JP2003312279A - Driving device for front and rear wheel driven vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a drawing-out operation at a more upstream side segment than an electromagnetic clutch intermittently connecting or disconnecting between the electric motor and rear wheels caused by a drawing-out torque at a driving device for driving rear wheels by an electric motor independent from an engine acting as a driving means for front wheels. <P>SOLUTION: This driving device includes a drawing-out prevention means for preventing a drawing-out at a more upstream side than an electromagnetic clutch caused by a drawing-out torque at the electromagnetic clutch. The drawing-out of an electric motor and the like caused by a drawing-out torque at the electromagnetic clutch is prevented by performing a drawing-out prevention control. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive device for front and rear wheel drive vehicles.

[0002]

2. Description of the Related Art As one type of drive device for an automobile, one of the front and rear wheels, the main drive wheel side, is driven by the main drive means, and the other of the front and rear wheels, the sub drive wheel side, is the auxiliary drive means. There are drive devices for front and rear wheel drive vehicles of the driven type. The drive device of this type drives the main drive wheels by the main drive means during normal traveling to form an independent drive traveling state of the main drive wheels, and when the vehicle is starting or traveling at low speed, By driving the auxiliary drive means, both the front and rear wheels (main drive wheel and auxiliary drive wheel) of the automobile are driven together to form a front and rear two-wheel drive traveling state. It is proposed in Japanese Patent No. 253256 under the name of "vehicle drive device".

Specifically, the vehicle drive system is a system in which the front wheel side is driven by an engine which is a main drive means, and the rear wheel side is driven by an electric motor which is an auxiliary drive means, and is driven by the engine. A first generator, a low-voltage battery that stores the electric power generated by the first generator, and a second generator that is driven by the engine are provided, and the electric power generated by the second generator is supplied to the electric motor. It is configured to drive the rear wheel side.

According to the vehicle drive device, a long drive transmission mechanism such as a long drive shaft for transmitting the driving force of the engine to the rear wheels, which is indispensable in a normal four-wheel drive vehicle, is provided. It becomes unnecessary, and the weight of the vehicle can be reduced and the energy can be largely saved.

[0005]

By the way, in this type of drive unit, as is recognized in the above-mentioned vehicle drive unit, a clutch is provided between the auxiliary drive wheel side driven by the electric motor and the electric motor side. When the auxiliary drive wheel side is in a non-driving state due to the presence of the clutch, the clutch disconnects the connection state between the auxiliary drive wheel side and the electric motor capable of transmitting driving force, and drives the auxiliary drive wheel side. When brought into the state, the auxiliary drive wheel side and the electric motor side are connected by the same clutch so that the driving force can be transmitted.

In the drive device having such a structure, in order to bring the auxiliary drive wheel side in the drive state into the non-drive state, the coupling state between the auxiliary drive wheel side and the electric motor is cut off by the clutch. In that case, drag torque is generated in the clutch, and the drag torque may cause the electric motor to circulate, which may cause wear of motor components and bearings.

Therefore, an object of the present invention is, in a drive device for a front-rear wheel drive vehicle of this type provided with the clutch, a connection state capable of transmitting driving force between the auxiliary drive wheel side and the auxiliary drive means by the clutch. The purpose is to prevent the occurrence of whirling due to the drag torque in the clutch when the clutch is disengaged.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a drive system for a front and rear wheel drive vehicle. A drive device according to the present invention includes a main drive unit that drives one of the front and rear wheels on the main drive wheel side, a sub drive unit that drives the other of the front and rear wheels on the sub drive wheel side, and the sub drive unit. A clutch that connects and disconnects the drive force transmission with the sub drive wheel side is provided, and when the sub drive wheel side is driven, the drive force can be transmitted between the sub drive means and the sub drive wheel side by the clutch. Is a drive device for a front-rear wheel drive vehicle of a type which is connected to the auxiliary drive means to drive the auxiliary drive wheel side.

Therefore, the drive device for the front and rear wheel drive vehicle according to the present invention is capable of transmitting the drive force between the auxiliary drive means and the auxiliary drive wheel side in the drive device for the front and rear wheel drive vehicle of the above-mentioned type. It is characterized in that it is provided with means for preventing whirling of an upstream side of the clutch due to a drag torque in the clutch when the connection state is disconnected by the clutch.

In the drive device for a front-rear wheel drive vehicle according to the present invention, the whirling prevention means is applied with a torque in a direction opposite to the drag torque of the clutch, and the whirling movement of the auxiliary drive means is set to a predetermined value. The auxiliary drive means may be configured to have the following structure, and a braking force may be applied to the auxiliary drive means to reduce the rotation of the auxiliary drive means to a predetermined value or less. It may be a brake mechanism or a lock mechanism interposed between the means and the clutch.

In the drive device for a front and rear wheel drive vehicle according to the present invention, an electric motor is adopted as the sub drive means for driving the other side of the front and rear wheels, the sub drive wheel, and a drive source for the sub drive means. As the electric power generating means, it is possible to employ a generator driven by the main driving means to generate electric power as a drive source of the electric motor.

[0012] In the drive device, the whirling prevention means may be configured to control the power generated by the generator to generate a regulation force for regulating the rotation of the electric motor. In addition, in the drive device, a generator having a variable generated voltage is adopted as the generator, the generator supplies electric power to the electric motor when driving the auxiliary drive wheels, and the generator is used when preventing whirling. Power can be supplied to the electric motor from a low-voltage battery that stores the electric power.

Further, in the drive device for the front-rear wheel drive vehicle according to the present invention, as the electric motor as the auxiliary drive means,
An electric motor capable of selectively switching between mechanical energy and electric energy and outputting the electric energy can be employed, and regenerative electric power generated by the electric motor can be used as a drive source for the electric motor. The drive device may be configured to supply regenerative electric power, which is a power source different from the generator, to the electric motor to generate a braking force.

[0014]

As described above, the drive device for a front-rear wheel drive vehicle according to the present invention, when disconnecting the connection state capable of transmitting the driving force between the auxiliary drive means and the auxiliary drive wheel side by the clutch, The clutch is equipped with a whirling prevention means for preventing whirling of an upstream side portion of the clutch due to a drag torque. Therefore, according to the drive device, when disconnecting the driving force transmittable connection state between the auxiliary drive wheel side and the auxiliary drive means by the clutch, a portion upstream of the clutch due to the drag torque in the clutch is generated. It is possible to prevent running around, and thereby to prevent wear of components, bearings, and the like on the side of the auxiliary drive unit due to drag torque of the clutch.

In the front and rear wheel drive device according to the present invention,
Depending on the type of driving the sub-driving unit, the whirling prevention unit can have an appropriate configuration corresponding to the type. The whirling prevention means is configured, for example, to apply a torque in a direction opposite to the drag torque of the clutch to the sub driving means to reduce the whirling of the sub driving means to a predetermined value or less, and to apply a braking force to the sub driving means. As a result, a configuration in which the rotation of the sub drive unit is reduced to a predetermined value or less, or a configuration in which a brake mechanism or a lock mechanism is interposed between the sub drive unit and the clutch can be adopted.

In the drive device for a front and rear wheel drive vehicle according to the present invention, an electric motor is adopted as a sub drive means for driving the other side of the front and rear wheels, that is, the sub drive wheel, and the drive source for the sub drive means. As the electric power generation means, it is possible to adopt a configuration in which a generator driven by the main drive means to generate electric power as a drive source of the electric motor is adopted.
In the drive device, needless to say, each of the above-mentioned whirling prevention means can be adopted, but the whirling prevention means generates the regulation force for controlling the electric power generated by the generator to regulate the rotation of the electric motor. It can be configured to.

In this case, a generator having a variable generated voltage is adopted as the generator, the electric power is supplied from the generator to the electric motor when the auxiliary drive wheels are driven, and the electric power of the generator is stored when the whirling prevention is performed. It can be configured to power the electric motor from a low voltage battery.

Furthermore, in the drive unit according to the present invention, an electric motor capable of selectively switching between electric energy and mechanical energy for output can be adopted as the sub-driving means. In such a case, Can be configured to supply electric power to the electric motor from a power supply path different from the power supply system path from the generator to generate a braking force.

Conventionally, as means for preventing whirling due to drag torque of the clutch of the electric motor, means for setting the friction torque of the electric motor to be larger than the drag torque of the clutch has been adopted. The friction in the electric motor is large and the loss when driving the motor is large. However, in the front and rear wheel drive device according to the present invention, since each of the above-mentioned whirling prevention means that does not rely on the friction of the auxiliary drive means such as the electric motor is adopted,
It is possible to reduce the loss of the auxiliary drive unit such as the electric motor during normal driving, and it is possible to accurately prevent the whirling caused by the drag torque of the clutch of the auxiliary drive unit such as the electric motor.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention relates to a drive device for a front and rear wheel drive vehicle, which comprises a main drive means for driving the main drive wheel side, which is one of the front and rear wheels, and a sub drive, which is the other of the front and rear wheels. The auxiliary drive means for driving the wheel side, and the clutch for connecting and disconnecting the drive power transmission between the auxiliary drive means and the auxiliary drive wheel side. When the auxiliary drive wheel side is driven, A drive device for a front-rear wheel drive vehicle of a type in which the auxiliary drive means and the auxiliary drive wheel side are connected so as to be able to transmit a driving force, and the auxiliary drive means drives the auxiliary drive wheel side. It is a thing. There are many types of drive devices for front and rear wheel drive vehicles of this type, and in this embodiment, two types of drive devices shown in FIGS. 1 and 4 are exemplified.

FIG. 1 schematically shows a first four-wheel drive vehicle 10 which is constructed by mounting a first drive device according to the present invention. The first drive device controls a first drive mechanism 10a that drives the front wheel side that is the main drive wheel, a second drive mechanism 10b that drives the rear wheel side that is the auxiliary drive wheel, and a second drive mechanism 10b. The controller 10c is provided.

The first drive mechanism 10a includes an engine 11 which is an internal combustion engine and a generator 12 which is a generator. In the first drive mechanism 10a, the driving force of the engine 11 is the transmission 13a and the reduction gear train 13
b, transmitted to each drive shaft 13d via the front differential 13c,
The front wheels 13e are driven by d. During this time, the engine 11 drives the generator 12 to generate electric power. The generated electric power is stored in the low voltage battery 14. The low-voltage battery 14 is a battery for driving auxiliary equipment, and is, for example, a 12V battery.

The second drive mechanism 10b includes an electric motor 15,
A DC-DC converter 16, a high voltage battery 17, and an electromagnetic clutch 18 are provided. The high-voltage battery 17 is a dedicated battery for driving the electric motor 15, and is, for example, a 36V battery. Electric motor 1
Reference numeral 5 denotes an electric motor 15 capable of selectively switching between electric energy and mechanical energy for output, and a separately excited motor, a DC motor, a brushless motor or the like can be used as appropriate.

In the second drive mechanism 10b, the electric motor 15 is driven by being supplied with electric power, and the driving force of the electric motor 15 passes through the reduction gear train 19a, the electromagnetic clutch 18 and the rear differential 19b, and each drive shaft 19c. The rear wheels 19d are driven by the drive shafts 19c. In addition, the electric motor 15 is
When receiving a driving force from the rear wheel 19d side, it functions as a generator to generate regenerative electric power. The generated regenerative electric power is stored in the high voltage battery 17 via the drive circuit 10c2 which constitutes the control device 10c.

As shown in FIG. 2, the controller 10c includes an accelerator opening sensor S1, a wheel speed sensor S2, a brake sensor S3, a high voltage battery voltage sensor S4, a switch sensor S5 for detecting the state of a WD switch, and an electric motor. It is connected to a motor sensor S6 that detects the rotation state of the motor 15, and is an MPU (microprocessor) 10c1.
And a drive circuit 10c2.

The MPU 10c1 has a CPU and a memory that holds a control program and data for controlling the electric motor 15 and the electromagnetic clutch 18, and outputs detection signals output from the sensors S1 to S6 via an interface. Take in the electric motor 15 and the electromagnetic clutch 18
It determines the operating state of the electric motor 15, the electromagnetic clutch 18, etc. as a command signal and outputs it to the drive circuit 10c2 via the interface. The drive circuit 10c2 controls the drive and power generation of the electric motor 15 based on the command signal from the MPU 10c1, and
ON-OFF control of the electromagnetic clutch 18 is performed. MPU1
The control program of 0c1 is the electromagnetic clutch 18
Holds a control program for preventing whirling due to the drag torque in the.

That is, the control device 10c controls the success or failure of the four-wheel drive state, drives the electric motor 15,
It has a control function of controlling switching and a control function of preventing whirling due to drag torque in the electromagnetic clutch 18.

The control device 10c has the 4WD switch turned on.
The electric motor 15 and the electromagnetic clutch 18
Control to select the operating state of. The control device 10c is
Based on signals from the accelerator opening sensor S1, the wheel speed sensor S2, the brake sensor S3, the high-voltage battery voltage sensor S4, and the switch sensor S5 that detects the state of the WD switch, the state in which the electric motor 15 should operate, the electromagnetic state The state in which the clutch 18 should be operated is determined. The determination result is output to the drive circuit 10c2 as a command signal, and the drive circuit 1c2
0c2 controls the operation of the electric motor 15 and the electromagnetic clutch 18 based on the command signal.

FIG. 3 is a flow chart for executing a control program for controlling the operation of the electric motor 15 and the electromagnetic clutch 18 by the control device 10c. Control device 10
The microcomputer composing c is step 101.
When it is determined that the 4WD switch is in the ON state, in step 102, it is determined that the operating state of the electric motor 15 should be selected. Further, when the microcomputer determines in step 101 that the 4WD switch is in the OFF state, it also turns off the electromagnetic clutch 18 in step 103 and ends the execution of the control program.

The microcomputer executes step 102.
At, the power generation control is determined whether or not the electric motor 15 should select the power generation operation. The determination of the power generation control is performed based on the voltage of the high voltage battery 17, the wheel speed, and the operating state of the brake, and the voltage of the high voltage battery 17 is equal to or less than a predetermined value.
When the wheel speed is equal to or lower than a predetermined value and the brake is in the operating state, it is determined to be power generation control, and the program is executed in step 104.
And the electromagnetic clutch 18 is turned on in step 104.
Then, in step 105, the electric motor 15 is controlled to be in a power generation operable state. As a result, the electric motor 15 is operated by the rear wheel 1
It is driven by the driving force from the 9d side to generate regenerative electric power. The generated regenerative power is used by the drive circuit 1 of the control device 10c.
It is stored in the high-voltage battery 17 via 0c2 and raises the voltage of the high-voltage battery 17 to a predetermined value or more.

The microcomputer executes step 102.
When it is determined that the power generation control is not performed, the program proceeds to step 106, and in step 106, the drive control is determined whether or not the electric motor 15 should select the drive operation. The drive control is determined based on a signal from an accelerator opening sensor, a wheel speed sensor, or the like. If the vehicle is in a low speed state and the accelerator opening is equal to or more than a certain value, it is determined to be drive control, and the program proceeds to step 107. Proceed, step 1
At 07, the electromagnetic clutch 18 is turned on, and at step 108, the electric motor 15 is controlled to a drivable state.
Drive circuit 1 of high voltage battery 17 to control device 10c
Electric power is supplied to the electric motor 15 via 0c2. As a result, the rear wheels 19d are driven by the drive of the electric motor 15 to bring the vehicle into the four-wheel drive traveling state.

When the microcomputer determines in step 106 that the drive control is not performed, the program proceeds to step 109 to turn off the electromagnetic clutch 18, and in step 110, the high voltage battery 17 The electric motor 15 is maintained in a non-driving state without supplying electric power to the electric motor 15.

The microcomputer circulates and executes the above control program based on the flowchart. In this case, when the electromagnetic clutch 18 is disengaged (OFF), control to control torque generation in the electromagnetic clutch 18, which will be described later, is performed.

As described above, in the front and rear wheel drive vehicle 10 equipped with the drive device, the control device 10c can be used to smoothly change the vehicle to the four-wheel drive state when necessary and the rear wheels 19d. The power that is the driving source of
Although the electricity can be stored according to the consumption without any problem, the electricity stored in the high-voltage battery 17 is used as a drive source for driving the electric motor 15 that is the drive means for the rear wheels 19d, and the electric motor 15 is used. The use of a dedicated generator to drive is abolished. The high-voltage battery 17 can be mounted anywhere in a narrow space of the vehicle, and therefore the mountability of the drive device on the vehicle is extremely good.

Further, as the drive source of the electric motor 15, the stored electric power of the high-voltage battery 17 is adopted in place of a dedicated generator for driving the electric motor 15, so that a four-wheel drive vehicle has a two-wheel drive configuration. The design of the vehicle does not need to be changed significantly, and the dedicated design of the four-wheel drive vehicle is unnecessary for the configuration of the four-wheel drive vehicle. Therefore, an increase in cost for constructing a four-wheel drive vehicle can be significantly reduced.

In the drive system, the low-voltage battery 14 for storing the electric power generated by the generator 12 driven by the engine 11 which is the main drive means is selected as the power source for storing the high-voltage battery 17. It is configured to include a DC-DC converter 16 that converts the stored power of the low-voltage battery 14 into a high voltage and stores it in the high-voltage battery 17. The DC-DC converter 16 is
Like the high-voltage battery 17, it can be mounted anywhere in a narrow space of the vehicle, and therefore, good mountability of the drive device in the vehicle can be sufficiently ensured.

In the drive system, the rear wheel 19
An electric motor 15 capable of selectively converting and outputting electric energy and mechanical energy is adopted as the driving means of d, and the electric motor 15 is selected as a power source for storing the high voltage battery 17, and the electric motor 15 The high-voltage battery 17 is also charged with the regenerative electric power generated in Step 1. According to such a configuration, the regenerated electric power of the electric motor 15 can be effectively used, and the energy utilization efficiency can be improved.

Further, in the drive system, the electromagnetic clutch 18 for intermittently transmitting the drive force of the electric motor 15 to the rear wheel 19d side, and the control for controlling each component of the drive system according to the state of the vehicle. The device 10c is provided. As a result, the drive device can be operated so as to accurately form the intended vehicle state, and the efficiency of energy utilization can be further enhanced overall.

The drive device is an extremely effective drive device for constructing the four-wheel drive vehicle of this type as described above. However, the control device 10c constituting the drive device operates when the electromagnetic clutch 18 is OFF. Control function for preventing whirling of an upstream side of the clutch 18 due to drag torque in the electromagnetic clutch 18 (twisting prevention means described later)
Is equipped with. The whirling prevention means is the electric motor 1
5 is a means for driving the electromagnetic clutch 18 to apply a torque in the direction opposite to the drag torque in the electromagnetic clutch 18, and the control device 10c generates a torque in the opposite direction. Based on.

FIG. 4 schematically shows a second four-wheel drive vehicle 20 formed by mounting the second drive device according to the present invention. The drive device includes a first drive mechanism 2 that drives the front wheels.
0a, the second drive mechanism 20b for driving the rear wheel side, and the second
A control device 20c for controlling the drive mechanism 20b is provided.

The first drive mechanism 20a includes an engine 21 which is an internal combustion engine and a generator 22 which is a generator. In the first drive mechanism 20a, the driving force of the engine 21 is the transmission 23a and the reduction gear train 23.
b, transmitted to each drive shaft 23d via the front differential 23c,
The front wheels 23e are driven by d. During this time, the engine 21 drives the generator 22 to generate electric power.

The second drive mechanism 20b includes an electric motor 24 and an electromagnetic clutch 25. Electric motor 24
Drive by being supplied with high voltage power. When the electric motor 24 is driven when the electromagnetic clutch 25 is turned on and engaged, the driving force of the electric motor 24 is reduced by the reduction gear train 2.
6a, the electromagnetic clutch 25, and the rear differential 26b, and is transmitted to each drive shaft 26c,
The rear wheel 26d is driven by each drive shaft 26c.

The generator 22 constituting the first drive mechanism 20a is a generator having a variable generated voltage, and the low voltage battery 28 and the electric motor 24 are connected via the changeover switch 27.
It is configured to be selectively connected to and. The low-voltage battery 28 is used for various accessory parts 2 mounted on the vehicle.
9 to drive 9. The switching operation of the changeover switch 27 is performed via the drive circuit 20c2 of the control device 20c.

As shown in FIG. 5, the control device 20c includes an accelerator opening sensor S1, a wheel speed sensor S2, a brake sensor S3, a low voltage battery voltage sensor S4, a switch sensor S5 for detecting the state of a WD switch, and an electric motor. It is connected to a motor sensor S6 for detecting the rotation state of the motor 24, and is connected to an MPU (microprocessor) 20c1.
And a drive circuit 20c2.

The MPU 20c1 has a CPU, a memory for holding a control program and data for controlling the generator 22, the electromagnetic clutch 25 and the changeover switch 27, and interfaces the detection signals output from the respective sensors S1 to S6. The generator 22, the electric motor 24, the electromagnetic clutch 25, and the changeover switch 27 to be operated, and the generator 2
2. The state in which the electric motor 24, the electromagnetic clutch 25, and the changeover switch 27 should be operated is output as a command signal to the drive circuit 20c2 via the interface. The drive circuit 20c2, based on the command signal from the MPU 20c1,
The switching operation of the changeover switch 27 is controlled, and the generator 2
2 controls the generated power, controls the drive of the electric motor 24, and controls the ON / OFF of the electromagnetic clutch 25. The control program included in the MPU 20c1 holds a control program for preventing the swinging of the upstream side of the clutch 25 due to the drag torque in the electromagnetic clutch 25, as in the first drive device.

That is, the control device 20c controls the success or failure of the four-wheel drive state, the control function of controlling the electric power generated by the generator 22, the control function of controlling the drive of the electric motor 24, and the changeover switch 27. It has a control function of controlling and a control function of preventing whirling due to drag torque in the electromagnetic clutch 25.

The microcomputer constituting the control device 20c determines whether the four-wheel drive state should be selected when the 4WD switch is ON, and when the four-wheel drive state is selected. Determines whether or not the switching state of the changeover switch 27 can be selected, and when it determines that the changeover switch 27 is in the state where the changeover state can be selected, the changeover switch 27 is switched and The electromagnetic clutch 25 is turned on to perform the coupling operation, and the power generation state of the generator 22 is switched from the low voltage side to the high voltage side to connect the generator 22 to the electric motor 24.

As a result, the generator 22 supplies high-voltage electric power to the electric motor 24 to drive the electric motor 24 to form the vehicle in the four-wheel drive state. It should be noted that the determination as to whether or not the four-wheel drive state should be selected by the microcomputer is performed by the accelerator opening sensor S1, the wheel speed sensor S2,
Brake sensor S3, low-voltage battery voltage sensor S
Switch sensor S5 that detects the status of 4, 4WD switch
The four-wheel drive state is formed when the vehicle is starting, accelerating, traveling at a low speed, and the like, when the sufficient amount of electricity stored in the low-voltage battery 28 remains.

The microcomputer constituting the control device 20c executes the above control program based on the flowchart shown in FIG. The microcomputer monitors the remaining amount of the stored power of the low-voltage battery 28 in step 121, advances the program to step 122 when it determines that the remaining amount of the stored power is less than the predetermined value A, and stores the stored power. If it is determined that the remaining amount of electric power is equal to or greater than the predetermined value A, the program proceeds to step 123.

The microcomputer executes step 122.
At, the current consumption of the electric power on the low voltage side is monitored, and if the consumption is less than the predetermined value B, the program proceeds to step 123, and if the consumption is the predetermined value B or more, The program proceeds to step 124. As a result, the connection relationship between the generator 22, the low-voltage battery 28, and the accessory component 29 is maintained, and the generator 22 continues to supply the low-voltage power to the low-voltage battery 28 and the accessory component 29.

The microcomputer executes the step 123.
Then, it is determined whether or not the vehicle should be driven by four wheels. If it is determined that the vehicle is not driven by four wheels, the program proceeds to step 124. As a result, the generator 22, the low-voltage battery 28, and the auxiliary component 2
9, the generator 22 continues to supply low-voltage power to the low-voltage battery 28 and the auxiliary component 29.

The microcomputer executes the step 123.
If it is determined that the vehicle is in the state of four-wheel drive, the program proceeds to step 125. Step 1
25, the electromagnetic clutch 25 is turned on and the changeover switch 2
7 to the electric motor 24 side, and the generator 2
Switch 2 to the high-voltage power generation side. As a result, the electric motor 24 is driven by being supplied with high-voltage electric power from the generator 22 to form the vehicle in the four-wheel drive state.

As described above, in the drive unit, the vehicle can be smoothly formed into the four-wheel drive state when necessary by the operation of the control unit 20c. However, in the drive unit, the engine which is the main drive means is used. As a generator that is driven by 21 to generate electric power, a generator 22 having a variable generated voltage is adopted instead of the conventional generator.
Is configured to be selectively connectable to the low-voltage battery 28 and the auxiliary component 29, which are the conventional low-voltage system accessories, and the high-voltage electric motor 24. Thereby, in the drive device, the generator 22 can drive the electric motor 24 to drive the rear wheel 26d side, and the electric power of the generator 22 can form the vehicle in the four-wheel drive state.

Further, in the drive device, as the generator that is driven by the engine 21 that is the main drive means to generate electric power, a generator 22 having a variable generated voltage is adopted instead of the conventional generator. Since the generator 22 is used as the drive source of the electric motor 24, a dedicated generator for driving the electric motor 24 and other drive means dedicated to the electric motor are unnecessary. Therefore, the mountability of the drive device in the vehicle is extremely good.

Further, since the drive unit is constituted by adopting the generator 22 having the variable generated voltage as the generator for driving the engine 21 which is the main drive unit to generate electric power, the drive unit is concerned. When a four-wheel drive vehicle is configured by adopting the above, it is not necessary to drastically change the configuration of the two-wheel drive vehicle, and the dedicated design of the four-wheel drive vehicle when configuring the four-wheel drive vehicle can be omitted.

Therefore, the increase in cost for constructing a four-wheel drive vehicle can be greatly reduced. Further, since the drive device itself does not require addition of a new expensive component, the cost increase for constructing the four-wheel drive vehicle can be further greatly reduced.

When the drive device is required to bring the vehicle to the four-wheel drive state, for example, power is supplied from the generator 22 to the electric motor 24 for a short time such as when the vehicle starts or runs at a low speed. Therefore, the electric power to the auxiliary component 29 side of the low voltage system is the same as that of the conventional low voltage battery 27.
In this case, the required power to the low-voltage auxiliary component 29 side may be temporarily insufficient.

In this drive device, assuming this case, if the required power to the low voltage system auxiliary component 29 side is temporarily insufficient, the high voltage system electric motor 24 of the generator 22 is supplied. The control device 20c having a control function of canceling the connection is adopted. As a result, the formation of the four-wheel drive state of the vehicle can be temporarily interrupted, and the shortage of required power to the low voltage system auxiliary device side can be compensated.

Therefore, the four-wheel drive vehicles 10 and 2 described above are used.
In each drive device configuring 0, the electromagnetic clutch is disengaged (ON) when switching the four-wheel drive traveling state of the vehicle.
(-OFF) control is performed, but each drive device is provided with a whirling prevention unit that prevents whirling of an electromagnetic clutch upstream of the clutch due to drag torque. The whirling prevention means is a means for imparting rotation to the electric motor in a direction opposite to that due to the drag torque of the clutch, and the control device imparts rotation in the opposite direction to the electric motor. The control program is executed based on the flowchart shown in FIG.

The microcomputer constituting the control device starts the control program and determines the operating state of the electromagnetic clutch in step 131. If the microcomputer determines in step 131 that the electromagnetic clutch is in the disengaged (OFF) state, it advances the program to step 132, and if it determines that the electromagnetic clutch is in the engaged (ON) state. Terminates the execution of the program.

The microcomputer proceeds to step 132.
On the basis of the detection signal of the motor sensor S6, it is determined whether or not the electric motor is in a spiraling state. If it is judged that the electric motor is rotating in the spiraling direction, the program is executed in step 133. If it is determined that the electric motor does not rotate in the swinging direction, execution of the program ends.

The microcomputer executes the step 133.
Then, the rotation speed of the electric motor is determined based on the detection signal from the motor sensor S6, and when it is determined that the rotation speed of the electric motor is less than the set predetermined value C, the execution of the program ends. Further, when the microcomputer determines in step 133 that the rotation speed of the electric motor is equal to or higher than the set predetermined value C, the microcomputer advances the program to step 134, and in step 134, the electric motor is supplied with power from the power source. The electric power in the reverse direction is applied through the drive circuit to control the electric motor so that the rotational speed in the orbiting direction becomes equal to or lower than the set predetermined value C, and the execution of the program ends. As a result, in each drive device that constitutes each four-wheel drive vehicle, the occurrence of whirling of the electric motor on the upstream side of the clutch due to the drag torque in the electromagnetic clutch is prevented.

As described above, the whirling prevention control rotates the electric motor in the direction opposite to the whirling direction to control the rotational speed of the electric motor in the whirling direction to be less than the predetermined value C. Is. In this case, the first shown in FIG.
In the drive device constituting the four-wheel drive vehicle 10, the electric power is supplied to the electric motor 15 from the high voltage battery 17. In the drive device constituting the second four-wheel drive vehicle 20 shown in FIG. 4, the electric power is supplied from the generator 22 via the changeover switch 27 when the electric motor 24 is driven. It is also possible to employ a means for supplying electric power from the low-voltage battery 28 when the surroundings are restricted.

FIG. 8 schematically shows a second drive mechanism 30b which constitutes a drive device having the latter type of swinging control means. The second drive mechanism 30b is the second drive mechanism 20b in the drive device that constitutes the second four-wheel drive vehicle.
Have the same configuration except for the swinging control means. In the second drive device 30b, the generator 3
2 is a generator with a variable generation voltage
Similarly to b, the low-voltage electric power and the high-voltage electric power selectively generated by the generator 32 are selectively supplied to the low-voltage battery 38 and the electric motor 3 via the changeover switch.
4 is configured to be supplied.

In the second drive mechanism 30b, however, the electric power supplied when the electric motor 34 is driven is directly supplied from the generator 32 via the drive circuit of the control device 30c, and in the whirling prevention control. , Control device 30
It is supplied from the low-voltage battery 38 via the drive circuit of c. The control device 30c executes a whirling prevention control program based on the flowchart shown in FIG.

The microcomputer constituting the control device starts the control program and determines in step 141 whether the electromagnetic clutch 35 is in the disengaged (OFF) state.
When the microcomputer determines in step 141 that the electromagnetic clutch 35 is in the engaged state, the microcomputer advances the program to step 142 to supply high voltage electric power from the generator 32 to the electric motor 34 to cause the electric motor 34 to operate. To drive.

The microcomputer executes step 141.
When it is determined that the electromagnetic clutch 35 is in the disengaged state, the program proceeds to step 143, and low-voltage reverse-direction electric power is supplied from the low-voltage battery 38 to the electric motor 34 via the drive circuit. The electric motor 34,
The electromagnetic clutch 35 is rotated in the direction opposite to the whirling caused by the drag torque. As a result, the microcomputer ends the execution of the control program.

The above whirling prevention control is based on the whirling preventing means according to an example of the present invention. In the present invention, as the whirling prevention means, other various means, for example, a known brake mechanism or lock mechanism is interposed between the electric motor and the clutch to appropriately operate the brake mechanism or lock mechanism. It is possible to employ a whirling prevention control means for controlling the rotation.

FIG. 10 shows a second drive device 40b in which a lock mechanism is interposed between an electric motor and a clutch and an operating state of the lock mechanism. The second drive mechanism 40b is a first four-wheel drive vehicle. The second drive mechanism 10b in the drive device constituting 10 has the same configuration except the swinging control means.

In the second drive device 40b, as shown in FIG.
As shown in 0, a lock mechanism 40d is provided on the output side of the electric motor 45. The lock mechanism 40d is composed of an output gear 49e which constitutes the reduction gear train 49a and is provided on the output shaft of the electric motor 45, and a lock means which is provided close to the output gear 49e. The lock means is a plunger 49f. The electromagnetic coil 49g and the return spring 49h are main constituent members.

In the lock mechanism 40d, when the electromagnetic coil 49g is not energized, as shown in FIG. 11 (a), the lock means is in the non-operating state and the plunger 49f is in the retracted state. Is facing. In the lock mechanism 40d, the electromagnetic coil 49
When g is energized, the plunger 49f moves forward and meshes with the teeth of the output gear 49e facing each other to stop the rotation of the electric motor 45, as shown in FIG. As a result, whirling of the electric motor 45 due to the drag torque of the electromagnetic clutch 48 is prevented. The control device executes a whirling prevention control program based on the flowchart shown in FIG.

The microcomputer constituting the control device starts the control program and determines in step 151 whether the electromagnetic clutch 48 is in the disengaged (OFF) state.
When the microcomputer determines in step 151 that the electromagnetic clutch 48 is in the engaged state, the microcomputer advances the program to step 152, unlocks the electric motor 45, and ends the execution of the program.

The microcomputer executes step 151.
When it is determined that the electromagnetic clutch 48 is in the disengaged state, the program proceeds to step 153 to lock the electric motor 45 and prevent the electric motor 45 from swinging due to the drag torque of the electromagnetic clutch 48. . As a result, the microcomputer ends the execution of the control program.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a first four-wheel drive vehicle configured by mounting a first drive device according to the present invention.

FIG. 2 is a schematic configuration diagram of a control device that constitutes the drive device.

FIG. 3 is a flowchart for executing a control program included in the control device.

FIG. 4 is a schematic configuration diagram of a second four-wheel drive vehicle equipped with a second drive device according to the present invention.

FIG. 5 is a schematic configuration diagram of a control device that constitutes the drive device.

FIG. 6 is a flowchart for executing a control program included in the control device.

FIG. 7 is a flowchart for executing a whirling prevention control program included in the control device for each drive device according to the present invention.

FIG. 8 is a schematic configuration diagram showing a second drive mechanism of a drive device according to another example.

FIG. 9 is a flowchart for executing a whirling prevention control program included in the control device of the drive device.

FIG. 10 is a schematic configuration diagram showing a second drive mechanism of a drive device according to still another example.

FIG. 11 is an explanatory diagram (a) showing a non-actuated state of a lock mechanism included in the drive mechanism, and an explanatory diagram (b) showing an actuated state of the lock mechanism.

FIG. 12 is a flowchart for executing a whirling prevention control program included in the control device of the drive device.

[Explanation of symbols]

10, 20 ... Four-wheel drive vehicle, 10a, 20a ... First drive mechanism, 10b, 20b, 30b, 40b ... Second drive mechanism,
10c, 20c, 30c ... Control device 11, 21, ... Engine, 12, 22, 32 ... Generator, 13a, 23
a ... transmission, 13b, 23b ... reduction gear train, 13c, 23c ... front differential, 1
3e, 23e ... front wheel, 14, 28, 38 ... low voltage battery, 15, 24, 34, 45 ... electric motor, 16 ... D
C-DC converter, 17 ... High-voltage battery, 18,
25, 35, 48 ... Electromagnetic clutch, 19a, 26a, 4
9a ... Reduction gear train, 19b, 26b ... Rear differential, 19c, 26c ... Drive shaft, 19d,
26d ... rear wheel, 27 ... changeover switch, 29 ... accessory parts,
40d ... Lock mechanism, 49e ... Output gear, 49f ... Plunger, 49g ... Electromagnetic coil, 49h ... Return spring.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Naoyuki Sakai             1-1 Asahi-cho, Kariya city, Aichi             Machine Co., Ltd. (72) Inventor Hiroshi Takin             1-1 Asahi-cho, Kariya city, Aichi             Machine Co., Ltd. (72) Inventor Akira Kodama             1-1 Asahi-cho, Kariya city, Aichi             Machine Co., Ltd. F term (reference) 3D039 AA02 AA03 AB02 AB27 AC03                 3D043 AA07 AA10 AB01 AB17 EA02                       EA05 EA18 EA42 EB03 EB07                       EB12 EB13 EE18 EF09 EF12                       EF14 EF27

Claims (7)

[Claims] 1. A main drive means for driving one of the front and rear wheels on a main drive wheel side, a sub drive means for driving the other of the front and rear wheels on a sub drive wheel side, the sub drive means and the sub drive wheel. And a clutch for connecting and disconnecting a driving force to and from the driving side, and when driving the auxiliary driving wheel side, the clutch connects the auxiliary driving means and the auxiliary driving wheel side so that the driving force can be transmitted. A drive device for a front-rear wheel drive vehicle of a type in which the auxiliary drive means drives the auxiliary drive wheel side.
A whirling prevention means for preventing whirling of an upstream side portion of the clutch due to drag torque in the clutch when the coupling state in which the driving force can be transmitted between the sub driving means and the sub driving wheel side is cut off by the clutch. A drive device for a front-rear wheel drive vehicle, characterized by being provided. 2. The drive device for a front-rear wheel drive vehicle according to claim 1, wherein the whirling prevention means applies a torque in a direction opposite to a drag torque of the clutch to whirle the auxiliary drive means. A drive device for a front-rear wheel drive vehicle, characterized in that the drive device is a whirling prevention means for reducing the following to a predetermined value or less. 3. The drive device for a front-rear wheel drive vehicle according to claim 1, wherein the whirling prevention means applies a braking force to the sub driving means to make the whirling movement of the sub driving means less than a predetermined value. A drive device for a front and rear wheel drive vehicle, which is a whirling prevention device that reduces 4. The drive device for a front-rear wheel drive vehicle according to claim 1, wherein the whirling prevention means is a brake mechanism or a lock mechanism interposed between the auxiliary drive means and the clutch. A drive device for front and rear wheel drive vehicles. 5. An engine, which is an internal combustion engine that drives one of the front and rear wheels, that is, the main drive wheel side, an electric motor that drives the other of the front and rear wheels, that is, the sub drive wheel side, the electric motor, and the sub drive wheel. A clutch for connecting / disconnecting the driving force to / from the driving side, and when driving the auxiliary driving wheel side, the clutch is used to connect the electric motor and the auxiliary driving wheel side so that the driving force can be transmitted. A drive device for a front-rear wheel drive vehicle of a type in which the auxiliary drive wheel side is driven by the electric motor, the drive device being driven by the engine to generate electric power as a drive source of the electric motor. When the connection state in which the driving force can be transmitted between the generator, the electric motor, and the auxiliary drive wheel side is cut off by the clutch, the dragging torque in the clutch prevents the whirling of the upstream side portion of the clutch. Front and rear, characterized in that it comprises a whirling prevention means, the whirling prevention means being a whirling prevention means for controlling the electric power generated by the generator to generate a regulation force for regulating the rotation of the electric motor. Drive system for wheel drive vehicles. 6. The drive device for a front-rear wheel drive vehicle according to claim 5, wherein the generator is a generator having a variable generated voltage, and when the auxiliary drive wheel is driven, electric power is supplied from the generator to the electric motor. Is supplied, and electric power is supplied to the electric motor from a low-voltage battery that stores the electric power of the generator when preventing whirling, a drive device for a front-rear wheel drive vehicle. 7. An engine that is an internal combustion engine that drives one of the front and rear wheels, that is, the main drive wheel side, an electric motor that drives the other of the front and rear wheels, that is, the sub drive wheel side, the same electric motor, and the sub drive wheel. A clutch for connecting and disconnecting a driving force transmittable connection with the side, and a whirling prevention means for preventing whirling of the upstream side of the clutch due to drag torque in the clutch, and when driving the auxiliary drive wheel side. Is a drive device for a front-rear wheel drive vehicle of a type in which the electric motor and the auxiliary drive wheel side are connected to each other by the clutch so that a driving force can be transmitted, and the electric motor drives the auxiliary drive wheel side. In the drive device, the electric motor is an electric motor capable of selectively switching between mechanical energy and electric energy, the regenerative power of the electric motor is used as a drive source, and the whirling prevention means is Serial drive for front and rear wheel drive vehicle, characterized in that the regenerative power is brought about prevention means for generating a braking force is supplied to the electric motor.