JP3402638B2 - Vehicle drive system - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving apparatus for a vehicle which is driven by using a motor in addition to an engine. 2. Description of the Related Art In recent vehicles, four-wheel drive vehicles tend to increase, but one of right and left front wheels and right and left rear wheels is driven by an engine to reduce weight and the like. In some cases, the main drive wheel is used, and the other wheel is used as an auxiliary drive wheel driven by a motor. Japanese Patent Application Laid-Open No. 2-120136 discloses two different driving forces.
There has been proposed a motor that uses one motor to change the type and number of motors to be operated in accordance with the gear position of the transmission, that is, a motor that changes the auxiliary driving force of the motor. Japanese Patent Laying-Open No. 57-74222 discloses that the distribution of hydraulic pressure to two right and left hydraulic motors (hydraulic cylinders) is automatically performed according to the road load applied to the left and right auxiliary drive wheels. In addition, a device having a function of a differential device has been proposed. Japanese Unexamined Patent Publication (Kokai) No. 63-38031 discloses the use of two electric motors on the left and right sides. The higher the vehicle speed, the larger the generated voltage and the constant the generated torque of the motor. With the manual switch,
There has been proposed an apparatus which can switch between driving execution and driving stop by a motor. [0005] By the way, the assisting of driving by the motor is preferable in that the driving force is effectively transmitted to the road surface, but the driving energy of the motor is ultimately reduced. Since it depends on the engine, it is not preferable from the viewpoint of improving fuel efficiency. In addition, two wheel drive state and 4
In many cases, there is a difference in vehicle characteristics such as straight running stability and turning characteristics between the wheel drive state. From the above viewpoint, it is conceivable that the motor is driven only when a predetermined condition set in advance is satisfied, for example, only in a minimum necessary area such as during acceleration. On the other hand, the vehicle normally performs not only forward traveling but also backward traveling. Therefore, the area in which the motor drive is performed when the vehicle is traveling backward is determined in accordance with the setting of the motor drive area when the vehicle is traveling forward.
This is important in increasing the usefulness of this type of vehicle. SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a vehicle drive device in which a region for driving an auxiliary drive wheel by a motor can be more appropriately set as a whole, including when the vehicle is moving forward and backward. The purpose is to provide. Means for Solving the Problems To achieve the above object, the present invention has the following configuration. That is, one of the left and right front wheels and the left and right rear wheels is a main drive wheel driven by the engine via a transmission and a differential, and the other wheels are independently left and right by the motor. An auxiliary drive wheel to be driven, which is a vehicle that performs forward drive for driving a motor in a forward direction under predetermined conditions when the vehicle advances, and inhibits the forward drive when decelerating. At the time of normal driving, a target vehicle speed is determined based on predetermined conditions using at least the accelerator opening and the gear position of the transmission as parameters, and a motor is used based on the difference between the determined target vehicle speed and the actual wheel speed. When it is determined whether or not drive assist is required, and when it is determined that assist drive is necessary, a driving force of the motor in the forward direction is generated so as to reach the target vehicle speed, while it is determined that auxiliary drive is unnecessary. To the motor First control means for controlling to prohibit auxiliary driving; and when the vehicle is moving backward, the driving force is always independently supplied to the left and right motors in a direction for assisting the vehicle to move backward regardless of the predetermined condition. And a second control means for generating. According to the present invention, the target vehicle speed is determined on the basis of predetermined conditions regarding the accelerator opening and the gear position of the transmission when the vehicle travels forward with a long running time, and the target vehicle speed and the actual vehicle speed are determined. When it is determined that auxiliary driving by the motor is necessary based on the difference from the wheel speed, control is performed such that auxiliary driving is performed by generating a motor driving force in the forward direction of the vehicle so as to reach the target vehicle speed. When it is determined that driving is unnecessary, control is performed so as to prohibit auxiliary driving by the motor.
This is preferable in terms of improving fuel efficiency by eliminating unnecessary motor driving assistance. Further, when the vehicle is moving backward, the motor always assists the vehicle in moving backward, so that the vehicle can reliably travel when moving backward. When the vehicle is moving backward, the running time is extremely short and the vehicle speed is low. Therefore, even if the motor is always driven during the reverse movement, there is no problem that the fuel consumption and the characteristics of the vehicle are adversely affected. In addition, when reversing, the steering wheel is often operated greatly, such as when entering the garage or parking, but since the left and right motors are individually driven and controlled, it should be possible to cope with a large operation of the steering wheel. Become. DESCRIPTION OF THE PREFERRED EMBODIMENTS Hydraulic system, etc. (FIG. 1) In FIG. 1, 1FL is a front left wheel, 1FR is a front right wheel, 1R
L is a left rear wheel, and 1RR is a right rear wheel. An engine 2 is disposed in front of the vehicle body, and a driving force of the engine 2, that is, a generated torque is transmitted to a differential device 5 via a clutch 3, a manual transmission 4 having five forward speeds and one reverse speed. Then, the left front wheel 1FL is output from the differential device 5 via the left drive shaft 6L.
The engine driving force is transmitted to the right front wheel 1FR via the right drive shaft 6R. The left and right front wheels 1FL and 1FR to be steered are linked by a steering link 7 such as a tie rod, and the steering link 7 and the handle 8 are linked via a rack and pinion mechanism 9. The left and right rear wheels 1RL, 1RR are
Separately and independently, a pair of left and right hydraulic motors ML, MR
It is adapted to be driven by. That is, the left rear wheel 1RL is connected to the left motor M via the left drive shaft 11L.
L, and the right rear wheel 1RR is driven by the right drive shaft 11
Driven by the right motor MR via R. This motor ML, that is, the left drive shaft 11L
And the motor MR, that is, the right drive shaft 11R, are separated from each other so that the left and right can be driven independently. The left and right drive shafts 11L and 11R are
The hydraulic clutch 12 is capable of intermittent operation. The motor ML (MR) is of a turbine type (impeller type) and has a first connection port La (Ra) and a second connection port Lb (Rb), and La (Ra). ) To Lb (Rb)
When the high-pressure oil liquid flows to the
When the high-pressure oil liquid flows in a direction opposite to this, the rotation is made in the backward direction. The motors ML and MR have the same specifications, and the total value of the maximum generated torque is about 1/3 to 1/2 of the maximum generated torque of the engine 2. In the embodiment, the rear wheel drive by the motors ML and MR is executed only under predetermined conditions described later. That is, the left and right front wheels 1FL,
Even when 1FR is driven, the left and right rear wheels 1RL, 1RL
RR may not be driven by the motors ML and MR. P is a pump as a hydraulic pressure generating source. The pump P is of a variable displacement type, and has an output shaft 2 of the engine 2.
The drive pulley 13, the belt 14, and the driven pulley 15 drive the drive pulley 13a. The high-pressure oil pumped by the pump P from the reservoir tank 16 is discharged to a high-pressure line 18 to which a check valve 17 is connected. From this high-pressure line 18, first and second hydraulic pressure supply lines 31A and 31B connected to the check valve 10 or 32 are connected in parallel. Further, a release line 23 extends from the reservoir tank 16.
Furthermore, each connection port La, Lb (R) of the motor ML (MR)
a, Rb), the parallel lines 20L, 21L
(20R, 21R) are derived. Lines 20L and 21L of the left motor ML are provided with a switching valve VVA, mutually parallel lines 19 and 19L and lines 22 and 22L, and switching valves VVB · L and VVE ·.
L, the first supply line 31A and the release line 23
Can be selectively connected to. Similarly, lines 20R and 21R of the right motor MR are connected to the switching valves VVA,
Lines 19, 19R and lines 22, 22 parallel to each other
R, and switching valves VVB • R, VVE • R,
The first supply line 31A and the release line 23 can be selectively connected. A switching valve VVI is connected to the second common supply line 31B on the downstream side of the check valve 32, and a flow dividing valve 34 is connected on the downstream side. One branch supply line 33L branched into two by the branch valve VVI is connected to the line 19L, and the other branch supply line 33R is connected to the line 19R. An accumulator 41 for storing high-pressure oil pressure is connected to the high-pressure line 18. For this high pressure line 18, a line 20L (20R)
Are connected by a passage 42L (42R). This passage 42L (42R) has a check valve 43L (43
R) and the switching valve VVF · L (VVF · R) are connected. The passages 43L and 43R are parallel to each other, and each of the valves VVA, VVB · L (VVB · R), VVE · L (V
VE · R), VVI, the flow dividing valve 34 and the like are bypassed. The line 20L (20R) and the line 21
L (21R) is communicated with a communication path 51L (51R), and a variable orifice VVC · L (VVC · R) is connected to the communication path 51L (51R). An actuator for connecting and disconnecting the clutch 12 is indicated by reference numeral 61. This actuator 61
Supply line 62 for high pressure line 18 and discharge line 63 for release line 23, switching valve VVJ
And the two lines 62 and 63 can be shut off by the switching valve VVJ. The left and right motors ML and MR are connected to each other by a communication passage 71.
VD is connected. The release line 23 is connected to the high pressure line 18 on the upstream side (pump P side) of the check valve 17 via a load / unload valve VVH and on the downstream side of the check valve 17. Are connected via a safety valve VVG. Description of Control Modes (Table 1) This embodiment has a total of eight types of control modes, as will be described later, and controls each of the above-described valves when each mode is executed. The operating conditions are summarized in Table 1 below. In this table, symbols “L” and “R” for identifying left and right are omitted. The load / unload valve VVH not shown in Table 1 is controlled to open and close so that the pressure in the high pressure line 18 falls within a predetermined pressure range between a lower limit and an upper limit. [Table 1] In each control mode shown in Table 1, the operating state of the valve which performs the main function will be specifically described.
It is as follows. (1) Integrated mode In the integrated mode, the drive control of the motors ML and MR is performed so that the left and right rear wheels 1RL and 1RR have the same rotational speed, as will be described in detail later. There are two types, drive (drive assist) and reverse drive (braking). In this integration mode,
The clutch 12 is engaged (the switching valve VVJ opens the line 62 and closes the line 63), and the switching valve VVB · L (V
VB · R), VVE · L (VVE · R) and VVI are in the state shown in FIG. In this state, the switching valve VVA is controlled to switch the hydraulic pressure supply direction according to the forward drive or the reverse drive (setting the forward and reverse directions of the motors ML and MR) and to control the motors ML and MR. The supply flow rate is controlled (hydraulic supply using the first supply line 31A).
In the reverse drive, a larger deceleration is obtained than in the hydraulic lock mode described later. However, it is natural that the rear wheels 1RL and 1RR rotate in a direction opposite to the traveling direction of the vehicle. It does not provide any driving force. (2) Independent mode The independent mode is such that the motor ML is such that the left and right rear wheels 1RL and 1RR have the target rotational speeds set independently of each other, as will be described in detail later. , MR drive control, and there are two types of forward drive and reverse drive as in the case of the integrated mode. In this independent mode, the clutch 12 is released (the switching valve VVJ closes the line 62 and opens the line 63). Switching valve VVE-L (VVE-R)
Is operated as shown in FIG. 1, but the switching valve VVA
Is set to the center switching position and the first supply line 31A is shut off. The switching valve VVI is set to the open position, and the hydraulic pressure is supplied using the second supply line 31B. In this state,
By controlling the switching valve VVB · L (VVB · R), switching of the hydraulic pressure supply direction according to forward drive or reverse drive (motor M
L, MR forward and reverse directions) and motors ML, M
The supply flow rate for R is controlled. (3) LSD mode The LSD mode is for obtaining a differential limiting function.
VB · L and VVB · R are connected to lines 20L and 21L (2
0R, 21R) are both closed to completely shut off the supply and discharge of hydraulic pressure to the motors ML, MR. And
The on-off valve VVD is opened, and the closed left and right hydraulic paths of the motors ML and MR communicate with each other to form the left and right motors.
This prevents a large rotation difference between the data ML and MR. In this LSD mode, the variable orifice VV
C · L (VVC · R) is fully closed. Since this LSD mode is not directly related to the present invention,
A more detailed description will be omitted. (4) Hydraulic lock mode The hydraulic lock mode has a passage resistance, that is, a variable orifice V
A deceleration force using the throttle resistance of VC · L (VVC · R) is obtained. In this hydraulic lock mode, the switching valve V
VB · L and VVB · R are in the center switching position, the lines 20L, 21L, 20R and 21R are shut off, and the on-off valve VVD is closed. And the variable orifice V
VC · L and VVC · R are opened. In this state, the oil liquid is circulated through the closed hydraulic circuit including the variable orifice VVC · L (VVC · R) according to the rotation of the motor ML (MR). Is a variable orifice VVC · L (VVC · R) through which the oil liquid passes during circulation.
The throttle resistance gives a deceleration force to the vehicle. The degree of opening of the variable orifices VVC · L and VVC · R is controlled to decrease as the deceleration of the vehicle increases (variable orifices VVC · L, V corresponding to the deceleration).
The setting of the VC / R opening is exemplified in step E37 in FIG. 3). Note that the clutch 12 may be in either the engaged state or the released state. (5) Accumulation mode In the accumulation mode, the vehicle, that is, the rear wheels 1RL, 1R
The motors ML and MR driven by R function as pumps to accumulate pressure in the accumulator 41. In this pressure accumulation mode, the line 21L (21R) communicates with the reservoir tank 16 while the on-off valve VVF · L
When (VVF.R) is opened, the oil liquid in the reservoir tank 16 is pumped up by the motor ML (MR) and accumulated in the accumulator 41. (6) Stop mode The stop mode is a mode in which the motors ML and MR stop the vehicle when the parking brake is not operating.
(The driving of the motors ML and MR is controlled so that the vehicle speed becomes the target vehicle speed 0). In this case, the hydraulic pressure supply line uses the second supply line 31B, and the supply / discharge control of the hydraulic pressure is performed by the switching valve VVB · L (VVB · L).
R). (7) Parking Mode The parking mode enhances the action of maintaining the parking state when the parking brake is activated. That is, in the parking mode, the switching valve VVB · L
(VVB · R) is set to the closed position of the center switching position, the hydraulic supply / discharge line is cut off, and the clutch 12 is engaged. (8) F / S mode The F / S mode is a fail-safe mode. When there is any abnormality, for example, when the high-pressure line becomes abnormally high, the mode is changed. -When the valves ML and MR are not driven normally, when a certain valve is stuck, or when the oil temperature becomes higher than a predetermined temperature, and the like, the safety valve VVG is opened, The oil pressure in the high pressure line 18 is released. Description of Control System (FIG. 2) FIG. 2 shows a control system in the present invention. In the figure, U1 and U2 are control units each configured using a microcomputer, and the control unit U1 is a main control unit for controlling the above-described valves VVA and the like. The control unit U2 is for ABS control (anti-lock brake control). Also, S1 to S10 are
Each is a sensor or a switch. The sensors S1 to S4 are provided for each wheel 1FL to 1R.
The rotation speed of R, that is, the wheel speed is independently detected, and the wheel speed detected by each of the sensors S1 to S4 is transmitted from the control unit U2 to the control unit U1. The sensor S5 detects the vehicle speed. In the embodiment, the sensor S5 detects the ground vehicle speed (detection of the absolute vehicle speed). The sensor S6 detects a shift position of the transmission 4, that is, a gear position. The sensor S7 detects the engine speed. The sensor S8 detects the steering angle of the steering wheel. The sensor S9 detects the accelerator opening. The sensor S10 detects the depression amount of the brake pedal. The signals from the sensors or the switches S5 to S10 are input to the control unit U1, and the control unit U1 controls the above-described valves VVA to VVJ. Of course, the control unit U2 is for preventing the wheels from locking during braking, and the control unit U2 provides a brake hydraulic pressure for independently adjusting the braking of each wheel. A control signal is output to adjusting means 81. The wheel speed signals detected by the sensors S1 to S4 are transmitted from the control unit U2 to the control unit U1,
The signals from the sensors S1 to S4 may be directly input to the control unit U1. Description of Flowchart (FIG. 3) Next, the control contents of the control unit U1 will be described with reference to the flowchart of FIG. Each step is shown. First, E2 in FIG.
In 1, after signals from each sensor and the like are read, E
At 22, it is determined whether or not the vehicle is traveling backward.
This determination is made, for example, by checking whether or not the shift position of the transmission 4 is in the reverse gear position. If the determination in E22 is YES, E
At 23, normal driving in the independent mode described later is performed. If the determination in E22 is NO, it is determined in E24 whether the vehicle is traveling forward. This determination is made by checking whether or not the shift position of the transmission 4 is in a state where the forward gear is selected. E2
If the determination in step 4 is NO, the transmission 4 is in the neutral position. In this case, the transmission is returned as it is. If the determination in E24 is YES, the control after E26, which is the control content at the time of forward movement, is appropriately performed. Note that the transmission 4 is not in the new state without the determination of E24.
The process of E26 and below may also be performed by regarding that the vehicle is moving forward when the vehicle is in the neutral position. At E26, it is determined whether the vehicle is currently traveling straight. In this embodiment, whether or not the vehicle is traveling straight is determined by calculating the lateral G based on the steering angle and the vehicle speed, and determining that the vehicle is traveling straight when the lateral G is equal to or less than a predetermined value. If the determination in E26 is YES, E27-
The process of E39 is performed. Finally, control conditions for performing the forward drive (E28) and reverse drive (E35) in the integrated mode, the accumulation mode (E33, E39) or the hydraulic lock mode (E31, E37) are satisfied. Is determined. The degree of acceleration and the degree of deceleration can be determined by various known methods. For example, the degree of acceleration
It can be known from any one or a combination of any two or more of the accelerator pedal depression speed, the accelerator pedal depression amount increase amount, and the vehicle body acceleration obtained by differentiating the vehicle speed. The degree of deceleration is, for example, any one of a magnitude of an accelerator release speed, a magnitude of a brake depression speed, an increase in a brake depression amount, a vehicle deceleration obtained by differentiating a vehicle speed, and the like. Alternatively, it can be known by arbitrary plural combinations. However, in the embodiment, at least when the accelerator return speed is high (when the accelerator release speed is high), it is determined that the deceleration is equal to or more than the slow deceleration for setting the hydraulic lock mode. If NO in the determination of E26 in FIG.
FIG. 4 is based on the assumption that the vehicle is turning. Finally, it is determined whether the control conditions for performing the forward drive (E42) and the reverse drive (E44) or the LSD mode (E45) in the independent mode are satisfied. Description of the flowchart (FIG. 5) FIG. 5 shows details of the positive drive control in the independent mode. The positive drive control in the integrated mode is substantially different from the positive drive control in the independent mode only in that the same target vehicle speed is provided for the left and right rear wheels and in that control is performed by the switching valve VVA. The same is done. First, after data is input at Z1, a target vehicle speed VTR is set at Z2 using the accelerator opening and the shift position of the transmission 4 as parameters. Next, at Z3, it is determined whether or not a value obtained by subtracting the actual wheel speed VBL of the left rear wheel 1RL from the target vehicle speed VTR is higher than a predetermined speed V1. When the determination in Z3 is NO, it is determined that the drive assist by the forward drive is not necessary, and the forward drive of the left rear wheel is stopped in Z13. The processing of Z3 and Z13 is performed for the right rear wheel 1RR independently of the left rear wheel 1RL. The predetermined speed V1 is set to a speed indicating a slip amount sufficient for acceleration, but may be a constant value or a variable value that increases as the vehicle speed VA increases. If the determination in Z3 is YES, it is determined whether or not the accelerator is fully closed in Z4. If the determination in Z4 is YES, the motor M
It is determined that driving assistance using L and MR is not necessary, and the process proceeds to Z13 (in this case, the left and right rear wheels 1R
L and 1RR are stopped at the same time. If the determination in Z4 is NO, in Z5, the lateral G acting on the vehicle body is calculated based on the vehicle speed VA and the steering angle. Thereafter, in Z6, the correction coefficients k1 and k2 are set. Then, in Z7, it is determined whether or not the vehicle is turning right. If the determination in Z7 is YES, in Z9, the left rear wheel 1RL
Is the target vehicle speed VTR determined by Z2.
TR is calculated by multiplying TR by a correction coefficient k1, and similarly, target wheel speed VTRR of right rear wheel 1RR is calculated by multiplying target vehicle speed VTR by correction coefficient k2. If NO in Z7, the target wheel speeds of the left and right rear wheels 1RL, 1RR are calculated in Z8. In short, the processing of Z6 to Z9 corresponds to processing of increasing the target wheel speed on the turning outer wheel side and decreasing the target wheel speed on the turning inner wheel side. However, when the vehicle is going straight, the determination of Z7 is NO and the process proceeds to Z8. At this time, since the correction coefficient is 1, the horizontal G is 0 or almost 0.
), The target wheel speeds of the left and right rear wheels 1RL, 1RR are made equal to each other. After Z8 or Z9, at Z10, the target wheel speed VTRL (VTRR) is changed from the rear wheel 1RL.
(1RR) The amount of oil liquid Q supplied to the motor ML (MR) according to the value obtained by subtracting the actual wheel speed VBL (VBR).
Is determined. This oil liquid amount Q is determined by the left and right motors ML, M
R is determined independently of each other. Then, in Z11, the switching valves VVB · L and VVB · R are individually controlled so as to realize the determined oil liquid amount Q. At Z12, it is determined whether or not a value obtained by subtracting the actual wheel speed VBL of the left rear wheel 1RL from the vehicle speed VA is smaller than a predetermined speed "-V2". This Z
In the end, the determination of 12 is to determine whether or not the actual wheel speed VBL of the left rear wheel 1RL is too high compared to the vehicle speed VA. If the determination of Z12 is YES, Z1
In 3, so that the rear wheel maintains a predetermined slip value,
Correction for reducing the supply flow rate Q is performed. Note that Z1
2, the processing of Z13 is similarly performed for the right rear wheel 1RR. If the determination in Z12 is NO, Z13
Is returned without going through. In the positive drive control in the integrated mode, Z
5 to Z9 become unnecessary, and the target vehicle speed VTR determined in Z2 becomes the target wheel speed VT of the left and right rear wheels 1RL, 1RR.
RL and VTRR. In addition, a switching valve VVA is used to realize the flow rate Q at Z11. Description of Flowchart (FIG. 6) FIG. 6 shows details of the reverse drive in the independent mode. The positive drive control in the integrated mode is the same as the positive drive control in the independent mode except that the switching valve used for flow rate adjustment is different from the switching valve used in the independent mode. It is performed as follows. First, after data is input at Z21, it is determined at Z22 whether or not the reverse drive flag is 1. When the determination of Z22 is NO,
In Z30, the steering angle and the vehicle speed VA are parameters.
A confirmation is made as to where the current state is in the area set as the data. Thereafter, in Z31, it is determined whether or not the current state is in the hatched C area in the area shown in Z30. If the determination in Z31 is YES, the reverse drive flag is set to 1 in Z32, and the process returns to Z21. If the determination in Z31 is NO, Z
Return to Z21 without going through 32. After passing through Z32, the determination of Z22 is YE
At this time, it is determined in Z23 whether or not the ABS control is currently being performed. In the determination of Z23, N
In the case of O, it is determined in Z24 whether or not the brake depression amount is large. NO in this determination of Z25
, The vehicle speed VA is increased to a predetermined value V at Z25.
It is determined whether or not the vehicle speed is 3 or less. If the determination in Z25 is NO, Z2
At 6, the supply flow rate Q to the motors ML and MR is determined using the vehicle speed VA and the shift position of the transmission 4 as parameters. Thereafter, in Z27, the switching valves VVB · L and VVB · R are controlled such that the flow rate Q determined in Z26 is supplied to the left and right motors ML and MR. Z2
After step 7, the processing of Z28 and Z29 is performed. This processing corresponds to the processing of Z12 and Z13 in FIG. 9 and is a processing for correcting that the reverse driving force becomes too large. If the determination in any of the above Z23, Z24 and Z25 is YES, after the reverse drive control is stopped in Z33, the reverse drive flag is reset to 0 in Z34. The reverse drive control in the integrated mode is based on Z26.
VVA is used as a switching valve for realizing the flow rate Q determined in the above. Although the embodiment has been described above, the present invention is not limited to this and includes, for example, the following case. (1) The reverse drive may not be performed during forward running. (2) The left and right rear wheels 1RL and 1RR may be driven by the engine 2, and the left and right front wheels 1FL and 1FR may be driven by the motors ML and MR. (3) The motors ML and MR may be electrically driven. (4) The motors may not be provided independently for the left and right, but may be provided for only one common to the left and right. (5) The reverse drive may be prohibited during the execution of the ABS control. In this case, an ABS signal indicating that the ABS control is being executed is transmitted to the control unit U1. (6) When the vehicle is moving forward, the positive drive area of the motor is
(Enlargement or reduction) in accordance with the above. For example, the motor may be driven forward even during slow acceleration.
In this case, the μ signal indicating the road surface μ is transmitted to the control unit U2
May be transmitted to U1 or a signal from a μ sensor provided separately may be directly input to the control unit U1.

[Brief description of the drawings] FIG. 1 is a diagram showing an example of a hydraulic system used in the present invention. FIG. 2 is a diagram illustrating an example of a control system. FIG. 3 is a flowchart showing a control example of the present invention. FIG. 4 is a flowchart showing a control example of the present invention. FIG. 5 is a flowchart showing a control example of the present invention. FIG. 6 is a flowchart showing a control example of the present invention. [Explanation of symbols] U1: Control unit (for motor control) U2: Control unit (for ABS control) P: Pump ML, MR: Motor 1FL, 1FR: Front wheel 1RL, 1RR: rear wheel 2: Engine 4: Transmission 5: Differential device

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-60-64035 (JP, A) JP-A-64-7701 (JP, A) JP-A-4-76527 (JP, U) 8821 (JP, Y1) (58) Field surveyed (Int. Cl. ⁷ , DB name) B60K 17/356 B60K 17/04 F16H 61/40

Claims (1)

(57) [Claim 1] One of the left and right front wheels and the left and right rear wheels is a main drive wheel driven by an engine via a transmission and a differential, and the other is The left and right wheels are independent driving wheels driven by the motor independently of the left and right ,
When the motor is driven in the forward direction under predetermined conditions
Driving and prohibiting the forward driving during deceleration
A vehicle that has at least the accelerator opening and the gear position of the transmission at the time of forward drive during forward movement of the vehicle, based on predetermined conditions using parameters as parameters.
The target vehicle speed is determined, and the determined target vehicle speed and the actual vehicle are determined.
Whether motor assist is necessary based on the difference from wheel speed
And when it is determined that auxiliary driving is necessary, the target
Generates the driving force of the motor in the forward direction to achieve the vehicle speed.
On the other hand, when it is determined that auxiliary driving is unnecessary,
First control means for controlling so as to prohibit auxiliary driving; and when the vehicle is moving backward, regardless of the predetermined condition,
The left and right motors are independent of each other in the direction to assist the vehicle in reverse.
And a second control means for generating a driving force by standing .