JPS5940925A - Air conditioning control device of automobile - Google Patents

Abstract

PURPOSE:To prevent an outside-air temp. sensor from being affected by the external turbulence due to the preceeding car, by feeding the output of said outside-air temp. sensor into a target room-temp. arithmetic circuit as an air- conditioning control factor through a delay circuit in accordance with a the predetermined output of said outside-air temp. sensor. CONSTITUTION:The signals from a room-temp. sensor, an outside-air temp. sensor, and a solar radiation sensor 11 to 13, and a room temp. setting element 16, are inputted in an air-conditioning control system 15 actuated by a microcomputer. In said system, a target room temp. is operated in a circuit 22, the quantity of blow and the ratio of inside-outside air intake are controlled through drive circuits 23 and 24, the opening of mixed-air door is operated in a circuit 25, and the mixed-air door is controlled through a drive circuit 26. Here, if the output of the outside-air temp. sensor undergoes changes due to the external turbulence of air caused by the exhaust heat of a preceeding car, etc., and the detected value of changes 41 exceeds the preset value, a judging circuit 40 actuates a control circuit 20 to feed the output of the outside air temp. sensor 12 into the target room-temp. arithmetic circuit 22 through the delay circuit 21. Thereby the influence of the outside air turbulence can be prevented with the air conditioning control always maintained in a comfortable condition.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an air conditioning control device for an automobile, and more particularly to an air conditioning control device for an automobile that utilizes a microcomputer to air condition the interior of a vehicle in response to changes in outside temperature.

Conventionally, automobile air conditioning control devices have been fully automated by the introduction of microcomputers, and the air conditioning control elements include, for example, a vehicle interior temperature setting unit, a vehicle interior temperature sensor,
The output of an outside temperature sensor or the like is used, and various calculations are executed by a control program that uses these control elements as input data to control the air conditioning system.

By the way, the outside temperature sensor, which is used as an air conditioning control element in air conditioning control, detects the humidity outside the vehicle, and is an important part of determining the air conditioning control state inside the vehicle, so it is always accurate regardless of the situation outside the vehicle. It is necessary to obtain accurate temperature information.

However, since the outside temperature sensor is installed at a location where it is easy to detect the outside temperature, such as on the front bumper, for example, if the vehicle in question approaches a vehicle in front, the output of the outside temperature sensor may be affected by the exhaust heat from the muffler. may change independently of outside temperature.

Therefore, each time the vehicle receives a disturbance such as exhaust heat, the calculated data changes and the previously comfortable air conditioning condition changes, causing discomfort to the occupants. For this reason, measures have been taken to reduce the influence of external disturbances on external temperature sensors, such as installing appropriate 7-wires, but even so, it is difficult to avoid the influence of external disturbances, and on the contrary, the detection sensitivity is reduced. This invention was made by focusing on such conventional problems, and is an improvement to an automobile in which the outside air temperature sensor does not have any influence on the air conditioning control inside the vehicle even if the external temperature sensor is subjected to external disturbances. The purpose is to provide an air conditioning control device.

In order to achieve this object, the present invention includes a target room temperature calculation circuit that calculates a target room temperature in response to an output from an air conditioning control element such as an outside temperature sensor that detects the temperature outside the vehicle, and an output of the target room temperature calculation circuit. In an air conditioning control device for an automobile, which operates various air conditioning control means such as a cold/hot air mixing door installed in the air system A to air condition the interior of the vehicle, the output of the outside temperature sensor is adjusted according to a predetermined output of the outside temperature sensor. The control circuit is connected to a delay circuit that delays the temperature, and a control circuit that supplies the output of the delay circuit to the target room temperature calculation circuit as the output of the air conditioning control element.

The present invention will be explained below based on the drawings.

FIG. 1 to FIG. 4 are diagrams for explaining one embodiment of the present invention. First, to explain the configuration, reference numeral 1 in the figure is a single room of a car, and a ventilation duct 2 constituting the interior air conditioning system is attached to the passenger compartment 1 so as to communicate with each other. Outside air side Q1 for 2 people
Alternatively, an inside/outside air switching door 3 is provided that switches the intake of air from the indoor side R. Note that the indoor side R of the two inner and outer air intakes communicates with a ventilation hole IA formed in the passenger compartment 1. Further, in the ventilation duct 2, air blowers 7 and 4 are provided at predetermined intervals on the passenger compartment side of the inside/outside air switching door 3, that is, on the leeward side of the air blower, and an evaporator 5 is provided on the leeward side at a predetermined interval. A cold/hot air mixing door 6 is provided. A heater core 7 is provided at the other end of the ventilation duct 2 at a portion facing the passenger compartment 13- on the leeward side of the cold/hot air mixing door 6.

The inside/outside air switching door 3 can be opened and closed by, for example, a negative pressure drive type actuator 8 for the inside/outside air switching door. The rotation speed of the fan is freely controllable. In addition, the cold/hot air mixing door 6
can be opened and closed by, for example, a negative pressure drive type actuator 10 for adjusting the door opening degree.

Furthermore, a room temperature sensor 11 for detecting the temperature inside the vehicle interior is attached to an appropriate position in the vehicle interior 1, and an outside temperature sensor 12 for detecting the temperature of the outside air is attached to the outside of the vehicle body, for example, at the bumper portion. Further, a solar radiation sensor 13 is attached to, for example, a cowl or a rear grille portion of the vehicle body to obtain an output corresponding to the amount of solar radiation entering the vehicle interior. and,
Since each of the sensors 11, 12, and 13 is an analog output, it is connected to an analog-to-digital (A-D) converter 14, so that signal processing by a microcomputer 15 can be easily performed. Further, the microcomputer 15 is connected to a room temperature setting section 16 that generates a digital signal for setting the inside of the vehicle to a desired temperature.

The above-mentioned actuator 8 for switching between inside and outside air, the actuator 91 for controlling the amount of air, and the actuator 10 for adjusting the door opening are controlled by the microcomputer 15 according to a predetermined air conditioning control program for calculation processing. There is. Also, in Figure 1, the code 1
7 is a room temperature display section that displays the temperature set by the room temperature setting section 16, for example 5°C; 18 is an outside temperature display section that displays the temperature of the outside air detected by the outside temperature sensor 12, for example 35°C. , each display section 17, 18 is provided in the vehicle interior, for example, on an instrument panel.

Next, one embodiment of the microcomputer 15 will be described. The output of the outside air temperature sensor 12 which has passed through the A-D converter 14 is supplied to a determination circuit 40. This judgment circuit 4
0 indicates abnormal change detection circuit 41 and set value signal generation circuit 1
When the output change per unit time of the outside temperature sensor 12 exceeds a predetermined set value (for example, a change of 5 degrees Celsius in 30 seconds) in response to each output of the outside air temperature sensor 9, the control circuit 20 is activated. There is. Note that the control circuit 20 is supplied with the output of the outside air temperature sensor 12 directly or via a delay circuit 21 that temporally delays the output. The control circuit 20 is connected to a target room temperature calculation circuit 22 so that either the output of the outside temperature sensor 12 or its delayed output is supplied to the target room temperature calculation circuit 22.

The target room temperature calculation circuit 22 is configured so that in addition to being supplied with the output of the outside temperature sensor 12, the outputs of the above-mentioned solar radiation sensor 13 and room temperature setting section 16 are also supplied, and based on these outputs, the temperature inside the vehicle is determined. Target temperature Tg.

is now calculated. In other words, T2O(t>
-K+ Ts(t) + K2 Ta(t) + K
An operation based on the formula sZ(t) is performed. Here, Ts represents the set temperature in the room temperature setting section 16, Ta represents the outside air temperature, and 2 represents the amount of solar radiation, all of which are expressed as functions of time t. In addition,
K1. L.

K3 is a constant.

On the other hand, the output of the target room temperature calculation circuit 22 is supplied via the drive circuit 23 to the actuator 9 for controlling the air flow rate, and is also supplied via the drive circuit 24 to the actuator 8 for the inside/outside air switching door. Then, the drive circuit 23 compares the room temperature TR obtained from the room temperature sensor 11 with the degree Te6, and if the temperature difference exceeds a certain value (for example, ±5°C), the drive circuit 23 rotates the blower fan 4. The speed is fixed at a high speed Ht, and when the other constant value (for example, ±1°C) has not been reached, the rotational speed of the air blower 7 and 4 is reduced to a low speed. It operates in such a way that it is fixed in place. In addition, the drive circuit compares the indoor temperature TR and the target temperature Ts6, and when the temperature difference exceeds a certain value (for example, 5°C), attempts to introduce inside air, and conversely, when it is below that value, outside air is introduced. It operates to achieve this.

Furthermore, another output of the target room temperature calculation circuit 22 is supplied to the air-fuel mixture door opening degree calculation circuit 25.
In this case, the opening degree of the cold/hot air mixing door 6 is calculated based on the input from the room temperature sensor 11. That is, for example, when the temperature difference between the indoor temperature TR and the target temperature 7-Ta6 exceeds a certain value (for example, +10°C), the cold/hot air mixing door 6 is fully closed and only cold air is blown into the passenger compartment 1. The drive circuit 26 is operated in this manner to drive the door opening adjustment actuator 10.

Next, the operation of the air conditioning control device will be explained according to chart 70 of one air conditioning control program. For example, when an air conditioning control switch (not shown) is turned on while driving a car and the microcomputer 15 is powered on, the air conditioning control program starts calculating from step 27. Next, the routine moves to an initial setting routine 28, where the register circuit, counter circuit, latch circuit, etc. of the microcomputer 15 are set to the initial state necessary for execution of arithmetic processing, and preparations for reading input data from the outside temperature sensor 12, etc. are completed. do. Once this initial state is set, the determination circuit 40 and the control circuit 2
The routine then proceeds to an outside temperature change calculation routine 29 in which an operation such as 0 is performed. Based on the result of this calculation routine 29, the inside/outside air switching door 3
, the blower fan 4 , the cold/hot air mixing door 6 , etc. 8 - In order to drive the various air conditioning control means, the process moves to the various air conditioning control calculation routines 30 . And these calculation routines 2
9.30 is repeated at a predetermined cycle.

Next, details of the outside temperature change calculation routine 29 will be explained. In a process 31 following the initial setting routine 28, input data of the outside air temperature Ta (t) is taken out, and in a judgment 32 following this process 31, the current outside air temperature Ta (t) is the outside air temperature Ta (t-1
), it is determined whether or not there is an abnormal change. If the result of this determination is affirmatively YES, the process proceeds to step 33 and inputs the data of the outside air temperature Ta(t-1) instead of the data of the current outside air temperature Ta(t). This is based on the assumption that the temperature of the outside air generally does not change rapidly in an instant, and that if there is an abnormal change, it is because some external condition has occurred around the outside temperature sensor 12.

On the other hand, if the judgment result in judgment 32 is negative, the process advances to process 34, where the current outside air temperature 'l''a (t)
Continue inputting the data as is. Processing 33°34
After that, calculations are executed according to the various air conditioning control calculation routines 30 described above.

As explained above, according to the present invention, even if the outside temperature sensor attached to the vehicle body changes its output due to disturbances such as the exhaust heat of the preceding vehicle, a means is provided to remove the influence of the disturbances, so that the sensor is always comfortable. It is possible to maintain the interior of the automobile in a state where the air conditioning is properly controlled.

[Brief explanation of drawings]

Fig. 1 is a schematic configuration diagram of an air conditioning control device illustrating an embodiment of the present invention, Fig. 2 is a block diagram illustrating an electric circuit in the air conditioning control device of Fig. 1, and Fig. 3 operates the air conditioning control system. FIG. 4 is a more detailed flowchart of FIG. 3. 22...Target room temperature calculation circuit, 6...Cool/warm air mixing door, 12...Outside temperature sensor, 40...Judgment circuit, 21
...Delay circuit, addition...control circuit. 11- Figure 1 1/llj

Claims (1)

[Scope of Claims] A target room temperature calculation circuit that calculates a target room temperature in response to an output from an air conditioning control element such as an outside temperature sensor that detects the temperature outside the vehicle; In an automobile air conditioning control device that operates various air conditioning control means such as a cool/hot air mixing door installed to air condition the inside of a vehicle, 1. The change in the output per hour of the outside temperature sensor exceeds a predetermined set value. A determination circuit that obtains a predetermined output is connected to a delay circuit that delays the output of the outside temperature sensor according to a predetermined output of the determination circuit, and the output of the delay circuit is used as the output of the air conditioning control element. An air conditioning control device for an automobile, comprising a control circuit that supplies a target room temperature calculation circuit.