JPS636365B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an air conditioner for an automobile, and particularly to a reheat type automobile air conditioner that is equipped with a heater core and adjusts the amount of air blown and the amount of heating. The present invention relates to an air conditioner for an automobile that can sufficiently increase the amount of air blown during maximum cooling when the amount of heating is at the minimum level.

[Prior Art] A reheat type air conditioner is known as an automotive air conditioner, and this type of air conditioner generally includes a heater core in a ventilation duct that heats air cooled by an evaporator, and a heater core that heats air cooled by an evaporator. Air conditioning can be performed over a wide range by adjusting the air volume and heating amount.

[Problems to be Solved by the Invention] However, since this type of air conditioner has a structure in which the entire air after cooling passes through the heater core, the heater core acts as ventilation resistance, and therefore it is difficult to sufficiently increase the air volume during maximum cooling. The problem was that it was difficult to do so.

[Means for Solving the Problems] The present invention aims to solve the above problems by increasing the amount of air blown during maximum cooling,
An object of the present invention is to provide an air conditioner for an automobile that can sufficiently increase cooling capacity.

The configuration of the present invention for this purpose will be explained based on FIG. 4. FIG. 4 is a block diagram showing the basic concept of the present invention. As shown in FIG. 4, the present invention provides a reheat type automobile air conditioner equipped with a cooler b, a heater c, and a blower d disposed in a ventilation duct a, in which the heating amount of the heater c is adjusted. a heating amount adjusting means e for adjusting the amount of air blown by the blower d; a bypass passage g provided in the ventilation duct a to bypass the heater c; Bypass switch h that opens and closes
and condition determination means i for determining whether the air flow rate of the blower d is at the maximum level and determining whether the heating amount of the heater c is at the minimum level.
and bypass switch driving means j for opening the bypass switch h when the condition determining means i determines that the air flow is at the maximum level and the heating amount is at the minimum level. The gist of this article is an air conditioner for automobiles characterized by the following features.

[Function] Next, the function of the present invention will be explained based on FIG. 4.

In the case of normal operation, cooling is performed by a cooler b disposed in the ventilation duct a, heating is performed by a heater c, and ventilation is performed by an air blower d. The heater c is a heating amount adjusting means e.
At the same time, the blower d
A predetermined amount of air is blown by the air blown amount adjusting means f.

However, when the condition determining means i determines that the air flow rate is at the maximum level and the heating amount is at the minimum level, the bypass switch driving means j is determined based on the determination by the condition determining means i. Open bypass switch h.

As a result, a bypass passage g provided by bypassing the heater c inside the ventilation duct a is opened, and the air blown by the blower d comes to pass through the bypass passage g. The technical problems of the present invention are solved as described above.

[Example] Next, an example of the present invention will be described in detail based on the drawings.

FIG. 1 shows a system configuration diagram of a first embodiment of the present invention.

In Fig. 1, 1 is the main body of the air conditioner, which has the main parts as shown, 2 is the ventilation duct,
3 is a blower motor, 4 is an evaporator installed downstream of the blower motor 3, and 5 is an evaporator 4
6 is a bypass passage provided above the heater core 5 , 7 is a bypass damper that opens and closes the bypass passage 6 , 8 is a vent outlet (upper outlet), 9 is a vent outlet 8 10 is a heat outlet (lower outlet), 11 is a heat damper that opens and closes the heat outlet 10, and 12 is an automobile engine.

The blower motor 3 blows air sucked into the ventilation duct 2 through the air suction port by an inside air damper and an outside air damper (not shown) toward the blower ports 8 and 10, and is driven by a blower drive circuit 20, which will be described later. Change the air volume level stepwise or steplessly.

The evaporator 4 forms a refrigeration cycle together with a compressor (not shown), an expansion valve, a liquid receiver, and a condenser, and cools the air blown by the blower motor 3. The compressor is driven by the engine 12, and the driving force from the engine is transmitted or cut off in response to turning on and off of an electromagnetic clutch interposed between the compressor and the engine 12.

The heater core 5 heats the air cooled by the evaporator 4, and the water valve 1
The heating amount is adjusted according to the flow rate of the engine cooling water (hot water) of the engine 12 that is bypassed by the engine 3. Here, the opening degree of the water valve 13 is adjusted based on a water valve driving signal to be described later, and as the valve opening degree increases, the bypass flow rate, that is, the hot water flow rate supplied to the heater core 5 is increased, and the heating by the heater core 5 is increased. Increase quantity.

The bypass passage 6 allows a part of the air cooled by the evaporator 4 to pass downstream without being heated by the heater core 5.

Further, in FIG. 1, 14 is a group of detectors for detecting the operating conditions of the air conditioner main body 1,
An inside air sensor that detects the temperature inside the vehicle, an outside air sensor that detects the temperature outside the vehicle, a solar radiation sensor that detects the amount of solar radiation, an after-evaporation sensor that detects the temperature of the air after it has been cooled by the evaporator 4, and a temperature of the cooling water of the engine 12. 15 is a potentiometer that detects the opening degree of the water valve 13. Reference numeral 16 denotes a control panel, and the control panel 16 includes, as an input section, a room temperature setting device for specifying the target temperature in the vehicle interior, an air volume setting device for specifying the volume of the blown air, and a blowing mode and a blowing mode. It is equipped with a blow-out mode switch and a blow-in mode switch for controlling air conditioning, an automatic control switch for specifying automatic air conditioning control, etc., as well as a set temperature display for displaying the target temperature inside the vehicle as an output section, and various types of Equipped with a lamp indicator etc. to indicate the operating mode.

17 is an input/output circuit, which includes an A/D converter, a multiplexer, etc., and converts signals from the input section of the detector group 14, potentiometer 15, and control panel 16 into signals suitable for processing by the microcomputer 18. , held, etc., and sent to the microcomputer 18, and outputs a control signal, which is a processing result by the microcomputer 18, to the output section of the control panel 16 and various drive circuits to be described later.

Reference numeral 18 represents a microcomputer, which is composed of a one-chip LSI, is activated by a constant voltage from a stabilized power supply circuit connected to an on-board battery (not shown), and generates several megahertz crystal oscillations according to a preset air conditioning control program. Arithmetic processing is performed in synchronization with the clock signal from the child 19. The internal configuration of the microcomputer 18 is a known one.
Consists of RAM, ROM, CPU, I/O circuit section, etc.

20 to 25 represent actuator drive circuits into which output signals from the microcomputer 18 are input. That is, 20 controls the blower motor 3 according to the blower drive control signal from the microcomputer 18.
This is a well-known blower drive circuit that uses a register to change the voltage applied to the motor in steps, or uses a transistor or the like to change the voltage applied to the motor in a stepless manner. 21 is a water valve driving circuit which amplifies the power of the valve opening signal from the microcomputer 18 and supplies it to the water valve driving section 26. Reference numerals 22, 23, and 24 are a heat damper drive circuit, a vent damper drive circuit, and a bypass damper drive circuit, respectively, which amplify the power of the damper opening/closing signal from the microcomputer 18 to drive the heat damper drive section 27, vent damper drive section 28, and bypass damper drive circuit. Part 29
supply to. Reference numeral 25 denotes a drive circuit for driving other air conditioning actuators, such as a compressor electromagnetic clutch and an inlet switching damper, which amplifies the power of the control signal from the microcomputer 18 and supplies it to each actuator. Reference numeral 26 represents a water valve drive unit that adjusts the valve opening degree of the water valve 13, and the water valve drive unit 26 includes a diaphragm having an atmosphere communication port and a negative pressure communication port, and communication between the diaphragm chamber and the atmosphere side.
It is equipped with two electromagnetic valves that respectively turn on and off communication between the diaphragm chamber and the negative pressure side of the engine, or it is equipped with a motor. 2
7, 28, 29 are heater dampers 11,
These are a heater damper drive section, a vent damper drive section, and a bypass damper drive section that open and close the vent damper 9 and the bypass damper 7, and are each configured similarly to the water valve drive section 26 described above.

Next, the main processing of the microcomputer 18 will be explained with reference to the flowchart shown in FIG. 2, which schematically represents the main parts of the air conditioning control program.

When a switch (not shown) is turned on and the microcomputer 18 becomes operational, the microcomputer 18 performs initialization and the like, and then shifts to this flowchart.

First, step 100 is executed, and the detector group 14,
Potentiometer 15 and control panel 1
Various signals are inputted from the input section 6 via the input circuit 17 and stored in a predetermined area on the RAM.

Next, execute step 101 and repeat step 1 above.
00, the set temperature data, vehicle interior temperature data, vehicle exterior temperature data, and solar radiation data are read from the RAM where the input data is stored, and are calculated using the predetermined calculation formula: TAO=K _set ×T _set −K _R ×TR−K _AM ×TAM−K _S ×ST+C (However, TAO, T _set , TR, TAM, and ST are the required blowout temperature, set temperature, vehicle interior temperature, vehicle exterior temperature, and solar radiation amount, respectively, and K _set , K _R , _KAM ,
K _S and C are each predetermined constants. )
Calculate the required blowout temperature.

Also, the valve opening of the water valve 13 necessary to obtain the necessary blowout temperature, that is, the necessary water valve opening (for example, 0% is MAX COOL, 100% is MAX
Compatible with HOT. ) is calculated. This required water valve opening degree is determined by experimenting in advance to determine the relationship between the valve opening degree and the blowout temperature, storing the relationship in the ROM as a table or formula, and calculating using the table or formula. .

Next, execute step 102 and repeat step 1 above.
The amount of air blown by the blower motor 3 is determined based on the control mode data from the input section of the control panel 16 stored in the RAM by executing 00. That is, when the airflow rate is selected by the airflow rate selection switch on the control panel 16, an airflow control signal corresponding to the selected airflow rate is output to the blower drive circuit 20, while the control panel 1
When the automatic control mode is selected by the automatic control switch above, the air volume pattern is set in advance according to the required blowing temperature. When the air volume becomes lower, the air volume is automatically determined based on a pattern in which the air volume level increases as the deviation from room temperature increases, and a corresponding air volume control signal is output to the blower drive circuit 20.

Next, execute step 103 and repeat step 1 above.
It is determined whether the required water valve opening degree data calculated by the 01 execution corresponds to 0%, that is, MAX COOL. In other words, it is determined whether the amount of heating is at a minimum level, that is, whether maximum cooling is required.

If it is determined that maximum cooling is required, then step 104 is executed, and the step 102 described above is executed.
It is determined whether the air flow rate determined by the execution is Ex-Hi, that is, the maximum level.

If it is determined that the air flow rate is at the maximum level, then step 105 is executed, a bypass damper open command signal instructing that the bypass damper 7 should be opened is outputted to the bypass damper drive circuit 24, and this program is executed. The process ends.

On the other hand, if maximum cooling is not requested, or if maximum cooling is requested but the maximum air flow rate is not selected, step 106 is executed;
A bypass damper close command signal instructing that the bypass damper 7 should be closed is output to the bypass damper drive circuit 24, and the processing of this program is ended.

It goes without saying that after this program is finished, known air conditioning control processes such as compressor on/off control, suction/outlet switching control, etc. are performed.

In the first embodiment, the ventilation duct a is connected to the ventilation duct 2, the cooler b is connected to the evaporator 4,
The heater c is connected to the heater core 5, the blower d is connected to the blower motor 3, and the heating amount adjusting means e is connected to the engine 12, the water valve 13, and the water valve drive circuit 21.
and processes 100 and 10 executed by the water valve drive unit 26 and the microcomputer 18.
1, the air flow rate adjusting means f is connected to the processes 100 and 102 executed by the blower drive circuit 20 and the microcomputer 18, the bypass passage g is connected to the bypass passage 6, and the bypass switch h is connected to the bypass damper 7.
In this case, the condition determining means i is a microcomputer 18.
In the processes 103 and 104 executed by the bypass switch driving means j, the bypass damper driving circuit 2
4 and processing 105 executed by the bypass damper drive unit 29 and the microcomputer 18, respectively.

In the first embodiment, when maximum cooling and maximum air volume are required, the bypass damper 7
is maintained in the open state, otherwise the bypass damper 7 is maintained in the closed state.

Therefore, at maximum cooling and maximum air volume, the bypass passage 6 is opened, so the evaporator 4
The air cooled by this is sent to the outlet side through the bypass passage 6 which has almost no ventilation resistance, resulting in an advantage that the amount of air to be blown out is increased.

Next, a second embodiment of the present invention will be explained based on FIG.

FIG. 3 is a diagram schematically showing the main body of an air conditioner according to a second embodiment of the present invention.

In FIG. 3, reference numeral 1' represents the main body of the air conditioner in this embodiment, which is provided with a dedicated duct 30 that connects the bypass passage 6' directly to the vent outlet 8. Others, codes 2, 3, 4, 5, 7,
8, 9, 10, and 11 represent the same elements as the same reference numerals in FIG. 1, respectively.

The other components in this embodiment are the same as those in FIG. 1, and the processing operations are the same as in the first embodiment described above with reference to FIG.

In the second embodiment, the ventilation duct a is connected to the ventilation duct 2, the cooler b is connected to the evaporator 4,
The heater c is connected to the heater core 5, the blower d is connected to the blower motor 3, and the heating amount adjusting means e is connected to the engine 12, the water valve 13, and the water valve drive circuit 21.
and processes 100 and 10 executed by the water valve drive section 26 and the microcomputer 18.
1, the air flow rate adjusting means f is connected to the processes 100 and 102 executed by the blower drive circuit 20 and the microcomputer 18, the bypass passage g is connected to the bypass passage 6' and the dedicated duct 30, and the bypass switch h is connected to the bypass damper 7. , the condition determining means i is a process 103 executed by the microcomputer 18,
At 104, the bypass switch driving means j includes a bypass damper driving circuit 24 and a bypass damper driving section 29.
and processing 105 executed by the microcomputer 18, respectively.

The second embodiment also provides the same effects as the first embodiment described above.

[Effects of the Invention] As detailed above, the present invention provides a reheat type automobile air conditioner that includes a cooler, a heater, and a blower disposed in a ventilation duct and adjusts the amount of air blown and the amount of heating. A bypass passage bypassing the heater is provided, and a bypass switch is provided to open and close the bypass passage, and when the air flow rate is at the maximum level and the heating amount is at the minimum level, the bypass switch is opened. The above-mentioned bypass passage is opened when the bypass passage is opened.

Therefore, according to the present invention, it is possible to sufficiently increase the amount of air blown at the maximum cooling time and the maximum air volume, thereby improving the cooling capacity and making it possible to rapidly cool the vehicle interior.

[Brief explanation of the drawing]

FIG. 1 is a system configuration diagram of the first embodiment, FIG. 2 is a flowchart for explaining processing operations executed by a microcomputer, FIG. 3 is a configuration diagram of main parts in the second embodiment, and FIG. 4 1 and 2 respectively show configuration diagrams illustrating the basic concept of the present invention. a... Ventilation duct, b... Cooler, c... Heater, d... Blower, e... Heating amount adjustment means, f...
...Blow volume adjustment means, g...Bypass passage, h...
Bypass switch, i... Condition determining means, j... Bypass switch driving means, 1... Air conditioner main body, 2
... Ventilation duct, 3... Blower motor, 4... Evaporator, 5... Heater core, 6, 6'... Bypass passage, 7... Bypass damper, 8... Vent outlet (upper outlet), 9... vent damper,
10... Heat outlet (lower outlet), 11...
Heat damper, 13...Water valve, 14...
...Detector group, 15... Potentiometer, 16...
...Control panel, 18...Microcomputer, 20...Blower drive circuit, 21...Water valve drive circuit, 22...Heat damper drive circuit, 23...Vent damper drive circuit, 24...
Bypass damper drive circuit, 26... Water valve drive section, 27... Heat damper drive section, 28...
...Vent damper drive section, 29...Bypass damper drive section.

Claims (1)

[Scope of Claims] 1. A reheat type automobile air conditioner equipped with a cooler, a heater, and a blower arranged in a ventilation duct, comprising: heating amount adjusting means for adjusting the heating amount of the heater; and the blower. a bypass passage provided in the ventilation duct to bypass the heater; a bypass switch for opening and closing the bypass passage; and a bypass switch for opening and closing the bypass passage; a condition determining means for determining whether the amount of air blown is at the maximum level and the amount of heating is at the minimum level by the condition determining means; An air conditioner for an automobile, comprising: bypass switch driving means that opens the bypass switch when the determination is made.