JPH0523964B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vehicle air conditioner, and particularly to heating activation control.

[Conventional technology]

Conventionally, as shown in FIG. 2, a vehicle air conditioner includes an inside/outside air switching door 2 provided in a duct 1, a blower 3, a cooler 4, an air mix door 5,
It includes a heater 6, a mode switching door 7, a defrost outlet 8, a face outlet 9, and a foot outlet 10. The cooler 4 includes a compressor 11,
The condenser 12, receiver tie 13, and expansion valve 14 constitute a cooling cycle. The rotational force of the engine 15 is transmitted to the compressor 11 via a magnetic clutch 16.

17 is an A/D converter, which detects the temperature Tr detected by the inside air sensor 18 that detects the temperature inside the vehicle, the opening degree θ of the air mix door 5 detected by the position detection potentiometer 19, and the amount of solar radiation Ts detected by the solar radiation sensor 20. , the outside air temperature Ta detected by the outside air temperature sensor 21, the duct internal temperature Tm detected by the mode sensor 22, the set temperature Td output from the temperature setting device 23, and the water temperature switch 45.
The signal Tw outputted from the controller 24 is converted into each digital signal and outputted to the control section 24.

The control unit 24 is composed of, for example, a microcomputer, and controls the switching circuit 25 and the actuator 2.
6, a compressor control means 29 that controls the magnetic clutch 16 via a drive circuit 28, and a blower 3 via a drive circuit 30.
a blower control means 31 for controlling the
2. Air mix door control means 34 that controls the air mix door 5 via the actuator 33
, a mode switching door control means 37 that controls the mode switching door 7 via a switching circuit 35 and an actuator 36, and each control means 27, 29, 31 that calculates each data Tr, Ts, Ta, Tm, and Td. , 34 and 37, respectively. 3
9 is a manual switch for controlling the blower.

The compressor control means 29 controls the temperature inside the duct.
When Tm decreased to a temperature level (stored in the setting device 41) slightly higher than the freezing temperature of the cooler 4, the compressor 11 was turned off, and the temperature rose to a level higher than the above level by the hysteresis width (memorized in the setting device 40). The compressor 11 is sometimes turned on to keep the temperature of the cooler 4 constant.

Actuator 50 for air mix door control
As shown in FIGS. 3a and 3b, the rotational force of the motor 56 is transmitted to and controlled by the air mix door 5 via the intermediate gear 57, output gear 51, and output shaft 55. Here, a movable contact 52 is provided on the output gear 51,
The contact 5 is mounted on the board 53 facing the output gear 51.
2 is provided with a fixed contact 54 in sliding contact with the output gear 51.
The speed of the blower 3 is changed by changing the input voltage of the drive circuit 30 by changing the connection relationship between the movable contact 52 and the fixed contact 54 due to the rotation of the fan (Japanese Patent Laid-Open No. 58-209609).

According to this, the speed is switched according to the opening degree θ of the air mix door as shown in the characteristics l and m in FIG. , no separate blower control means 31 is required.

[Problem that the invention seeks to solve]

However, conventional vehicle air conditioners
As disclosed in Japanese Patent Application Laid-Open No. 58-209609, as shown in FIGS. 3a and 3b, a sliding contact 52 interlocking with the output gear 51 of the actuator 50 that drives the air mix door is arranged opposite to the output gear 51. The speed of the blower is controlled by a changeover switch, which is the speed setting means F, and is made up of fixed contacts 54 (common, HI, LO, and MID) arranged on the board 53. When the vehicle air conditioner is started when heating needs to be started, the air mix door is set to full hot mode _M1 by the output of the air mix door control means 34, and the blower 3 is set to high speed as shown in _M1 in FIG. 3c. Since it is set, it is driven at high speed. As a result, cold air was suddenly blown out, resulting in poor feeling, and the internal contacts of the blower motor were likely to deteriorate due to the large current, and there was also a risk that the fuse would blow out due to the large current.

[Means for solving problems]

The present invention provides an air mix door control means 3 that controls the opening degree of the air mix door based on a comprehensive signal T.
4, a fixed position setting means 61 for setting the opening degree of the air mix door to an intermediate fixed position, and a switching means 6 for selecting one of these control signals.
2, the blower is set to stop until the temperature Tw detected by the water temperature sensor reaches the first set level, and when the temperature Tw exceeds the first set level, the blower is stopped in conjunction with the opening of the air mix door. Blower speed setting means F for setting the speed of
Then, before the temperature Tw reaches the predetermined first setting level, the switching means 62 switches to the home position setting means 6.
When the first set level is reached, the blower starts to be energized and the switching means 62 switches the air mix door control means 34 to the first setting level.
and heating start control means H for selecting the control signal.

By doing so, the heating control at the time of starting the engine is made appropriate.

[Effect]

Before the cooling water temperature Tw reaches a predetermined first set level, the air mix door is set to an intermediate position by the output of the fixed position setting means 61. water temperature
When Tw rises and reaches the first setting level, it begins to rotate at a low speed corresponding to the intermediate position of the air mix door. At the same time, the air mix door begins to be controlled by the output of the air mix door control means. As a result, the speed of the blower changes from low speed to high speed according to the opening degree of the air mix door by the blower speed setting means.

〔Example〕

FIG. 1a is a main circuit diagram showing an embodiment of a vehicle air conditioner according to the present invention, and the same parts as in FIG. 2 are denoted by the same reference numerals. In the figure, reference numeral 61 denotes a fixed position setting means consisting of two resistors r ₁ and r ₂ and their midpoint terminal C, which outputs an intermediate signal for setting the air mix door to a substantially intermediate position. As described above, this fixed position setting means 61 generates a control signal for setting the air mix door at the corresponding target position based on the comprehensive signal T, which is a variable signal obtained by calculating at least the vehicle interior temperature Tr and the set temperature Td. This corresponds to the air mix door control means 34 that outputs the . 62 is each means 61, 3 for outputting control signals for these air mix doors.
A relay that selects one of the four outputs.
This is a switching means controlled by RY ₁ . An air mix door drive actuator 50 is connected to the output terminal side of the switching means 62, and a blower speed setting means F for setting the speed of the blower 3 in conjunction with the air mix door is included in the actuator 50.
is provided.

The blower speed setting means F is connected via the blower drive circuit 30 to the "auto" side contact of the blower operating mode setting switch _SW1 . The "manual" side contact of switch SW ₁ has a blower means selection switch mechanism.
SW ₂ is connected. The common contact side of the blower operation mode setting switch _SW1 is connected to the blower ₃ via a relay RY2.

H is a heating start control means, which includes two comparators.
H ₁ , H ₂ , a resistor _{r 1} for supplying a variable potential to each comparator H ₁ , _{H 2} , and a thermistor Th serving as a water temperature sensor 45; A series circuit of resistors r ₄ to _{r 6} for supplying constant potentials corresponding to a set level (for example, 30°C) and a second set level (for example, 28°C), and other resistors r ₂ ,
It is composed of r ₃ , r ₇ to r ₉ . and comparator H ₁
The output of the comparator H2 is connected to the base of the switching transistor Tr ₁ whose emitter is grounded via a resistor r ₁₀ , and the output of the comparator H ₂ is connected to the base of the switching transistor Tr 1 whose emitter is also grounded via resistors r ₉ and r ₁₁ .
connected to the base of Tr ₂ , and the switching means 6
The second relay _RY1 is connected to the collector of the transistor _Tr2 , and the relay _RY2 is connected to the collector of the transistor _Tr1 . Further, the collector of the transistor Tr ₁ is connected to the base side of the transistor Tr ₂ .

Next, the operation of this embodiment will be explained using the graph shown in FIG. 1b. Now, after starting the engine, the output of the coolant temperature sensor 45 is at the second setting level (28°C).
When it reaches, the output of comparator _H2 becomes H level. As a result, transistor Tr ₂ is turned on, energizing the coil of relay RY ₁ and switching means 62.
The switching contact falls to the output side of the fixed position setting means 61. That is, since the switching means 62 selects the output of the fixed position setting means 61, the air mix door drive actuator 50 rotates the air mix door from the previous full hot (FHOT) position to the approximately 50% intermediate position. let At this time, the speed setting means F operates in conjunction with the actuator 50 to set the blower to the low speed side. However, the blower has not been started. That is, the blower is set to a stopped state by the blower speed setting means F until the temperature Tw reaches the first set level.

When the temperature of the cooling water eventually rises and reaches the first set level (30° C.), the output of the comparator _H1 becomes H level. This turns on transistor Tr ₁ and turns on relay RY ₂ . That is, the drive circuit for the blower 3 is now energized for the first time, and the blower 3 begins to rotate at a low speed (LOW) corresponding to the intermediate position of the air mix door. On the other hand, since the collector of transistor Tr ₁ is connected to the base side of transistor Tr ₂ , transistor Tr ₁
The transistor Tr 2 is turned off by turning on the transistor Tr ₂ .
That is, this causes the relay RY ₁ to return to its original state, and the switching means 62 selects the output of the air mix door control means 34 and supplies it to the air mix door driving actuator 50 . At this time, if the outside air temperature is low and the overall signal T has a value that puts the air mix door into the full hot mode, the actuator 50 begins to rotate the air mix door from the approximately intermediate position side to the full hot mode side. Along with this, the speed of the blower 3 is shifted from low speed to high speed by the blower speed setting means F. After that, the speed of the air mix door and the blower are controlled based on the control signal from the air mix door control means 34.

〔effect〕

As explained above, according to the present invention, the opening state of the air mix door is set in advance to a position approximately intermediate between the full hot mode and the full cool mode by the heating activation means, and when the temperature of the cooling water reaches a predetermined temperature, the blower is turned on. Since the speed is set by the output of the air mix door control means when the engine starts, it is possible to properly control the heating at the time of starting the engine, which helps improve the feeling and prevents a sudden large current from flowing to the blower. It can prevent deterioration of internal contacts and eliminate the problem of fuse blowouts.

[Brief explanation of the drawing]

FIG. 1a is a circuit diagram of a main part showing an embodiment of a vehicle air conditioner according to the present invention, FIG. 1b is a graph explaining its operation, FIG. 2 is a simplified configuration diagram showing a conventional example, and FIG. 3A and 3B are a front view and a top view of essential parts showing a conventional air mix door driving actuator 50, and FIG. 3C is a graph explaining the operation of the conventional example. H... Heating starting means, 61... Fixed position setting means, 62... Switching means.

Claims (1)

[Claims] 1. An air mix door control means 34 that sets the air mix door to a target position based on a comprehensive signal T obtained by calculating at least the vehicle interior temperature Tr and the set temperature Td, and sets the air mix door to an approximately intermediate position. a fixed position setting means 61 that outputs an intermediate signal for the air mix door, and a switching means 6 that selects either the output of the air mix door control means 34 or the output of the fixed position setting means 61 and supplies it to the air mix door driving actuator 50.
2, the blower is set to a stopped state until the temperature Tw detected by the water temperature sensor reaches a first set level, and when the temperature Tw exceeds the first set level, the air mix door is operated in conjunction with the air mix door driving actuator 50. a blower speed setting means F for setting the blower from a low speed to a high speed direction as the blower rotates from an approximately intermediate position side to a full hot mode side or a full cool mode side; and before the temperature Tw reaches a first setting level. The switching means 62 is switched in advance so that the output of the fixed position setting means 61 is set to the air mix door driving actuator 5.
When the temperature Tw reaches the first set level, the switching means is switched so that the output of the air mix door control means 34 is supplied to the air mix door drive actuator 50. 1. An air conditioner for a vehicle, comprising heating start control means H for shifting an air mix door to control based on a comprehensive signal T. 2 The heating start control means H is configured such that the temperature Tw is the first
When the second set level lower than the set level is reached, the switching means 62 is switched and the position setting means 6 is set.
2. The air conditioner for a vehicle according to claim 1, wherein one output is supplied to an air mix door drive actuator 50.