JPH05162533A - Air conditioner for vehicle - Google Patents

Abstract

PURPOSE:To provide an air conditioner for vehicle, which can control a large power electric heater and an air conditioner so as to be coupled well. CONSTITUTION:When all of a blower switch 23, a PTC heater switch 24 and a max hot switch 20 are turned on and the engine cooling water is at a predetermined temperature or less, a control circuit 22 controls a relay coil 21a so as to be electrified. When the relay coil 21a is electrified, a relay contact point 21a is turned on to apply the voltage to a PTC heater 16.

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,
Especially effective during warm-up.

[0002]

2. Description of the Related Art As disclosed in Japanese Patent Laid-Open No. 60-33121, when the engine cooling water temperature is low, the blower is stopped or its applied voltage is reduced to reduce the amount of blown air from the blower, and 2. Description of the Related Art Conventionally, there is known a vehicle air conditioner that gradually increases the amount of air blown as the engine cooling water temperature rises when the engine cooling water temperature rises above a predetermined temperature.

[0003]

For example, in a region where the cold is severe, the temperature inside the passenger compartment is considerably low in the morning, and there is a strong demand to immediately blow warm air into the passenger compartment to warm the passenger compartment. However, when the hot air is blown into the vehicle interior after the engine cooling water temperature is equal to or higher than the predetermined temperature as in the above-mentioned conventional technique, the vehicle interior remains at a low temperature until the engine cooling water temperature reaches the predetermined temperature. Yes, during this time the crew must feel cold.

Therefore, in order to solve the above problem, it has been conventionally considered to heat the passenger compartment by using an electric heater even if the engine cooling water does not reach a predetermined temperature. However, since the alternator is commonly used, only an electric heater of about 150 watts can be mounted in the past. For this reason, the temperature rise by the electric heater was only about 5 ° C. when the blower air flow rate was Lo, so the electric heater was controlled separately from the air conditioner.

However, recently, a system for electrically heating the window glass to remove the fogging of the window glass has been put into practical use, and a dedicated alternator or a large capacity alternator and a booster for this system have been put into practical use. And
Along with this, the use of high-power electric heaters has become a reality.

[0006] However, in the above-mentioned high power electric heater, there is a problem in that excess and deficiency of heating may occur unless the interlocking control with the existing air conditioner is taken into consideration. Therefore, it is an object of the present invention to provide a vehicle air conditioner that can control a high-power electric heater and an air conditioner so as to have a good interlocking relationship.

[0007]

In order to achieve the above object, the present invention allows air to pass through a heater core heated at engine cooling water temperature by a blower, and hot air passing through the heater core is blown into a vehicle cabin from an outlet. An air conditioner for a vehicle that blows out, wherein an electric heater provided in the passage of the hot air to generate heat by the electric power in the vehicle, a heat generation state detection unit that generates a signal according to a heat generation state of the electric heater, A water temperature sensor that detects an engine cooling water temperature and generates a water temperature signal, and is connected to the heat generation state detection means, the water temperature sensor, and the blower, and the blower is responsive to the water temperature signal and the signal according to the heat generation state. The gist of the present invention is an air conditioning system for a vehicle, which is provided with a blower control means for controlling the amount of blown air.

[0008]

The control means in the present invention not only controls the engine cooling water temperature based only on the water temperature signal as in the prior art, but also controls the air flow rate of the blower based on both the water temperature signal and the heat generation state of the electric heater. Therefore, it is possible to control the warm air blown from the air outlet into the vehicle compartment so that the temperature of the passenger can be satisfied.

[0009]

As described above, according to the present invention, the warm air blown into the passenger compartment is controlled so as to reach a temperature that can satisfy the occupant, so that the occupant can enjoy a comfortable feeling.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a schematic configuration diagram showing an embodiment of the vehicle air conditioner of the present invention in which a PTC heater is provided in the unit.

In one embodiment of the present invention, as shown in FIG.
An inside air intake port 2 and an outside air intake port 3 are formed in the most upstream part of the case 1, and these are opened and closed by an inside / outside air switching damper 4. A fan 6 driven by a blower motor 5 is provided downstream of the inside / outside air switching damper 4.
In one embodiment, the blower is composed of the blower motor 5 and the fan 6.

Downstream of the fan 6, an evaporator 7 that cools the air blown from the fan 6, a heater core 8 that heats the air, and an amount of air that flows through the heater core 8 are adjusted so that the air blown into the vehicle interior is controlled. Air mix dampers 9 for adjusting the temperature are respectively provided.

At the most downstream side of the case 1, a defroster outlet 10 for blowing air toward the windshield, a face outlet 11 for blowing air toward the upper half of the occupant,
And foot outlets 12 for blowing air toward the feet of the occupant. The amount of air blown out from each of these air outlets is determined by the defroster damper 1
3, the face damper 14, and the foot damper 15, respectively.

A PTC heater 16 which constitutes an electric heater is disposed downstream of the foot damper 15. The PTC heater 16 uses an alternator (not shown) as a power source, and its rated power is 800 watts. And 8 to the PTC heater 16
By energizing at 00 watts, the fan 6 is Lo
The air can be raised by about 25 ° C. when driven by.

Next, the control system of the above embodiment is shown in FIG.
Will be explained. Reference numeral 21 is a relay, and the relay contact 21b short-circuits the fuse 25 and the PTC heater 16 when the relay coil 21a is energized. Then, the voltage (12V) from the battery 27 is boosted to about 150V by the booster circuit 26, and the voltage is applied to the PTC heater 16. When the relay coil 21a is de-energized, the relay contact 21b is connected to the fuse 25 and the PTC heater 16.
And open.

In addition to the engine cooling water temperature signal from the water temperature sensor 19, an internal air temperature signal from an inside air sensor, an outside air temperature signal from an outside air sensor, a solar radiation signal from an insolation sensor, etc. are supplied to a control circuit 22 as a blower control means. input. Further, the control circuit 22 inputs a signal for determining whether all of the max hot switch 20, the PTC heater switch 24, and the blower switch 23 are on, and a signal for simply determining whether the blower switch 23 is on. ..
Here, the max hot switch 20 is a switch that is turned on by the damper 9 coming into contact with the case 1 when the air mix damper 9 (FIG. 1) is in the max hot position, and the PTC heater switch 24 is manually turned on and off by an occupant. It is a switch that can be set. In one embodiment, the heat generation state detecting means is composed of the PTC heater switch 24.

Based on these signals, the control circuit 22 to which each of the above signals has been input receives a target temperature (hereinafter referred to as T
AO) is calculated, and the opening degree of the inside / outside air switching damper 4, the applied voltage to the blower motor 5, the opening degree of the air mix damper 9, the dampers 13, 14, 15 are calculated based on the calculated result.
And the control signal is output to each actuator.

Reference numeral 17 denotes an idle-up actuator for adjusting the idle opening of a throttle valve (not shown) by changing the negative pressure supplied to itself, and the negative pressure is idle-up VSV (vacuum switching valve). It is adjusted by opening and closing 18. The opening / closing of the idle-up VSV 18 is adjusted by a control signal from the control circuit 22 to which the above signals are input.

The relay coil 21a has a signal for determining whether all of the max hot switch 20, the PTC heater switch 24 and the blower switch 23 are on, and a water temperature notifying that the engine cooling water temperature is below a predetermined temperature. Power is supplied when signals from the sensor are input, and not supplied when these signals are not input.

That is, not only the blower switch 23 is turned on, but it is determined that the warm-up should be performed based on the calculation result of the target outlet temperature (TAO), the air mix damper 9 is set to the max hot position, and PT
Only when the C heater switch 24 is turned on and the engine cooling water temperature is equal to or lower than a predetermined temperature, the relay coil 21a
Since the PTC heater switch 24 is turned on, the blower switch 23 is not turned on, the warm-up control is not being performed, or the engine cooling water has warmed to a certain degree and its temperature reaches a predetermined temperature. In the above case, the relay coil 21a is not energized and the PTC heater switch 24 is not turned on.

Next, the operation of the above embodiment will be described. For example, when the ignition switch is turned on early in the morning in winter and the auto air conditioner switch is turned on, the engine cooling water temperature is still cold. Further, since the outside air temperature and the inside air temperature are low, it is determined from the calculation result of the target outlet temperature (TAO) that the warm-up control should be performed, the air mix damper 9 moves to the max hot position, and the max hot switch 20 is turned on. To do. Also, it is assumed that the occupant has not manually turned off the blower switch.

In such a case, when the passenger turns on the PTC heater switch 24, that is, the relay coil 21a.
When the condition that the power is turned on is satisfied, the blower control is performed with the characteristics shown by the solid line in FIG. That is, since the PTC heater 16 can quickly warm the air, a voltage is applied to the blower motor 5 until the engine cooling water temperature reaches a predetermined temperature (between f and c in the figure) after the auto air conditioner switch is turned on. Then, it blows out into the vehicle interior with Lo air volume.

When the engine cooling water temperature exceeds the predetermined temperature, the control circuit 22 of FIG. 1 determines from the signal from the water temperature sensor 19 that the engine cooling water temperature has exceeded the predetermined temperature, so that the relay coil 21a is not energized and the PTC
Even though the heater switch 24 is on, P
The TC heater 16 is turned off. And the blower air volume characteristic is
As shown by the solid line in FIG. 1, the characteristics are as usual.

As described above, the PTC heater 16 is controlled so as to be turned off when the engine cooling water temperature becomes higher than the predetermined temperature. The engine cooling water temperature is controlled when the engine cooling water temperature becomes higher than the predetermined temperature. Since the heater core 8 as a heat source can sufficiently heat the interior of the vehicle,
This is to avoid consuming unnecessary power by turning off the PTC heater 16 that consumes a large amount of power.

As described above, the engine cooling water temperature is cold when the automatic air conditioner switch is turned on, and it is determined that the warm-up control should be performed based on the calculation result of the target outlet temperature (TAO). When the switch 20 is turned on and the blower switch is not turned off manually by the passenger, if the PTC heater switch 24 is turned off without being turned on,
Of course, the PTC heater 16 is not turned on, and the blower is controlled according to the characteristic shown by the broken line in FIG. That is, as in the conventional case, when the engine cooling water temperature is low, no voltage is applied to the blower motor 5 and the amount of air blown into the vehicle interior is set to zero. When the engine cooling water temperature rises to some extent, the applied voltage is gradually increased to increase the amount of air blown into the vehicle interior.

As described in detail above, in the above-mentioned one embodiment, P
Since the TC heater 16 can quickly warm the air, it is possible to blow hot air into the passenger compartment even when the engine cooling water temperature is low. In one embodiment, when the engine cooling water temperature reaches a predetermined temperature, the PTC heater switch 2
Since the PTC heater 16 is controlled so as to be turned off even when 4 is turned on, wasteful power consumption can be prevented.

In one embodiment, the PTC heater switch 24 is a manual switch, so that
A person who wants to use the heater 16 to warm the interior of the vehicle as soon as possible turns on the PTC heater switch 24 to blow out warm air, and a person who does not use the PTC heater switch 24.
By turning off, the conventional control is performed, and both of them can perform satisfactory control.

Further, in one embodiment, a diesel vehicle (especially a wagon vehicle with a wide cabin) has a high engine thermal efficiency, a small amount of heat radiated to the engine cooling water, and a hot water heater using the cooling water as a heat source is not effective. ), PT
The C heater 16 is not only used during warm-up control,
It is extremely effective even during steady-state control, and a comfortable feeling of heating can be obtained during riding in winter.

In the above-described embodiment, the relative relationship between the engine cooling water temperature and the voltage applied to the blower motor 5 has the characteristic shown in FIG. 3, but it may have the characteristic shown in FIG. In this case, when the outside air temperature is −20 ° C. and the air volume is Hi, and the engine cooling water temperature at the point b in the figure is 35 ° C., the temperature of the air blown into the passenger compartment is about 30 ° C. when the PTC heater 16 is off.
Becomes The engine cooling water temperature at point g in the figure is 10
Assuming that the temperature is ℃, the air temperature inside the vehicle is
When the PTC heater 16 is on, the temperature is about 5 ° C. when it is off, but it is about 30 ° C., which is the same as the temperature at the point b in the figure.

That is, if the PTC heater 16 is turned on when the engine cooling water temperature reaches the point g in the figure, it is possible to obtain warm air of a comfortable temperature from the beginning at an earlier timing than before.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a control system of an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram showing an air conditioner using the one embodiment.

FIG. 3 is a characteristic diagram showing a relative relationship between an engine cooling water temperature and a blower voltage in the one embodiment.

FIG. 4 is a characteristic diagram showing a relative relationship between an engine cooling water temperature and a blower voltage in another embodiment.

[Explanation of symbols]

 5 Blower motor as blower 6 Fan as blower 8 Heater core 12 Foot outlet 16 PTC heater as electric heater 19 Water temperature sensor 22 Control circuit as blower control means 24 PTC heater switch as heat generation state detecting means

Claims (2)

[Claims] 1. An air conditioner for a vehicle, wherein air is passed through a heater core heated by engine cooling water temperature by a blower, and hot air is blown through the heater core into a vehicle interior from an outlet through a hot air passage. An electric heater that is provided inside and that generates heat with electric power in the vehicle, a heat generation state detection unit that generates a signal according to a heat generation state of the electric heater, a water temperature sensor that detects the engine cooling water temperature and generates a water temperature signal, And a blower control unit that is connected to the heat generation state detection unit, the water temperature sensor, and the blower, and that controls a blow rate of the blower according to the water temperature signal and a signal according to the heat generation state. Air conditioning system for vehicles. 2. The air outlet comprises a foot air outlet that blows out the warm air to the feet of an occupant of the vehicle, the electric heater is attached to the foot air outlet, and the heat generation state detection means is provided in the electric heater. The blower control means comprises a switch means for controlling a heat generation state, the blower control means changes a blower flow rate control pattern of the blower with respect to the water temperature signal depending on whether or not the switch means energizes the electric heater, and the engine cooling water temperature is The vehicle air-conditioning system according to claim 1, wherein the air-conditioning system is a unit that increases the amount of air blown by the blower as the air-conditioner increases.