JP2000179374A - Vehicle control device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] In a vehicle with an air conditioner having a vehicle engine automatic stop / restart device, the demand for cooling by an air conditioner while suppressing a decrease in the effect of improving fuel efficiency and reducing exhaust gas by stopping the engine is reduced. Providing equipment that can respond. When the engine is automatically stopped and an air conditioner switch is turned on, it is determined whether or not a difference between a target room temperature set by an occupant and an actual room temperature is larger than a predetermined value (step). 70), if a negative determination is made, the compressor of the air conditioner is stopped (step 8)
0). If the determination is affirmative, the engine is restarted (step 100), and the compressor of the air conditioner is driven by the restarted engine (step 110).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic engine stop automatic engine for automatically stopping an engine when a predetermined stop condition is satisfied and automatically restarting the engine automatically when a predetermined restart condition is satisfied. The present invention relates to a control device for a vehicle with an air conditioner having a restart device. In this specification, an air conditioner refers to an air conditioner including a cooling device that compresses a refrigerant by a compressor.

[0002]

2. Description of the Related Art A vehicle equipped with an automatic engine stop automatic restart device for a vehicle that automatically stops an engine under predetermined engine stop conditions and automatically restarts the engine with battery power under predetermined engine restart conditions is known. It is known. For example, there is an apparatus described in JP-A-9-209790. On the other hand, the mounting rate of air conditioners in vehicles has been increasing year by year, and the above-described automatic engine stop automatic restart device is naturally often applied to vehicles with air conditioners.

[0003]

The automatic engine stop automatic restart system aims to improve fuel efficiency and reduce exhaust gas by stopping the engine, and to increase the rate of stopping the engine as much as possible. It is desirable that the conditions for prohibiting or canceling the automatic stop of the engine be reduced as much as possible. on the other hand,
When considering the air conditioner, if the temperature inside the cabin is high,
The occupant wants to keep the air conditioner running even if the engine stops automatically with the above device. Therefore, in a vehicle equipped with an automatic engine stop automatic restart device, for example,
It is known that the engine is not automatically stopped when it is desired to always operate the air conditioner or when the vehicle interior temperature has not reached the set temperature (October 1997).
Monthly publication of the new Prius model, p. 6-53).

[0004] However, when such control is performed, under the above-mentioned conditions, the automatic stop of the engine is canceled regardless of the situation, and the rate of not performing the automatic stop of the engine increases, thereby improving the fuel efficiency by stopping the engine. And the effect of reducing the exhaust gas is reduced. The present invention has been made in view of the above problems, and in a vehicle with an air conditioner having an automatic stop / restart system for a vehicle, there is a demand for cooling of occupants as much as possible while suppressing a decrease in the effects of improving fuel efficiency and reducing exhaust gas by stopping the engine. The goal is to provide a device that can respond to

[0005]

According to the first aspect of the present invention, an automatic engine stop that automatically stops the engine under predetermined engine stop conditions and automatically restarts the engine under predetermined engine restart conditions is provided. A control device for a vehicle with an air conditioner having an automatic restart device, wherein when a cooling request by the air conditioner and an automatic stop of the engine overlap, the driving of the compressor of the air conditioner is stopped, and the compressor is stopped until a predetermined period elapses. Is provided so as not to restart the driving of the motor. With the control device configured as described above, when the cooling request by the air conditioner and the automatic stop of the engine overlap, the driving of the compressor is stopped, and the driving of the compressor is not restarted until a predetermined period has elapsed.

According to the invention described in claim 2, according to claim 1
According to the invention, a control device is provided in which the predetermined period is a period from when the driving of the compressor is stopped to when the occupant feels discomfort associated with stopping the cooling. With the control device configured as described above, when the cooling request by the air conditioner and the automatic stop of the engine overlap, the drive of the compressor is stopped, and the compressor is operated until the occupant feels discomfort due to the cooling stop. Is not restarted.

According to the third aspect of the present invention, the first aspect is provided.
In the invention, a control device is provided which restarts the engine after a predetermined period has elapsed after the driving of the compressor is stopped, and restarts the driving of the compressor by the restarted engine. With the control device configured as described above, when the cooling request by the air conditioner and the automatic stop of the engine overlap, the drive of the compressor is stopped, and the engine is not restarted until a predetermined period has elapsed.

[0008] According to the invention described in claim 4, according to claim 1 of the present invention.
In the invention of the above, the compressor of the air conditioner can be driven by the battery power, and after a predetermined period has elapsed after the driving of the compressor is stopped, the compressor is driven by the battery power as long as the state of charge of the battery is equal to or higher than a predetermined level. The control device according to claim 1, wherein the engine is restarted when the level falls below a predetermined level, and switching to driving by the engine is provided. In the control device configured as described above, when the cooling request by the air conditioner and the automatic stop of the engine overlap, the drive of the compressor is stopped. The engine is not restarted as long as the can be driven.

According to the present invention, there is provided an automatic engine stop automatic restart device for automatically stopping the engine under predetermined engine stop conditions and automatically restarting the engine under predetermined engine restart conditions. A control device for a vehicle equipped with an air conditioner, wherein when the cooling request by the air conditioner and the automatic stop of the engine overlap, the driving of the compressor of the air conditioner is stopped, and the target cabin temperature set by the occupant and the actual cabin temperature are set. Is provided, the control device restarts the driving of the compressor of the air conditioner when the difference of the air conditioner becomes larger than a predetermined value. In the control device configured as described above, when the cooling request by the air conditioner and the automatic stop of the engine overlap, the drive of the compressor of the air conditioner is stopped, and the target cabin temperature set by the occupant and the actual cabin temperature are set. When the difference becomes larger than a predetermined value, the operation of the compressor of the air conditioner is restarted.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 2 shows a drive system common to each embodiment of the present invention. In FIG.
1 is an engine mounted on a vehicle, and 2 is an automatic transmission. The engine 1 has a motor / generator 3 functioning as a motor and a generator for restarting the engine 1 and an electromagnetic clutch 26,
The pulley 22, the belt 8, the pulley 23, and the reduction mechanism R are connected to each other.

The reduction mechanism R is of a planetary gear type and has a sun gear 3
3, including a carrier 34, a ring gear 35, and a brake 3
1. It is incorporated between the motor / generator 3 and the pulley 23 via a one-way clutch 32. Note that the one-way clutch 32 can be replaced with a clutch.

The oil pump 19 for the automatic transmission 2 is directly connected to the crankshaft 1a of the engine 1 as in the prior art.
Reference numeral 11 in the figure denotes a pump for power steering, 16 denotes a compressor for an air conditioner, and the crankshaft 1a of the engine and the motor generator 3 are the pulleys 9, 1.
4 and a belt 8.

Although not shown in FIG. 2, in addition to the above-mentioned auxiliary equipment, an engine oil pump, an engine water pump, and the like are also connected. Reference numeral 4a denotes an inverter electrically connected to the motor generator 3.
The inverter 4a varies the supply of electric energy from the battery 5a, which is a power source, to the motor generator 3 by switching, thereby varying the rotation speed of the motor generator 3. Further, switching is performed such that electric energy is charged from the motor generator 3 to the battery 5a.

The battery 5a is a battery dedicated to driving the motor generator 3, and has a rated voltage of 48V or 36V. On the other hand, the battery 5b has a normal auxiliary equipment rated voltage of 12V, and the battery 5b is connected to the battery 5a via the inverter 4b.

Reference numeral 7 denotes control of intermittent operation of the electromagnetic clutch 26,
And a controller for performing switching control and the like of the inverter 4. As input signals to this controller, an on / off signal from the air conditioner switch 42, an on / off signal of the automatic stop running mode (eco-run) switch 40, an engine speed signal from a NE (engine speed) sensor 49, a shift lever A detection signal from a shift position sensor 45 for detecting a shift position of 44, a signal from an engine coolant temperature sensor 47 also serving as a sensor for estimating and detecting an oil temperature, a vehicle speed sensor 50
, A foot brake signal from the foot brake sensor 51, a hand brake signal from the hand brake sensor 52, a signal from the accelerator opening sensor 54, and the like.

An indicator 46 for notifying the driver of the automatic stop and automatic restart of the engine, that is, when the eco-run is being performed, and an indicator 48 for notifying the driver of the fact that the eco-run is not being performed. Is provided.

When the engine 1 is automatically stopped, the controller 7 outputs a control signal for disconnection to the electromagnetic clutch 26, and the power is not transmitted between the pulley 22 and the engine 1. On the other hand, as will be described later, in the present invention, when the air conditioner is operated even when the engine 1 is stopped, the controller 7 controls the motor / generator 3 to rotate at a torque in consideration of the load of the air conditioner compressor.
Outputs a corresponding switching signal to the inverter 4. At this time, the brake 31 is turned off and the electromagnetic clutch 26 is turned off. In this state, the motor / generator 3 and the pulley 23 are directly connected to each other, and a rotational speed required for driving the accessories 11, 16 and the like can be secured.

In order to use the motor / generator 3 as a generator or to drive the accessories 11 and 16 while the engine is running, the brake 31 is turned off and the electromagnetic clutch 26 is turned off. Are turned on. By doing so, the motor / generator 3 and the pulley 23 are directly connected to each other, preventing the motor / generator 3 and the auxiliary devices 1, 16, etc. from exceeding the allowable rotation speed even when the engine rotation speed increases. can do. It should be noted that even if the one-way clutch 32 is replaced with a one-way clutch, substantially the same operation as described above can be obtained.

Next, when the engine 1 is restarted in the eco-run mode, the controller 7 outputs a signal for turning on the clutch 26 and turns on the brake 31 of the speed reducer R.
A signal is output to make the ring gear 35 unrotatable. When the motor / generator 3 is rotated in this state, the rotation of the sun gear 33 is transmitted to the pinion gear 36, and the ring gear 35 is locked, so that the pinion gear 36 revolves around the sun gear 33 while rotating. Therefore, the carrier 34 in the pinion gear 36 revolves around the sun gear 33, and the pulley 23 coaxial with the carrier 34 also rotates. At this time, the rotation speed of the pulley 23 is such that the rotation speed of the shaft of the motor / generator 3 is reduced at a reduction ratio determined by the number of teeth of the sun gear 33 and the ring gear 35. Therefore, torque sufficient for starting is transmitted from motor generator 3 to engine 1, and the engine is restarted. This leads to the effect that the size of the motor generator 3 can be reduced. In addition, since the pulley 23 rotates, the accessory is also driven at the same time.

The automatic stop and automatic restart of the engine 1 are realized on the controller 7 in accordance with the control program stored in the ROM. The controller 7 determines, for example, that the vehicle speed is zero, the brake pedal is depressed, the accelerator pedal is not depressed, the engine water temperature and the operating oil temperature of the A / T are within a predetermined range, and the SOC (charge state) of the battery is Is within a predetermined range, and the position of the shift lever is D
Or, it is determined that the engine should be automatically stopped on condition that the shift lever is in the N position or simply that the shift lever is in the P position. When it is determined that the engine should be stopped automatically, a command to cut off the fuel supply to the engine 1 is issued. On the other hand, for example, it is determined that the engine should be restarted automatically when the accelerator pedal is depressed or the brake is turned off. Then, when it is determined that the engine should be automatically restarted, a command to restart fuel supply to the engine 1 and restart the engine is issued.

Next, the hill hold control will be described. If the engine 1 is running even when the vehicle is stopped,
As long as the shift lever is at the D position, the forward clutch C1 is engaged, and a creep force for moving the vehicle forward is exerted. Therefore, the vehicle can be prevented from moving backward by this creep force on a slope having a gentle slope. However, in the automatic stop automatic restart device, when the vehicle stops, the engine 1
Creep force does not work. Therefore, when the stopped position is on an uphill road, the vehicle will retreat unless the brakes are strongly depressed.

Therefore, when it is determined that the conditions for automatically stopping the engine are satisfied, hill hold control for suppressing the rotation of the wheels by holding the master cylinder hydraulic pressure of the brake device and holding the braking force is performed. This hill hold control is also realized on the controller 7 by a program. The hill hold control is preferably performed by driving an actuator (not shown) for an antilock brake device (ABS). Further, the rotating shaft connected to the wheels may be mechanically locked. The hill hold control continues the braking force when the transmission is in the traveling position and when the engine 1 is restarted under specific conditions not intended for traveling while the engine 1 is automatically stopped.

Next, control of each embodiment configured as described above will be described. First, a first embodiment will be described.
If the occupant feels discomfort due to the cooling stop after the compressor 16 is stopped, the engine 1 is restarted assuming that a predetermined period has elapsed, and the driving of the compressor 16 by the engine 1 is restarted. When the difference between the target cabin temperature set by the occupant and the actual cabin temperature becomes larger than a predetermined value, it is determined that the occupant feels uncomfortable. The flowchart is shown.

In FIG. 1, in step 20, input signals from various sensors are processed. In step 30, it is determined whether or not the precondition for the automatic engine stop is satisfied. Specifically, each sensor value is normal, the engine water temperature is equal to or higher than a predetermined value, and the AT oil temperature is equal to or higher than a predetermined value. That the SOC of the battery 5a is sufficient,
Each sensor indicates a normal value. If a negative determination is made in step 30, nothing is performed and step 130 is performed.
Jump to and return. If an affirmative determination is made in step 30, the process proceeds to step 40, executes automatic stop control, further proceeds to step 50, executes hill hold control, and proceeds to step 60.

In step 60, it is determined whether or not the air conditioner switch 42 is ON. If a negative determination is made in step 60, that is, if the air conditioner switch 42
If it is set to F, the process jumps to step 90 and sends a signal to the engine automatic stop control execution indicator 46 to indicate that the automatic stop control is being executed, and then to step 1
Proceed to 30 and return. On the other hand, if a positive determination is made in step 60, that is, the air conditioner switch 42 is turned on.
If so, the routine proceeds to step 70, where it is determined whether or not the difference between the target room temperature set by the occupant and the actual room temperature is larger than a predetermined value.

If a negative determination is made in step 70, the process proceeds to step 80, in which a signal for stopping the compressor 16 of the air conditioner is generated, and then the process proceeds to step 90, where the automatic stop control execution indicator 46 for the engine is under automatic stop control. Step 1 after sending a signal to indicate that
Proceed to 30 and return. Conversely, if the determination in step 70 is affirmative, the routine proceeds to step 100, where the engine 1 is restarted. At step 110, the compressor 16 of the air conditioner is driven by the restarted engine 1, and the routine proceeds to step 120, where the automatic engine stop control is performed. A signal is sent to the non-execution indicator 48 indicating that the automatic stop control is not being performed, and the process returns.

Since the first embodiment operates as described above, when the switch of the air conditioner is turned on and the engine 1 is automatically stopped, the difference between the target room temperature set by the occupant and the actual room temperature is determined in advance. When the pressure is equal to or less than the predetermined value, the compressor 16 of the air conditioner is stopped, and after the pressure exceeds the predetermined value, the engine 1 is restarted, and the compressor 16 of the air conditioner is driven by the restarted engine 1. Therefore, after the engine 1 is automatically stopped, the difference between the target indoor temperature and the actual indoor temperature becomes equal to or greater than a predetermined value, and until the engine 1 is restarted, fuel is not consumed and exhaust gas is also discharged. Not done. FIG. 3 is a time chart for explaining the above operation.

When the difference between the target room temperature and the actual room temperature exceeds a predetermined value, the engine 1 is not restarted to drive the compressor 16 of the air conditioner, but the compressor 16 is turned off. The engine 1 may be restarted and the compressor 16 of the air conditioner may be driven when the elapsed time from the preset time reaches a predetermined time obtained by an experiment. In FIG. 3, the time indicated by TD is a time at which the difference between the target room temperature and the actual room temperature becomes equal to or more than a predetermined value.

Next, a second embodiment will be described. In the second embodiment, the target vehicle interior temperature set by the occupant after the compressor 16 is stopped and the actual vehicle interior are set. When the temperature difference becomes larger than a predetermined value, first, the compressor 16 of the air conditioner is driven by the motor generator 3. The power charged in the battery is consumed to drive the air conditioner, and the SOC of the battery is consumed.
Is reduced to a level below a predetermined level, the engine 1 is restarted, and the restarted engine 1 starts the compressor 16 of the air conditioner. FIG. 4 is a flowchart thereof.

This flowchart differs from the flowchart of the first embodiment shown in FIG. 1 in that the process proceeds to step 70 and the case of affirmative determination in step 70 is different.
The other cases are the same, and the description is omitted. If an affirmative determination is made in step 70, it is determined in step 75 whether or not the state of charge SOC of the battery 5a is equal to or higher than a predetermined level. If the determination in step 75 is affirmative, the process proceeds to step 85, in which the compressor 16 of the air conditioner is driven by the motor generator 33, and the process proceeds to step 90 where the automatic stop control execution indicator 46 for the engine is under automatic stop control. A signal indicating the fact is sent and the process returns.

On the other hand, if a negative determination is made in step 75, the engine 1 is restarted in step 100, and the compressor 16 of the air conditioner is driven by the restarted engine 1 in step 110, and the program proceeds to step 120 where the engine 1 A signal indicating that the automatic stop control is not being executed is sent to the automatic stop control non-execution indicator 48, and the process returns. FIG. 5 is a time chart for explaining the above control.

Since the second embodiment is controlled as described above, the difference between the target room temperature set by the occupant and the actual room temperature when the air conditioner switch is ON and the engine 1 is automatically stopped. If it is less than the predetermined value, the compressor 16 of the air conditioner is stopped. When the temperature difference becomes equal to or more than a predetermined value, if the SOC is equal to or more than a predetermined level, the compressor 16 of the air conditioner is driven by the motor generator 3 and the operation is continued until the SOC becomes equal to or less than the predetermined level. When the SOC falls below a predetermined level, the engine 1 is restarted, and the restarted engine 1 causes the compressor 16 of the air conditioner to restart.
Is driven. Therefore, the engine 1 is stopped for a longer time period driven by the motor generator 3 than in the first embodiment, and the fuel consumption and the exhaust gas emission further decrease.

The motor generator 3 controls the compressor 16 of the air conditioner until the SOC falls below a predetermined level.
Instead of driving the air conditioner, the compressor 16 of the air conditioner may be driven by the motor generator 3 until the elapsed time from the start of driving by the motor generator 3 reaches a predetermined time. In FIG. 5, T
What is indicated by M is the predetermined time.

[0034]

According to the invention described in each claim, the engine is automatically stopped under predetermined engine stop conditions,
In a vehicle with an air conditioner having an engine automatic stop automatic restart device that automatically restarts the engine with battery power under predetermined engine restart conditions, when the engine is automatically stopped when there is a cooling request by the air conditioner, The driving of the compressor of the air conditioner is stopped, and the driving of the compressor is restarted after a predetermined period has elapsed. Therefore, even if the automatic stop is performed when there is a cooling request from the air conditioner, the operation of the air conditioner's compressor is stopped until a predetermined period elapses. During this time, energy is required to operate the air conditioner's compressor. Since it is not consumed, deterioration of fuel efficiency and exhaust gas is suppressed as a result.

In particular, in the case of claim 4, after a predetermined period has elapsed, the compressor of the air conditioner is first driven by the battery power as long as the battery has enough power, and the engine is started after the battery has run out of power. Since the engine is restarted and the compressor is driven by the engine, even if a predetermined period has elapsed, the engine is not restarted immediately, so that it is possible to stop fuel consumption and exhaust gas emission for a longer time. it can.

[Brief description of the drawings]

FIG. 1 is a flowchart of control according to a first embodiment of the present invention.

FIG. 2 is a system configuration diagram of each embodiment.

FIG. 3 is a time chart for explaining the operation of the first embodiment.

FIG. 4 is a flowchart of control according to a second embodiment.

FIG. 5 is a time chart for explaining the operation of the first embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Engine 2 ... Automatic transmission 3 ... Motor generator 4 ... Inverter 5 ... Battery 7 ... Controller 16 ... Air conditioner compressor 40 ... Ecolan switch 42 ... Air conditioner switch 44 ... Shift lever 45 ... Shift position sensor 46 ... Engine automatic stop Indicator 47 ... Engine cooling water temperature sensor 48 ... Engine automatic stop non-execution indicator 49 ... Engine rotation speed sensor 50 ... Vehicle speed sensor 51 ... Foot brake sensor 52 ... Hand brake sensor 54 ... Accelerator opening sensor R ... Deceleration mechanism

Claims (5)

[Claims] 1. A control device for an air-conditioned vehicle having an automatic engine stop automatic restart device for automatically stopping an engine under predetermined engine stop conditions and automatically restarting the engine under predetermined engine restart conditions. When the cooling request by the air conditioner and the automatic stop of the engine overlap, the driving of the compressor of the air conditioner is stopped, and the driving of the compressor is not restarted until a predetermined period has elapsed. 2. The control device according to claim 1, wherein the predetermined period is a period from when the driving of the compressor is stopped to when the occupant feels discomfort associated with stopping the cooling. 3. The control device according to claim 1, wherein the engine is restarted when a predetermined period elapses after the driving of the compressor is stopped, and the driving of the compressor is restarted by the restarted engine. 4. A compressor of the air conditioner can be driven by battery power, and after a predetermined period of time has elapsed after driving of the compressor is stopped, the compressor is operated by battery power as long as the charged state of the battery is equal to or higher than a predetermined level. 2. The control device according to claim 1, wherein the control device is driven, and when the drive voltage falls below a predetermined level, the engine is restarted to switch to driving by the engine. 5. A control device for a vehicle with an air conditioner having an automatic engine stop automatic restart device for automatically stopping an engine under predetermined engine stop conditions and automatically restarting the engine under predetermined engine restart conditions. If the request for cooling by the air conditioner and the automatic stop of the engine overlap, the driving of the compressor of the air conditioner is stopped, and the difference between the target compartment temperature set by the occupant and the actual compartment temperature is smaller than a predetermined value. A control device for restarting the operation of the compressor of the air conditioner when it becomes larger.