JPS6225523B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automotive air conditioning control method for reducing the cooling capacity of a refrigeration cycle in automotive air conditioning control.

Conventionally, in an automobile air conditioning control device (air conditioner), a compressor is connected to the vehicle engine, and the compressor compresses refrigerant to enable cooling and control the air conditioning. The compressor has a built-in electromagnetic clutch that disconnects and connects it to the engine, and when the outside temperature is lower than a predetermined temperature (approximately 12 degrees Celsius) or when the damper for mixing hot and cold air (A/M damper) There is a system that disconnects the compressor from the engine by turning off the electromagnetic clutch when the compressor is not required due to position, thereby saving unnecessary driving of the compressor.

However, if the windows are left open for longer than a predetermined time when air from outside the vehicle is introduced into the cabin for ventilation during normal driving, or when you want to obtain a comfortable feeling due to the introduction of outside air, the temperature inside the vehicle may increase. Even though changes occur due to the influence of the outside air temperature, the compressor continues to be driven to perform indoor air conditioning, and during this time a portion of the engine's power is wasted.

The present invention has been made in view of the above-mentioned problems, and determines that the amount of opening of the cabin due to the opening of the cabin opening/closing part has reached a predetermined level when the cabin air conditioning is stabilized due to the operation of the refrigeration cycle for cabin air conditioning. By lowering the cooling capacity of the refrigeration cycle from the previous cooling capacity at the time of determination, the power of the onboard power source is adjusted appropriately according to the air conditioning state at that time when the cabin opening/closing part is opened during cabin air conditioning. It is an object of the present invention to provide an air conditioning control method for an automobile that can save on air conditioning costs.

The present invention will be described below with reference to embodiments shown in the drawings. FIG. 1 is an overall configuration diagram showing an embodiment of an apparatus for carrying out the present invention.

In this Figure 1, 1 is an air duct that guides air for heating and cooling of the car's air conditioner, and an outside air intake port 1
Outside air is introduced through the air intake port 1b, and air inside the vehicle is circulated through the inside air intake port 1b. Reference numeral 2 denotes an inside/outside air switching damper, which manually switches between outside air introduction and inside air circulation.The outside air introduction state is shown by a solid line, and the inside air circulation state is shown by a broken line. 3 is a blower motor, which is connected to the outside air intake port 1a or the inside air intake port 1.
It sucks in air from b and blows it out. Reference numeral 4 denotes an evaporator through which the air blown by the blower motor 3 is cooled and passed, and is disposed across the air duct 1. 5 is a compressor that compresses and circulates the refrigerant, and is connected by a belt to the engine, which is the drive source of the vehicle, and is operated by the rotational power of the engine.
The refrigerant is compressed and sent to a condenser (not shown) to liquefy the high-pressure refrigerant, and through an expansion valve (not shown), the liquefied refrigerant is converted into a low-pressure, low-temperature liquid and sent to the evaporator 4, where it is removed from the blown air. It absorbs that heat and turns it into a low-pressure, low-temperature gas that is circulated. This compressor 5 has a built-in electromagnetic clutch for disconnecting and disconnecting from the engine.
When the electromagnetic clutch is energized, it becomes connected, and when the energization is cut off, it becomes disconnected. Reference numeral 6 denotes a heater core disposed within the air duct 1, through which engine cooling water is introduced and the blown air is heated by the heat thereof. 7 is the air mix damper.
The ratio of the amount of air introduced into the heater core 6 side and heated to the dehumidified and cooled air that has passed through the evaporator 4 is adjusted, and the temperature is adjusted by mixing the cold air of the cooling air and the warm air of the heated air. It's gushing inside. The opening degree of this air mix damper 7 is
The indoor temperature is automatically controlled to maintain the control target set temperature based on various information such as outside air temperature, set temperature, and damper opening feedback.

9 is a room temperature sensor that detects the temperature inside the vehicle interior 8 and generates a room temperature signal; 10 is an outside temperature sensor that detects the temperature of the outside air and generates an outside temperature signal; 11 is a temperature setting that determines the set temperature of the control target. The desired temperature is determined manually by the crew. Reference numeral 12 denotes a door switch, which also serves as an existing door switch and generates a door signal by detecting by OR logic that one or more of the doors of the automobile are opened. Reference numeral 13 denotes a window switch, which is installed in the window opening/closing operation section and generates a window signal by detecting, by OR logic, that one or more of the windows is opened to a predetermined degree or more. And this door switch 1
3. The door that opens and closes the passenger compartment with the window switch 12;
Detecting the open state of the window. Reference numeral 14 denotes an economy mode switch, which operates (on) or deactivates (off) the compressor 5 when the vehicle interior air conditioning is at a low level to reduce its operation, and generates an economy signal when it is turned on. . 15 is an A/D converter that converts an analog signal into a digital signal, which sequentially converts the room temperature signal from the room temperature sensor 9, the outside temperature signal from the outside temperature sensor 10, and the setting signal from the temperature setting device 11 into digital signals. It is something.

16 is a single-chip microcomputer that executes software digital calculation processing according to a predetermined air conditioning control program, and is connected to a several megahertz (MHz) crystal oscillator 17, and is powered by the on-board battery. A stabilized power supply circuit (not shown) that generates a stabilized voltage
The device is activated by receiving a stabilized voltage from the source. The microcomputer 16 calculates the ON and OFF conditions of the compressor 5, and outputs command signals for efficiently turning on and off the compressor 5, the rotational speed of the blower motor 3, and the air mix damper. It generates a command signal to adjust the opening degree of 7.

This microcomputer 16 includes a read-only memory (ROM) that stores an air conditioning control program that defines the calculation procedure for generating the above-mentioned command signal, and a read-only memory (ROM) that sequentially reads out the air conditioning control program in this ROM and performs the corresponding calculations. A central processing unit (CPU) that executes processing, a memory (RAM) that temporarily stores various data related to the arithmetic processing of this CPU and that can be read by the CPU, and a crystal oscillator 17 as described above. Made of a 1-chip large-scale integrated circuit (LSI), the main parts are a clock generator that generates reference clock pulses for various calculations, and an input/output (I/O) circuit that adjusts input and output of various signals. belongs to.

18 is a compressor drive circuit that controls on/off of the compressor 5, and controls the energization and cutoff of the electromagnetic clutch provided in the compressor 5 in response to an on/off command signal from the microcomputer 17 for power saving, and supplies power to the engine. The connection is controlled intermittently.

Next, the operation of the above configuration will be explained with reference to the calculation flowcharts of FIGS. 2 and 3.

2 is a calculation flowchart showing the overall calculation processing of the microcomputer 16 according to the air conditioning control program, and FIG. 3 is a calculation flowchart showing the detailed calculation processing of the compressor control calculation routine in FIG.

First, the arithmetic processing of this microcomputer 16 will be explained. Now, when a car equipped with this device is driven and the A/C switch (not shown) is turned on, the stabilized voltage is activated by the stabilized power supply circuit that supplies power via the ignition switch (not shown). Upon receiving the supply, the microcomputer 16 enters the operating state, and within several hundred milliseconds (m
The calculation process of the air conditioning control program is executed at the cycle of sec).

That is, the arithmetic processing of the air conditioning control program is started from the start step 100 in FIG. 2, and the program proceeds to the initial setting routine 200, where the registers, counters, latches, etc. in the microcomputer 16 are set to the initial states necessary for starting the arithmetic processing. do. This initial state setting operation includes an operation of setting timer data A to A=0, which will be described later. After this initial setting, the process proceeds to a compressor control calculation routine 300.

This compressor control calculation routine 300 performs calculations for turning on and off the compressor 5 based on signals from the room temperature sensor 9, outside temperature sensor 10, temperature setter 11, window switch 12, door switch 13, and economy mode switch 14. Executes processing and performs various temperature control calculation routines 40
Go to 0.

In this various control calculation routine 400, each signal from the room temperature sensor 9, the outside temperature sensor 10, the temperature setter 11, a cold air sensor (not shown) that detects the temperature after passing through the evaporator 4, and the air mix damper 7 are used. Based on each signal from an opening sensor (not shown) that detects the opening, the opening of the air mix damper 7 and the rotation speed of the blower motor 3 are calculated so that the temperature inside the vehicle approaches the set temperature, which is the control target. Based on the calculated results, a command signal is issued to each actuator (not shown) that drives the air mix damper 7 and the blower motor 3, and the process returns to the compressor control calculation routine 300. From now on, this compressor control calculation routine 3
The calculation process from 00 to various temperature control calculation routines 400 is repeated at a cycle of several hundred milliseconds.

Next, the overall operation of air conditioning control in various states will be explained.

First, by turning on the air conditioner switch, the microcomputer 16 to which a stabilized voltage is supplied from the stabilized power supply circuit becomes operational, and the second
The arithmetic processing starts from the start step 100 in the figure, proceeds to an initial setting routine 200, performs various initial settings including A=0 for timer data A, and then proceeds to a compressor control arithmetic routine 300.

In this compressor control calculation routine 300, the calculation process starts from the signal input step 301 in FIG.
The set temperature signals are sequentially inputted as digital signals via the A/D converter 15 and temporarily stored.
Below are those digital signals for room temperature Tr, outside temperature
Tam and set temperature Ts. Then, the process advances to the next outside temperature determination step 302, and the outside temperature Tam is 15°C.
It is determined whether or not the value is greater than or equal to the value. At this time, if the temperature of the outside air is high and cooling is necessary for the vehicle interior air conditioning, the determination becomes YES and the process proceeds to deviation calculation step 303. In this deviation calculation step 303, the deviation ΔT is calculated based on the room temperature Tr and the set temperature Ts using the formula ΔT=Tr−Ts. At this time, if the interior of the vehicle is not in an abnormally high temperature state, the value will be smaller than 5℃, and the deviation △T
The determination at the next deviation determination step 304, which determines whether or not is 5° C. or higher, is NO. At this point, when the windows and doors, which are the opening/closing parts of the vehicle interior, are closed for the purpose of air conditioning the vehicle interior, the determinations in the next window determination step 305 and door determination step 306 become NO.
Furthermore, if the economy mode switch 14 for reducing the operation of the compressor 5 is not turned on before performing this vehicle interior air conditioning, the next economy mode determination step 307 will be determined as NO.
become. Then, the process proceeds to the next timer data setting step 308, where the value of timer data A is set to 0, and the process proceeds to compressor on command step 309. In this compressor on command step 309, a command signal for turning on the compressor 5 is issued to the compressor drive circuit 18, one calculation process of the compressor control calculation routine 300 is completed, and the process proceeds to the various temperature control calculation routines 400. and,
In this various temperature control calculation routine 400, calculation processing for controlling the opening degree of the air mix damper 7 and the rotational speed of the blower motor 3 is executed, and the process returns to the compressor control calculation routine 300. Thereafter, by repeating the calculation process from the compressor control calculation routine 300 to the various temperature control calculation routines 400 at a cycle of several hundred milliseconds, the opening degree of the air mix damper 7 and the blower motor 3 can be adjusted while continuing the operation of the compressor 5. Appropriately controls the rotation speed of the vehicle to bring the temperature inside the vehicle closer to the set temperature.

Thereafter, when the window is opened to introduce air from outside the vehicle into the vehicle interior for ventilation during this air conditioning control, window determination step 3 in the above-mentioned iterative calculation is performed.
05, the window signal is generated from the window switch 12, so the determination is reversed from NO to YES. Then, economy mode judgment step 3
The process proceeds to step 10, where the determination becomes NO, and the process proceeds to addition step 311. In this addition step 311,
A constant “1” is added to the previous timer data A (A=A+1) and the next timer judgment step 31
Proceed to step 2. In this timer determination step 312, it is determined whether or not the value of timer data A is greater than or equal to the repetitive calculation circuit value for approximately 30 seconds, but since the window has just been opened, the determination is NO, and the compressor The calculation is changed to proceed to the ON command step 309.

Then, this compressor control calculation routine 3
When the value of timer data A, which is updated every time it reaches the addition step 311 at 00, reaches the number of repetitions of approximately 30 seconds, the judgment at the timer judgment step 312 is reversed from NO to YES, and the compressor off command step is started. Proceed to 313. In this compressor off command step 313, a command signal for turning off the compressor 5 is issued to the compressor drive circuit 18, and the compressor control calculation routine 30
One operation process of 0 is completed. Therefore, by repeating the calculation process of the compressor control calculation routine 300 along with the calculation processes of the various temperature control calculation routines 400 at a cycle of several hundreds of milliseconds, the operation of the compressor 5 is stopped as ventilation occurs by opening the window.

Then, when you close the window to stop ventilation,
The determination at window determination step 305 is reversed from YES to NO, and the calculation is changed to proceed to door determination step 306, economy mode determination step 307, timer data setting step 308, and compressor on command step 309. Therefore, by repeating the calculation process from the compressor control calculation routine 300 to the various temperature control calculation routines 400 at a cycle of several hundred milliseconds, the restored compressor 5 operates to lower the vehicle interior temperature, which is the control target. Bring the temperature close to the set temperature.

Further, when the economy mode switch 14 is turned on when the air conditioning in the vehicle interior is stabilized by the above-described iterative calculation, when the economy mode determination step 307 is reached, the determination is reversed from NO to YES, and the process proceeds to the maximum cooling determination step 314. In this maximum cooling determination step 314, various temperature control calculation routines 400
It is determined whether the opening degree of the air mix damper 7 calculated in is the maximum cooling opening degree (100%). If the indoor air conditioner still has surplus capacity, the determination will be NO and the process will proceed to operation rate calculation step 315. In this operation rate calculation step 315, the operation rate R due to on/off of the compressor 5 is calculated from the deviation ΔT and the outside temperature Tam using the following equation.

R=20△T+K _R (Tam−15) In this formula, the coefficient 20 is when the outside temperature Tam is 15℃.
When △T=5℃, R is 100%, △T=
It is a proportionality constant determined so that R is 0% at 0° C., and the coefficient K _R is a constant for correction with respect to the outside temperature Tam. Also, this operating rate R is 0%≦R≦100
It is set as %. Then, the process advances to the next duty calculation routine 316, and the operation rate calculation step 315
The on/off duty for a predetermined period of time is determined based on the repeated calculation time of this air conditioning control program for the operation rate R obtained in . Then, the process advances to the next ON condition determination step 317, and the duty calculation routine 3
It is determined whether the on-time condition determined in step 16 has been met, and the determination is made when the on-time condition has been met.
Become YES and command compressor on Step 3
The process proceeds to step 09, but if it is not an on-time condition, the determination becomes NO, and the process proceeds to off-condition determination step 318.
Proceed to. In this OFF condition determination step 318,
Similar to the on condition determination step 317 above, when the off time condition is met, the determination becomes YES and the process advances to the compressor off command step 313.
When the off-time condition is not met, the determination becomes NO and one calculation process of the compressor control calculation routine 300 is completed. Therefore, by repeating the calculation process from the compressor control calculation routine 300 to the various temperature control calculation routines 400 at a cycle of several hundred milliseconds, the opening degree of the air mix damper 7 can be adjusted appropriately while turning the compressor 5 on and off. The air conditioner inside the vehicle is adjusted accordingly.

In this state, when the window is opened for ventilation, when the window determination step 305 in the above-mentioned iterative calculation is reached, the determination is NO.
Then, the process advances to economy mode determination step 310, where the determination becomes YES, and the process advances to compressor off command step 313, where a compressor off command is issued, and one calculation process of the compressor control calculation routine 300 is completed. do. Therefore, when the window is opened in the economy mode, the operation of the compressor 5 is immediately stopped.

Further, in the above description, the on/off control of the compressor 5 was described when opening and closing the window, but it is clear that the same control as when opening and closing the window is performed when the door is opened and closed.

In the above embodiment, the cooling capacity of the refrigeration cycle is adjusted by turning on and off the compressor 5, but there is also a device that controls the capacity of the condenser in the refrigeration cycle as a variable cooling device that changes the cooling capacity. , a device that controls the cooling fan of the condenser, a device that controls the capacity or air volume of the evaporator 4, a device that controls the set bypass flow rate of the EPR, a device that controls the capacity of the compressor 5 or the number of its pistons, etc. may be used.

Further, although a door and a window are shown as the vehicle interior opening/closing part, a sunroof or a ventilation fan may also be used.

Furthermore, when the window signal from the window switch 12 that detects that the window is opened more than a predetermined opening degree and the generation of the window signal continues for 30 seconds or more, or when the window signal is generated in the economy mode, the vehicle interior is The operation of the compressor 5 is stopped when the amount of opening reaches a predetermined level, but in order to more accurately determine the amount of opening of the cabin, multiply the opening/closing area of each window by the elapsed time, and calculate the multiplied value. The operation of the compressor 5 may be stopped when the value exceeds a predetermined value.

Furthermore, the room temperature Tr and the set temperature are
The deviation △T of Ts is shown below 5℃, but the level judgment value of 5℃ may be 3℃, and the level judgment value is corrected by the outside temperature Tam etc. It's okay to be hot.

Furthermore, the above embodiment is applied to a microcomputer 1.
6 has been shown to be performed using software, but it may also be performed using hardware having an electronic circuit configuration.

As described above, in the present invention, when the cabin air conditioning is stable due to the operation of the refrigeration cycle, it is determined that the amount of opening of the cabin due to the opening of the cabin opening/closing part has reached a predetermined level, and at the time of this determination, the cooling of the refrigeration cycle is Since the cooling capacity is lower than the previous cooling capacity, it has the excellent effect of allowing the power of the on-board power source to be appropriately reduced depending on the air conditioning status at that time when the cabin opening/closing part is opened during cabin air conditioning. There is.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram showing one embodiment of a device implementing the present invention, FIG. 2 is a calculation flowchart showing the entire calculation process by the air conditioning control program of the microcomputer in FIG. 1, and FIG. 2 is a calculation flowchart showing detailed calculation processing of the compressor control calculation routine in FIG. 2. FIG. 2...Inside/outside air switching damper, 3...Blower motor, 4...Evaporator, 5...Compressor,
6... Heater core, 7... Air mix damper,
9...Room temperature sensor, 10...Outside temperature sensor, 11
... Temperature setting device, 12 ... Window switch, 13 ...
Door switch, 16...microcomputer,
18... Compressor drive circuit.

Claims (1)

[Scope of Claims] 1. An automotive air conditioning control method for controlling the air conditioning in a vehicle interior by adjusting the cooling capacity of a refrigeration cycle for indoor air conditioning of the vehicle, comprising: opening and closing the vehicle interior when the interior air conditioning is stabilized by the operation of the refrigeration cycle; 1. A method for controlling air conditioning for an automobile, comprising: determining that the amount of opening of the vehicle interior by opening the refrigeration cycle has reached a predetermined level; and upon this determination, reducing the cooling capacity of the refrigeration cycle from the previous cooling capacity.