JP2000153709A - Vehicular air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make the time of idling stop of an engine longer, thereby increasing the rate of fuel consumption. SOLUTION: A compressor control pattern is set so as to be different when a car runs and when the car stops. In the compressor control pattern, in a range where a target blowing wind temperature To exceeds a preset value To2, an air temperature (shown by a solid line of (2)) Tint after passing through an evaporator at which a compressor is stopped when the car stops is higher than an air temperature Tint (shown by a broken line of (1)) after passing through the evaporator at which the compressor is operated when the car runs. As a result, as long as there is no request for operating an engine other than an air conditioner, the engine is stopped immediately when the car stops. Therefore, it is possible to enhance fuel economy by the length of stop time.

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 for driving a compressor by the power of an engine.

[0002]

2. Description of the Related Art A vehicle air conditioner having a compression refrigeration cycle for driving a compressor by the power of an engine is known. In this type of vehicle air conditioner, the operation and stop of the compressor are controlled based on the air temperature after passing through the evaporator.

[0003] Further, there is known a vehicle in which the idling operation of the engine is stopped when the vehicle stops to improve the fuel consumption rate (hereinafter referred to as fuel efficiency).

[0004]

However, in a vehicle equipped with an air conditioner that drives the compressor by the power of the engine, the idling operation of the engine is immediately stopped when the condition for operating the compressor is satisfied when the vehicle is stopped. There is a problem that the fuel efficiency is worsened.

An object of the present invention is to improve the fuel consumption rate by increasing the idling stop time of the engine.

[0006]

The present invention will be described with reference to FIG. 2 showing a compressor control pattern according to an embodiment. The invention according to claim 1 is mechanically connected to an engine via a clutch. A compressor driven by the power of the engine and a heater core located downstream of the evaporator can change the ratio of air passing through the heater core and air bypassing the heater core to adjust the temperature of the air blown into the cabin. A vehicle interior air-conditioning unit, a calculating means for calculating a target blown air temperature To based on at least a vehicle interior temperature set value, a vehicle interior temperature, an outside air temperature and a solar radiation amount, and a detecting means for detecting an air temperature Tint after passing through an evaporator. Determining whether to start or stop the compressor based on the target blown air temperature To and the air temperature Tint after passing through the evaporator. Compressor control means having a compressor control pattern, opening and closing the compressor clutch according to the compressor control pattern, and engine stop request means for requesting the engine control device to stop the engine when the compressor is stopped when the vehicle is stopped. The compressor control means includes: an air temperature Tint (shown by a solid line) after passing through an evaporator that stops the compressor when the vehicle stops, and an air temperature Tint after passing through an evaporator that drives the compressor during traveling. (Indicated by the dashed line) of the compressor. According to a second aspect of the present invention, a compressor mechanically connected to the engine via a clutch and driven by the power of the engine, and a heater core disposed downstream of the evaporator, bypassing the air passing through the heater core and the heater core. An air conditioning unit that can adjust the temperature of the air blown into the vehicle interior by changing the ratio of the air to be blown into the vehicle interior, and the target air temperature To to be blown out based on at least the vehicle interior temperature set value, the vehicle interior temperature, the outside air temperature and the amount of solar radiation Calculating means for calculating, detecting means for detecting the air temperature Tint after passing through the evaporator, and a compressor control pattern for determining whether to start or stop the compressor based on the target blown air temperature To and the air temperature Tint after passing through the evaporator. Open and close the compressor clutch according to this compressor control pattern An air conditioner for a vehicle, comprising: a compressor control means; and an engine stop requesting means for requesting the engine control device to stop the engine when the compressor is stopped when the vehicle is stopped. The compressor control pattern is set, and the air temperature Tint (shown by a solid line) after passing through the evaporator that stops the compressor when the vehicle stops is determined only when the target blown air temperature To exceeds the predetermined value To2. Air temperature after passing Tin
It has a higher compressor control pattern than t (indicated by the dashed line). The vehicle air conditioner of claim 3 is
The compressor control pattern when stopping (Fig. 2)
In the range where the target outlet air temperature To exceeds the predetermined value To1, the air temperature Tint after passing through the evaporator, which determines the operation and stop of the compressor, becomes equal to the target outlet air temperature To.
The compressor control pattern during running (FIG. 2) is set to be constant in proportion to the air temperature Tint after passing through the evaporator, which determines the operation and stop of the compressor, irrespective of the target blowing air temperature To. It has a control pattern.

In the section of the means for solving the above-described problem, a diagram of one embodiment is used for easy understanding of the description, but the present invention is not limited to this embodiment. .

[0008]

According to the first aspect of the present invention, the compressor control means controls the compressor such that the air temperature after passing through the evaporator for stopping the compressor when the vehicle is stopped is higher than the air temperature after passing the evaporator for driving the compressor during traveling. Since the engine has a pattern, the engine is immediately stopped when the vehicle stops, unless there is a request for operation of the engine other than the air conditioner, and the fuel efficiency can be improved accordingly. According to the invention of claim 2, different compressor control patterns are set for running and stopping, and only when the target blowing air temperature exceeds a predetermined value, the air temperature after passing through the evaporator for stopping the compressor when stopping is reduced. Since the compressor control pattern is higher than the air temperature after passing through the evaporator that drives the compressor during traveling, the target blow-off air temperature does not exceed a predetermined value, and when the occupant wants a relatively low blow-off air temperature, Since the compressor is not always stopped, the comfort of the occupants is improved.
According to the third aspect of the present invention, when the vehicle is stopped, the compressor control pattern is such that the air temperature after passing through the evaporator that determines the operation and stop of the compressor is proportional to the target air temperature when the target air temperature exceeds a predetermined value. Since the compressor control pattern during running and the air temperature after passing through the evaporator that determines the operation and stop of the compressor have a constant control pattern irrespective of the target blowing air temperature, the compressor The continuous operation time becomes longer,
Fuel consumption can be improved by reducing load fluctuations on the engine. On the other hand, when the vehicle is stopped, the time during which the compressor is intermittently operated becomes longer, and the operation time of the engine is shortened, so that fuel efficiency can be improved.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a hybrid vehicle running by driving force of an engine and / or a motor will be described. The present invention is not limited to a hybrid vehicle, and can be applied to a conventional engine vehicle equipped with an air conditioner that drives a compressor by the power of an engine.

FIG. 1 shows a configuration of an embodiment. The compressor 1 is connected to the engine 3 via the magnetic clutch 2.
The compressor 1 is operated and stopped by controlling on / off of the magnetic clutch 2. The refrigerant compressed by the compressor 1 is cooled by the condenser 4, and exchanges heat with the air in the cabin by the evaporator 5 to cool the cabin. The compressor 1, the condenser 4, and the evaporator 5 constitute a compression refrigeration cycle of the air conditioner. Although the compression refrigeration cycle includes other devices such as a liquid tank, they are not directly related to the present invention, so that illustration and description thereof are omitted.

On the other hand, the cooling water of the engine 3 circulates through a radiator 6 and a valve 7, and is cooled by the running wind pressure of the vehicle or a blower fan 8 by the radiator 6, and also passes through an electric water pump 9 and a heater core 10. Circulates and heats the cabin.

The air conditioner controller 11 is composed of a microcomputer and its peripheral parts, and controls the driving of the air conditioner. The vehicle controller 12 includes a microcomputer and its peripheral components, and performs overall control of the hybrid vehicle. Further, the engine controller 13 includes a microcomputer and its peripheral components, and performs fuel injection control, torque control, rotation speed control, ignition control, and the like of the engine 3. The controllers 11 to 13 communicate with each other by a communication device.

The air conditioner controller 11 includes a sensor 14 for detecting an air temperature Tint after passing through the evaporator 5, other sensors (not shown) such as an internal temperature sensor, an external temperature sensor, a solar radiation sensor, and a fan motor. And actuators (not shown) such as an opening / closing actuator and an air mixing door driving actuator. Also connected to the air conditioner controller 11 are an automatic air conditioner switch 15 for operating the air conditioner in the automatic air conditioning mode, a full air conditioner switch 16 for giving priority to the air conditioner operation, and an air conditioner off switch 17 for stopping the air conditioner operation.

The vehicle controller 12 includes an electric water pump 9 for circulating engine cooling water to the heater core 10 when the engine is stopped, and a sensor 1 for detecting a vehicle speed V.
8. A sensor 19 for detecting the pressure Pd of the refrigerant circulating in the compression refrigeration cycle, a sensor 20 for detecting the cooling water temperature Tw of the engine 3, and a charge state of a high-voltage battery (not shown) for driving the traveling motor. Sensor 2
1. The above-described compressor magnetic clutch 2 and the like are connected.

The engine controller 13 performs a so-called idling stop control for stopping the idling operation of the engine 3 when the vehicle stops. However, if it is necessary to drive the compressor 1 to cool the vehicle interior, or if the engine cooling water temperature Tw is too low when heating the vehicle interior and the engine 3 needs to be warmed up, a high pressure is applied to the traveling motor. For example, when the state of charge (SOC) of a high-voltage battery (not shown) for supplying power is reduced, the engine 3 is operated even when the vehicle is stopped.

An air conditioning unit for generating air conditioning air is installed in the vehicle interior. Inside this air conditioning unit, a door for taking in inside air or outside air in order from the upstream, a blower fan that sends air conditioning air into the unit, an evaporator that cools the air conditioning air, a heater core that warms the air conditioning air, and a heater core An air mix door that adjusts a ratio of air passing through and air bypassing the heater core, and an air mix chamber that mixes air passing through the heater core and air bypassing the heater core are provided. Such an air conditioning unit in a vehicle compartment is known, and illustration and detailed description thereof are omitted.

FIG. 2 shows a compressor control pattern according to the embodiment, and FIG. 3 shows a control result of the compressor immediately after stopping. In this embodiment, as shown in FIG. 2, different compressor control patterns are set for running and stopping, based on the target blown air temperature To and the air temperature Tint after passing through the evaporator. In FIG. 2, the air temperatures Tint1 to Tint3 after passing through the evaporator.
Is

## EQU1 ## It is assumed that Tint1 <Tint2 <Tint3.

Here, the target outlet air temperature To is the temperature of conditioned air blown from outlets such as a foot outlet, a vent outlet, and a defroster outlet in the vehicle cabin, and is a temperature of an air mix door (not shown). Opening X
It changes according to m. The target outlet wind temperature To is set by the air conditioner controller 11 to a vehicle interior temperature set value Tptc,
It is calculated based on the vehicle interior temperature Tinc, the outside temperature Tamb, the amount of solar radiation Qsun, and the like. Many methods for calculating the target blown air temperature To have been introduced, and are not directly related to the present invention.

The running state and the stopped state of the vehicle are determined by determining whether the vehicle speed V detected by the sensor 18 is a predetermined value V1.
(V1 is a value close to 0).
Is set to a running state when exceeds a predetermined value V1.

When the vehicle is running, the compressor 1 is operated (on-dashed line) and stopped (OFF-solid line) according to the control pattern shown in FIG. That is, regardless of the target blown air temperature To, when the air temperature Tint passing through the evaporator 5 exceeds the predetermined value Tint2, the magnet clutch 2 is turned on to operate the compressor 1,
Cool the cabin. When the air passing through the evaporator 5 falls below the predetermined value Tint1, the magnet clutch 2 is turned off and the compressor 1 is stopped.

On the other hand, when the vehicle is stopped, the compressor 1 is operated (on-broken line) and stopped (OFF-solid line) according to the control pattern shown in FIG. The idling stop control of the engine 3 is performed.

When the target blown air temperature To is equal to or lower than the predetermined value To1, if the air temperature Tint passing through the evaporator 5 exceeds the predetermined value Tint3 regardless of the target blown air temperature To1, the magnet clutch 2 is turned on and the compressor 1 is turned on. drive. At this time, if the engine 3 is stopped, the engine 3 is started. When the air temperature Tint after passing through the evaporator becomes equal to or lower than the predetermined value Tint1, the magnet clutch 2 is turned off and the compressor 1 is stopped. At this time, if there is no request for operating the engine other than the air conditioner, the engine 3 is stopped.

When the target outlet air temperature To exceeds the predetermined value To1, the air temperatures Tint1 and Tint3 after passing through the evaporator for determining the operation and stop of the compressor 1 increase in proportion to the target outlet air temperature To. Then, when the air temperature Tint after passing through the evaporator exceeds a temperature Tint3 corresponding to the target blowing air temperature To, the magnet clutch 2 is turned on and the compressor 1 is operated. At this time, if the engine 3 is stopped, the engine 3 is started. When the air temperature Tint after passing through the evaporator becomes equal to or lower than the temperature Tint1 corresponding to the target blowing air temperature To, the magnet clutch 2 is turned off and the compressor 1 is turned off.
To stop. At this time, if there is no request for operating the engine other than the air conditioner, the engine 3 is stopped.

According to this embodiment, when the vehicle is stopped, an engine operation request other than an air conditioner, such as an engine operation request due to a decrease in the temperature of the engine cooling water during heating or a decrease in the state of charge of the high-voltage battery, as described above. If not, the engine 3 is started when the operation of the compressor 1 is started, and the engine 3 is also stopped when the compressor 1 is stopped. If there is an engine operation request other than the air conditioner, the engine 3 is operated and stopped according to the request.

Therefore, when there is no request for operating the engine other than the air conditioner, the following compressor control result is obtained. In this embodiment, as shown in FIG. 2, when the target blown air temperature To exceeds the predetermined value To2, the compressor stop temperature at the time of stopping (solid line).
Set a compressor control pattern that is higher than (the broken line of) the compressor operating temperature during traveling. Thus, as shown in FIG. 3, when the vehicle stops at time t1, the compressor 1 is stopped whenever the target blown air temperature To exceeds the predetermined value To2, and the engine 3 is also stopped accordingly. That is, unless there is a request to operate the engine other than the air conditioner, the engine is immediately stopped when the vehicle stops, and the fuel efficiency can be improved accordingly.

In a normal vehicle operation pattern, the vehicle often stops for a short time due to a signal or the like. When the target blowing air temperature To exceeds the predetermined value To2, the engine is temporarily stopped immediately after the stop every time such a short stop is performed, and the effect of improving fuel efficiency is great.

Further, in this embodiment, different compressor control patterns are set for running and stopping.
That is, the control pattern during running is a control pattern in which the air temperature Tint after passing through the evaporator, which determines the operation and stop of the compressor, is constant irrespective of the target blowing temperature To, and the control pattern when stopping is the air after passing through the evaporator. The control pattern was such that the temperature increased in proportion to the target blowing temperature To. By setting such a compressor control pattern, during running, the time during which the compressor is continuously operated becomes longer, and the load fluctuation on the engine can be reduced to improve fuel efficiency. Further, when the vehicle is stopped, the time during which the compressor is intermittently operated is lengthened, and the operation time of the engine is shortened, so that fuel efficiency can be improved.

It should be noted that the target blowing air temperature To is a predetermined value To.
If the compressor stop temperature at the time of stopping (solid line) becomes higher than the compressor operating temperature at the time of traveling (dashed line) in a range exceeding 2 in FIG. As shown by a broken line in FIG. 1, the compressor 1 is operated immediately after the vehicle stops, and the fuel efficiency is reduced accordingly.

FIG. 4 is a flowchart showing a compressor control program according to one embodiment. The air conditioner controller 11 includes an auto air conditioner switch 15, a full air conditioner switch 16, and an air conditioner off switch 1.
This control program is executed in accordance with the operation of Step 7.
When the auto air conditioner switch 15 is operated, the compressor control is started from step 1 and
Calculates the target blown air temperature To, and the sensor 14 detects the air temperature Tint after passing through the evaporator.

In step 3, it is checked whether the vehicle speed V is equal to or higher than V1, that is, whether or not the vehicle is running. If the vehicle is running, the process proceeds to step 4, and if the vehicle is stopped, the process proceeds to step 5.
Proceed to. If the vehicle is running, the operation of the compressor 1 is controlled in step 4 in accordance with the control pattern during running shown in FIG. On the other hand, when the vehicle is stopped, in step 5, the operation and stop of the compressor 1 are controlled in accordance with the stop control pattern shown in FIG.

Thereafter, at step 6, the vehicle speed V is increased to a predetermined value V2.
(For example, 30 km / h) or more, and if it is more than the predetermined value V2, the process proceeds to step 7. In hybrid vehicles,
Usually, when the vehicle speed V is high, the vehicle runs by the driving force of the engine. When the vehicle is traveling at high speed by the driving force of the engine, the cooling water temperature Tw is high. In step 7, the cooling water of the engine 3 is guided to the heater core 10 to perform normal heater control. On the other hand, if the vehicle speed V is less than the predetermined value V2, the process proceeds to step 8, and it is determined whether or not the engine cooling water temperature Tw is equal to or higher than the predetermined value Tw1. When the engine cooling water temperature Tw is equal to or higher than the predetermined value Tw1, the process proceeds to step 9. At a low speed, the engine 3 is stopped and the vehicle is running by the driving force of the motor, so the engine water is guided to the heater core 10 by the electric water pump 9. Do the heating. When the vehicle speed V is less than the predetermined value V2 and the engine cooling water temperature Tw is less than the predetermined value Tw1, the process proceeds to step 10, in which the engine 3 is started to secure a heating heat source and the warm-up operation is started.

When the full air conditioner switch 16 is operated, the compressor control is started from step 11, the target blow-off air temperature To is calculated in step 12, and the air temperature Tint after passing through the evaporator is detected by the sensor 14. . Then go to step 4,
The above-described compressor control during traveling is executed. When the air conditioner off switch 17 is operated,
The heater control is started from step 13.

<< Modification of Compressor Control Pattern >>
The control pattern of the compressor 1 may be the pattern shown in FIG. In the pattern shown in FIG. 5, when the target outlet wind temperature To exceeds a predetermined value To3, the air temperatures Tint4 to Tint7 after passing through the evaporator for determining the operation and stoppage of the compressor at the time of traveling and at a stop are determined by the target outlet wind temperature. It is increased at the same rate in proportion to To. Here, the air temperatures Tint4 to Tint7 are:

## EQU2 ## Tint4 <Tint5 <Tint6 <Tint7, and the compressor stop temperature (solid line) when the vehicle stops is the compressor operating temperature during running (dashed line).
Higher than.

According to this control pattern, in addition to the effect of the control pattern shown in FIG. 2, the compressor is operated intermittently during running by the motor of the hybrid vehicle, and accordingly, the time during which idling of the engine is stopped becomes longer. The effect of improving fuel efficiency is obtained.

In the configuration of the above embodiment, the air conditioner controller 11 constitutes the arithmetic means, the compressor control means and the engine stop requesting means, and the vehicle controller 12 and the engine controller 13 constitute the engine control device.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an embodiment.

FIG. 2 is a diagram showing a control pattern of a compressor.

FIG. 3 is a diagram illustrating a control result of a compressor after stopping according to the embodiment;

FIG. 4 is a flowchart showing compressor control according to one embodiment.

FIG. 5 is a diagram showing a modification of the control pattern of the compressor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor 2 Magnet clutch 3 Engine 4 Condenser 5 Evaporator 6 Radiator 7 Valve 8 Blower fan 9 Electric water pump 10 Heater core 11 Air conditioner controller 12 Vehicle controller 13 Engine controller 15 Auto air conditioner switch 16 Full air conditioner switch 17 Air conditioner off switch 18 Vehicle speed sensor 19 Refrigerant pressure sensor 20 Engine cooling water temperature sensor 21 Charge state sensor

Claims (3)

[Claims] A compressor mechanically connected to the engine via a clutch and driven by the power of the engine; a heater core disposed downstream of the evaporator; air passing through the heater core and air bypassing the heater core. And an air-conditioning unit capable of adjusting the temperature of the air blown into the vehicle interior by changing the ratio of the air temperature to the vehicle interior, and calculating the target airflow temperature based on at least the vehicle interior temperature set value, the vehicle interior temperature, the outside air temperature, and the amount of solar radiation. Means, a detecting means for detecting the air temperature after passing through the evaporator, and a compressor control pattern for determining the operation and stop of the compressor based on the target blown air temperature and the air temperature after passing through the evaporator. Compressor control that opens and closes the compressor clutch according to a pattern Means for stopping the compressor when the vehicle stops, wherein the compressor control unit stops the compressor when the vehicle stops. An air conditioner for a vehicle, wherein the air temperature after passing through the evaporator has a compressor control pattern higher than the air temperature after passing through the evaporator that drives the compressor during traveling. A compressor mechanically connected to the engine via a clutch and driven by the power of the engine; a heater core disposed downstream of the evaporator; air passing through the heater core and air bypassing the heater core. And an air-conditioning unit capable of adjusting the temperature of the air blown into the vehicle interior by changing the ratio of the air temperature to the vehicle interior, and calculating the target airflow temperature based on at least the vehicle interior temperature set value, the vehicle interior temperature, the outside air temperature, and the amount of solar radiation. Means, a detecting means for detecting the air temperature after passing through the evaporator, and a compressor control pattern for determining the operation and stop of the compressor based on the target blown air temperature and the air temperature after passing through the evaporator. Compressor control that opens and closes the compressor clutch according to a pattern And an engine stop requesting means for requesting the engine control device to stop the engine when the compressor is stopped when the vehicle is stopped. The air conditioner for a vehicle comprising: Set the compressor control pattern in which the air temperature after passing through the evaporator that stops the compressor when the vehicle is stopped is higher than the air temperature after passing through the evaporator that runs the compressor when the vehicle is running only when the target blown air temperature exceeds the predetermined value. An air conditioner for a vehicle, comprising: 3. The vehicle air conditioner according to claim 1, wherein the compressor control pattern when the vehicle is stopped determines whether to start or stop the compressor when the target blown air temperature exceeds a predetermined value. The control pattern is such that the air temperature after passing through the evaporator increases in proportion to the target blowing air temperature, and the compressor control pattern during running is such that the air temperature after passing through the evaporator that determines the operation and stop of the compressor is the target blowing wind temperature. An air conditioner for a vehicle having a constant control pattern regardless of the vehicle.