JPS632805B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automobile cooler or air conditioner (hereinafter referred to as an air conditioner). In recent years, an increasing number of automobiles have been equipped with air conditioning systems to provide greater comfort to vehicle occupants. Air conditioners usually consist of a heater for heating, a cooler for cold protection, and their control equipment, but as is well known, in order to operate the cooler, the compressor must be operated by power from the engine. . However, operating the compressor usually requires a large amount of power, which has the drawback of reducing the net output of the engine or deteriorating fuel efficiency. Many studies have been conducted to overcome these drawbacks, but they can be broadly classified into two types.
One is about improving the air conditioner itself (e.g. improving efficiency by improving the compressor, improving refrigeration cycle efficiency by improving various devices, etc.), while the other is about improving the heat load placed on the air conditioner (e.g. , reducing the amount of heat that enters the vehicle interior by changing the window glass from ordinary plate glass to heat ray absorbing glass, etc.). The present invention belongs to the latter category, and aims to reduce the required power of the compressor by effectively reducing the heat penetrating into the passenger compartment, thereby preventing a decrease in the engine's net output and deterioration of fuel efficiency. It is something to do.

Incidentally, automotive air conditioners are generally configured to be able to selectively switch between introducing air into the vehicle interior and introducing air outside the vehicle, and usually operate an inside/outside air switching damper via a mechanical operation transmission mechanism. ing. However, in conventionally known air conditioners, there is no guarantee that the position setting of the inside/outside air switching damper is always maintained optimally. This is because when the inside/outside air switching damper is operated to the position where only the air inside the car is taken in, if this state is maintained for a long time, the air inside the car becomes contaminated with exhaled air and cigarette smoke, while If the air switching damper is placed in a position where only the air outside the vehicle is taken in, a large amount of high temperature outside air in the summer is taken in, and the heat load imposed on the air conditioner increases extremely, which in turn leads to deterioration of the vehicle's fuel efficiency. Therefore, it can be understood that there is an optimum amount of outside air intake. However, the optimum amount changes from time to time because it depends on many factors such as the number of passengers, outside temperature, interior temperature, and whether or not smoking occurs. On the other hand, since it is troublesome for the passenger to frequently adjust the optimal amount, which changes from moment to moment, the passenger usually sets the outside air amount so that it is always a little larger than the optimal outside air amount. Therefore, more outside air than necessary is drawn in, resulting in an increase in heat load.

As mentioned above, conventionally known air conditioners have the disadvantage that although the adjustment is left to the passengers, they are not actually adjusted due to the complexity, which leads to an increase in heat load. have.

In view of the above-mentioned circumstances, the present invention automatically detects what kind of air conditioning is required, achieves the maximum effect with the minimum amount of cooling (or heating), and reduces the heat load, thereby reducing fuel consumption. The purpose of the present invention is to provide a simple and highly reliable air conditioning system for automobiles that can be improved.

The present invention will be described below with reference to a first embodiment shown in FIGS. 1 and 2. In Fig. 1, 1 is an air intake duct outside the vehicle, 2 is an air intake duct inside the vehicle, 3 is an inside/outside air switching damper 3, and both ducts 1,
Adjust the amount of communication between 2 and the main duct. 4 is a blower motor, 5 is a blower, 6 is an air cooling heat exchanger (evaporator), 7 is an air heating heat exchanger (heater core), 8 is a temperature control damper that adjusts the amount of air passing through the heater core 7 and blows it out. Adjust the temperature of the air. Note that the adjustment mechanism may be a manual operation transmission mechanism or an automatic position control device. 9 is an air mix chamber, 10 is a defroster outlet, 11 is a footwell outlet, 12 is a driver's seat side outlet, 13 is a passenger side outlet, 14, 15, 1
Reference numerals 6 and 17 are outlet switching dampers, and a manual operation transmission mechanism or an automatic position control device is used. The above-mentioned configuration is known as a cold air/warm air mixing type automobile air conditioner.

Reference numeral 18 denotes a light scattering type particulate detector, which is attached to the vehicle interior air intake duct 2 and generates an output signal corresponding to particulates such as smoke contained in the inhaled air. A control circuit 19 controls the actuator 3 that drives the damper 3 in response to the output signal from the detector 18.

Now, to explain the summer cooling time, the dampers 3, 8, 14, 15, 16, and 17 are normally operated to the solid line position. Here, the inside/outside air switching damper 3
is at the solid line position and is the cabin air intake duct 2.
is open, but there is a slight gap between it and the cabin air intake duct 1.
6m ³ /h) of outside air is taken in. This amount is usually sufficient to cover the exhalation of one driver. As the concentration of particulates inside the vehicle increases, control circuit 1
When the set value determined at 9 is exceeded, the actuator 20 is actuated and the damper 3 is moved in the direction of the broken line. As a result, about 50 to 100 m ³ /h of air outside the vehicle is taken in, and when the smoke concentration falls below the set value, the damper 3 is moved in the direction of the solid line by the control circuit 19 and the actuator 21.

FIG. 2 shows the particle detector 18, control circuit 19, and actuator 20. In the detector 18 shown in cross section, 181 is a resin housing;
182 is a hollow air passage, 183 is a light source bulb,
Reference numeral 184 denotes a photodetector made of a GdS cell, and the light receiving surface of this detector 184 is arranged to be parallel to the light emitted from the light bulb 183. This detector 180 is installed at a position where external light does not enter from the entrance 185 and exit 186 of the air passage 181 in the duct 2 . Therefore, due to the air flow passing through the duct 2, an air flow shown in the direction of the arrow is generated in the air passage 182, and if this air flow contains particulates such as cigarette smoke, the light bulb 183 will emit light. The scattered light scattered by the fine particles is detected by the photodetector 18.
4, the resistance value between the output terminals changes. The internal resistance of this detector 184 is almost infinite when there are no particles in the air particles,
If there are fine particles such as smoke, the resistance will be several kilohms.

In the control circuit 19 that responds to the resistance value between the output terminals of the detector 18, 19A and 19B are the first and second
This is a switching circuit. 191 is the detector 18
4 and generates a signal voltage Vs at the connection point with the detector 184 according to the resistance value of the detector. 192 is a voltage comparator that compares the signal voltage Ws with the first set voltage _V1 , and if the voltage Vs is higher than the voltage _V1 (that is, if the amount of fine particles is less than the set amount),
The relay 193 is energized via the transistor circuit to make the contacts 193A-193B conductive. Comparator 1
94 is the aforementioned detector signal voltage Vs and the 'th set value V ₂
(smaller than the first set value) and compare the voltage Vs
When V2 is lower than the second set value _V2 (that is, the amount of particulates is greater than the set amount), relay 195 is energized via the transistor circuit, causing contacts 195A-195B to conduct. To summarize the functions of the control circuit 19,
If the amount of fine particles is less than the first set amount, relay 193
is energized and the first output signal _S1 becomes high level, and when the amount of fine particles is greater than the second set amount, relay 19 is activated.
5 is activated, and the second output signal _S2 becomes high level. If the amount of particulates is an intermediate amount between the first set amount and the second set amount, the relays 193 and 195 are both deenergized and the first and second output signals S ₁ and S ₂ are at the open level. Become. Note that 21 is an automobile key switch, and 22 is an in-vehicle battery.

In the actuator 20, 201 is a reversible motor that drives the rotating shaft 2 through a reducer 202.
03 to drive the inside/outside air switching damper 3. The second output signal S ₂ is applied to the terminal 204 of the motor 201, and the first output signal S ₁ is applied to the terminal 205. When the first output signal _S1 becomes high level, the motor 201 rotates counterclockwise to move the damper 3 in the direction of the arrow L in FIG. 2b (that is, in the direction of the solid line in FIG.
When S ₂ reaches a high level, the motor 202 rotates clockwise to move the damper 3 in the direction of arrow R in FIG.
(in the direction of the dashed line in the figure).

In the above-described configuration, when the key switch 21 is turned on, the control circuit 19 is put into operation, and at the same time, the light source bulb 183 is also energized via a power supply path (not shown) and becomes illuminated. Now, the first
When the air conditioner shown in the figure is operating and the amount of particulates in the passenger compartment is less than the first set amount, the first output signal _S1 becomes high level, and the inside/outside air switching damper 3 is moved to the solid line position in FIG. 1. . Therefore, as described above, a large amount of air inside the vehicle and a small amount of air outside the vehicle are sucked into the air conditioner. When the number of particulates in the vehicle interior increases due to smoking, etc., the amount of scattered light reaching the light receiving surface of the photodetector 184 increases accordingly, and when the number of particulates exceeds the second set amount, the second output signal _S2 becomes high level. The damper 3 is moved in the direction of the broken line in FIG. 1, and a large amount of air outside the vehicle compartment is taken in. As a result, after a while, when the particulate concentration decreases and becomes lower than the first set amount, the first output signal _S1 becomes high level and the damper 3 is returned to the solid line position. Thus, the damper 3 is moved to introduce air outside the vehicle only when the amount of particulates is large, and its position is controlled so as to prevent contamination of the air outside the vehicle and to obtain a state with a small heat load.

Here, the advantages of the above-mentioned particle detector will be added. First, the light scattering type particle detector of the present invention is the cheapest, and is cheaper than using, for example, a CO sensor or a CO ₂ sensor for the same purpose.
Furthermore, this detector has much higher sensitivity than smoke sensors (combustion type) normally used for household fire alarms, etc., and has the feature of responding to even the slightest change in the amount of particulates. There is.

Furthermore, even when there is no smoking in the vehicle interior and only human exhalation, as CO ₂ increases, the number of airborne particles also increases in direct proportion. This is due to the influence of particles and water vapor in the exhaled breath, but even in this case, it is even possible to estimate the CO ₂ concentration to some extent by measuring the particulate concentration. Therefore, rather than using CO, CO ₂ sensors, etc., which are expensive and have problems with sensitivity,
It is cheaper and easier to use a light scattering type particle detector.

A second embodiment of the present invention is shown in FIGS. 3 and 4. In this example, in contrast to the first embodiment, a particulate detector 23 is also installed inside the vehicle outdoor air intake duct 1, and a signal from a limit switch 25 responsive to the position of the inside/outside air switching damper 3 is added to the control circuit 24. However, it has been improved to drive the actuator 20. As shown in FIG. 4, the control circuit 24
is the portion 24A responsive to the detector 18 and the detector 23
24B. The circuit 24B generates a third output signal _S3 which is at a high level when the number of particles passing through the detector 23 is more than a set amount, and at an open level when it is less than a set amount.

The limit switch 25 is the internal/external air switching damper 3
is turned off when it reaches the closed position α (a small amount of air outside the vehicle is taken in), remains off when it approaches the fully closed position β, and turns on when it is more open than the closed position α. The limit switch 25 is connected in parallel with the third output signal S3 of the circuit 24B, and is connected to the first output signal _S3 of the circuit 24B.
It is inserted in series in the circuit through which _S1 passes, and controls the left rotation of the actuator motor 201.

Therefore, when the air outside the vehicle is clean and the amount of particulates is below the set amount, the third output signal _S3 is at the open level. Therefore, the same operation as in the first embodiment is performed regarding the presence or absence of particulates in the air inside the vehicle.
However, in this case, due to the on/off operation of the limit switch 25, the damper 3 does not move beyond the closed position α in the closing direction. On the other hand, when the air outside the vehicle is dirty (for example, when driving in a factory area or passing through a crowded intersection), the third output signal _S3 becomes high level. Therefore, limit switch 2
Since the damper 3 closes to the fully closed position β regardless of the operation of the damper 5, dirty outside air can be completely blocked.

As described above, the present invention can reduce the heat load while maintaining the necessary and sufficient inside air condition by automatically taking in the necessary minimum amount of outside air, thereby reducing vehicle fuel consumption. This has an excellent effect.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram showing the first embodiment of the present invention, FIG. 2a is a detailed configuration diagram showing the main parts, and
FIG. 2B is a view of the actuator 20 shown in FIG. 1... Vehicle outdoor air intake duct, 2... Vehicle interior air intake duct, 3... External/internal air switching damper, 18... Particulate detector, 19, 24, 24A
... Control circuit, 20 ... Actuator.

Claims (1)

[Claims] 1. In an automotive air conditioner capable of introducing air into the vehicle interior and outside the vehicle, a particle detector in which a light emitting element and a light receiving element are arranged diagonally, and the light receiving element generates an output signal in accordance with the particle concentration between the two elements. is placed in the vehicle interior or in the vehicle interior air passage, and is equipped with a control circuit that responds to the output signal, and when the concentration of particulates exceeds a set value, the inside/outside air switching damper is actuated by a predetermined small angle to introduce air into the vehicle interior. An air conditioner for an automobile, characterized in that the control circuit is configured to increase the rate of air introduction from outside the vehicle from the state shown in FIG.