow is shown in FIG. 7b. As shown in FIG. 8, the response of the humidity sensor 183 when the humidity is changed stepwise differs depending on moisture absorption, moisture removal, and temperature conditions. Furthermore, in the case of a humidity sensor that does not change over time, its response time is extremely long, several tens of minutes. Therefore, the actual humidity is predicted using the following method.

The response of the detected humidity RH' by the humidity sensor 183 when the humidity changes stepwise from RH ₀ to RH is as follows:
For time t, RH'=RH ₀ + (RH-RH ₀ ) (1-e ^-t/ 〓)=
RH−(RH−RH ₀ )e ^-t/ 〓). However, α is the response time constant of the humidity sensor 183. Differentiating RH' with respect to time t, dRH'/d _t = 1/α(RH-RH ₀ )e ^-t/ 〓) Therefore, by substituting it into the previous equation, RH'=RH-α・dRH'/d _t RH = RH′+α・dRH′/d _t . In other words, the response time constant of the humidity sensor 183 and the humidity sensor 183 per unit time (ΔT)
From the amount of change in the detected humidity RH′ (RH′−RH ₀ ′) (RH ₀ ′ is the previous detected humidity), calculate the actual cabin humidity using the following formula.
Estimate RH.

RH=RH′+α・(RH′−RH ₀ ′)/ΔT The response time constant α changes depending on the cabin temperature T _R ,
It can be approximated by its linear function and can be obtained by the following formula.

α=A(T _R +B) Here, A and B are constants, and in particular, A is determined by the moisture absorption and dehumidification of the humidity sensor 183, and the on/off of the compressor 132 and humidifier 190, which function as dehumidifiers.

As mentioned above, in order to estimate the actual humidity, the humidity detected by the humidity sensor 183 per unit time is
The amount of change in RH′ is required. Therefore, the input and processing of the output voltage V _H of the humidity sensor module 180 is performed at fixed time intervals ΔT. It is determined in step 300 that a predetermined period of time specified by timer interrupt step 226, which will be described later, has elapsed, and the following processing is executed only when the predetermined period of time has elapsed. The voltage V _H corresponding to the detected humidity is converted into a digital value [V _H ] by the A/D converter 21 in step 301.
It is input to the microcomputer 22. [ _VH ]
is created in step 302 based on the characteristics shown in FIG.
The voltage and the vehicle interior temperature T _R are stored in the Relative Humidity Conversion Map and converted into a digital value [RH] equivalent to the detected humidity. The response time constant α of the humidity sensor 183 differs greatly between moisture absorption and moisture removal. Furthermore, in actual usage conditions, changes in humidity are not always simple step changes. Therefore, the compressor 132, which is a humidity control device, and the humidifier 1
90, the time constant α is changed to determine the actual humidity.
Predicting RH. The coefficient A of the response time constant α is determined by the following process. In step 303, it is determined whether the compressor 132 is on or off, and when it is turned on and dehumidifying, the moisture absorption and desorption of the humidity sensor 183 is determined in step 304, and when moisture is absorbed, it is determined in step 305.
In step 306, A is set as a constant α _CU , and during dehumidification, A is set as a constant α _Cd in step 306. It is determined in step 307 whether the humidifier 190 is on or off, and when humidifying, the moisture absorption and desorption of the humidity sensor 183 is determined in step 308, and when moisture is being absorbed, A is set to a constant α au in step 309, and when dehumidifying, A is set to a constant α _au . In step 310, A is set to be a constant α _ad . If neither dehumidification nor humidification is being performed, the moisture absorption and desorption of the humidity sensor 183 is determined in step 311, and if moisture is absorbed, step 311 is performed.
In step 312, A is set to a constant α _eu , and during dehumidification, in step 313, A is set to a constant α _ed . The relationship of constant A between each condition is α _cu > α _eu > α _au α _cd < α _ed < α _ad . From the above results, the response time constant α is determined in step 314, and the actual relative humidity RH is estimated in step 315. Then, the detected humidity [RH′] of this time is used as the previous detected humidity [RH ₀ ′] to be used next time.
shall be. (Step 316).

By the way, as shown in FIG. 8, the response of the humidity sensor module 180 becomes slower as the temperature becomes lower.
The error in the actual relative humidity RH estimated in step 315 becomes large. Therefore, in step 317, as shown in FIG. 11, a safety amount δ which increases as the cabin temperature [T _R ] becomes lower is determined. In step 318, the actual relative humidity RH estimated in step 317 is
By adding the safe amount δ to , the corrected humidity RH _C to be used during humidity control is determined.

[V _S ] is converted into a digital value [T _S ] of the target set temperature in step 207 using a first-order conversion equation. In step 208, the deviation [ΔT] between the target set temperature [T _S ] and the cabin temperature [T _R ] is determined.
[T _S ]−[T _R ] is calculated.

Next, in step 210, [X]=k[ΔT]+
A PI calculation of 1/τ∫[ΔT]d _t 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 225 of the interrupt routine, and then adding k [ΔT] to this integral term to generate the control signal. [X]
is required (Step 209). Note that k in the above equation,
τ is a constant determined by the control system.

The control signal [X] obtained in this way is an amount that meets the amount of heat required by the cabin heat load in the process of controlling the cabin temperature _TR to the target set temperature T _S , and in this example, k>0 , τ>0, so [X]
>0 means that the larger the [X] value is, the greater the heating power is required, and when [X]<0, the larger the [-X] is, the greater the cooling power required by the cabin heat load.

Hereinafter, based on the value of this control signal [X], the heat exchange section 1 of the air conditioner is controlled as shown in FIG. 9a or 9.
It is controlled by the operating characteristics shown in figure b. Fig. 9a shows an energy saving case in which the compressor 132 is operated to dehumidify regardless of the heat load in the passenger compartment, and Fig. 9b shows an energy saving case in which the target exhaust air temperature T _C0 immediately after the evaporator 131 is determined according to the heat load in the passenger compartment and the compressor 132 is operated. This is a case of control. Which operating characteristic should be used to control the heat exchange section 1 is determined based on the relative humidity RH determined in step 206 and the characteristics shown in FIG.
That is, when the humidity is high, it is dehumidified by controlling with the characteristics shown in FIG. 9a, and when the temperature is low, it is controlled with the characteristics shown in FIG. 9b to save energy. _H1 in FIG. 10 is 60%RH in this example.

In steps 211, 212, and 213, the position of the suction door 111, the position of the mode door 151, and the position of the differential door 156 at the target voltage V _T0 of the temperature control door 142 is determined based on [x] determined in step 210 and the operating characteristics of the heat exchanger 1. Decide on each. In step 214, if the discharge air temperature [T _C ] detected by the discharge air temperature sensor 160 is equal to or lower than the target discharge air temperature [T _C0 ] of the operating characteristics of the heat exchanger 1, the compressor relay _132b is turned off, and the compressor relay 132b is turned off. If this is the case, the compressor relay 132b is turned on. In step 215, the humidifier relay 191 is turned on or off based on the humidifier control characteristics shown in FIG. _H2 is 40% RH in this example.

In step 216, the analog voltage to be output to the driver 123 of the motor 122 is determined based on the operating characteristics of the heat exchanger 1 . In step 217, the actuator is controlled via the interface circuit 23 according to the pattern determined in steps 211-216.

FIG. 7c shows a timer interrupt flow diagram. In step 220, the registers of the microcomputer 22 are controlled so that the next timer interrupt is accepted. In step 221, the contents of each register of the microcomputer 22 that is currently executing the main program at the time when this interrupt occurs are stored in the RAM.
evacuate to. In step 222, the temperature control door 142
The voltage of potentiometer 147 corresponding to the position of
The A/D converter 21 converts V _T into a digital value [V _T ]
and input it to the microcomputer 22. In step 223, the target voltage V _T0 determined in step 211 described above is compared with the target voltage V _T , and the solenoid valves 145,
At 146, the position of the temperature control door 142 is controlled.
In step 224, as in the patent application No. 55-159523,
In order to determine the reference position of the temperature control door 142, the currently stored maximum heating position and maximum cooling position are compared with the current position detected in step 222, and the maximum cooling/heating position is updated. In step 225,
Interruption counting is performed to specify the predetermined time used in step 209 described above. In step 226, an interrupt count is performed to specify the predetermined time used in step 206 described above. Since this interrupt occurs at regular time intervals as described above, the number of interrupts is counted, and when the number of interrupts reaches a predetermined time, a predetermined time can be specified. In this embodiment, the predetermined time of step 225 is several seconds, and the predetermined time of step 226 is several minutes.

In step 227, the contents of the register saved in the RAM in step 221 are returned to the register, and the process returns to the next main flow process at the time of occurrence of this interrupt.

According to an embodiment of the present invention, the problem that the error in estimating the actual relative humidity becomes large due to the long response time constant of the humidity sensor at low temperatures can be solved by humidity control using a value obtained by adding correction to the estimated humidity. By doing so, the amount of dehumidification is increased, and the fogging on the windows caused by a sudden increase in humidity caused by the evaporation of snow and rain brought into the cold vehicle interior by passengers in cold regions is quickly eliminated, and the vehicle is It can be launched quickly. On the other hand, in a medium to high temperature range where the response time constant is small, the correction amount is small and dehumidification control can be kept to the necessary minimum, which has the effect of lengthening the energy saving control time.

〔Effect of the invention〕

According to the present invention, the error that occurs when estimating the actual humidity in consideration of the response delay of the humidity sensor is captured by the ambient temperature, and the operating point of humidity control is moved by an appropriate amount, so that reliable humidity control is achieved. There are effects that can be done.

[Brief explanation of drawings]

Fig. 1 is a block diagram of the principle of automatic temperature control according to an embodiment of the present invention, Fig. 2 shows the heat exchange section of Fig. 1,
The configuration and circuit diagram of the control unit and operation unit, Figure 3 is the same as Figure 2.
Figure 4 is an installation diagram of the temperature and humidity sensor module in Figure 4, and Figure 4 is a configuration diagram of the humidity sensor module in Figure 2.
Figure 5 shows the electrical resistance characteristics of the humidity sensor in Figure 4.
Figure 6 shows the output voltage characteristics of the humidity sensor module in Figure 2, Figures 7a to 7c show the processing flow of the microcomputer in Figure 2, and Figure 8 shows the response characteristics of the humidity sensor module in Figure 2. , Figures 9a-9
Fig. b shows the control characteristics of the heat exchange section in Fig. 2, Fig. 10 shows the control characteristics of the heat exchange section and humidifier in Fig. 2, and Fig. 11 shows the characteristics of the safe amount α of relative humidity in Fig. 10. DESCRIPTION OF SYMBOLS 1...Heat exchange part, 2...Control part, 3...Operation part, 22...Microcomputer, 131...
Evaporator, 180... Humidity sensor module, 183... Humidity sensor, 190... Humidifier.

Claims (1)

[Scope of Claims] 1. An air conditioner comprising a temperature detecting means, a humidity detecting means, and a means for correcting the temperature of the humidity signal outputted by the humidity detecting means using the temperature signal outputted by the temperature detecting means and outputting the detected humidity. In the humidity control device of the apparatus, means for determining a coefficient of a response time constant of the humidity detection means, means for calculating and outputting a response time constant based on the coefficient and a temperature signal of the temperature detection means, and a means for calculating and outputting a response time constant using the coefficient and a temperature signal of the temperature detection means. A humidity control device for an air conditioner, comprising means for inputting the detected humidity and calculating and outputting actual relative humidity. 2. The humidity control device for an air conditioner according to claim 1, wherein the temperature detection means is the same as a temperature detection means used for temperature control.