JP2010149682A - Device and method for controlling engine start - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device and a method for controlling engine start capable of shortening time required for switching from 2WD to 4WD. <P>SOLUTION: An engine control means 50 for controlling a driving state of an engine 1 for driving front wheels stops the engine 1 during driving a motor 8 for driving rear wheels according to driving force required by a driver, and further starts the stopped engine 1 during the operation of the ABS control means 28 when an ABS control means 28 for controlling breaking force so as to suppress the lock of the front wheels and rear wheels is operated in a state where the engine 1 is stopped in driving the motor 8. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an engine start control device and a start control method for controlling start of an engine stopped when a driving state of a vehicle is switched to a two-wheel driving state.

Conventionally, as a device that switches between a four-wheel drive state in which front and rear wheels are driven and a two-wheel drive state in which one of the front and rear wheels is driven according to the behavior of the vehicle during braking, for example, as described in Patent Document 1 There is a driving state switching device. In the following description, the four-wheel drive state is described as “4WD”, and the two-wheel drive state is described as “2WD”.
The driving state switching device described in Patent Document 1 operates a known antilock brake system (hereinafter, “ABS”) device during braking at 4WD when the lateral acceleration of the vehicle body is less than a set value. In the state, the driving state of the vehicle is switched from 4WD to 2WD. When the driving state of the vehicle is switched from 4WD to 2WD, the driving force supply to one of the front and rear wheels is stopped.
JP-A-6-328965

By the way, there is a vehicle (hereinafter referred to as “hybrid vehicle”) configured such that one of the front and rear wheels is driven by an engine and the other of the front and rear wheels is driven by a motor.
For this hybrid vehicle, when driving power supply to one of the front and rear wheels is stopped and the driving state of the vehicle is switched from 4WD to 2WD as in the driving state switching device described in Patent Document 1, the engine is It is preferable to stop. This is because it is preferable to stop the engine rather than the motor in order to obtain good fuel efficiency.
When the driving force requested by the driver (hereinafter referred to as “required driving force”) increases, such as when a slip occurs after shifting from the braking state to the traveling state by reacceleration, the vehicle is stopped. The engine is started and the driving state of the vehicle is switched from 2WD to 4WD.

However, when the engine is stopped and the driving state of the vehicle is switched from 4WD to 2WD as described above, the driving state of the vehicle cannot be switched from 2WD to 4WD until the stopped engine is started. For this reason, there may be a problem that the time from when the required driving force is required until the required driving force can be output becomes longer.
The present invention has been made paying attention to the above points, and an apparatus capable of shortening the time taken to start the stopped engine and switch the driving state of the vehicle from 2WD to 4WD, and It is an object to provide a control method.

  In order to solve the above-described problems, the present invention provides an engine for driving one of the front wheels and the rear wheels of a vehicle and a motor for driving the other of the front wheels and the rear wheels according to the driving force required by the driver. Stop while driving. Then, when the ABS control means for controlling the braking force is operated so as to suppress the locking of the front wheels and the rear wheels while the engine is stopped, the stopped engine is started during the operation of the ABS control means.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to shorten the time required from supplying the driving force to the wheels driven by the engine to supplying the driving force to the wheels driven by the engine. As a result, it is possible to shorten the time required for the vehicle to be driven from the state where the engine is stopped and the drive wheels are reduced to the state where the engine is started and the drive wheels are increased.

(First embodiment)
Hereinafter, a first embodiment of the present invention (hereinafter referred to as “the present embodiment”) will be described with reference to the drawings.
(Constitution)
First, the configuration of an engine start control device (hereinafter referred to as “start control device”) according to the present embodiment will be described with reference to FIGS. 1 to 5.
FIG. 1 is a top view of a vehicle C including the start control device of the present embodiment, and shows a schematic configuration of the vehicle C.
As shown in FIG. 1, a vehicle C including a start control device includes an engine 1, a front wheel 2, a generator 4, an inverter 6, a motor 8, a rear wheel 10, acceleration detection means 12, and a vehicle. A vehicle having a controller 14.

The engine 1 is an internal combustion engine and constitutes a drive source that drives the front wheels 2. In FIG. 1, the front wheels 2 arranged on the left and right are respectively indicated as left and right front wheels 2L and 2R.
For example, a main throttle valve and a sub-throttle valve are interposed in an intake pipe line (not shown) of the engine 1. The main throttle valve adjusts and controls the throttle opening according to the operation amount (depression amount) of the accelerator pedal 16 by the driver.
The accelerator pedal 16 outputs an information signal including the operation amount to the vehicle controller 14.

The drive shaft of the engine 1 can be connected to the left and right front wheels 2L, 2R via the clutch 18 and the transmission 20. Therefore, the engine 1 forms a drive source that drives the left and right front wheels 2L and 2R in a state where the drive shaft of the engine 1 is connected to the left and right front wheels 2L and 2R. Further, the left and right front wheels 2L, 2R form engine drive wheels driven by the engine 1.
The clutch 18 is formed by, for example, a wet multi-plate clutch, and is interposed in a driving force transmission path between the engine 1 and the left and right front wheels 2L, 2R. In this embodiment, the clutch 18 as the fastening means is a wet multi-plate clutch. However, the present invention is not limited to this, and the clutch 18 may be formed by, for example, a powder clutch or a pump-type clutch. .

Further, the clutch 18 is connected or released according to a clutch control command output by the vehicle controller 14, and switches the driving state of the vehicle C to the four-wheel driving state (4WD) or the two-wheel driving state (2WD). .
Specifically, when the clutch 18 is in the connected state, the drive shaft of the engine 1 is connected to the left and right front wheels 2L, 2R, and the drive state of the vehicle C is a four-wheel drive state. In this state, the left and right front wheels 2L and 2R and the left and right rear wheels 10L and 10R are driving wheels.

On the other hand, when the clutch 18 is released, the connection between the drive shaft of the engine 1 and the left and right front wheels 2L, 2R is released, and the drive state of the vehicle C becomes a two-wheel drive state. In this state, of the left and right front wheels 2L and 2R and the left and right rear wheels 10L and 10R, only the left and right rear wheels 10L and 10R are driving wheels.
The transmission 20 includes a transmission or the like that can change the gear ratio in a plurality of stages, and is interposed between the clutch 18 and the left and right front wheels 2L and 2R.

Front wheel speed sensors 22L and 22R are provided on the left and right front wheels 2L and 2R, respectively.
Each front wheel speed sensor 22L, 22R detects the rotational speed of the corresponding left and right front wheels 2L, 2R, and outputs an information signal including the detected rotational speed to the vehicle controller 14.
The left and right front wheels 2L, 2R are provided with front wheel brake devices 24L, 24R, respectively.
Each front wheel brake device 24L, 24R is applied to the corresponding left and right front wheels 2L, 2R from the hydraulic pressure source (not shown) by adjusting the hydraulic pressure according to the operation amount (depression amount) of the brake pedal 26. To communicate. The hydraulic pressure is adjusted according to an information signal output from the vehicle controller 14.

Here, each front wheel brake device 24L, 24R outputs an information signal including the brake fluid pressure transmitted to the corresponding left and right front wheels 2L, 2R to the vehicle controller 14 respectively. Further, the brake pedal 26 outputs an information signal including the operation amount to the vehicle controller 14.
Specifically, during normal braking, hydraulic oil whose hydraulic pressure is adjusted to the braking hydraulic pressure in accordance with the amount of operation of the brake pedal 26 is supplied to a braking piston (not shown). Then, the braking piston is applied to the left and right front wheels 2L and 2R by pressing the brake piston against the left and right front wheels 2L and 2R to be in sliding contact therewith.

On the other hand, at the time of braking in which ABS control is performed, the braking fluid pressures of the front wheel brake devices 24L and 24R are held, reduced or increased, and applied to the left and right front wheels 2L and 2R so as to suppress the locking of the left and right front wheels 2L and 2R. Control the braking force. This ABS control is performed by, for example, an inflow electromagnetic valve and an outflow electromagnetic valve (not shown) individually provided for each front wheel brake device 24L and 24R, and an inflow (not shown) provided in common for each front wheel brake device 24L and 24R. Use a solenoid valve and an outflow solenoid valve. Here, the inflow solenoid valve is a solenoid valve that is shut off during excitation. Moreover, the outflow solenoid valve is a solenoid valve that communicates during excitation.
Excitation and demagnetization of each inflow solenoid valve and outflow solenoid valve are controlled by an ABS control means 28 described later. That is, the braking operation for performing the ABS control is the operation time of the ABS control means 28. The operation of the ABS control means 28 will be described later.

Hereinafter, the state of each inflow solenoid valve and each outflow solenoid valve during braking will be described.
During normal braking, each inflow solenoid valve and each outflow solenoid valve are demagnetized.
On the other hand, when performing ABS control, the inflow solenoid valves corresponding to the left and right front wheels 2L, 2R that are in a locking tendency (the tendency to lock) are shut off to prevent the left and right front wheels 2L, 2R from being locked. The increase in braking force is suppressed as much as possible.
Even when the left and right front wheels 2L and 2R tend to lock even in the state where the above control is performed, the outflow solenoid valves corresponding to the left and right front wheels 2L and 2R are set in a communicating state, and the left and right front wheels 2L and 2R The braking force is further reduced to suppress the locking of the left and right front wheels 2L, 2R.

Hereinafter, the description returns to the vehicle C.
The generator 4 is configured to drive using the driving force from the engine 1 as a power source to generate electric power. Specifically, the rotating shaft of the generator 4 is connected to the rotating shaft of the engine 1 via the endless belt 30. As a result, a part of the rotational torque of the engine 1 is transmitted to the generator 4 via the endless belt 30, and the rotating shaft of the generator 4 is rotated at a rotational speed obtained by multiplying the rotational speed of the engine 1 by the pulley ratio. To generate electricity.

  Moreover, the generator 4 becomes a load with respect to the engine 1 according to the field current which the vehicle controller 14 adjusts, and generates electric power according to the load torque. The magnitude of electric power (generated electric power) generated by the generator 4 is determined by the magnitude of the rotational speed and the field current. The rotational speed of the generator 4 can be calculated from the rotational speed of the engine 1 based on the pulley ratio. The electric power generated by the generator 4 is supplied to and stored in the battery 32.

An inverter 6 is connected to the battery 32. The electric power generated by the generator 4 and stored in the battery 32 can be supplied to the inverter 6.
The inverter 6 converts the DC power supplied from the generator 4 into AC power such as, for example, three-phase AC and supplies it to the motor 8.
The motor 8 is formed of, for example, a field winding type synchronous motor, and includes a rotor (not shown) having a field coil and a three-phase winding (armature coil) for generating a rotating magnetic field. And a wound stator (not shown).

The motor 8 rotates by the interaction between a magnetic field generated by passing a current through a field coil of the rotor and a magnetic field generated from an armature coil wound around the stator. Thus, the motor 8 constitutes a drive source that drives the rear wheel 10. In FIG. 1, the rear wheels 10 arranged on the left and right are respectively shown as the left and right rear wheels 10L and 10R.
Further, when the rotor is rotated by an external force, the motor 8 generates an electromotive force at both ends of the armature coil due to the interaction of these magnetic fields, and performs a power generation operation. The electric power generated by the motor 8 can be supplied to the battery 32 via the inverter 6 and stored.

The drive shaft of the motor 8 is connected to the left and right rear wheels 10L and 10R via the speed reducer 34 and the differential 36.
Rear wheel speed sensors 38L and 38R are provided on the left and right rear wheels 10L and 10R, respectively.
Each of the rear wheel speed sensors 38L, 38R detects the rotational speed of the corresponding left and right rear wheels 10L, 10R, and outputs an information signal including the detected rotational speed to the vehicle controller 14.
The left and right rear wheels 10L and 10R are provided with rear wheel brake devices 40L and 40R, respectively.

  Each of the rear wheel brake devices 40L and 40R transmits the brake hydraulic pressure adjusted in accordance with the operation amount of the brake pedal 26 from the hydraulic pressure source (not shown) to the corresponding left and right rear wheels 10L and 10R, respectively. To do. Here, each rear wheel brake device 40L, 40R, like each front wheel brake device 24L, 24R, transmits an information signal including the brake fluid pressure transmitted to the corresponding left and right rear wheels 10L, 10R, respectively, to the vehicle control controller. 14 for output. In addition, since the operation | movement at the time of braking of each rear-wheel brake device 40L and 40R is the same as that of each front-wheel brake device 24L and 24R mentioned above, the description is abbreviate | omitted.

The acceleration detection means 12 includes a longitudinal acceleration / deceleration sensor (not shown) that detects acceleration and deceleration of the vehicle C in the vehicle longitudinal direction.
Further, the acceleration detection means 12 detects the acceleration and deceleration in the vehicle longitudinal direction of the vehicle C, and outputs an information signal including the detected acceleration and deceleration in the vehicle longitudinal direction to the vehicle controller 14.
The vehicle controller 14 is formed by an arithmetic processing device such as a microcomputer, for example.

Next, the configuration of the vehicle controller 14 will be described using FIGS. 2 to 4 with reference to FIG.
FIG. 2 is a block diagram showing the configuration of the vehicle controller 14.
As shown in FIG. 2, the vehicle controller 14 includes an ABS controller 28, a motor controller 42, a battery controller 44, and a 4WD controller 46. In addition, the vehicle controller 14 includes an acceleration comparison unit 48, an engine control unit 50, and a clutch control unit 52.
The ABS control means 28 operates based on information signals output from the front wheel speed sensors 22L and 22R, the rear wheel speed sensors 38L and 38R, and the brake pedal 26, and performs the above-described ABS control.

Hereinafter, the detailed configuration of the ABS control means 28 will be described with reference to FIG.
FIG. 3 is a block diagram showing the configuration of the ABS control means 28.
As shown in FIG. 3, the ABS control means 28 includes a vehicle speed calculation unit 54, a lock detection unit 56, a required braking force calculation unit 58, and a hydraulic pressure control unit 60.
The vehicle speed calculation unit 54 calculates the speed (vehicle speed) of the vehicle C based on information signals output from the front wheel speed sensors 22L and 22R and the rear wheel speed sensors 38L and 38R. Then, an information signal including the calculated vehicle speed is output to the lock detection unit 56.

  Based on the information signal output from the front wheel speed sensors 22L and 22R and the rear wheel speed sensors 38L and 38R and the information signal output from the vehicle speed calculation unit 54, the lock detection unit 56 The above-described locking tendency is detected for the wheels 10L, 10R). Then, an information signal including the detection result is output to the hydraulic pressure control unit 60, the 4WD controller 46, the engine control means 50, and the clutch control means 52. The information signal output from the lock detection unit 56 to the 4WD controller 46, the engine control means 50, and the clutch control means 52 forms an information signal indicating the operating state of the ABS control means 28. Here, the “operating state of the ABS control means 28” indicates a state where the ABS control means 28 is operating and a state where it is stopped.

Specifically, the detection of the lock tendency for each wheel is performed by comparing the vehicle speed and the rotation speed of each wheel, and if a wheel having a low rotation speed with respect to the vehicle speed is detected, it is determined that the wheel is in a lock tendency. . Then, the lock tendency of each wheel is detected based on the position of the wheel determined to have a lock tendency (front and rear, left and right of the vehicle C).
The required braking force calculation unit 58 detects the amount of operation of the brake pedal 26 by the driver based on the information signal output from the brake pedal 26. Then, based on the detected operation amount of the brake pedal 26, a braking force required by the driver (required braking force) is calculated.

The required braking force calculation unit 58 that has calculated the required braking force outputs an information signal including the calculation result to the hydraulic pressure control unit 60.
The hydraulic control unit 60 performs the above-described ABS control on the wheels that tend to be locked during braking based on the information signals output from the lock detection unit 56 and the required braking force calculation unit 58.
Specifically, during normal braking, the hydraulic pressure of the hydraulic oil corresponding to the operation amount of the brake pedal 26 is calculated based on the information signal output from the required braking force calculation unit 58. Then, an information signal including the calculated hydraulic fluid pressure is output to the front wheel brake devices 24L and 24R and the rear wheel brake devices 40L and 40R.

On the other hand, at the time of braking in which ABS control is performed, based on the information signals output from the lock detection unit 56 and the required braking force calculation unit 58, the inflow solenoid valve and the outflow solenoid valve provided in the brake device corresponding to the wheel that tends to be locked Excitation control and demagnetization control are performed. As a result, as described above, an increase in braking force is suppressed so as to avoid a wheel having a locking tendency from being locked, and the locking of the wheel having a locking tendency is suppressed.
As described above, the ABS control means 28 operates to suppress the locking of the wheels (the left and right front wheels 2L and 2R and the left and right rear wheels 10L and 10R) during braking.

Hereinafter, the description returns to the configuration of the vehicle controller 14.
The motor control means 42 inputs / outputs information signals to / from the motor 8, the inverter 6 and the 4WD controller 46, and controls the driving state of the motor 8 based on these information signals. This is control for increasing the driving force of the motor 8 in order to output a target driving force based on the operation amount of the accelerator pedal 16 input to the 4WD controller 46, for example.
The battery controller 44 inputs and outputs information signals between the battery 32 and the 4WD controller 46. These information signals are used for control of the generator 4 with respect to the remaining capacity of the battery 32 and control of the motor 8 and the engine 1 with respect to the remaining capacity of the battery 32, for example.

The 4WD controller 46 is based on information signals that are input / output between the motor control means 42, battery control means 44, ABS control means 28, and engine control means 50, and information signals output from the accelerator pedal 16. The driving state of the vehicle C is switched.
Specifically, based on each information signal, a control signal for controlling the operation state is output to the motor control unit 42, the engine control unit 50, and the clutch control unit 52, respectively.
First, an example of control for switching the driving state of the vehicle C from 4WD to 2WD will be described.

  When the driving state of the vehicle C is switched from 4WD to 2WD, for example, based on information signals output from the motor control unit 42, the battery control unit 44, and the accelerator pedal 16, the driving force requested by the driver is used to drive the motor 8. Whether or not output is possible is determined only by the above. At this time, based on the specifications of the motor 8 (generated torque and the like) and the remaining capacity of the battery 32, it is determined whether or not the required driving force can be output only by driving the motor 8.

When it is determined that the required driving force can be output only by driving the motor 8, it is determined whether or not ABS control is performed based on the information signal output by the ABS control means 28.
When it is determined that the requested driving force can be output only by driving the motor 8 and the ABS control is not performed, an information signal including a stop command for stopping the engine 1 is output to the engine control means 50 and the clutch control means 52. To do. Then, an information signal including a torque command value is output to the motor control means 42. The torque command value included in this information signal is calculated so that the driving force of the left and right front wheels 2L, 2R satisfies the required driving force.

On the other hand, when it is determined that the required driving force cannot be output only by driving the motor 8, an information signal including a torque command value is output to the engine control unit 50 and the motor control unit 42. The torque command value included in this information signal is calculated so that the drive torque distribution of the left and right front wheels 2L, 2R and the left and right rear wheels 10L, 10R is an appropriate ratio.
The acceleration comparison means 48 compares the acceleration in the deceleration direction of the vehicle C with the acceleration in the deceleration direction of the vehicle C on the reference road surface based on the information signal output from the acceleration detection means 12 and the reference acceleration stored in advance. .

Hereinafter, the detailed configuration of the acceleration comparison means 48 will be described with reference to FIG.
FIG. 4 is a block diagram showing the configuration of the acceleration comparison means 48.
As shown in FIG. 4, the acceleration comparison unit 48 includes a reference acceleration storage unit 62, an acceleration calculation unit 64, and an acceleration comparison unit 66.
The reference acceleration storage unit 62 includes a map that stores in advance acceleration in the deceleration direction on the reference road surface of the vehicle C according to the behavior of the vehicle C. In the present embodiment, the “reference road surface” is a dry paved road surface. The “behavior of the vehicle C” is the behavior of the vehicle C during braking.

  The acceleration calculation means 64 is based on the information signal output from the acceleration detection means 12 and the map provided in the reference acceleration storage unit 62, and in the deceleration direction predicted to occur on the reference road surface with respect to the vehicle C during actual travel. Calculate acceleration. Then, the calculated information signal including the acceleration in the deceleration direction predicted to occur on the reference road surface with respect to the vehicle C is output to the acceleration comparison unit 66.

Specifically, the map included in the reference acceleration storage unit 62 is adapted to the acceleration in the deceleration direction of the vehicle C included in the information signal output by the acceleration detection unit 12 and is used as a reference for the vehicle C. Acceleration in the deceleration direction that is predicted to occur on the road surface is calculated.
The acceleration comparison unit 66 is based on the map provided in the reference acceleration storage unit 62 and the information signal output by the acceleration calculation means 64, and the acceleration in the deceleration direction of the vehicle C during actual traveling and the reference road surface with respect to the vehicle C. The acceleration in the deceleration direction predicted to occur is compared. Then, an information signal including the comparison result is output to the engine control means 50.

Hereinafter, the description returns to the configuration of the vehicle controller 14.
The engine control means 50 inputs and outputs information signals between the engine 1 and the 4WD controller 46 and controls the driving state of the engine 1 based on these information signals. In addition to this, the driving state of the engine 1 is controlled based on the information signal output by the acceleration comparison means 48.
Further, the engine control means 50 outputs an information signal indicating the driving state of the engine 1 to the 4WD controller 46. Here, the “information signal indicating the driving state of the engine 1” is an information signal indicating a state where the engine 1 is driven and a state where the engine 1 is stopped.

Hereinafter, the control performed by the engine control means 50 will be described.
The engine control means 50 performs control to stop the engine 1 according to the driving force requested by the driver while the motor 8 is being driven.
Thereafter, when the ABS control means 28 is operated while the engine 1 is stopped while the motor 8 is being driven, control is performed to start the stopped engine 1 while the ABS control means 28 is operating.
This control is performed when the acceleration in the deceleration direction detected by the acceleration detection means 12 during the operation of the ABS control means 28 is less than the acceleration in the deceleration direction calculated by the acceleration calculation means 64 during the operation of the ABS control means 28. Limited to.

  Specifically, when the information signal input from the 4WD controller 46 is an information signal including a stop command for stopping the engine 1, a command to stop the drive is given to the engine 1 while the motor 8 is being driven. Output information signal including. As described above, this is a case where the 4WD controller 46 determines that the required driving force can be output only by driving the motor 8 and the ABS control is not performed.

  Thereafter, while the motor 8 is being driven, an information signal including a start command is output to the engine 1 in a state where an information signal including a command to stop driving is output to the engine 1. This is performed only when the information signal input from the ABS control unit 28 is an information signal including a state in which the ABS control unit 28 is operating. Here, the output of the information signal including the start command to the engine 1 is performed while receiving the information signal including the state in which the ABS control means 28 is operating.

In this control, the information signal input from the acceleration comparison means 48 is such that the acceleration in the deceleration direction of the vehicle C during actual traveling is less than the acceleration in the deceleration direction on the reference road surface of the vehicle C during actual traveling. Limited to cases.
Then, only when the above limiting conditions are satisfied, an information signal including a start command is output to the engine 1. The output of the information signal including the start command to the engine 1 is performed while receiving the input of the information signal including the state in which the ABS control means 28 is operating.
The clutch control means 52 inputs / outputs information signals to / from the ABS control means 28 and the 4WD controller 46, and controls the state of the clutch 18 based on these information signals.

Hereinafter, the control performed by the clutch control means 52 will be described.
The clutch control means 52 performs control to release the engine 1 and the left and right front wheels 2L, 2R while the ABS control means 28 is in operation.
Thereafter, when the operating ABS control means 28 is stopped, control for connecting the engine 1 and the left and right front wheels 2L, 2R is performed.
Specifically, a clutch control signal for releasing the clutch 18 is output to the clutch 18 in a state where a clutch control signal for connecting the clutch 18 is output to the clutch 18. This is limited to the case where the information signal input from the ABS control unit 28 is an information signal including a state in which the ABS control unit 28 is operating. Here, the clutch control signal for releasing the clutch 18 is output to the clutch 18 while receiving the information signal including the state in which the ABS control means 28 is operating.

  Thereafter, in a state where a clutch control signal for releasing the clutch 18 is output to the clutch 18, a clutch control signal for connecting the clutch 18 is output to the clutch 18. This is when the information signal input from the ABS control means 28 changes from an information signal including a state in which the ABS control means 28 is operated to an information signal including a state in which the ABS control means 28 is stopped. limit.

Hereinafter, the processing performed by the start control device will be specifically described with reference to FIGS. 1 to 4 and FIG.
FIG. 5 is a flowchart showing processing of the start control device.
The flowchart shown in FIG. 5 starts from a state in which the vehicle C is running in a state where the engine 1 is stopped and the driving state of the vehicle C is switched from 4WD to 2WD (START).

The start control device detects the operating state of the ABS control means 28, for example, every predetermined sampling time when the vehicle C is traveling in a state where the driving state of the vehicle C is 2WD. Thus, it is determined whether the ABS control means 28 is operating or stopped (“ABS is operating?” Shown in FIG. 5) (step S10).
In step S10, the start control device determines whether or not the ABS control unit 28 is operating based on the information signal (see FIG. 3) indicating the operating state of the ABS control unit 28 output from the lock detection unit 56. judge.

If it is determined that the ABS control means 28 is operating (“Yes” shown in the figure), the start control device determines that the friction coefficient of the road surface on which the vehicle C is actually traveling is greater than the friction coefficient of the reference road surface. Is determined to be lower (“low μ?” Shown in FIG. 5) (step S12).
On the other hand, if it is determined in step S10 that the ABS control means 28 is not operating ("No" shown in the figure), the process performed by the start control device returns to the process of step S10 (RETURN).

  In step S12, the start control device determines whether the friction coefficient of the road surface on which the vehicle C is actually traveling is lower than the friction coefficient of the reference road surface based on the information signal output from the acceleration comparison unit 66 to the engine control means 50. It is determined whether or not (see FIG. 4). Specifically, the acceleration in the deceleration direction of the vehicle C during actual traveling (hereinafter referred to as “actual traveling deceleration”) is the acceleration in the deceleration direction that is predicted to occur on the reference road surface with respect to the vehicle C. (Hereinafter referred to as “predicted deceleration”) is determined.

When it is determined that the actual traveling deceleration is less than the predicted deceleration (“Yes” shown in the figure), the start control device determines whether or not the engine 1 is stopped (“shown in FIG. 5”). Engine stop? ") (Step S14).
On the other hand, if it is determined in step S12 that the actual traveling deceleration is not less than the predicted deceleration ("No" shown in the figure), the processing performed by the start control device returns to the processing in step S10 (RETURN).

In step S14, the start control device determines whether or not the engine 1 is stopped based on the information signal output from the engine control means 50 to the 4WD controller 46 (see FIG. 2). Specifically, it is determined whether or not the information signal indicating the driving state of the engine 1 output from the engine control unit 50 to the 4WD controller 46 is an information signal indicating the state in which the engine 1 is stopped. .
If it is determined that the information signal indicating the driving state of the engine 1 is an information signal indicating the state in which the engine 1 is stopped (“Yes” in the figure), the processing of the start control device proceeds to step S16. Transition.

On the other hand, when it is determined in step S14 that the information signal indicating the driving state of the engine 1 is an information signal indicating the driving state of the engine 1 ("No" in the drawing), the process performed by the start control device. Returns to the process of step S10 (RETURN).
In step S16, the start control device starts the engine 1 in the stopped state ("engine start" shown in the figure). Specifically, the engine control unit 50 outputs an information signal including a start command to the engine 1. As described above, this is limited to the case where it is determined in step S10 that the ABS control means 28 is operating, and it is determined in step S12 that the actual traveling deceleration is less than the predicted deceleration. In addition to this, as described above, the determination is made only when it is determined in step S14 that the engine 1 is stopped.
When the engine 1 in the stopped state is started in step S16, the process of the start control device returns to the process of step S10 (RETURN).

(Operation)
Next, the operation of the vehicle including the start control device will be described with reference to FIGS. 1 to 5 and FIG.
FIG. 6 is a time chart showing the operation of the vehicle C provided with the start control device. In FIG. 6, the driving state of the vehicle C is indicated as “vehicle driving state”, and the driving state of the engine 1 is indicated as “engine driving state”. The operation amount of the accelerator pedal 16 is indicated as “accelerator operation amount”, the operation amount of the brake pedal 26 is indicated as “brake operation amount”, and the operating state of the ABS control means 28 is indicated as “ABS operating state”. ing. Further, the driving force requested by the driver is indicated as “required driving force”, the rotational speed of the engine 1 is indicated as “engine rotational speed”, and the driving forces of the left and right front wheels 2L, 2R are indicated as “front wheel driving power”. The driving force of the left and right rear wheels 10L, 10R is indicated as “rear wheel driving force”.

The time chart of FIG. 6 starts from a state where the engine 1 is stopped and the clutch 18 is in a released state when the vehicle C is traveling.
Therefore, at this time (“t0” in the figure), the engine control means 50 outputs an information signal including a command to stop driving to the engine 1 while the motor 8 is being driven, and the engine 1 is driven. Stop. Further, the clutch control means 52 outputs a clutch control signal for releasing the clutch 18 to the clutch 18 so that the driving state of the vehicle C is set to 2WD.

  At time t0, the 4WD controller 46 outputs to the motor control means 42 an information signal including a torque command value calculated so that the driving force of the left and right front wheels 2L, 2R satisfies the required driving force. Then, the motor 8 is driven. That is, the driving wheels of the vehicle C at time t0 are only the left and right rear wheels 10L and 10R among the left and right front wheels 2L and 2R and the left and right rear wheels 10L and 10R.

When the engine 1 is stopped while the motor 8 is being driven and the clutch 18 is in the released state, the driving force requested by the driver decreases and the amount of operation of the accelerator pedal 16 by the driver decreases. The driving force generated is reduced. Thereby, the driving force of the left and right rear wheels 10L, 10R is reduced.
Then, when the driver stops the operation of the accelerator pedal 16 and the driving force requested by the driver becomes “0”, the driving force of the left and right rear wheels 10L, 10R becomes the minimum value.

Note that the brake pedal 26 is not operated and the operation of the ABS control means 28 does not occur between this time (“t1” in the figure) and the time t0. Further, since the engine 1 is stopped, the rotational speed of the engine 1 is the lowest value (0), and the driving state of the vehicle C is 2WD, so that the driving forces of the left and right front wheels 2L, 2R are also the lowest value.
Therefore, at time t1, the vehicle C is traveling by inertia while the accelerator pedal 16 and the brake pedal 26 are not operated by the driver.

When the driving force requested by the driver further decreases from the state where the vehicle C is traveling due to inertia, the driver operates the brake pedal 26.
Note that the accelerator pedal 16 and the brake pedal 26 are not operated between this time (“t2” in the figure) and the time t1, and the operation of the ABS control means 28 is also occurring. Absent. Further, since the engine 1 is stopped, the rotational speed of the engine 1 is the lowest value (0), the driving state of the vehicle C is 2WD, and the accelerator operation amount is also the lowest value, so the left and right front wheels 2L, The driving forces of 2R and left and right rear wheels 10L, 10R are also minimum values.

When the driving force requested by the driver further decreases from the time t2, the amount of operation of the brake pedal 26 increases as the required driving force decreases.
When the lock detection unit 56 detects a tendency to lock each wheel and determines a wheel having a lock tendency in a state where the operation of the brake pedal 26 is continued, the ABS control means 28 is activated. And the ABS control means 28 performs ABS control with respect to the wheel which tends to be locked. This is because when the vehicle C is braked, it is estimated that the road surface on which the vehicle C is traveling has a lower friction coefficient (low μ road surface) than the reference road surface which is a dry road surface (shown as “low μ estimation” in the figure). Range).

Further, the lock detection unit 56 that has detected a wheel having a tendency to lock outputs an information signal including the detection result to the 4WD controller 46, the engine control unit 50, and the clutch control unit 52.
When the ABS control means 28 is activated, at this time ("t3" shown in the figure), the engine control means 50 that has received the input of the information signal output from the lock detection unit 56 is in operation of the ABS control means 28. An information signal including a start command is output to the engine 1.

Since the engine 1 is stopped between the time point t3 and the time point t2, the rotational speed of the engine 1 is the lowest value (0). Further, since the driving state of the vehicle C is 2WD and the accelerator operation amount is also the lowest value, the driving forces of the left and right front wheels 2L, 2R and the left and right rear wheels 10L, 10R are also the lowest value.
While the ABS control means 28 is in operation, the engine 1 that has received an input of an information signal including a start command from the engine control means 50 starts from a stopped state. Here, a time lag occurs between the time t3 when the engine control means 50 outputs the information signal including the start command to the engine 1 and the time when the stopped engine 1 is actually started.

When the stopped engine 1 is actually started, the engine 1 is driven from this time ("t4" shown in the figure), and the engine 1 rotates from the lowest value (0) toward the idling engine speed. To increase.
In addition, since the engine 1 has stopped between the time t4 and the time t3, the rotation speed of the engine 1 is the lowest value (0). Further, since the driving state of the vehicle C is 2WD and the accelerator operation amount is the lowest value, the driving forces of the left and right front wheels 2L, 2R and the left and right rear wheels 10L, 10R are also the lowest value.

When the driving force requested by the driver increases while the engine 1 in the stopped state is started and the engine 1 is driven while the ABS control means 28 is operating, the driver decreases the amount of operation of the brake pedal 26. Let This is the case, for example, when the road surface on which the vehicle C is traveling becomes a road surface with a higher coefficient of friction than the low μ road surface, and the tendency of the wheels to lock is reduced.
When the driver decreases the amount of operation of the brake pedal 26 while the ABS control means 28 is operating, the ABS control means 28 that is operating stops ABS control at this time ("t5" shown in the figure).

The lock detection unit 56 that has detected a decrease in the lock tendency outputs an information signal including the detection result to the 4WD controller 46, the engine control unit 50, and the clutch control unit 52. This information signal includes information for stopping the ABS control.
The engine 1 is started between the time t5 and the time t4. However, since the accelerator operation amount is the minimum value, the rotation speed of the engine 1 is the idling rotation speed. Further, since the driving state of the vehicle C is 2WD and the accelerator operation amount is also the lowest value, the driving forces of the left and right front wheels 2L, 2R and the left and right rear wheels 10L, 10R are also the lowest value.

At time t5 when the operating ABS control means 28 stops the ABS control, the clutch control means 52 outputs a clutch control signal for setting the clutch 18 to the released clutch 18.
When a clutch control signal for connecting the clutch 18 is output to the clutch 18 in the released state, the clutch 18 in the released state is connected and the driving state of the vehicle C is switched from 2WD to 4WD.

  Here, the engine 1 is started during the operation of the ABS control means 28 before the clutch 18 in the released state is in the connected state, and the number of revolutions of the engine 1 is in the connected state in the released clutch 18. Before, the idling speed has increased. For this reason, when the clutch 18 in the released state is set to the connected state, the driving state of the vehicle C is switched from 2WD to 4WD in a short time. Specifically, the time that elapses from when the clutch control means 52 outputs a clutch control signal for engaging the clutch 18 until the driving state of the vehicle C switches from 2WD to 4WD is determined by the clutch 18 The time is as short as the time of the half-clutch state.

Therefore, from the state where the engine 1 is stopped and the supply of driving force to the left and right front wheels 2L and 2R driven by the engine is stopped, the engine 1 is started and the driving force is supplied to the left and right front wheels 2L and 2R. Such time can be shortened.
When the disengaged clutch 18 is in the connected state and the driving state of the vehicle C is switched from 2WD to 4WD and the driving force requested by the driver further increases from the time t5, the driver And the operation of the brake pedal 26 is stopped. At this time (“t6” in the figure), the driver who has stopped operating the brake pedal 26 starts operating the accelerator pedal 16.

The engine 1 is started between the time point t6 and the time point t5. However, since the accelerator operation amount is the lowest value, the rotational speed of the engine 1 is the idling rotational speed. Further, since the driving state of the vehicle C is 2WD and the accelerator operation amount is the lowest value, the driving forces of the left and right front wheels 2L, 2R and the left and right rear wheels 10L, 10R are also the lowest value.
Here, as described above, the driving state of the vehicle C is switched from 2WD to 4WD. For this reason, the amount of operation of the accelerator pedal 16 is increased according to the driving force required by the driver, and the driving force of the left and right front wheels 2L, 2R increases as the rotational speed of the engine 1 increases. Further, when the operation amount of the accelerator pedal 16 is increased, the driving force of the motor 8 is also increased.

Therefore, after the time t6, when the driving force requested by the driver increases and the amount of operation of the accelerator pedal 16 increases, the driving forces of the left and right front wheels 2L, 2R and the left and right rear wheels 10L, 10R also increase.
Note that, as described above, the engine start control method (start control method) implemented by the operation of the start control device of the present embodiment is performed while the motor 8 is being driven in accordance with the driving force requested by the driver. Stop. In addition to this, when the ABS control means 28 is operated while the engine 1 is stopped while the motor 8 is being driven, the stopped engine 1 is started while the ABS control means 28 is operating.

(Effects of the first embodiment)
(1) In the start control device of the present embodiment, the engine control means stops the engine during driving of the motor according to the driving force requested by the driver. Further, when the ABS control means is operated while the engine is stopped while the motor is being driven, the stopped engine is started while the ABS control means is operating.
For this reason, the driving state of the vehicle is changed from a state in which the engine is stopped and the supply of driving force to the left and right front wheels driven by the engine is stopped to a state in which the driving force is supplied to the left and right front wheels. It is possible to shorten the time required for the process.
As a result, the time required for starting the engine and switching the driving state from 2WD to 4WD for the vehicle in which the engine is stopped and the driving state is switched from 4WD to 2WD as in the present embodiment can be shortened. It becomes possible.

  As a result, even when the driving force requested by the driver is large after the braking state is finished, it becomes possible to transmit the driving force of the engine to the wheels driven by the engine in a short time, thereby stabilizing the steering of the vehicle. It becomes possible to improve the property. In particular, the ABS control is often performed in a state where the vehicle is traveling on a low μ road surface. Therefore, in a situation where a large driving force for the low μ road surface is required after the ABS control is finished, the driving state is set to 2WD. It is preferable to reduce the time required for switching from 4 to 4WD.

(2) In the start control device of the present embodiment, the engine control means starts the engine stopped while the motor is driven while the ABS control means is operating.
For this reason, the operation of the ABS control means makes it possible to start the engine while the vehicle is vibrating.
As a result, the vibration generated in the vehicle by starting the engine can be mixed with the vibration generated in the vehicle by the operation of the ABS control means, and the vibration transmitted to the driver by starting the engine can be reduced. Is possible.

(3) In the start control device of the present embodiment, the engine control means starts the stopped engine while the ABS control means is operating. This is performed only when the acceleration in the deceleration direction detected by the acceleration detection means during operation of the ABS control means is less than the acceleration in the deceleration direction calculated by the acceleration calculation means during operation of the ABS control means. .
For this reason, in a situation where the road surface on which the vehicle is actually traveling has a lower coefficient of friction than the reference road surface that is a dry road surface and is likely to cause wheel lock and vehicle slip, a short time after the ABS control ends. A large driving force can be output.
As a result, even when the driving force requested by the driver is large after the braking state is finished, it becomes possible to suppress the occurrence of wheel lock and vehicle slip, and improve the steering stability of the vehicle. It becomes possible.

(4) In the start control device of the present embodiment, the clutch control means releases the engine and the left and right front wheels while the ABS control means is operating, and when the operating ABS control means stops, the engine and the left and right front wheels are disconnected. Connecting.
For this reason, during the operation of the ABS control means, the driving force transmission path between the engine and the left and right front wheels is cut off, and the driving force of the engine started during the operation of the ABS control means is transmitted to the left and right front wheels. This can be prevented.
As a result, it is possible to prevent the stability of the ABS control from being lowered, and it is possible to apply a large driving force to the vehicle immediately after the ABS control means is stopped. Stability can be improved.

(5) In the start control method of the present embodiment, the engine is stopped while the motor is driven according to the driving force requested by the driver, and the ABS control means is operated when the engine is stopped. The engine is started during operation of the ABS control means.
For this reason, it is possible to reduce the time required to start the engine and switch the drive state from 2WD to 4WD for a vehicle in which the engine is stopped and the drive state is switched from 4WD to 2WD.
As a result, even when the driving force requested by the driver is large after the braking state is finished, it becomes possible to transmit the driving force of the engine to the wheels driven by the engine in a short time, thereby stabilizing the steering of the vehicle. It becomes possible to improve the property.
(Application examples)
(1) In the start control device of the present embodiment, the engine drive wheels driven by the engine 1 are the left and right front wheels 2L, 2R. However, the present invention is not limited to this, and the engine drive wheels driven by the engine 1 are The rear wheels 10L and 10R may be used. In this case, when the engine driving wheels driven by the engine 1 are the left and right rear wheels 10L and 10R, the wheels driven by the motor 8 are the left and right front wheels 2L and 2R. That is, the engine driving wheel driven by the engine 1 may be one of the front wheel 2 and the rear wheel 10. The wheel driven by the motor 8 may be the other of the front wheel 2 and the rear wheel 10.

(2) In the start control device of the present embodiment, the configuration of the acceleration detecting means 12 is configured to include a longitudinal acceleration / deceleration sensor that detects acceleration and deceleration in the vehicle longitudinal direction of the vehicle C, but is not limited thereto. Not what you want. That is, the configuration of the acceleration detecting means 12 may be configured to detect the acceleration and deceleration of the vehicle C in the vehicle longitudinal direction by the front wheel speed sensors 22L and 22R and the rear wheel speed sensors 38L and 38R.
(3) In the start control device of the present embodiment, the engine 1 is stopped in a state where the driving state of the vehicle C is 2WD and the vehicle C is traveling only by the driving force of the motor 8, but the present invention is limited to this. Not what you want. That is, the engine 1 may be stopped in a state where regenerative braking by the motor 8 is performed.

(4) In the start control device of the present embodiment, when the operating ABS control means 28 stops the ABS control, the released clutch 18 is brought into the connected state. However, the present invention is not limited to this. In other words, for example, the operating ABS control unit 28 may stop the ABS control, and the released clutch 18 may be in a connected state in a state where a request for starting a known VDC control (running stability control) has occurred.

(Second embodiment)
Next, a second embodiment of the present invention (hereinafter referred to as “the present embodiment”) will be described with reference to the drawings.
(Constitution)
First, the configuration of the start control device of the present embodiment will be described with reference to FIGS.
The configuration of the start control device of the present embodiment is the same as that of the first embodiment described above except for the configuration of the vehicle controller 14. For this reason, the description regarding another structure is abbreviate | omitted.
FIG. 7 is a block diagram showing the configuration of the vehicle controller 14.
As shown in FIG. 7, the vehicle controller 14 includes an ABS controller 28, a motor controller 42, a battery controller 44, and a 4WD controller 46. In addition to this, the vehicle controller 14 includes acceleration comparison means 48, braking force determination means 68, engine control means 50, and clutch control means 52.

The configuration of the vehicle controller 14 is the same as that of the above-described first embodiment except for the configurations of the braking force determination unit 68 and the clutch control unit 52, and therefore the description other than the braking force determination unit 68 and the clutch control unit 52 will be given. Is omitted.
Based on the information signal output from the brake pedal 26 and a predetermined braking force stored in advance, the braking force determination means 68 determines whether the required braking force requested by the driver is equal to or less than the predetermined braking force. . Then, an information signal including the determination result is output to the clutch control means 52.

Hereinafter, the detailed configuration of the braking force determination unit 68 will be described with reference to FIG.
FIG. 8 is a block diagram showing a configuration of the braking force determination means 68.
As shown in FIG. 8, the braking force determination unit 68 includes a required braking force detection unit 70, a predetermined braking force storage unit 72, and a braking force comparison unit 74.
The required braking force detection means 70 calculates the required braking force based on the amount of operation of the brake pedal 26 by the driver, similarly to the required braking force calculation unit 58 provided in the ABS control means 28. Then, an information signal including the calculation result is output to the braking force comparison unit 74.

The predetermined braking force storage unit 72 stores a predetermined braking force set in advance. In the present embodiment, the “predetermined braking force” is the braking force when the operation amount of the brake pedal 26 is “0”, that is, the brake pedal 26 is not depressed.
The predetermined braking force described above is not limited to the braking force when the brake pedal 26 is not depressed. For example, the amount of operation of the brake pedal 26 is 1 when the brake pedal 26 is fully depressed. It may be a braking force when the operation amount is about / 10. That is, a predetermined braking force may be set according to a desired braking force.

The braking force comparison unit 74 is based on the information signal output from the requested braking force detection unit 70 and the predetermined braking force stored in the predetermined braking force storage unit 72, and the requested braking force detected by the requested braking force detection unit 70. And a predetermined braking force. Then, an information signal including the comparison result is output to the clutch control means 52.
As described above, the braking force determination unit 68 determines whether or not the braking force detected by the required braking force detection unit 70 is equal to or less than a predetermined braking force.
The clutch control means 52 inputs and outputs information signals to and from the ABS control means 28, the 4WD controller 46 and the braking force determination means 68, and based on these information signals, the state of the clutch 18 is changed. Control.

Hereinafter, the control performed by the clutch control means 52 will be described.
The clutch control means 52 performs control to release the engine 1 and the left and right front wheels 2L, 2R while the ABS control means 28 is in operation.
Thereafter, when the operating ABS control means 28 is stopped and the braking force determination means 68 determines that the braking force detected by the required braking force detection means 70 is less than or equal to a predetermined braking force, the engine 1 and the left and right front wheels 2L 2R is controlled.

  Specifically, a clutch control signal for releasing the clutch 18 is output to the clutch 18 in a state where a clutch control signal for connecting the clutch 18 is output to the clutch 18. This is limited to the case where the information signal input from the ABS control unit 28 is an information signal including a state in which the ABS control unit 28 is operating. Here, the clutch control signal for releasing the clutch 18 is output to the clutch 18 while receiving the information signal including the state in which the ABS control means 28 is operating.

  Thereafter, in a state where a clutch control signal for releasing the clutch 18 is output to the clutch 18, a clutch control signal for connecting the clutch 18 is output to the clutch 18. This is when the information signal input from the ABS control means 28 changes from an information signal including a state in which the ABS control means 28 is operated to an information signal including a state in which the ABS control means 28 is stopped. limit. In addition to this, the information signal input from the braking force determination unit 68 is limited to a case where the required braking force detected by the required braking force detection unit 70 includes a comparison result that is equal to or less than a predetermined braking force.

Hereinafter, the processing performed by the start control device will be specifically described with reference to FIGS. 1 to 8 and FIG.
FIG. 9 is a flowchart showing processing of the start control device.
The flowchart shown in FIG. 9 starts from a state in which the vehicle C is running in a state where the engine 1 is stopped and the driving state of the vehicle C is switched from 4WD to 2WD (START).
The start control device detects the operating state of the ABS control means 28, for example, every predetermined sampling time when the vehicle C is traveling in a state where the driving state of the vehicle C is 2WD. Thereby, it is determined whether or not the ABS control means 28 is operating (“ABS operating?” Shown in FIG. 9) (step S20).

In step S20, the start control device determines whether or not the ABS control means 28 is operating based on the information signal (see FIG. 3) indicating the operating state of the ABS control means 28 output from the lock detection unit 56. judge.
If it is determined that the ABS control means 28 is operating (“Yes” shown in the figure), the start control device determines that the friction coefficient of the road surface on which the vehicle C is actually traveling is greater than the friction coefficient of the reference road surface. Is determined to be lower (“low μ?” Shown in FIG. 9) (step S22).
On the other hand, if it is determined in step S20 that the ABS control means 28 is not operating ("No" in the figure), the start control device determines whether or not the braking force requested by the driver is equal to or less than a predetermined braking force. Is determined (“required braking force is small?” Shown in FIG. 9) (step S24).

In step S22, the start control device determines whether the friction coefficient of the road surface on which the vehicle C is actually traveling is lower than the friction coefficient of the reference road surface based on the information signal output from the acceleration comparison unit 66 to the engine control means 50. It is determined whether or not (see FIG. 4). Specifically, it is determined whether or not the actual traveling deceleration is less than the predicted deceleration.
When it is determined that the actual traveling deceleration is less than the predicted deceleration (“Yes” shown in the figure), the start control device determines whether or not the engine 1 is stopped (“shown in FIG. 9”). Engine stop? ") (Step S26).

On the other hand, if it is determined in step S22 that the actual travel deceleration is not less than the predicted deceleration ("No" shown in the figure), the process performed by the start control device returns to the process of step S20 (RETURN).
In step S24, the start control device determines whether or not the required braking force requested by the driver is equal to or less than a predetermined braking force based on the information signal output from the braking force comparison unit 74 to the clutch control means 52. (See FIG. 8). Specifically, it is determined whether the braking force generated by the amount of operation of the brake pedal 26 by the driver is equal to or less than a predetermined braking force set in advance.

When it is determined that the braking force generated by the amount of operation of the brake pedal 26 by the driver is equal to or less than a predetermined braking force set in advance ("Yes" shown in the figure), the process of the start control device is performed in step S26. Migrate to
On the other hand, when it is determined in step S24 that the braking force generated by the amount of operation of the brake pedal 26 by the driver exceeds a predetermined braking force set in advance ("No" shown in the drawing), the process performed by the start control device. Returns to the processing of step S20 (RETURN).

  In step S26, the start control device determines whether or not the engine 1 is stopped based on the information signal output from the engine control means 50 to the 4WD controller 46 (see FIG. 2). Specifically, it is determined whether or not the information signal indicating the driving state of the engine 1 output from the engine control unit 50 to the 4WD controller 46 is an information signal indicating the state in which the engine 1 is stopped. .

If it is determined that the information signal indicating the driving state of the engine 1 is an information signal indicating the state in which the engine 1 is stopped (“Yes” in the figure), the processing of the start control device proceeds to step S28. Transition.
On the other hand, if it is determined in step S26 that the information signal indicating the driving state of the engine 1 is an information signal indicating the driving state of the engine 1 ("No" in the drawing), the process performed by the start control device. Returns to the processing of step S20 (RETURN).

In step S28, the start control device starts the engine 1 in the stopped state ("engine start" shown in the figure). Specifically, the engine control unit 50 outputs an information signal including a start command to the engine 1. As described above, this is limited to the case where it is determined in step S20 that the ABS control means 28 is operating, and in step S22, it is determined that the actual travel deceleration is less than the predicted deceleration. In addition, as described above, this is limited to the case where it is determined in step S24 whether or not the braking force generated by the amount of operation of the brake pedal 26 by the driver is equal to or less than a predetermined braking force set in advance. Furthermore, it is limited to the case where it is determined in step S26 that the engine 1 is stopped.
When the engine 1 in the stopped state is started in step S28, the process of the start control device returns to the process of step S20 (RETURN).
Other configurations are the same as those of the first embodiment described above.

(Operation)
Next, with reference to FIGS. 1 to 5 and FIGS. 7 to 9, the operation of the vehicle including the start control device will be described with reference to FIG.
FIG. 10 is a time chart showing the operation of the vehicle C provided with the start control device. In FIG. 10, the driving state of the vehicle C, the amount of operation of the accelerator pedal 16, the driving force requested by the driver, and the like are indicated by the same description as in FIG.
The time chart of FIG. 10 starts from a state where the engine 1 is stopped and the clutch 18 is in a released state when the vehicle C is traveling.

In addition, since the operation | movement from the time of t0 shown in FIG. 10 to the time of t5 is the same as that of 1st Embodiment mentioned above, detailed description is abbreviate | omitted.
At time t0, the engine control means 50 outputs an information signal including a command to stop driving to the engine 1 while the motor 8 is driving, and stops driving of the engine 1. Further, the clutch control means 52 outputs a clutch control signal for releasing the clutch 18 to the clutch 18 so that the driving state of the vehicle C is set to 2WD.

When the driving force requested by the driver further decreases from the state in which the vehicle C is traveling due to inertia, the driver is operating the brake pedal 26 and the lock detection unit 56 is locked. When the wheel located at is determined, the ABS control means 28 is activated.
At time t3 when the ABS control means 28 is operated, when the engine control means 50 outputs an information signal including a start command to the engine 1 while the ABS control means 28 is operating, the engine that has received the input of this information signal. 1 starts from a stop state.

When the driving force requested by the driver increases while the engine 1 in the stopped state is started and the engine 1 is driven while the ABS control means 28 is operating, the driver decreases the amount of operation of the brake pedal 26. The operating ABS control means 28 stops the ABS control.
If the driving force requested by the driver further increases from the time t5 in a state where the ABS control means 28 in operation has stopped the ABS control, the driver decreases the operation amount of the brake pedal 26.

When the driver reduces the amount of operation of the brake pedal 26 and the braking force requested by the driver is equal to or less than the predetermined braking force, at this point (“t6” in the figure), the clutch control means 52 is in the released state. A clutch control signal for connecting the clutch 18 is output to the clutch 18.
When a clutch control signal for connecting the clutch 18 is output to the clutch 18 in the released state, the clutch 18 in the released state is connected and the driving state of the vehicle C is switched from 2WD to 4WD.

When the driving force requested by the driver further increases from the time t6, the driver who has decreased the operation amount of the brake pedal 26 at the time t6 stops the operation of the brake pedal 26 and starts the operation of the accelerator pedal 16. To do.
Here, as described above, the driving state of the vehicle C is switched from 2WD to 4WD. For this reason, the amount of operation of the accelerator pedal 16 is increased according to the driving force required by the driver, and the driving force of the left and right front wheels 2L, 2R increases as the rotational speed of the engine 1 increases. Further, when the operation amount of the accelerator pedal 16 is increased, the driving force of the motor 8 is also increased.
Therefore, after the time when the operation of the accelerator pedal 16 is started ("t7" shown in the figure), the driving force requested by the driver increases, and when the operation amount of the accelerator pedal 16 increases, the left and right front wheels 2L, 2R and The driving force of the left and right rear wheels 10L, 10R also increases.

(Effect of the second embodiment)
(1) In the start control device of the present embodiment, the clutch control means stops the operating ABS control means, and the braking force detected by the required braking force detection means by the braking force determination means is equal to or less than a predetermined braking force. If determined to be, the engine and the left and right front wheels are connected.
For this reason, it is possible to maintain the state in which the engine and the left and right front wheels are released when the braking force requested by the driver exceeds a predetermined braking force with the ABS control means in operation stopped. Become.
As a result, it is possible to prevent a reduction in braking force after the ABS control means has stopped, and to apply a large driving force to the vehicle immediately after the end of the braking state. It is possible to improve the steering stability of the vehicle.

(Third embodiment)
Next, a third embodiment of the present invention (hereinafter referred to as “the present embodiment”) will be described with reference to the drawings.
(Constitution)
First, the configuration of the start control device of the present embodiment will be described with reference to FIGS.
The configuration of the start control device of the present embodiment is the same as that of the first embodiment described above except for the configuration of the vehicle controller 14. For this reason, the description regarding another structure is abbreviate | omitted.

FIG. 11 is a block diagram showing the configuration of the vehicle controller 14.
As shown in FIG. 11, the vehicle controller 14 includes an ABS controller 28, a motor controller 42, a battery controller 44, and a 4WD controller 46. In addition, the vehicle controller 14 includes an acceleration comparison unit 48, a driving force determination unit 76, an engine control unit 50, and a clutch control unit 52.

The configuration of the vehicle controller 14 is the same as that of the first embodiment described above except for the configurations of the driving force determination unit 76 and the clutch control unit 52, and therefore description other than the driving force determination unit 76 and the clutch control unit 52 is provided. Is omitted.
Based on the information signal output from the accelerator pedal 16 and a predetermined driving force stored in advance, the driving force determination means 76 determines whether the required driving force requested by the driver is equal to or greater than the predetermined driving force. . Then, an information signal including the determination result is output to the clutch control means 52.

Hereinafter, the detailed configuration of the driving force determination unit 76 will be described with reference to FIG.
FIG. 12 is a block diagram illustrating a configuration of the driving force determination unit 76.
As shown in FIG. 12, the driving force determination unit 76 includes a required driving force detection unit 78, a predetermined driving force storage unit 80, and a driving force comparison unit 82.
The required driving force detection means 78 calculates the required driving force based on the amount of operation of the accelerator pedal 16 by the driver. Then, an information signal including the calculation result is output to the driving force comparison unit 82.

The predetermined driving force storage unit 80 stores a predetermined driving force set in advance. In the present embodiment, the “predetermined driving force” is the driving force when the operation amount of the accelerator pedal 16 is “over 0”, that is, the accelerator pedal 16 is depressed.
The predetermined driving force described above is not limited to the driving force in a state where the accelerator pedal 16 is depressed. For example, the operation amount of the accelerator pedal 16 is such that the speed of the vehicle C exceeds 20 km / h. It is good also as a driving force in case it is the operation amount of. That is, a predetermined driving force may be set according to a desired vehicle speed.

The driving force comparison unit 82 is based on the information signal output from the required driving force detection unit 78 and the predetermined driving force stored in the predetermined driving force storage unit 80, and the required driving force detected by the required driving force detection unit 78. And a predetermined driving force. Then, an information signal including the comparison result is output to the clutch control means 52.
As described above, the driving force determination unit 76 determines whether or not the driving force detected by the required driving force detection unit 78 is equal to or greater than a predetermined driving force.
The clutch control means 52 inputs / outputs information signals to / from the ABS control means 28, the 4WD controller 46, and the driving force determination means 76, and determines the state of the clutch 18 based on these information signals. Control.

Hereinafter, the control performed by the clutch control means 52 will be described.
The clutch control means 52 performs control to release the engine 1 and the left and right front wheels 2L, 2R while the ABS control means 28 is in operation.
Thereafter, when the operating ABS control means 28 is stopped and the driving force determination means 76 determines that the driving force detected by the required driving force detection means 78 is equal to or greater than the predetermined driving force, the engine 1 and the left and right front wheels 2L. 2R is controlled.

  Specifically, a clutch control signal for releasing the clutch 18 is output to the clutch 18 while a clutch control signal for connecting the clutch 18 is output to the clutch 18. This is limited to the case where the information signal input from the ABS control unit 28 is an information signal including a state in which the ABS control unit 28 is operating. Here, the clutch control signal for releasing the clutch 18 is output to the clutch 18 while receiving the information signal including the state in which the ABS control means 28 is operating.

  Thereafter, in a state where a clutch control signal for releasing the clutch 18 is output to the clutch 18, a clutch control signal for connecting the clutch 18 is output to the clutch 18. This is when the information signal input from the ABS control means 28 changes from an information signal including a state in which the ABS control means 28 is operated to an information signal including a state in which the ABS control means 28 is stopped. limit. In addition to this, the information signal input from the driving force determination unit 76 is limited to a case where the required driving force detected by the required driving force detection unit 78 includes a comparison result that is equal to or greater than a predetermined driving force.

Hereinafter, the process performed by the start control device will be specifically described with reference to FIGS. 1 to 12 and FIG.
FIG. 13 is a flowchart showing processing of the start control device.
The flowchart shown in FIG. 13 starts from a state in which the vehicle C is running in a state where the engine 1 is stopped and the driving state of the vehicle C is switched from 4WD to 2WD (START).

The start control device detects the operating state of the ABS control means 28, for example, every predetermined sampling time when the vehicle C is traveling in a state where the driving state of the vehicle C is 2WD. Thereby, it is determined whether the ABS control means 28 is operating or stopped ("ABS operating?" Shown in FIG. 13) (step S30).
In step S30, the start control device determines whether the ABS control unit 28 is operating based on an information signal (see FIG. 3) indicating the operating state of the ABS control unit 28 output from the lock detection unit 56. judge.

If it is determined that the ABS control means 28 is operating (“Yes” shown in the figure), the start control device determines that the friction coefficient of the road surface on which the vehicle C is actually traveling is greater than the friction coefficient of the reference road surface. Is determined to be lower (“low μ?” Shown in FIG. 13) (step S32).
On the other hand, if it is determined in step S30 that the ABS control means 28 is not operating ("No" shown in the figure), the start control device determines whether or not the driving force requested by the driver is greater than or equal to a predetermined driving force. Is determined ("required driving force is large" shown in FIG. 13) (step S34).

In step S32, the start control device determines whether the friction coefficient of the road surface on which the vehicle C is actually traveling is lower than the friction coefficient of the reference road surface based on the information signal output from the acceleration comparison unit 66 to the engine control means 50. It is determined whether or not (see FIG. 4). Specifically, it is determined whether or not the actual traveling deceleration is less than the predicted deceleration.
When it is determined that the actual traveling deceleration is less than the predicted deceleration (“Yes” shown in the figure), the start control device determines whether or not the engine 1 is stopped (“shown in FIG. 13”). Engine stop? ") (Step S36).

On the other hand, if it is determined in step S32 that the actual traveling deceleration is not less than the predicted deceleration ("No" shown in the figure), the processing performed by the start control device returns to the processing in step S30 (RETURN).
In step S34, the start control device determines whether the required drive force requested by the driver is equal to or greater than a predetermined drive force based on the information signal output from the drive force comparison unit 82 to the clutch control means 52. It is determined whether or not (see FIG. 12). Specifically, it is determined whether or not the driving force generated by the amount of operation of the accelerator pedal 16 by the driver is greater than or equal to a predetermined driving force set in advance.

When it is determined that the driving force generated by the amount of operation of the accelerator pedal 16 by the driver is greater than or equal to a predetermined driving force set in advance (“Yes” shown in the drawing), the processing of the start control device is performed in step S36. Migrate to
On the other hand, when it is determined in step S34 that the driving force generated by the amount of operation of the accelerator pedal 16 by the driver is greater than or equal to a predetermined driving force set in advance ("No" shown in the drawing), the start control device performs. The process returns (RETURN) to the process of step S30.

  In step S36, the start control device determines whether or not the engine 1 is stopped based on the information signal output from the engine control means 50 to the 4WD controller 46 (see FIG. 2). Specifically, it is determined whether or not the information signal indicating the driving state of the engine 1 output from the engine control unit 50 to the 4WD controller 46 is an information signal indicating the state in which the engine 1 is stopped. .

If it is determined that the information signal indicating the driving state of the engine 1 is an information signal indicating the state in which the engine 1 is stopped (“Yes” in the drawing), the processing of the start control device proceeds to step S38. Transition.
On the other hand, if it is determined in step S36 that the information signal indicating the driving state of the engine 1 is an information signal indicating the driving state of the engine 1 ("No" in the drawing), the process performed by the start control device. Returns to the processing of step S30 (RETURN).

In step S38, the start control device starts the engine 1 in the stopped state ("engine start" shown in the figure). Specifically, the engine control unit 50 outputs an information signal including a start command to the engine 1. As described above, this is limited to the case where it is determined in step S30 that the ABS control means 28 is operating, and in step S32, it is determined that the actual traveling deceleration is less than the predicted deceleration. In addition, as described above, this is limited to the case where it is determined in step S34 that the driving force generated by the amount of operation of the accelerator pedal 16 by the driver is greater than or equal to a predetermined driving force set in advance. Furthermore, it is limited to the case where it is determined in step S36 that the engine 1 is stopped.
When the engine 1 in the stopped state is started in step S38, the process of the start control device returns to the process of step S30 (RETURN).
Other configurations are the same as those of the first embodiment described above.

(Operation)
Next, the operation of the vehicle provided with the start control device will be described with reference to FIGS. 1 to 5 and FIGS. 11 to 13 and FIG.
FIG. 14 is a time chart showing the operation of the vehicle C provided with the start control device. In FIG. 14, the driving state of the vehicle C, the operation amount of the accelerator pedal 16, the driving force requested by the driver, and the like are indicated by the same description as in FIG. 6.
The time chart of FIG. 14 starts from a state where the engine 1 is stopped and the clutch 18 is in a released state when the vehicle C is traveling.

Note that the operation from the time point t0 to the time point t5 shown in FIG. 14 is the same as that in the first embodiment described above, and thus detailed description thereof is omitted.
At time t0, the engine control means 50 outputs an information signal including a command to stop driving to the engine 1 while the motor 8 is driving, and stops driving of the engine 1. Further, the clutch control means 52 outputs a clutch control signal for releasing the clutch 18 to the clutch 18 so that the driving state of the vehicle C is set to 2WD.

When the driving force requested by the driver further decreases from the state in which the vehicle C is traveling due to inertia, the driver is operating the brake pedal 26 and the lock detection unit 56 is locked. When the wheel located at is determined, the ABS control means 28 is activated.
At time t3 when the ABS control means 28 is operated, when the engine control means 50 outputs an information signal including a start command to the engine 1 while the ABS control means 28 is operating, the engine that has received the input of this information signal. 1 starts from a stop state.

When the driving force requested by the driver increases while the engine 1 in the stopped state is started and the engine 1 is driven while the ABS control means 28 is operating, the driver decreases the amount of operation of the brake pedal 26. The operating ABS control means 28 stops the ABS control.
When the driving force requested by the driver further increases from the time t5 in a state where the ABS control means 28 that is operating is stopped, the driver decreases the operation amount of the brake pedal 26 and Stop the operation.

When the driving force requested by the driver further increases from the time when the driver stops operating the brake pedal 26 ("t6" in the figure), the driver who stops operating the brake pedal 26 The operation of the pedal 16 is started.
When the driver increases the amount of operation of the accelerator pedal 16 and the driving force requested by the driver becomes equal to or greater than the predetermined driving force, at this point (“t7” in the figure), the clutch control means 52 is in the released state. A clutch control signal for connecting the clutch 18 is output to the clutch 18.

When a clutch control signal for connecting the clutch 18 is output to the clutch 18 in the released state, the clutch 18 in the released state is connected and the driving state of the vehicle C is switched from 2WD to 4WD.
Here, as described above, the driving state of the vehicle C is switched from 2WD to 4WD. For this reason, the amount of operation of the accelerator pedal 16 is increased according to the driving force required by the driver, and the driving force of the left and right front wheels 2L, 2R increases as the rotational speed of the engine 1 increases. Further, when the operation amount of the accelerator pedal 16 is increased, the driving force of the motor 8 is also increased.
Therefore, after the time t7, when the driving force requested by the driver increases and the amount of operation of the accelerator pedal 16 increases, the driving forces of the left and right front wheels 2L, 2R and the left and right rear wheels 10L, 10R also increase.

(Effect of the third embodiment)
(1) In the start control device of the present embodiment, the clutch control means stops the operating ABS control means, and the driving force detected by the required driving force detection means by the driving force determination means exceeds a predetermined driving force. If determined to be, the engine and the left and right front wheels are connected.
For this reason, when the operating ABS control means is stopped and the driving force requested by the driver is less than the predetermined driving force, the engine and the left and right front wheels can be kept released. .

As a result, in a state where the driving force requested by the driver is small, such as when the braking state continues after the ABS control unit stops, the driving force of the engine started during the operation of the ABS control unit is It is possible to prevent transmission to the front wheels. Further, when the driving force requested by the driver increases, such as immediately after the ABS control means is stopped and the braking state is finished, it becomes possible to apply a large driving force to the vehicle.
Thereby, it becomes possible to improve the steering stability of the vehicle.

(Application examples)
(1) In the start control device of the present embodiment, the clutch control means 52 connects the engine 1 and the left and right front wheels 2L, 2R. This is limited to the case where the operating ABS control means 28 is stopped and the driving force determination means 76 determines that the driving force detected by the required driving force detection means 78 is equal to or greater than the predetermined driving force. Yes.
However, the condition for the clutch control means 52 to connect the engine 1 and the left and right front wheels 2L, 2R is not limited to this.

  That is, for example, the configuration of the vehicle controller 14 includes a braking force determination unit 68 and a driving force determination unit 76. And the control which connects the engine 1 and the left and right front wheels 2L and 2R performed by the clutch control means 52 is stopped by the operating ABS control means 28, and one of the following two conditions is set as the running condition or You may set by a driver | operator's selection. In addition, selection of the control which connects the engine 1 and right-and-left front wheels 2L and 2R is performed by the switch type switch etc. which were arrange | positioned in the driver seat vicinity, for example.

The first condition is a case where the braking force determination unit 68 determines that the braking force detected by the required braking force detection unit 70 is equal to or less than a predetermined braking force.
On the other hand, the second condition is a case where the driving force determination unit 76 determines that the driving force detected by the required driving force detection unit 78 is equal to or greater than a predetermined driving force.
By adopting such a configuration, for example, in a driving situation where a low μ road surface such as a snowy road continues, even when the required driving force is small, by connecting the engine 1 and the left and right front wheels 2L, 2R, It is possible to perform control with an emphasis on steering stability.
On the other hand, for example, in a driving situation where a good road surface such as a dry road continues, when the required driving force is small, the engine 1 and the left and right front wheels 2L, 2R are not connected, and control with an emphasis on fuel consumption can be performed. Become.

1 is a top view of a vehicle C including a start control device according to a first embodiment, and shows a schematic configuration of the vehicle C. FIG. It is a block diagram which shows the structure of the vehicle control controller 14 of 1st embodiment. 3 is a block diagram showing a configuration of ABS control means 28. FIG. 3 is a block diagram showing a configuration of acceleration comparison means 48. FIG. It is a flowchart which shows the process of the starting control apparatus of 1st embodiment. It is a time chart which shows operation | movement of the vehicle C provided with the starting control apparatus of 1st embodiment. It is a block diagram which shows the structure of the vehicle control controller 14 of 2nd embodiment. 3 is a block diagram showing a configuration of a braking force determination means 68. FIG. It is a flowchart which shows the process of the starting control apparatus of 2nd embodiment. It is a time chart which shows operation | movement of the vehicle C provided with the starting control apparatus of 2nd embodiment. It is a block diagram which shows the structure of the vehicle control controller 14 of 3rd embodiment. 4 is a block diagram showing a configuration of a driving force determination unit 76. FIG. It is a flowchart which shows the process of the starting control apparatus of 3rd embodiment. It is a time chart which shows operation | movement of the vehicle C provided with the starting control apparatus of 3rd embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine 2 Front wheel 8 Motor 10 Rear wheel 12 Acceleration detection means 14 Vehicle control controller 16 Accelerator pedal 18 Clutch 22 Front wheel speed sensor 24 Front wheel brake device 26 Brake pedal 28 ABS control means 38 Rear wheel speed sensor 40 Rear wheel brake device 42 Motor control Means 46 4WD controller 50 Engine control means 52 Clutch control means 54 Vehicle speed calculation section 56 Lock detection section 58 Required braking force calculation section 60 Hydraulic control section 64 Acceleration calculation means 68 Braking force determination means 70 Required braking force detection means 76 Driving force Determination means 78 Required driving force detection means C Vehicle

Claims (6)

An engine that drives one of the front wheels and the rear wheels of the vehicle, a motor that drives the other of the front wheels and the rear wheels, and an ABS control that controls the braking force so as to suppress locking of the front wheels and the rear wheels And an engine start control device provided in a vehicle comprising:
Engine control means for controlling the driving state of the engine;
The engine control means stops the engine according to a driving force requested by a driver during driving of the motor, and further stops when the ABS control means is operated in a state where the engine is stopped. An engine start control device, wherein the engine is started during operation of the ABS control means. Acceleration detecting means for detecting acceleration in the deceleration direction of the vehicle, and acceleration calculating means for calculating acceleration in the deceleration direction on the reference road surface of the vehicle,
The engine control means is such that the acceleration in the deceleration direction detected by the acceleration detection means during operation of the ABS control means is less than the acceleration in the deceleration direction calculated by the acceleration calculation means during operation of the ABS control means. 2. The engine start control device according to claim 1, wherein in some cases, the stopped engine is started during operation of the ABS control means. A clutch control means for controlling a clutch for connecting or releasing the engine and the engine driving wheel via a driving force transmission path between the engine and the engine driving wheel driven by the engine;
The clutch control means releases the engine and the engine driving wheel while the ABS control means is operating, and connects the engine and the engine driving wheel when the operating ABS control means stops. The engine start control device according to claim 1 or 2. Requested braking force detection means for detecting a braking force requested by the driver; and braking force determination means for determining whether or not the braking force detected by the requested braking force detection means is equal to or less than a predetermined braking force. Prepared,
When the ABS control unit in operation is stopped and the braking force determination unit determines that the braking force detected by the required braking force detection unit is equal to or less than a predetermined braking force, the clutch control unit The engine start control device according to claim 3, wherein the engine drive wheel is connected. Requested driving force detecting means for detecting the driving force requested by the driver; and driving force determining means for determining whether or not the driving force detected by the requested driving force detecting means is equal to or greater than a predetermined driving force. Prepared,
When the ABS control unit in operation is stopped and the driving force determination unit determines that the driving force detected by the required driving force detection unit is equal to or greater than a predetermined driving force, the clutch control unit The engine start control device according to claim 3 or 4, wherein the engine drive wheel is connected. The driving state of the engine that drives one of the front wheel and the rear wheel of the vehicle, the driving force requested by the driver, and the operating state of the ABS control means for controlling the braking force so as to suppress the locking of the front wheel and the rear wheel An engine start control method for controlling according to
Stop the engine according to the driving force requested by the driver,
When the ABS control means is operated while the engine is stopped while the motor for driving the other of the front wheels and the rear wheels is being driven, the stopped engine is started during the operation of the ABS control means. An engine start control method.

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