JPS6241130B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a vehicle air conditioner, and particularly to control of the amount of outside air introduced. Generally, air conditioners for vehicles cool and heat the inside and outside air introduced into the duct using an inside/outside air switching door, adjust the mixing ratio of cold air and warm air, and then blow it out from the mode outlet. It is something. Conventionally, the amount of outside air introduced is controlled regardless of the number of passengers, so for example, when the number of passengers is small, more outside air than necessary is introduced, resulting in a large cooling load, which reduces the compressor and the engine that drives it. This has the disadvantage of placing an unreasonable burden on the occupants, which hinders the realization of low fuel consumption, and also has the disadvantage of causing insufficient ventilation when there are many occupants, causing discomfort to the occupants. For this reason, a technical concept for controlling the amount of outside air introduced according to the number of passengers is disclosed in Japanese Patent Application Laid-open No. 13744/1983. However, in order to apply this technology to automobiles, it is necessary to make further improvements. An object of the present invention is to provide a detection unit that detects the number of occupants, adjust the rotation angle of the inside/outside air switching door according to the number of occupants, and control the amount of outside air introduced in relation to the amount of air blown. The above drawbacks are eliminated by controlling the compressor based on the temperature of the inside and outside air, and will be explained in detail below using examples. FIG. 1 is a circuit diagram showing an embodiment of the vehicle air conditioner according to the present invention, and as shown in FIG.
The rotation angle θ of the inside/outside air switching door 4 located between
is automatically adjusted according to the number of passengers and the amount of air introduced from the outside air port 2. The number of occupants mentioned above is detected by a switch S ₁ installed in the passenger seat of the vehicle and a switch S ₂ installed in the rear seat. These switches S ₁ and S ₂ constitute a passenger number detection switch section, and the switch When only _S1 is on, it means that there is a person in the passenger seat, and the number of occupants is calculated assuming that there are two people including the driver. When only switch _S2 is on, it is calculated that there are two people in the rear seats for convenience, so the total number of passengers is three.
Therefore, when both switches S ₁ and S ₂ are on, there are 4 people,
When both are off, there is only one person. In addition, the amount of air introduced from the outside air port 2 is controlled by a wind pressure door 7 which rotates around a shaft 5 and is pulled in one direction by a spring 6.
The rotation angle is detected by a rotation angle detection section 8, and the detection section 8 is constituted by a variable resistor 10 whose variable terminal 9 is interlocked with the door 7. That is, when the wind pressure door 7 rotates against the spring 6 due to the wind pressure introduced from the outside air port 2, the output V ₃ of the variable resistor 10
becomes larger. The signals of switches S ₁ and S ₂ are analog switches 11
This analog switch 11 has switches a ₁ and a ₂ , switches b ₁ and b ₂ , switches c ₁ and c ₂ , and switches d ₁ and d ₂ that operate in conjunction with each other, and the switches a ₁ ,
One end of b ₁ , c ₁ , d ₁ is commonly connected to the inverting input side of operational amplifier 12, and the other end is connected to operational amplifier 1, respectively.
Resistor 13,1 as feedback resistance of 2
4, 15, 16, resistors 17, 18, 1
9 and 20. In addition, the resistor 13,
Each resistance value of 14, 15, 16 R ₁₁ , R ₁₂ , R ₁₃ , R ₁₄
satisfies the relationship R ₁₁ < R ₁₂ < R ₁₃ < R ₁₄ , and the resistance is 1
Resistance values of 7, 18, 19, 20 R ₁ , R ₂ , R ₃ , R ₄
satisfies the relationship R ₁ > R ₂ > R ₃ > R ₄ . resistance 1
7, 18, 19, 20 act as a limiter for the operational amplifier 12, one end of which is connected to the diode 2 through each switch a ₂ , b ₂ , c ₂ , d ₂ .
The cathode of the diode 21 is connected to the output side of the operational amplifier 12, and the other ends of the resistors 17, 18, 19, and 20 are commonly connected and connected to a power source. Analog switch 1 above
1. Each of the resistors 13 to 17 constitutes a first control means, which changes according to preset characteristics based on the output of the aforementioned passenger number detection switch section and the difference between the set temperature T _D and the inside air temperature tr. Outputs a signal to Its characteristics are as follows. That is, as the difference between the set temperature T _D and the inside air temperature tr increases, the outside air introduced from the inside/outside air switching door is gradually increased to a predetermined value, and as the number of passengers increases, the rate of gradual increase and This is a characteristic that increases the above value. 22 is a room temperature setting variable resistor, the output of this variable resistor 22 is connected via a resistor 23 to the inverting input side of an operational amplifier 24, and the output of the inside air temperature sensor 25 is connected via a resistor 26 to the operational amplifier 24. The output of the operational amplifier 24 is supplied to the non-inverting input of the operational amplifier 12. Note that the divided voltage of resistors 27 and 28 is connected to the non-inverting input side of the operational amplifier 24.
9. Output V ₂ of operational amplifier 12 appearing at resistor 30
is supplied to the non-inverting input side of the operational amplifier 33 via resistors 31 and 32, and the output V ₃ of the variable resistor 10 for air volume detection is supplied to the operational amplifier 33.
The output of this operational amplifier 33 is supplied to the base side of an amplification transistor 35 via a diode 34. Note that a capacitor 36 is connected to the feedback loop of the operational amplifier 33.
A parallel circuit of the resistor 37 and the resistor 37 is connected. The output of the transistor 35 is supplied to an actuator 38 for controlling the inside/outside air switching door. The operational amplifier 33 controls the actuator to open the inside/outside air switching door based on the difference between the output of the rotation angle detection section (detection section of the amount of outside air introduced) of the wind pressure door 7 and the output of the first control means. This adjusts the degree of opening of the inside/outside air switching door, thereby setting the opening degree of the inside/outside air switching door to match the output of the first control means. The output of the upper air inside air sensor 25 is supplied to the inverting input side of the operational amplifier 40 via a resistor 39, and the output of the outside air sensor 41 is supplied to the non-inverting input side of the operational amplifier 40 via a resistor 42. The output of the operational amplifier 40 is supplied to the base side of the transistor 35 and one end of the NOR circuit 44 via the diode 43, and the signal from the cooling switch 45 is supplied to the other input side of the NOR circuit 44 via the inverting circuit 46. Supplied. The output of this NOR circuit 44 is relay 4
A contact 49 of the relay 47 is connected to an electromagnetic clutch 51 for driving the compressor via an evaporator temperature detection switch 50. Note that 52 is a resistor and 53 is a diode. The operation of the vehicle air conditioner having the above configuration will be explained using the flowchart shown in FIG. 3 and the characteristic diagrams shown in FIGS. 6a, b, and c. First, when the cooling switch 45 is on, if the inside air temperature Tr is higher than the outside air temperature Ta (sixth
In section 1) of the figure a, the output of the inside air temperature sensor 25 is small and the output of the outside air temperature sensor 41 is large, so the output of the operational amplifier 40 becomes H level, the transistor 35 is turned on, and the actuator 38 is activated to open the inside/outside air switching door 4. Maximize the rotation angle θ. On the other hand, regardless of the output of the inverting circuit 46, the NOR circuit 44
Since the output of transistor 48 is at L level,
is off and the electromagnetic clutch 51 is not energized, so the compressor is not activated. That is, for example, if the vehicle is left in the hot sun and the inside air temperature is higher than the outside air temperature, 100% of the outside air is introduced, this causes the inside air to be expelled, and the inside air temperature drops to the outside temperature. At this time, the compressor is off and no cooling is performed. Therefore, the temperature can be lowered simply by introducing outside air, so that the power consumption of the compressor can be reduced. Next, when the inside air temperature Tr becomes lower than the outside air temperature Ta due to the outside air introduced, the output of the operational amplifier 40 becomes L level, and the output of the NOR circuit 44 becomes H level.
level, the compressor is driven and cooling is performed. On the other hand, in detail regarding the operational amplifier 12, when the number of passengers n is 4 and the switches S ₁ and S ₂ are on, the inputs A and B of the analog switch 11 are at L level,
The operation of the analog switch 11 is as shown in the following table, only switches a ₁ and a ₂ are turned on, resistors 16 and 20 act on the operational amplifier 12, and

[Table] When the number of occupants n is 3, only switches b ₁ and b ₂ are turned on, resistors 15 and 19 act, and the number of occupants n is 2.
In the case of , only switches c ₁ and c ₂ are turned on and resistors 14 and 18 act, and when the number of passengers n is 1, only switches d ₁ and d ₂ are turned on and resistors 13 and 17 act. . Therefore, when the inside air temperature Tr gradually becomes smaller than Ta and (room temperature set temperature Td - inside air temperature Tr) gradually increases, the output of the inside air sensor 25 gradually increases, and the operational amplifier 24
As shown in FIG. 4, the output V ₁ of the air conditioner normally increases gradually from -3 DEG C. during cooling operation, for example. Therefore, since this voltage V ₁ is supplied to the non-inverting input side of the operational amplifier 12, the output of the operational amplifier 12
As shown in Fig. 5, V ₂ slopes from -3 as the starting point, and at a certain value, the diode 21 turns on, so its output V ₂ becomes saturated, but the slope angle and the value of the saturation voltage depend on the effect. varies depending on the resistances 13 to 16 and the resistances 17 to 20,
For example, if there is one occupant (driver only), Td-Tr
As the voltage changes, the voltage V ₂ starts from Td-Tr=-3.
is the most gentle slope, then the voltage at Td-Tr=0
Saturation occurs at V ₁ . As a result, the temperature Tr becomes lower than Ta, and (Td-Tr)<-3, so in Fig. 6, Tr≧Td
If +3 is satisfied (section m), no matter how many people are on board, the output V ₂ is 0, as is clear from the characteristics shown in Figure 5, so the output of the operational amplifier 33 is 0, and the transistor 35 is turned off. , As a result, the actuator 38 does not operate, and the rotation angle θ of the inside/outside air switching door
becomes 0, outside air is not introduced, and only the compressor operates. By further lowering the inside air temperature Tr, Tr≦Td+3 is satisfied, and Tr>Td
In (section n), the output V ₂ gradually increases as shown in FIG. For this reason, if the output V ₃ of the variable resistor 10 for detecting air flow rate is kept constant, the output of the operational amplifier 33 will gradually increase, so the output of the transistor 35 will increase, and the actuator 38
is controlled, and the rotation angle θ of the inside/outside air switching door 4 gradually increases, and the rate of change in this rotation angle θ is the same, since the output V ₂ depends on the number of occupants as shown in FIG. It will depend on the number of passengers. That is, as the number of passengers increases, this rotation angle θ increases rapidly. Also, under the above conditions
In Tr≦Td (section 0), the output V ₂ is saturated, and this saturation level depends on the number of passengers, so the maximum value of the rotation angle θ is also set depending on this. For example, if the number of passengers increases, The maximum value of this rotation angle θ becomes large, and a large amount of outside air is introduced. That is, the amount of outside air introduced is adjusted according to the number of passengers. Next, the output V ₃ of the variable resistor 10 for air volume detection is supplied to the inverting input side of the operational amplifier 33.
This output V ₃ increases as the amount of air introduced into the outside air port 2 increases. Therefore, for example, when the rotation speed of the blower is set high and the amount of outside air introduced is large, the output of the operational amplifier 33 is reduced. Therefore, even if the number of passengers is large and the output V ₂ that increases the amount of outside air introduced is sent from the operational amplifier 12, if the amount of outside air introduced at that time is large,
Since the output V ₂ is corrected, a predetermined amount of outside air is introduced. As described above, according to this embodiment, when Tr>Ta (section 1), 100% outside air is introduced and the compressor is stopped, and when Tr<Ta, Tr>Td+3 (section m).
At Tr<Td+3, outside air is gradually introduced at Tr>Td (section n), and this introduction ratio depends on the number of passengers n and the current outside air intake air volume, and when Tr<Td In (section o), the amount of outside air introduced is saturated to a constant value, and this saturation value depends on the number of passengers and the amount of air introduced. For this reason, as shown in FIG. 6c, it is possible to obtain a power-saving portion P, and the amount of ventilation can be appropriately set, so that a feeling of comfort can be given to the occupant. In the present invention, the control characteristic f(n, v) of the rotation angle θ of the internal/external air switching door is set as shown in FIG. 7, with the number of occupants n and the fan speed V as factors, and the The rotation angle θ may be adjusted in accordance with this characteristic f(n, v) by storing it and detecting both factors. Note that the reason why the blower rotation speed V is used as a factor is to prevent, for example, the blower rotation speed from increasing and introducing more outside air than necessary. As explained above, according to the present invention, the outside air switching door is controlled according to the number of passengers, and the amount of outside air introduced is adjusted. Since there is no burden on the vehicle, power can be saved, and the required amount of ventilation is provided, providing a sense of comfort to the occupants.

[Brief explanation of the drawing]

1 and 2 are circuit diagrams and simplified configuration diagrams showing an embodiment of the vehicle air conditioner according to the present invention, and FIGS. 3 to 6 explain the operation of the vehicle air conditioner according to the present invention. FIG. 7 is a characteristic diagram showing another embodiment of the vehicle air conditioner according to the present invention. S ₁ , S ₂ ... switch, 2 ... outside air port, 3 ... inside air port, 4 ... inside and outside air switching door, 7 ... wind pressure door,
8... Rotation angle detection section, 11... Analog switch, 12, 24, 33, 40... Operational amplifier, 2
5... Inside air sensor, 38... Actuator, 4
1... Outside air sensor, 51... Electromagnetic clutch.

Claims (1)

[Claims] 1. An inside/outside air switching door that adjusts the amount of inside and outside air introduced, an actuator that drives the inside/outside air switching door, a number of occupants detection switch, an output of this number of occupants detection switch, a set temperature and an inside air temperature. a first control means that outputs a signal that changes with preset characteristics based on the difference; and a first control means that outputs a signal that changes with a preset characteristic based on the difference, and a first control means that operates the actuator based on the difference between the output of the detection section that detects the amount of introduced outside air and the output of the first upper air control means. a second control means for controlling and adjusting the opening degree of the inside/outside air switching door; What is claimed is: 1. An air conditioner for a vehicle, characterized in that the air conditioner is gradually increased to a predetermined value, and the rate of gradual increase and the above value are increased as the number of passengers increases.