JP3572868B2 - Vehicle control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To intermittently perform an operation such as changing a steering wheel to a state immediately before the top of a vehicle by performing control so as to maintain the operation of a motor when the state of a vehicle immediately before its stop is determined and a state for maintaining the operation of the motor is determined. SOLUTION: A hybrid vehicle controller employing both of an internal combustion engine 1 and an electric motor 2 as motors perform the stop control of the internal combustion engine at the time of stopping a vehicle for reducing the amount of fuel consumption. In this case, by a microcomputer 10, determination is made as to whether the steering wheel operation angle of a hybrid vehicle based on the output of a steering sensor 12 is, for example 180 deg. or higher and whether a timer counting time is within, for example 30 seconds or not, and If YES, the changing of the steering wheel in a parking lot is determined and idling control is performed by the internal combustion engine 1. On the other hand, if NO, a stop by a traffic signal or the like is determined and the internal combustion engine 1 is stopped.

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a vehicle control device that uses an internal combustion engine, an electric motor, or both an internal combustion engine and an electric motor as a prime mover.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, for example, among vehicle control devices, there is a hybrid vehicle control device that employs both an internal combustion engine and an electric motor as prime movers, in which the electric motor is controlled as an auxiliary to the internal combustion engine.
[0003]
[Problems to be solved by the invention]
However, in the case of the above control device, if the stop control of the internal combustion engine is performed when the hybrid vehicle is stopped in order to reduce the fuel consumption, the feeling is deteriorated when the internal combustion engine is stopped and when it is started.
Specifically, if the internal combustion engine is not started immediately at the time of its start, the start of the hybrid vehicle is delayed, causing a problem that response is poor.
[0004]
In addition, for example, when parking a hybrid vehicle in a parking lot, the steering wheel is often turned back before the internal combustion engine is stopped. In this case, if the internal combustion engine stops every time the hybrid vehicle stops, there occurs a problem that the steering wheel cannot be quickly turned back.
In consideration of the above, the operation of the driver when starting and stopping the hybrid vehicle was examined.
[0005]
For example, when a hybrid vehicle stopped at an intersection or the like starts, the driver normally steps on the foot brake of the hybrid vehicle or applies the parking brake prior to starting the internal combustion engine. .
When a hybrid vehicle is parked in a parking lot, the driver frequently operates a manual transmission or a steering wheel of the hybrid vehicle when turning the steering wheel.
[0006]
In view of the above, an object of the present invention is to provide a vehicle control device that reads a driver's intention at the time of starting a vehicle and starts the internal combustion engine quickly.
It is another object of the present invention to provide a vehicle control device that reads the driver's intention when the vehicle stops and maintains the operation of the internal combustion engine as necessary.
[0007]
[Means for Solving the Problems]
In order to solve the above problem, according to the first to fifth aspects of the present invention, the operating state determining means determines whether the operating state of the prime mover should be maintained based on the operating state of the steering wheel of the vehicle by the driver. Judgment is made. Further, the immediately before stop state determination means determines whether or not the vehicle is in a state immediately before stop.
[0008]
When the immediately preceding stop state determining means determines that the vehicle is in the immediately preceding stop state, and when the operating state determining means determines that the operating state of the prime mover should be maintained, the control means maintains the operation of the prime mover. To control.
Thus, even when the driver performs an operation such as turning the steering wheel immediately before the vehicle stops, the internal combustion engine continues to operate. Therefore, a good feeling can be ensured even when the vehicle stops.
[0009]
Here, according to the third aspect of the invention, the braking means brakes or releases the driving wheels in accordance with the operation. Further, the start determination means determines whether or not the engine is to be started based on the shift operation of the manual transmission and the operation of the braking means. Then, the control means controls the start of the prime mover based on the determination of the starting state by the start determination means.
[0010]
Thus, the prime mover is started based on an operation indicating the driver's intention to start. Therefore, the vehicle can be started quickly, leading to an improvement in the feeling.
Further, according to the invention described in claim 4, the gradient detecting means detects a road surface gradient of a traveling road surface of the vehicle. Road surface determination means determines whether the vehicle is traveling uphill or downhill based on the detected road surface gradient. Further, the braking amount detecting means detects the braking amount by the braking means.
[0011]
Then, when the starting determination means determines that the road surface gradient determination means has determined that the vehicle is going uphill, if the detected braking amount is less than the first corrected braking amount that has been corrected to be larger than this, it is determined that the prime mover is to be started. Further, when the detected braking amount is smaller than the second corrected braking amount that is corrected to be smaller than this when the road gradient determining unit determines that the vehicle is going downhill, it is determined that the prime mover is to be started.
[0012]
Accordingly, when the vehicle is stopped on the uphill, the prime mover can be started quickly based on the determination of the above-mentioned start determination means, while reliably preventing the vehicle from moving downward on the uphill. Further, when the vehicle is stopped on a downhill, the prime mover can be started quickly based on the determination of the above-mentioned start determination means, while improving the fuel efficiency of the vehicle.
[0013]
According to the fifth aspect of the present invention, the start determining means corrects the detected braking amount to be larger or smaller than the first or second corrected braking amount according to the detected road surface gradient. And
As a result, the first or second corrected braking amount becomes a value that matches the gradient of the uphill or downhill, and the operational effect of the invention according to claim 4 can be further improved.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram of a control device for a hybrid vehicle according to the present invention.
The hybrid vehicle includes an internal combustion engine 1. The internal combustion engine 1 is coaxially connected at an output shaft thereof to an input shaft of a manual transmission 4 via an electric motor 2 and a dry clutch 3. Here, the internal combustion engine 1 operates by being supplied with fuel from a fuel injection device 1a (hereinafter, referred to as EFI1a) under the control of a microcomputer 10 described later.
[0015]
The clutch 3 transmits the rotational torque of the internal combustion engine 1 and the electric motor 2 to the manual transmission 4 by the engagement. The clutch 3 shuts off the transmission of the rotational torque of the internal combustion engine 1 and the electric motor 2 to the manual transmission 4 due to the disengagement. The output shaft of the manual transmission 4 is connected to both left and right drive wheels 6 via a differential gear 5.
The clutch 3 is controlled by a clutch control device 7. The drive of the electric motor 2 is controlled by the inverter 8 based on the electric power from the main battery 9.
[0016]
The water temperature sensor 1b detects a cooling water temperature of a water temperature cooling system of the internal combustion engine 1. The intake air temperature sensor 1c detects a temperature of an intake air flow into the intake pipe of the internal combustion engine 1 (hereinafter, referred to as an intake air temperature). The throttle position sensor 1d detects the opening of the throttle of the internal combustion engine 1. The rotation sensor 1e detects the rotation speed of the internal combustion engine 1. The detection outputs of the water temperature sensor 1b, the intake temperature sensor 1c, the throttle position sensor 1d, and the rotation sensor 1e are used for controlling the EFI 1a.
[0017]
The clutch stroke sensor 7a detects the engagement state of the clutch 3. The rotation sensor 17 detects the rotation speed of the output shaft of the manual transmission 4. The shift sensor 16 detects a shift position of the manual transmission 4. Voltage sensor 9 a detects a terminal voltage of main battery 9. Current sensor 9 b detects a current from main battery 9. The detection outputs of the voltage sensor 9a and the current sensor 9b are used to calculate the state of charge of the main battery 9 (hereinafter referred to as SOC).
[0018]
The accelerator switch 11 detects whether or not the accelerator pedal of the hybrid vehicle is depressed. An accelerator sensor 12 detects an amount of depression of an accelerator pedal of the hybrid vehicle. The brake switch 13 detects the presence or absence of a foot brake operation of the hybrid vehicle. The brake sensor 14 detects an operation amount of the foot brake.
[0019]
The parking brake switch 15 detects whether the parking brake has been operated. The rotation sensor 17 detects the vehicle speed of the hybrid vehicle according to the rotation speed of the output shaft of the manual transmission 4. The accelerator switch 11, the brake switch 13, and the parking brake switch 15 are turned on by the operation.
The microcomputer 10 executes a computer program according to the flowcharts shown in FIGS. During this execution, the microcomputer 10 performs various arithmetic processes based on the outputs of the switches and sensors.
[0020]
In this arithmetic processing, the output of the fuel injection amount control signal to the injector of the internal combustion engine 1, the output of the throttle opening control signal to the throttle actuator (controls the throttle opening) of the internal combustion engine 1, and the motor to the inverter 8 For example, an output of a field current control signal for controlling the output torque is performed.
Hereinafter, the operation of the above embodiment will be described. When the ignition switch IG of the hybrid vehicle is turned on before the hybrid vehicle starts running, the microcomputer 10 is supplied with power from the auxiliary battery 10a and starts executing the computer program according to the flowchart of FIG.
[0021]
First, in steps 101, 102, and 103, the states of the start switch 19a, the foot brake switch 13, the parking brake switch 15, and the shift sensor 16 of the internal combustion engine are determined to prevent runaway when the hybrid vehicle starts.
Here, the determination in step 103 becomes YES only when the shift position of the manual transmission 4 is in the neutral range N in a brake operation state by at least one of the foot brake and the parking brake.
[0022]
Accordingly, the computer program proceeds to the processing of the next subroutine 104 (see FIGS. 2 and 4) for starting and controlling the internal combustion engine 1.
Internal combustion engine start control processing
When the disengagement state of the clutch 3 is detected by the clutch stroke sensor 7a, a determination of YES is made in step 201 of FIG. Then, in step 202, the starting process of the electric motor 2 is performed. Thereby, the electric motor 2 outputs the starting torque to start the internal combustion engine 1.
[0023]
Accordingly, the rotation speed Ne of the internal combustion engine 1 becomes, for example, 600 rpm. p. m. Is exceeded, the determination in step 203 becomes YES. Then, in step 204, an idling control process of the internal combustion engine 1 is performed. Specifically, fuel is injected from an injector of the internal combustion engine 1 under a fuel injection control process for idling the EFI 1a.
[0024]
At this time, the increase correction at the time of starting is not performed as in a normal gasoline-powered vehicle. This is because a normal gasoline-powered vehicle is driven by a starter and has a starter rotation speed of 100 to 200 rpm. p. m. It is difficult to start without increasing the amount. However, in the case of the electric motor mounted on the hybrid vehicle, the electric motor 2 has a sufficient output as compared with the starter, so that the electric motor 2 alone is used to increase the idling speed. Because you can do it.
[0025]
After the start of the internal combustion engine 1, the rotation speed Ne temporarily increases. For this reason, the rotation speed Ne, for example, 1000 r. p. m. Is exceeded, YES is determined in step 205, and in step 206, the electric motor 2 is stopped. Therefore, the electric motor 2 stops outputting the driving torque, and idling of only the internal combustion engine 1 is performed.
When the start of the internal combustion engine 1 is completed, the hybrid vehicle is ready for traveling. For this reason, start control of the hybrid vehicle is performed. The determination of the start of the hybrid vehicle is made in steps 105, 106, and 107 (see FIG. 2) based on the operation states of the manual transmission 4, the foot brake, the parking brake, and the accelerator.
[0026]
When the manual transmission 4 is shifted to a shift position other than the neutral range N, that is, any of the low range L, the drive range D, and the reverse range R, the operation of the parking brake or the foot brake is released, and the accelerator is operated. The determination at 107 is YES. Therefore, the computer program shifts to the half-clutch control subroutine 108 (see FIGS. 2 and 5).
[0027]
Half clutch control processing
First, when the accelerator is operated and the parking brake and the foot brake are not operated, the determination of step 301 in FIG. 5 is YES and the determination of step 302 is NO. . If NO is determined in step 301 or YES is determined in step 302, the clutch control device 7 determines in step 303 based on the determination that the driver of the hybrid vehicle has no intention to start. The clutch 3 is disengaged.
[0028]
As described above, when the determination of NO is made in step 302, the motor torque of the motor 2 is multiplied by a value obtained by multiplying the accelerator opening calculated based on the output signal of the accelerator sensor 12 by the proportionality constant K1 in step 304. It is calculated as a value to which a later-described torque correction amount is added.
If YES is determined in step 305 to increase the accelerator opening, in step 306, the clutch control device 7 is controlled so that the clutch 3 is gradually engaged. Accordingly, when the rotation speed Ne decreases, a determination of YES is made in step 307, and in step 308, the torque correction amount is increased.
[0029]
On the other hand, if NO is determined in step 305 to decrease the accelerator opening, in step 309, the clutch control device 7 is controlled so that the clutch 3 is gradually disengaged. Accordingly, if the rotation speed Ne increases, the determination in step 310 becomes YES, and in step 311 the torque correction amount is reduced.
When the processing in step 308 or step 311 is completed as described above, in step 312, the presence or absence of the engaged state of the clutch 3 is determined based on the output of the clutch stroke sensor 7a.
[0030]
Here, if the clutch 3 is engaged, the determination in step 312 becomes YES.
Then, the presence or absence of the accelerator operation is determined again in step 109 of FIG. If the accelerator has been operated, the determination in step 109 becomes YES, and a torque cooperative control subroutine 110 (see FIGS. 3 and 6) for the internal combustion engine 1 and the electric motor 2 and a clutch control subroutine for a shift operation of the manual transmission 4 The computer program sequentially shifts to 111 (see FIGS. 3 and 7).
[0031]
Torque cooperative control processing of internal combustion engine and electric motor
In the subroutine 110 of FIG. 6, in step 401, the torque distribution between the internal combustion engine 1 and the electric motor 2 is determined based on the discharge capacity of the main battery 9.
Here, for example, when the main battery 9 is a lead battery, as shown in the graph of FIG. 11A, when the SOC exceeds about 70%, the charging efficiency of the main battery 9 is reduced. Has been clarified from unit tests of lead batteries and the like.
[0032]
When the charging efficiency decreases in this manner, energy loss due to charging of the main battery 9 increases, and fuel efficiency of the hybrid vehicle deteriorates. Conversely, when the SOC decreases, as shown in the graph of FIG. 11B, the terminal voltage drop of the main battery 9 increases, and the discharge power decreases.
Therefore, when the main battery 9 is a lead battery, its SOC is optimally controlled at around 50 to 70%.
[0033]
When the main battery 9 is not a lead battery, the SOC control range is determined from the battery characteristics.
Hereinafter, the torque control of the internal combustion engine 1 for maintaining the SOC at around 50 to 70% will be described with reference to the graph of FIG. In the graph of FIG. 12, the relationship between the rotation speed Ne of the internal combustion engine 1 and the net average effective pressure P is shown by the relationship between the maximum effective pressure of the internal combustion engine 1 and the constant fuel consumption rate curve. Further, on this graph, the respective operating regions L1, L2, L3 of the internal combustion engine 1 are specified in relation to the various quantities in the graph. The graph of FIG. 12 is stored in the ROM of the microcomputer 10 as map data in advance.
[0034]
First, when the SOC exceeds 70%, the determination in step 401 becomes YES, and in step 405, the operation region L3 in the graph of FIG. 12 is selected. As a result, control is performed so that the torque control region of the internal combustion engine 1 is minimized.
If the SOC is 70% or less and exceeds 50%, a determination of NO is made in step 402 after a determination of NO in step 401. Accordingly, in step 404, the operation region L2 in the graph of FIG. 12 is selected. As a result, control is performed so that the torque control region of the internal combustion engine 1 is in the intermediate region.
[0035]
If the SOC is 50% or less, the determination in step 402 is YES, and in step 403, the operation region L1 in the graph of FIG. 12 is selected. As a result, control is performed so that the torque control region of the internal combustion engine 1 is maximized.
By performing the torque control of the internal combustion engine 1 under the control of the torque control region of the internal combustion engine 1, the SOC of the main battery 9 can be maintained at around 50 to 70%.
[0036]
Thereafter, in step 406, the motor torque of the motor 2 is calculated and output as a value obtained by subtracting the output torque of the internal combustion engine 1 from the product of the accelerator operation amount as the torque command and the proportionality constant K3.
Clutch control processing during shift operation of a manual transmission
Here, a cooperative control process between the clutch 3 and the electric motor 2 is performed with the shift operation of the manual transmission 4. That is, cooperative processing of the on / off control of the clutch 3 and the control of the electric motor 2 during the shift operation of the manual transmission 4 is performed.
[0037]
In step 501, it is determined whether the shift position of the manual transmission 4 is in the neutral range N based on the detection output of the shift sensor 16. This is because in the case of the manual transmission 4, the shift operation always passes through the neutral range N when changing gears of the manual transmission 4.
If the determination in step 501 becomes YES because the neutral range N has been reached, in step 502, the clutch control device 7 is controlled to disengage the clutch 3.
[0038]
Then, in step 503, the inverter 8 is controlled so as to stop the electric motor 2. As a result, the output torque of the electric motor 2 becomes zero. Next, in step 504, the internal combustion engine 1 is idling-controlled.
In the next step 505, when the shift operation of the manual transmission 4 to a range other than the neutral range N is completed, a determination of NO is made. Then, at step 506, the inverter 8 is controlled so as to increase the torque of the electric motor 2. Here, when the rotation speed Ne is equal to or greater than the product of the output shaft rotation speed Nt of the manual transmission 4 and the speed ratio It at that time, the determination in step 507 becomes YES.
[0039]
Accordingly, in step 508, the inverter 8 is controlled so as to stop the increase in the torque of the electric motor 2, and the clutch control device 7 is controlled so that the clutch 3 is engaged. As a result, the shock generated when the clutch 3 is engaged can be reduced.
If the accelerator operation is not performed in step 109 (see FIG. 3), a determination of NO is made based on the output of the accelerator sensor 12. As a result, the computer program shifts to the processing of the brake control subroutine 112 (see FIGS. 3 and 8) based on the determination that the command is the deceleration command by the brake operation of the foot brake.
[0040]
Brake control processing
First, at step 601, the EFI 1a is controlled so as to cut off the fuel of the internal combustion engine 1. At this time, if the brake operation by the foot brake is performed, YES is determined in step 602, and in the next step 603, the inverter 8 is controlled so as to perform the regenerative brake control of the electric motor 2.
[0041]
Specifically, the output torque of the electric motor 2 is calculated by the product of the brake operation amount of the foot brake and the proportional constant K2 based on the detection output of the brake sensor 14.
If the foot brake operation has not been performed in step 602, it is determined that the command is an engine brake command for a normal gasoline vehicle based on the determination of NO. It is controlled by the inverter 8.
[0042]
In step 113 (see FIG. 3), when the accelerator operation is performed during deceleration of the hybrid vehicle, and YES is determined based on the output of the accelerator sensor 12, the process of the torque cooperative control subroutine 110 is performed again. . Here, acceleration control of the hybrid vehicle is performed.
When the accelerator operation is not performed and the hybrid vehicle is decelerating as it is, the determination in step 113 is NO. Then, in step 114, if the shift position of the manual transmission 4 is in a range (low range L or reverse range R) other than the drive range D, it is determined to be NO based on the output of the shift sensor 16.
[0043]
At this time, the vehicle speed of the hybrid vehicle (hereinafter, referred to as vehicle speed V) is calculated based on the detection output of the rotation sensor 17, and if it is, for example, 10 km / h or less, the determination in step 116 is NO.
If it is the drive range D, the determination in step 115 is made after the determination in step 114 is YES. At this time, if the vehicle speed V is, for example, 16 km / h or less, the determination in step 115 is NO.
[0044]
Accordingly, in step 117, the clutch control device 7 is controlled so as to disengage the clutch 3. Then, in step 118, the internal combustion engine 1 is placed in idling control.
If the determination in step 115 is YES, the process returns to the brake control subroutine 112 to continue the brake control. This is because the relationship between the idling rotational speed of the internal combustion engine 1 and the vehicle speed V differs depending on the gear ratio of the manual transmission 4. Further, if the clutch 3 is disengaged at a high vehicle speed in a drive range D which is a high speed gear of the manual transmission 4, and the clutch 3 is disengaged at a low vehicle speed in a low range L and a reverse range R which are low speed gears, the torque of the internal combustion engine 1 must be increased. This is because the fluctuation is transmitted to the wheels of the hybrid vehicle, and the vibration of the hybrid vehicle increases, which causes discomfort to the occupants.
[0045]
If it is determined as YES in step 119 based on the output of the accelerator sensor 12 under the operation of the accelerator, the half-clutch control of the clutch 3 is performed in the half-clutch control subroutine 108.
If the determination in step 119 is NO, the vehicle speed V calculated based on the detection output of the rotation sensor 17 is, for example, 2 km / h or less, that is, just before the stoppage of the hybrid vehicle, and it is determined in step 120 that The determination is YES. Next, in step 121, if the temperature of the cooling water of the internal combustion engine 1 is lower than, for example, 50 ° C., it is determined to be NO based on the output of the water temperature sensor 1b because the warming up of the hybrid vehicle is insufficient. Therefore, the idling control of the internal combustion engine 1 is continued.
[0046]
Thereafter, if the determinations of both steps 120 and 121 are YES based on the determination of NO in step 119, the internal combustion engine stop control subroutine 122 (FIG. 3) is determined based on the determination that the internal combustion engine 1 has been warmed up. 9) and the internal combustion engine restart control subroutine 123 (see FIGS. 3 and 10).
In the internal combustion engine stop control subroutine 122, a process of determining whether to stop the internal combustion engine 1 is performed. In the internal combustion engine restart control subroutine 123, the restart control of the internal combustion engine 1 is performed in preparation for the restart of the hybrid vehicle. The details will be described below.
[0047]
Internal combustion engine stop control processing
In step 701a of FIG. 9, a start process of a timer built in the microcomputer 10 is performed. Therefore, the timer starts counting by the reset start.
In step 701, it is determined whether the steering wheel of the hybrid vehicle has been operated, for example, for 180 seconds or more for 30 seconds. This is for the following reason.
[0048]
That is, when a hybrid vehicle enters a parking lot or the like, the steering wheel is often operated by turning right or left. Moreover, the steering wheel operation when the hybrid vehicle does not normally make a right turn or a left turn, for example, the operation of the steering wheel when traveling on a road curve, rarely exceeds 180 °.
For this reason, the time required for the hybrid vehicle to stop at a predetermined position such as a parking lot is set to 30 seconds, and then it is determined whether or not the steering wheel has been operated by 180 ° or more. Note that the time of 30 seconds may be appropriately changed.
[0049]
When the operation angle of the steering wheel of the hybrid vehicle based on the output of the steering sensor 12 is 180 ° or more and the time counted by the timer is within 30 seconds, YES is determined in step 701. That is, YES is determined in step 701 based on the determination that the steering wheel is turned back in the parking lot.
[0050]
After such a determination, in step 703, the internal combustion engine is idling-controlled. Then, the process of step 808 of the subroutine 123 in FIG. 10 is performed. At this time, if the accelerator sensor 12 is turned on by the accelerator operation, the determination in step 808 becomes YES.
Thus, when the steering wheel is turned back when the hybrid vehicle is stopped in a parking lot or the like, the internal combustion engine 1 does not stop.
[0051]
On the other hand, if the determination in step 701 is NO, the EFI 1a is controlled to stop the internal combustion engine in step 702 based on the determination that the hybrid vehicle is stopped by a traffic signal or the like.
As described above, on the assumption that the hybrid vehicle is just before stopping based on the determination of YES in step 120, the determination of YES in step 701, that is, the determination that the steering wheel of the hybrid vehicle is in the turning state is performed. , The internal combustion engine 1 is maintained in the operating state without stopping.
[0052]
As a result, the internal combustion engine 1 does not stop at the time of turning of the steering wheel prior to parking of the hybrid vehicle in a parking lot or the like, so that the turning can be smoothly performed with a good feeling. It is to be noted that such an operation and effect is achieved under the so-called economy control in consideration of the improvement of the fuel efficiency of the internal combustion engine 1 as described above.
Internal combustion engine restart control processing
If the shift position of the manual transmission 4 is in the neutral range N in step 801 in FIG. 10, a determination of YES is made. This is for the following reason.
[0053]
The driver shifts the manual transmission 4 to the neutral range N immediately before stopping the hybrid vehicle. Further, it is considered that the driver shifts the manual transmission 4 to the drive range D, the low range L, or the reverse range R and starts when the hybrid vehicle starts in such a state.
Therefore, first, it is determined in step 801 whether or not the neutral range N is set.
[0054]
If the driver operates the manual transmission 4 in a range other than the neutral range N after making a determination of YES in step 801, a determination of NO is made in step 802. Accordingly, in the internal combustion engine start control subroutine 807, the electric motor 2, the clutch 3, and the EFI 1a are controlled so as to start the internal combustion engine 1.
[0055]
Specifically, the electric motor 2 is started by the inverter 8, the clutch 3 is disengaged by the clutch control device 7, and the fuel injection of the injector of the internal combustion engine 1 is controlled by the EFI 1 a. Thus, the internal combustion engine 1 starts. Such a state is maintained by the determination of NO in step 808 based on the accelerator switch 11 being turned on.
[0056]
If the determination in step 802 is YES, in step 803, the SOC of shift main battery 9 is calculated from the outputs of voltage sensor 9a and current sensor 9b. When the SOC is less than 50%, the internal combustion engine 1 is subjected to a start process in an internal combustion engine start control subroutine 807 to prevent overdischarge of the main battery 9.
[0057]
If the determination in step 801 is NO, that is, if the shift position of the manual transmission 4 is not in the neutral range N, the driver stops only by the brake operation in the shift position before the stop of the hybrid vehicle. Is determined to be. Then, after determining NO in step 804, in step 805, the hydraulic pressure detection output of the brake pressure sensor provided in the brake hydraulic system of the foot brake must be smaller than a predetermined hydraulic pressure corresponding to the brake operation amount, for example, 0.3 MPa. In this case, it is determined that the driver intends to start the hybrid vehicle.
[0058]
Therefore, in the internal combustion engine start control subroutine 807, the start control of the internal combustion engine is performed in the same manner as described above.
If it is determined in step 805 that the brake hydraulic pressure is equal to or higher than 0.3 MPa and the determination is NO, it is determined in step 806 whether the SOC is lower than 50%. If the determination in step 806 is YES, in order to prevent overdischarge of the main battery 9, in the internal combustion engine start control subroutine 807, start control of the internal combustion engine 1 is performed as described above.
[0059]
If NO is determined in step 806, the process returns to step 804. Here, if the shift position of the manual transmission 4 is in the neutral range N, the driver shifts the manual transmission 4 to the neutral range N while the hybrid vehicle is stopped, and when the vehicle starts moving, the drive range D, the low range L, and the reverse range. It is determined that the vehicle shifts to R and starts. Therefore, the determination process of step 802 is performed after the determination of YES in both steps 804.
[0060]
As described above, when the internal combustion engine 1 is operated, YES is determined based on the accelerator switch 11 being turned on under the operation of the accelerator in step 808, and the processing of the latter half clutch control subroutine 108 is performed. Thus, the hybrid vehicle is started under the half-clutch control of the clutch 3 on the assumption that the driver intends to start.
[0061]
When the ignition switch IG is turned off, it goes without saying that the internal combustion engine 1 and the electric motor 2 stop in any state.
13 and 14 show a modification of the above embodiment.
In this modification, the gradient sensor 19b is further connected to the microcomputer 10 described in the above embodiment. This gradient sensor 19b detects the gradient of the traveling road surface of the hybrid vehicle.
[0062]
Further, the internal combustion engine start control subroutine 123 (see FIG. 10) described in the above embodiment is changed to the respective steps 804a, 805a to 805c in step 805 as shown in the flowchart of FIG.
If it is determined in step 804a that the vehicle is traveling uphill based on the detection output of the gradient sensor 19b, then in step 805a, the detected brake hydraulic pressure of the brake hydraulic sensor is multiplied by a value obtained by multiplying the detected road surface gradient of the gradient sensor 19b by a proportional constant K4. The value is compared with a value obtained by adding the predetermined oil pressure of 0.3 MPa (hereinafter, referred to as a first correction oil pressure).
[0063]
Accordingly, the first corrected hydraulic pressure can make the hydraulic pressure determination value in step 805a higher than that in the above-described embodiment when the traveling road surface is on an uphill.
Therefore, a decrease in the braking amount due to the driver's braking operation can be determined earlier in step 805a. As a result, the internal combustion engine 1 can be quickly operated in the internal combustion engine start control subroutine 807 based on the determination of YES in step 805a to prevent the hybrid vehicle from moving backward.
[0064]
If it is determined in step 804a that the vehicle is going downhill based on the detection output of the gradient sensor 19b, then in step 805b, the detected brake oil pressure of the brake oil pressure sensor is multiplied by a proportional constant K4 to the detected road surface gradient of the gradient sensor 19b. The value is compared with a value obtained by subtracting the value from the predetermined oil pressure of 0.3 MPa (hereinafter, referred to as a second correction oil pressure).
Thus, the second corrected hydraulic pressure can make the hydraulic pressure determination value in step 805b lower than that in the above-described embodiment when the traveling road surface is on a downhill.
[0065]
Therefore, a decrease in the braking amount due to the driver's braking operation can be determined later in step 805a. As a result, based on the determination of YES in step 805b, the internal combustion engine 1 is operated later in the internal combustion engine start control subroutine 807, and the improvement of the fuel efficiency of the hybrid vehicle can be ensured.
When it is determined in step 804a that the traveling road surface of the hybrid vehicle is flat based on the detection output of the gradient sensor 19b, the same processing as that after the determination of YES in step 805 in the above embodiment is performed.
[0066]
The present invention is not limited to a hybrid vehicle, but may be applied to a vehicle using only an internal combustion engine as a prime mover or a vehicle using only an electric motor as a prime mover. In this case, the present invention may be applied to control of a prime mover that does not consider the economy control, without being limited to control of the prime mover taking into account the economy control of the vehicle as in the above-described embodiment.
[0067]
Further, in the embodiment of the present invention, it is determined whether or not an alternate shift operation between the drive range D or the low range L and the reverse range R of the manual transmission 4 has been performed instead of the determination criterion in Step 701 of FIG. Even if it is adopted and implemented as a reference, the same operation and effect as the above embodiment (operation and effect by the processing of step 703) can be secured.
[0068]
Further, in implementing the present invention, as the determination criterion in each of the steps 805a and 805b in FIG. 14, a fixed value is adopted for each of the ascending gradient and the descending gradient irrespective of the detection output of the gradient sensor 19b. You may.
In practicing the present invention, the manual transmission described in the above embodiment has two forward gears. However, even if the number of gears increases, a vehicle speed threshold value is determined in accordance with the shift position (steps 115 and 116). Needless to say, it is only necessary to change the criterion for determining the rotational speed Ne of the internal combustion engine during the shift operation (step 507).
[Brief description of the drawings]
FIG. 1 is a schematic block diagram showing one embodiment of the present invention.
FIG. 2 is a first part of a flowchart showing the operation of the microcomputer of FIG. 1;
FIG. 3 is a second half of a flowchart showing the operation of the microcomputer of FIG. 1;
FIG. 4 is a flowchart showing details of an internal combustion engine start control subroutine of FIG. 2;
FIG. 5 is a flowchart showing details of a half-clutch control subroutine of FIG. 2;
FIG. 6 is a flowchart showing details of a torque cooperative control subroutine of the internal combustion engine and the electric motor of FIG. 3;
FIG. 7 is a flowchart showing details of a clutch control subroutine at the time of operating the manual transmission shown in FIG. 3;
FIG. 8 is a flowchart showing details of a brake control subroutine of FIG. 3;
FIG. 9 is a flowchart showing details of an internal combustion engine stop control subroutine of FIG. 3;
FIG. 10 is a flowchart showing details of an internal combustion engine restart control subroutine of FIG. 3;
FIG. 11 is a graph showing the relationship between the charging efficiency and the state of charge of the main battery, and the relation between the terminal voltage and the state of discharge at the time of constant current discharge.
FIG. 12 is a graph showing a torque control region of the internal combustion engine in a relationship between a rotation speed of the internal combustion engine and a net average effective pressure.
FIG. 13 is a main part block diagram showing a modification of the embodiment.
FIG. 14 is a detailed flowchart of an internal combustion engine restart control subroutine executed by the microcomputer in the modified example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Internal combustion engine, 2 ... Electric motor, 3 ... Clutch, 4 ... Manual transmission, 6 ... Drive wheels,
7: clutch control device, 10: microcomputer,
14: brake sensor, 18: steering sensor, 19b: gradient sensor.

Claims (5)

A prime mover (1, 2) mounted on a vehicle,
A manual transmission (4) for transmitting and releasing power from the prime mover to driving wheels (6) of a vehicle by a shift operation;
A control unit (1a, 7, 8, 9, 10, 18, 703) for controlling transmission of power from the prime mover to the manual transmission and its interruption.
Operating state determining means (701) for determining whether or not the operating state of the prime mover is to be maintained based on the operating state of the steering wheel of the vehicle by the driver;
Immediately before stop state detecting means (120) for detecting whether or not the vehicle is in a state immediately before stop;
When the immediately preceding stop state determining means determines that the vehicle is in the immediately preceding stop state, and when the operating state determining means determines that the operating state of the prime mover should be maintained, the control means controls the operation of the prime mover. A vehicle control device that controls the vehicle to be maintained. The operating state determination means performs a determination that the operating state of the prime mover should be maintained based on the turning state of the steering wheel,
2. The vehicle control device according to claim 1, wherein the control unit performs control for maintaining the operation of the prime mover based on the determination and the determination that the immediately before stop state determination unit determines the immediately before stop state. Braking means for performing braking or release of the driving wheels in accordance with an operation;
Starting determination means (801, 804, 805) for determining whether or not the motor is to be started based on a shift operation of the manual transmission and an operation of the braking means;
The control device for a vehicle according to claim 1, wherein the control unit controls the start of the prime mover based on a determination that the engine is to be started by the start determination unit. Gradient detecting means (19b) for detecting a road surface gradient of a traveling road surface of the vehicle;
Road surface determining means (804a) for determining whether the vehicle is going uphill or downhill based on the detected road surface gradient;
Braking amount detecting means for detecting the braking amount by the braking means,
When the starting determination unit determines that the road surface gradient determination unit determines that the vehicle is going uphill, and when the detected braking amount is less than a first corrected braking amount that has been corrected to be larger than this, it is determined that the prime mover is to be started. Further, when the road gradient determining means determines that the vehicle is going downhill, if the detected braking amount is less than a second corrected braking amount that is corrected to be smaller than this, it is determined that the prime mover is to be started. The vehicle control device according to claim 3, wherein: The said starting determination means correct | amends the said detected braking amount larger or smaller than this according to the said detected road surface gradient, and makes it the said 1st or 2nd corrected braking amount. Vehicle control device.

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