JPH04244411A - Air conditioner for vehicle - Google Patents

Abstract

PURPOSE:To prevent cool wind from not blowing out due to the operation of a warm-up mechanism when the mode of a spit hole is changed to the heat mode when the maximum cooling condition is desired in summer. CONSTITUTION:Limiters 30 and 31, which play a role of a limit switch to detect the positions of a servo motor to drive the air mix damper near a heater core respectively, are provided in the servo motor so that warm-up control may not be performed even the mode of a spit hole is changed to the heat mode when a damper is located near a max. cool position.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle air conditioner having a warm-up function that blows air out through a heater core after it has been warmed up during winter.

0002

[Prior Art] As this type of vehicle air conditioner,
There is one equipped with a warm-up control means as shown in -233112. In a conventional device equipped with such a control means, a step of determining whether or not there is a command to blow out warm air from the heater outlet in the flowchart of the microcomputer in the control device, that is, whether it is in foot mode or not. is provided, and when YES, that is,
When foot mode is selected, it is assumed that warm-up control has been commanded, and the water temperature has reached a predetermined temperature (for example, 30
°C) or higher.

[0003]This is usually done by measuring the water temperature in the tank of the heater core. If it is determined that the water temperature has not risen sufficiently, the blower is turned off or set to a weak wind. Modern vehicle air conditioners, such as electric auto air conditioners, are used during times when maximum cooling capacity is required, such as in the summer.
Set the blower to auto and face mode (vent mode)
If you change the air outlet to foot mode (heat mode) while using the maximum cool condition, the warm-up function will activate, the blower air volume will decrease or it will turn off, and the cold air will no longer come out, causing the air conditioner to become less effective. becomes worse or does not work at all.

0004

Problems to be Solved by the Invention Originally, the warm-up function is required when hot air needs to be blown during the winter when the engine water temperature is low immediately after the engine is started. Therefore, it is an object of the present invention to provide a vehicle air conditioner to which a mechanism for canceling the warm-up function is added except in such cases.

[0005]

[Means for Solving the Problems] The air in the vehicle interior (1) is air-conditioned through an evaporator (6) and a heater core (7), and the state of heat exchange between the heater core and the air is adjusted around the heater core. A damper (8) is provided, and the temperature of the heater core is detected when the blowing direction is selected to be a foot mode so that the air after passing through the heater core is blown in the direction of the foot portion of the occupant in the vehicle interior. The device includes a warm-up control means for blowing out the air after the air is warmed up, including a limiter (30, 31) for detecting the opening degree of the damper (8) from the maximum cool, and a limiter (30, 31) for detecting the opening degree of the damper (8), A blower (5) that determines the air volume, a water temperature sensor (46) that detects the temperature of the heater core, a foot mode detection means (51) that detects whether the air blowing direction is the foot mode, and a necessary cooling temperature. A control device (13) is provided which calculates and controls the supply of refrigerant to the evaporator and the supply of hot water to the heater core, as well as the opening degree of the damper and the amount of air blown by the blower. The limiter (30
, 31) is detected to be within a predetermined range from Max Cool, the operation of the warm-up control means is interrupted, and the air enters the vehicle interior as cold air in the foot mode state. When the air is being blown out, the blower blows the air according to the required cooling temperature.

[0006]

[Operation] In the basic configuration of the present invention, a warm-up control means is provided in the control device, which is convenient in winter because cold air is no longer blown out.
In the summer, when trying to send cold air to the feet in the foot mode, the warm-up control means is activated and the cold air is reduced to a weaker level or does not come out at all.

However, in the present invention, when the signal from the limiter is within a predetermined range from the maximum coolant, that is, when the signal from the limiter is within a predetermined range from the position where the damper attempts to send air into the vehicle interior without being heated by the heater core as much as possible, If it is obvious that cold air is being blown into the vehicle interior, the operation of the warm-up control means is interrupted. Therefore, the blower is not weakened (including stopped) and blows air according to the required cooling temperature as in normal use.

[0008]

[Effects of the Invention] As described above, in the present invention, the warm-up control means itself can be temporarily interrupted without major changes, so existing ones can be easily modified and manufacturing is easy. A vehicle air conditioner with good performance can be obtained.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 2 is a schematic diagram of an air conditioner for an automobile according to an embodiment of the present invention. A ventilation duct 2 is arranged in the front part of the vehicle interior 1, and inside the ventilation duct 2, there is an inside/outside air switching damper 4 that changes the intake ratio of inside air and outside air in order from the intake port 3, and an amount of air taken into the vehicle interior 1. It has a blower 5, an evaporator 6, and a heater core 7.

Reference numerals 8a and 8b are dampers (referred to as air mix dampers) near the heater core 7 according to the present invention, and an air mix section (behind the heater) 9 which determines the temperature of the air blown out depending on the opening degree of the damper 8. is forming. Also,
The air outlets to the vehicle interior 1 are equipped with a defroster air outlet 10a, a vent air outlet 10b, and a foot heater air outlet 10c.The mode in which air flows through the heater air outlet 10c is called a foot mode (also referred to as a heater mode). to be called.

[0011] Reference numeral 11 denotes an outlet switching damper, which switches between the defroster outlet 10a, the vent outlet 10b, and the heater outlet 10c.The switch button 51 in the control panel determines which position it is switched to.
A foot mode detecting means consisting of a foot mode detecting means detects the foot mode, and inputs this detection signal to the control device 13. Air mix damper 8
are arranged separately above and below the heater core 7, but are operated in conjunction with a single servo motor 14. Inside the servo motor 14 is a potentiometer that generates a signal indicating the position of the damper 8, as shown in FIG. Resistor 20 for
and a conductive piece 21, and a conductive piece group 22 forming a limit switch is provided on the servo motor case 23 side, while brushes 25, 26 are provided on the rotor 24, which rotates in synchronization with the output shaft of the servo motor. is provided. Note that the arrangement up to this point is a well-known arrangement within the servo motor.

Furthermore, the present invention includes a second limit switch, which constitutes a limiter of the present invention, which detects whether or not the air mix damper 8 is within a predetermined range from the maximum cooled state (solid line state in FIG. 2). Conductive pieces 30, 31 and a brush 32 are provided, and the second limit switches 30, 31, 32 form the limiter of the present invention.

When the current is within a predetermined range from the above-mentioned Max Cool, that is, within the angle θ shown in FIG. 3, there is no conduction between the output terminals 33 and 34. Therefore, in the foot mode, that is, when the air is blown out from the heater outlet 10c and within the angle θ described above, the positive potential is applied to the fixed contact piece 12a of the blowout mode detection sensor in the actuator 12. 12b and the movable contact piece 12c, but there is no continuity between the conductive pieces 30 and 31,
A positive potential (warm-up command) is not applied to the control device 13 via the output terminal 34.

A compressor 40 for supplying refrigerant is connected to the evaporator 6, and engine cooling water is circulated to the heater core 7 via a water valve 41. 42 is an inside air sensor, 43 is a solar radiation sensor, and 44 is an outside air sensor that detects outside temperature.

Further, 45 is an evaporator outlet temperature sensor, and 46 is a sensor for detecting the water temperature in the tank portion of the heater core 7. Next, a control panel provided in the vehicle interior 1 is provided with a temperature setting device 50 for setting the vehicle interior temperature to a desired temperature and a switch button 51 for instructing switching of the air outlet. Then, the control device 13 grasps which of the switch buttons 51 is pressed, and switches the outlet switching damper 11 via the actuator 12.

The electronic control unit 13 performs calculations based on the detection signals of the sensors and the signals of the switches described above, and controls the various actuators described above by outputting command signals. The electronic control device 13 includes a CPU, ROM, and RAM.
It consists of a well-known microcomputer equipped with input/output interfaces, etc. The control operations by this air conditioner are processed according to the control program stored in the ROM, and include switching the air volume by the blower 5 and controlling the air mix damper based on various temperature data detection signals, sensor detection values, etc. 8 to automatically control the room temperature.

The flow of processing in the microcomputer within the control device 13 is substantially the same as the conventional one, and only the differences will be explained. FIG. 4 shows a part of the flowchart, and first, in step 120, it is determined whether or not a warm-up control command has been output. A determination is made as to whether there is no electrical continuity between 30 and 31.

If it is determined in this step 120 that warm-up control has not been commanded, that is, that the positive signal is not coming to the control circuit from the terminal 34 in FIG. Control is executed. On the other hand, when it is determined in step 120 whether or not a warm-up command has been received from the limiters 30 and 31 in the servo motor 14, if a warm-up command has been received, that is, the terminal 34 has a positive potential. When the damper 8 is located outside the predetermined rotation range (θ) from the maximum cooling, the process moves to step 123 and it is determined whether the temperature Th measured by the sensor 46 is equal to or higher than the predetermined temperature Tw. A determination is made as to whether or not the water temperature in the tank section 7 has been warmed to a predetermined temperature Tw or higher.

If it is determined that the temperature Th is less than or equal to Tw, that is, if it is determined that the blown air is not sufficiently warmed, the process proceeds to step 124 and the blower 5 is turned off to produce a weak breeze or is turned off. Set to . On the other hand, when the warm-up command has not come from the servo motor 14, the determination in step 120 is NO, the blower 5 does not have a weak air flow, and normal air conditioning control in step 121 is performed.

In this normal air conditioning control, the control device calculates the required cooling temperature (TAO) from various sensors, and the air volume of the blower is controlled accordingly, as is well known. In addition, as a second embodiment, the second limit switches 30, 31, and 32 in the servo motor 14 may be configured with a second potentiometer, that is, a combination of a conductive piece, a resistor, and a brush.

In this case, a determination circuit for canceling the warm-up signal based on the potentiometer voltage is added to the control circuit, so that the warm-up can be canceled when the potentiometer voltage exceeds a certain value. Next, a third embodiment will be explained. In this embodiment, the microswitch 6 is shown in FIG.
0 is used to mechanically turn off the warm-up signal and cancel the warm-up. In FIG. 5, a micro switch 6 with an ON-OFF function is located on the cool side of a control lever 61 of a temperature setting device 50 that adjusts the set temperature, which is a component in the control panel.
A certain point on the cool side (a
) can cancel the warm-up signal from max cool.

Furthermore, by placing the microswitch in the vicinity of the air mix damper 8 that adjusts the amount of air passing through the heater core 7 in FIG. 2, the warm-up signal can be canceled from a certain point on the cool side to the maximum cool. You may also do so.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of the present invention.

FIG. 2 is an overall configuration diagram showing an embodiment of the present invention.

FIG. 3 is a schematic wiring diagram showing the relationship between the inside of the servo motor, the damper opening sensor, and the control device in the embodiment.

FIG. 4 is a flowchart showing part of the processing of the control device used in the embodiment.

FIG. 5 is a schematic diagram of a temperature setting device used in a second embodiment of the present invention.

[Explanation of symbols]

6 Evaporator 7 Heater core 1 Vehicle interior 8 Damper 124 Step 5 forming warm-up control means
Blower 12 Blow mode detection sensor 13 Control device 30, 31 Limiter

Claims (1)

[Claims] 1. A damper (8) that air-conditions the air in the vehicle interior (1) via an evaporator (6) and a heater core (7), and adjusts a heat exchange state between the heater core and the air around the heater core. When the air blowing direction after passing through the heater core is set to foot mode so that the air blows out in the direction of the foot portion of the occupant in the vehicle interior, the temperature of the heater core is detected and the air is blown out. A limiter (30,
31), a blower (5) that determines the amount of air blown, a water temperature sensor (46) that detects the temperature of the heater core, and a foot mode detection means (51) that detects whether the air blowing direction is in the foot mode or not. ), and a control device (
13), having the warm-up control means in the control device, and when detecting that the signal from the limiter (30, 31) is within a predetermined range from the max cool, the warm-up When the operation of the control means is interrupted and the air is being blown into the vehicle interior as cold air in the foot mode, the blower blows the air according to the required cooling temperature. Vehicle air conditioner.