JPS6222801B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to temperature control that automatically brings the indoor temperature of a road vehicle closer to a target value, and furthermore, mainly relates to a temperature control system that automatically controls the indoor temperature of a road vehicle to approach a target value, and furthermore, mainly relates to a temperature control system that controls the indoor temperature of a road vehicle to make it more comfortable for occupants. The present invention relates to a temperature control method that provides a feeling of temperature control.

Conventionally, when controlling the indoor temperature of a road vehicle, sensing the heat radiation from the sun and adjusting the temperature control amount accordingly has been used to reduce the deviation of the indoor temperature from the target value, and also to reduce the deviation of the indoor temperature from the target value. It is considered desirable to soften the impression of heat radiation that is directly felt. In order to perform such correction, when electrical calculations are performed to determine the temperature control amount in order to bring the indoor temperature closer to the target value according to various control input conditions, solar energy expressed as optical energy or thermal energy is used. It has been considered to convert the thermal radiation of 200 nm into an electrical signal, and use this electrical signal to adjust the gain of electrical calculations.

As a specific method, as shown in the monthly magazine "Automobile Technology" published by the Society of Automotive Engineers of Japan, Vol. At the same time, it is known to adjust the blowing temperature depending on the magnitude of the electric signal.

In addition, as seen in Japanese Utility Model Publications No. 48-6264, No. 49-6021, and No. 54-31468, the system is equipped with an independent detection element that senses solar radiation intensity as optical energy or thermal energy. It is also known to continuously correct the temperature control amount using a detection element.

However, these known methods have the following drawbacks. First, during normal driving, a vehicle receives optical energy or thermal energy in addition to thermal radiation from the sun, and the detection element changes the correction amount in response to this, so the temperature inside the vehicle changes. This may cause problems such as fluctuations or giving the occupants an extra feeling of cooling. In addition, in order to eliminate these defects in the detection element,
Significant additional measures are required to strictly distinguish only the thermal radiation from the sun. A second problem is the variation in performance of the detection elements. That is, a photosensitive resistance element or a thermosensitive resistance element does not have uniform electrical characteristics with respect to incident light or ambient temperature, and has variations in characteristics from element to element. Therefore, in order to accurately determine the temperature control amount, it is necessary to adjust the relationship between the temperature correction amount and the electrical signal of the detection element. Methods such as modifying the entire characteristics of the element have the drawback of being too time-consuming.

In view of the above-mentioned problems, the present invention predetermines the temperature correction amount for solar thermal radiation in stages, and adjusts the electric signal generated by the detection element in response to the optical energy or thermal energy of the solar radiation received by the vehicle. Accordingly, by selecting a predetermined temperature correction amount and correcting the temperature control amount, it is possible to apply temperature correction in a large unit and perform relatively accurate temperature control without erroneous correction. Another object of the present invention is to provide a method for controlling the indoor temperature of a vehicle in which it is easy to determine a correction amount for a signal from a detection element.

The present invention will be described below with reference to embodiments shown in the accompanying drawings.

FIG. 1 shows the arrangement of the main functional elements of a temperature control device to which the method of the present invention is applied, in which 101 is an outside air inlet, 102 is an inside air inlet, and 103 is an inside/outside air switch that opens and closes both the inlets 101 and 102. Damper, 1
04 is a blower motor, 105 is a cooler made of a refrigerant evaporator of the cooling system, and 106 is a heater using engine cooling water as a heat source, which are provided in series downstream of the cooler 105 in the ventilation duct 107. 10
Reference numeral 8 denotes a temperature adjustment damper (hereinafter referred to as an A/M damper), which adjusts the ratio of the air passing through the heater 106 and the air passing through the bypass passage 109.
This is to adjust the amount of heating by step 6. 110 is an air outlet into the vehicle interior; 111 is a diaphragm actuator that opens and closes the damper 108; 112 is a negative pressure regulator that adjusts the negative pressure supplied to the diaphragm actuator 111; The negative pressure pipe 115 and the atmospheric opening 116 are opened and closed by the two solenoid valves 113 and 114, respectively.

The details and roles of each of these functional elements are the same as those known in the art, and by changing the opening degree of the damper 108, the temperature of the blown air changes, thereby changing the indoor temperature. .

FIG. 2 shows a temperature control circuit operatively coupled to each of the functional elements shown in FIG. This temperature control circuit is functionally divided into a signal generation circuit 1 that generates electrical signals according to various control conditions, and a signal generation circuit 1 that receives output electrical signals from this signal generation circuit 1 to bring the indoor temperature of the vehicle closer to a target value. an amplifier circuit 2 that determines a temperature control amount for the A/M damper 108 and controls the opening and closing of the solenoid valves 113 and 114 to adjust the position of the A/M damper 108; A detection circuit 4 includes a detection element 3 that generates an electric signal in response to optical energy of solar radiation, and generates a signal voltage according to an averaged signal of the detected electric signals; A comparison circuit 5 that determines the size step by step at two threshold levels, and an electric signal that indicates a predetermined correction amount of the size corresponding to each step determined by the comparison circuit 5. and a correction circuit 6 for converting and correcting the output electrical signal of the signal generating circuit 1.

In the signal generation circuit 1, 7 is a variable resistor for setting a target temperature, 8 is a negative characteristic heat-sensitive resistor for detecting indoor temperature (hereinafter referred to as "inside temperature sensor"), and 9 is a negative characteristic heat-sensitive resistor for detecting outdoor temperature (hereinafter referred to as "outside temperature sensor"). temperature sensor), 9
a is a correction resistor, and 10 is a resistive potentiometer for negative feedback of a signal corresponding to the position of the A/M damper 108. Here, each resistance element is connected in series, and a variable resistor 7 and a potentiometer 1
At the connection point with 0, an electric signal (voltage) V ₁ corresponding to various control conditions is generated.

The amplifier circuit 2 cooperates with the signal generating circuit 1 to constitute a known feedback type adjustment system. 1
1, 12, and 13 are voltage dividing resistors that generate comparison reference voltages V ₂ and V ₃ ; 14 and 15 are comparators;
When the voltage V ₁ is smaller than the voltage V ₃ , that is, when the measured temperature of the controlled object is lower than the lower limit of the target temperature, the level of the output line 14a is set to "0", and the comparator 15 sets the level of the output line 14a to "0" when the voltage V ₁ is larger than the voltage V ₂ . In other words, when the temperature of the controlled object is higher than the upper limit of the target temperature, output line 1
Let the level of 5a be "0". Both comparators 14 and 15 constitute a so-called window comparator. 16 and 17 are comparators 1, respectively.
This is a feedback resistor for adding hysteresis to the comparison inversion levels of 4 and 15.

Transistors 18, 19 and transistor 20,
21 constitutes an amplifier circuit that inverts and amplifies the comparison signals of the comparators 14 and 15, respectively. When the output line 14a is at the "0" level, the transistor 18 is turned off and the transistor 19 is turned on, which energizes the solenoid valve 113 to open it. Then, the temperature adjustment damper 108 is sucked toward point a in order to raise the temperature inside the vehicle. Further, when the output line 15a is at the "0" level, the transistor 20 is turned off and the transistor 21 is turned on, so that the solenoid valve 1
14 is energized to open the valve, and the temperature adjustment damper 108 is pushed back toward point b in order to lower the temperature in the vehicle interior.
When the two comparison signals of the output lines 14a and 15a are both at the "1" level, both the solenoid valves 113 and 114
The valve is deenergized and closed, and the opening degree of the temperature adjustment damper 108 is maintained to maintain the temperature inside the vehicle.

The basic operation of temperature control in this feedback type adjustment system is to adjust the opening degree of the temperature adjustment damper 108 so that the detected voltage V ₁ of the signal generation circuit 1 is located between the two threshold levels V ₂ and V ₃ . It is to decide.

The detection circuit 4 includes, as the detection element 3, a photodiode 3a that detects the amount of solar radiation through light-to-electricity conversion, and a capacitor 2 connected in series with the photodiode 3a and in parallel with each other.
2 and a resistor 23. The internal resistance of the photodiode 3a decreases as the amount of light it receives increases, increasing the voltage V ₄ at the connection point with the capacitor 22 and resistor 23. The capacitor 22 and the resistor 23 form a time constant circuit, and have the role of delaying the time until the voltage V ₄ changes to a corresponding value even if the resistance value of the photodiode 3a changes faster than the time constant.

The mounting structure of the photodiode 3a is as shown in FIG.
c and 3d are supported by the lower housing 24. 25 is a translucent hemispherical skylight through which solar radiation passes, and is fixed to the upper end of the cylindrical intermediate housing 26. The intermediate housing 26 is screwed together with the lower housing 24, whereby the ring-shaped packing 2
It is fixedly supported by the meter panel upper plate 29 via 7 and 28. The hemispherical skylight 25 may be provided with some ventilation holes. The hemispherical skylight 25 also serves as a dark filter to prevent saturation of the light-to-electrical conversion characteristics when the amount of sunlight is large, and as a color filter that mainly passes infrared rays of sunlight.

In the comparison circuit 5, 30, 31, and 32 are voltage dividing resistors that generate comparison reference voltages V ₅ and V ₆ ;
3 and 34 are comparators, and when the output voltage V ₄ generated by the detection circuit 4 received via the input resistor 35 is greater than the voltage V ₅ , the output line 33 of the comparator 33 is
The level of a becomes “0” and the output voltage V ₄ becomes the voltage
If it is larger than V ₆ , the level of the output line 34a of the comparator 34 also becomes "0". Input voltage V ₄ is reference voltage
When it is smaller than V ₆ or V ₅ , the output line levels of the comparators 34 and 33 are "open". Diodes 36 and 37 are for blocking reverse current, and resistors 38 and 3
9 is for generating hysteresis.

The correction circuit 6 includes resistors 40 and 41, one end of which is connected to each of the two comparators 33 and 34 of the comparison circuit 5, and the other end of which is commonly connected to the signal generation point of the signal generation circuit 1. It's on. Then, when the output line 33a reaches the "0" level, the resistor 4
0 is the resistance circuit 8 in the signal generation circuit 1,
9, 9a, and 10, and lowers the signal voltage _V1 at a predetermined rate. Furthermore, when the output line 34a also reaches the "0" level, the resistor 41 also acts as a shunt, further lowering the signal voltage _V1 .
Although the rate of voltage drop also changes depending on the resistance values of the related resistance elements at that time, the resistance values of the resistors 40 and 41 are made larger than the other resistance elements, and the
The amount of modification of the M damper 108 is selected to be an appropriate value.

Reference numeral 42 designates an on-vehicle battery power supply, 43 an ignition switch of a key switch, and 44 an operating switch for an air conditioner, which also energizes each operating circuit of the blower motor 104, the cooler 105, and the heater 106.

Next, the operation of the above configuration will be explained.
When the ignition switch 43 and the operating switch 44 are turned on, the air conditioner is put into operation, power is supplied to the temperature control circuit, and operation as a temperature control device is started. First, the normal operation of temperature control will be explained assuming that the amount of light received by the photodiode 3a is smaller than the threshold level and therefore there is no correction effect by the correction circuit 6.

When the vehicle interior temperature is within the target value range, the detected voltage V ₁ is within the range that satisfies V ₃ < V ₁ < V ₂ , and therefore the comparison signals of comparators 14 and 15 are both “1”. level, and the solenoid valves 113 and 114 are both closed, so the A/M damper 108 is held at a predetermined position.

When the vehicle interior temperature falls below the target value range, the signal voltage increases due to the increase in the resistance value of the inside air sensor 8.
V ₁ increases to become V ₁ >V ₂ , and as a result, the comparison signal 14a of the comparator 14 goes to the “0” level, the solenoid valve 113 opens, and the diaphragm actuator 111
As the negative pressure applied to the pump increases, the damper 108 moves to the high temperature side (to the side a in FIG. 1), increases the amount of heating by the heater 106, and raises the temperature of the blown air. As the damper 108 moves to the high temperature side, the resistance value of the potentiometer 10 decreases.
When V ₁ <V ₂ , the solenoid valve 113 returns to the closed state.

Conversely, when the temperature inside the vehicle rises above the target value range, V ₁ decreases due to the decrease in the resistance value of the inside air sensor 8, and V ₁ <V ₃ , which causes the comparison signal 15a of the comparator 15 to become "0". level, solenoid valve 1
14 opens and the negative pressure applied to the diaphragm actuator 111 becomes smaller, so the damper 108 moves to the low temperature side (side b in FIG. 1) by the force of a spring (not shown), reducing the amount of heating by the heater 106. to lower the blowing air temperature. And damper 108
potentiometer 10 by moving to the low temperature side.
When the resistance value of V ₁ >V ₃ increases, the solenoid valve 114 returns to the open/closed state.

In this way, the balanced position of the damper 108 is determined such that V ₁ is within the range of V ₃ <V ₁ <V ₂ , and as a result, the vehicle interior temperature is maintained within the target value range. . Note that when the outside air temperature changes, the resistance value of the outside air sensor 11c changes accordingly.
The potentiometer 10 moves the temperature adjustment damper 108 by the amount of change in outside temperature so as to compensate for the decrease in the detected voltage _V1 . In this way, the change in the controlled amount (change in opening degree) of the temperature adjustment damper 108
The characteristics and size of each resistance element are determined in advance so that the change in the terminal voltage of the potentiometer 10 caused by the change in the resistance value of each sensor is balanced with the voltage change caused by the change in the resistance value of each sensor.

Next, a description will be given of correction of temperature control when there is heat radiation from the sun, so-called solar radiation. The amount of light that the phototransistor 3a receives through the hemispherical skylight 25 is approximately proportional to the thermal energy that the vehicle receives from sunlight. Even when the vehicle alternately passes through sunlight and shade while driving, the output voltage V ₄ of the detection circuit 4 is appropriately stabilized and changes due to the smoothing effect of the capacitor 22 and the resistor 23.

When the output voltage V ₄ is smaller than the predetermined reference voltage V ₅ , that is, when the solar radiation is low to a certain extent, the output lines 33 a and 34 a of the comparators 33 and 34 are in the “open” state, and the signal generating circuit 1 is in the “open” state. As described above, the signal voltage _V1 is generated without correction (correction value is zero) to perform temperature control. In this state, if weak solar radiation affects the vehicle interior temperature, the inside air sensor 8 detects this and the feedback control system operates so that the interior temperature approaches the target temperature.

When the solar radiation increases, the output voltage _V4 increases, and the output line 3 of the comparators 33 and 34 increases according to the value.
3a and 34a sequentially become the "0" level. Then, due to the shunt action of the resistors 40 and 41, the output voltage _V1 of the signal generating circuit 1 is reduced in two steps. That is, the A/M damper 108 moves from the uncorrected position to b
It moves to the point side in two steps to offset the temperature rise inside the vehicle due to solar radiation.

Figure 4 shows the amount of light S received by the phototransistor 3a.
As shown in the relationship between Tg and the corrected movement amount Tg of the A/M damper 108, the temperature correction is not proportional to solar radiation but is performed in stages. In other words, the correction amount Tg
The point where this occurs is determined with respect to the amount of solar radiation S, but
The correction amount Tg itself is determined by the resistance 40, 4 of the correction circuit 6.
1. Therefore, by adjusting the generation point of the correction amount Tg using, for example, one of the voltage dividing resistors (30) for generating the reference voltage, it is possible to perform a substantially appropriate correction for solar radiation.

The temperature control device described above shows one embodiment of the method of the present invention, and can be modified within the scope of the gist of the present invention.

For example, instead of the detection element 3 responding to the amount of incident light, a heat-sensitive resistance element provided at a position that receives sunlight transmitted through the vehicle windshield may be used to extract an electrical signal in response to thermal energy. .

In addition, in order to prevent the output voltage V ₁ of the signal generating circuit 1 from decreasing stepwise at the start of correction and thereby preventing the blown air from changing rapidly, resistors 40 and 4 are connected.
The current flowing through the comparators 33 and 34 may gradually change with a time delay relative to the output inversion operations of the comparators 33 and 34. For example, the resistors 40 and 41 may be constructed of semiconductor resistance elements such as transistors, and an integrating circuit may be provided to gradually change the bias voltage of the resistors 40 and 41 in response to changes in the input signal.

Further, as in the above embodiment, the correction stages may be set to three stages including the zero level, or may be set to two stages or four stages or more.

It can also be applied to systems that perform temperature control by performing digital calculations using a digital computer called a microcomputer, which executes digital calculations according to a preset software control program. The control program is set to preferentially execute a program step that determines the level of light intensity, selects a correction value based on the determination result, and executes a program step that calculates temperature control according to that value. Good too. Furthermore, if a digital computer is used, it becomes easy to set the correction stages to four or more stages.

Furthermore, since the automobile air conditioner adjusts the amount of heat supplied to the vehicle interior by the opening degree 108 of the A/M damper and the rotation speed of the blower motor 104, thereby controlling the temperature, the above embodiment is not applicable. Like A/
In addition to correcting the opening degree of the M damper 108, it is also possible to perform correction by changing the amount of air blown by the blower motor 104. For example, two current-limiting resistors are inserted and connected to the current-carrying circuit of the blower motor 104, and a relay is activated by the "0" level signal in the comparison circuit 5 to short-circuit the current-limiting resistors to increase the amount of air blown. You can do it like this.

As described above, in the present invention, the measurement of the optical energy or thermal energy of solar radiation and the setting of the correction amount are performed independently, and the correction amount is determined in stages. This has the excellent effect of being able to perform relatively accurate and stable temperature control including solar radiation correction without problems due to variations.

[Brief explanation of the drawing]

The accompanying drawings show an embodiment of a temperature control device to which the method of the present invention is applied. FIG. 1 is a schematic diagram showing the arrangement of mechanical functional elements, and FIG. Electrical wiring diagram showing the electrical control system operatively coupled to the A/M damper) 108, No. 3
This figure is a vertical sectional view showing the mechanical structure of the detection elements 3 and 3a in FIG. 2, and FIG. 4 is a solar radiation amount S-correction amount Tg characteristic diagram showing the control characteristics of the temperature control device. 1...Signal generation circuit, 2...Amplification circuit, 3...
Detection element, 3a... Phototransistor, 4... Detection circuit, 5... Comparison circuit, 6... Correction circuit, 4
0, 41... Correction resistor, 108... Temperature adjustment damper (A/M damper), 111... Diaphragm actuator, 113, 114... Solenoid valve.

Claims (1)

[Claims] 1. In a temperature control method that determines a temperature control amount to bring the indoor temperature of a vehicle closer to a target value according to various control conditions, a detection element is generated in response to optical energy or thermal energy of solar radiation received by the vehicle. Determine the magnitude of the electrical signal step by step,
A method for controlling an indoor temperature of a vehicle, characterized in that correction data having a predetermined size that is predetermined corresponding to this step is selected, and the temperature control amount is corrected in accordance with the selected correction data.