JP2001253256A - Vehicle drive - Google Patents

Abstract

(57) [Problem] To provide a vehicle drive device that can be easily attached even in a narrow space such as under a vehicle floor. An engine drives a front wheel of a vehicle. The electric motor 30 drives the rear wheel 36. The engine 20 generates power by driving the first and second generators 40 and 44. The first generator 20 charges a battery, and the second generator 44 supplies electric power to the electric motor 30. The first and second generators 40 and 44 are installed near the engine in the engine room, and the electric motor is arranged near the differential gear integrated with the speed reduction mechanism located substantially at the center of the rear wheel. .

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a vehicle drive device.

[0002]

2. Description of the Related Art As a conventional vehicle drive device, for example,
As described in JP-A-5-131858, in a hybrid vehicle in which the front wheels are driven by an engine and the rear wheels are driven by an electric motor with a reduction gear, a start acceleration according to a road surface condition is obtained when the vehicle starts. It is known that the electric motor is controlled so as to obtain the acceleration to improve the starting acceleration.

[0003]

However, a conventional drive device using a motor with a speed reducer has a problem that the structure is complicated and large, and it is not suitable for mounting in a narrow space under the floor of a vehicle.

An object of the present invention is to provide a vehicle drive device that can be easily mounted even in a narrow space such as under a vehicle floor.

[0005]

(1) In order to achieve the above object, the present invention provides an engine for driving a front wheel of a vehicle, and a first generator which is driven by the engine and charges a battery. An electric motor for driving rear wheels, and a second generator driven by the engine and supplying electric power to the electric motor,
And the second generator is installed in the vicinity of the engine in the engine room, and the electric motor is arranged in the vicinity of the differential gear integrated with the reduction mechanism located substantially at the center of the rear wheel. It is. According to such a configuration, it is possible to easily attach even a narrow space such as under a vehicle floor.

(2) In the above (1), preferably,
The first generator is arranged at a position higher than the second generator.

(3) In the above (1), preferably,
Control means for controlling the second generator and the electric motor, the control means being provided in a wiring path between the battery and the second generator, and having an empty space in the engine room. It is attached to.

(4) In the above (1), preferably,
The second generator and the electric motor are connected by a two-wire wiring path.

(5) In the above (1), preferably,
Control means for controlling the second generator and the electric motor is provided, and the control means is provided in an ABS control unit or an engine control unit.

(6) In the above (2), preferably,
The second power generator is a hermetic power generator that circulates a cooling medium in the power generator and cools it.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure and operation of a vehicle drive device according to an embodiment of the present invention will be described below with reference to FIGS. First, the overall configuration of a four-wheel drive vehicle using the vehicle drive device according to the present embodiment will be described with reference to FIG. FIG. 1 is a system configuration diagram showing an overall configuration of a four-wheel drive vehicle using a vehicle drive device according to one embodiment of the present invention.

The four-wheel drive vehicle 10 includes an engine 20 and a DC motor 30. The driving force of the engine 20 is
Transmission 22 and first axles 24A, 24B
Are transmitted to the front wheels 26A, 26B via the
A and 26B are driven. The driving force of the DC motor 30 is transmitted to the rear wheels 36A, 36B via the clutch 32, the differential gear 33, and the second axles 34A, 34B, and drives the rear wheels 36A, 36B. When the differential gear 33 and the clutch 32 are connected, the DC motor 3
The torque of 0 is applied to the clutch 32, the differential gear 3
3 to the rear wheel axles 34A and 34B,
A and 36B are driven. When the clutch 32 is disengaged, the DC motor 30 is mechanically disconnected from the rear wheels 36A, 36B, and the rear wheels 36A, 36B do not transmit the driving force to the road surface. The outer dimensions of the DC motor 30 are desirably equal to or less than the outer diameter of the differential gear 33, for example, 200 mm or less. The differential gear 33 has a speed reduction mechanism integrally assembled. The DC motor 30 uses, for example, a DC shunt motor that can easily switch between normal rotation and reverse rotation, or a separately excited DC motor.

In the above description, the front wheels 26A, 26
B is driven by the engine 20 and the rear wheels 36A and 36B are driven by the DC motor 30 as a four-wheel drive vehicle. However, the front wheels may be driven by the DC motor and the rear wheels may be driven by the engine. It is good and is also applicable to vehicles with six or more wheels such as trucks and towing vehicles such as trailers.

In the engine room, an auxiliary generator (ALT1) 40 and an auxiliary battery 42 for performing a normal charging and power generation system are arranged, and the output of the auxiliary generator 40 driven by the engine 20 by a belt is output. Auxiliary battery 4
2 is stored. In the vicinity of the auxiliary generator 40,
A driving high-power generator (ALT2) 44 that is driven by the engine 20 by a belt is provided. The driving high-output generator (ALT2) 44 is connected to the high-output generator 44 by a two-wire wiring path PL. The DC motor 30 is driven by the output of the driving high-power generator 44. The auxiliary generator 40 is a general generator of, for example, about 12 V and 2 kW.
This is a generator that can obtain a higher output than the auxiliary generator 40, and is, for example, a generator of about 36 V and 6 kW.

The output of the engine 20 is controlled by an electronically controlled throttle 52 driven by a command from an engine control unit (ECU) 50. The electronic control throttle 52 is provided with an accelerator opening sensor 54 for detecting the accelerator opening. When an accelerator pedal and a throttle of a mechanical link are used instead of the electronic control throttle, an accelerator opening sensor can be provided on the accelerator pedal. The ECU 50
Controls the transmission 22. The transmission 22 is an automatic transmission, and is automatically controlled so that the gear ratio selected by the select lever 23 is achieved. The position of the select lever 23 is detected by a gear position detection sensor 25.
The transmission 22 may be a manual transmission.

The front wheels 26A and 26B and the rear wheels 36
Brakes 28A, 28 provided on the wheels A, 36B
B, 38A and 38B have anti-lock brakes (AB
S) Anti-lock brake (ABS) actuator 29A, 2 controlled by control unit 55
9B, 39A and 39B are provided. Also, front wheel 2
6A, 26B and rear wheels 36A, 36B have rotation sensors 56A, 56 for detecting rotation speed and rotation direction.
B, 58A and 58B are provided. The ABS control unit 55 includes rotation sensors 56A, 56B, 58
A, 58B, etc., to calculate the friction coefficient μ of the road surface, and to apply the braking force corresponding to the value of the friction coefficient μ to the brake 2.
Actuators 29A, 29B, 39A, 39B are operated so as to be applied to 8A, 28B, 38A, 38B.
Note that the rotation sensors 56A, 56B, 58A, 58B
Although provided for each wheel, it may be arranged on one or both of the front wheel axle and the rear wheel axle.

Drive generator output voltage control circuit (GCU)
Reference numeral 60 denotes wheels 26A, 26B, 36A, 36B detected by the rotation sensors 56A, 56B, 58A, 58B.
The vehicle speed is calculated based on the rotation speed of the motor, and the high-power driving generator 44 and the DC motor 30 are calculated based on the calculated vehicle speed.
Control. The GCU 60 controls a field current supplied to a field winding of the DC motor 30. Details of the control by the GCU 60 will be described later with reference to FIG.

Next, the configuration of the vehicle drive device according to the present embodiment will be described with reference to FIG. FIG. 2 is a block diagram illustrating a configuration of the vehicle drive device according to the embodiment of the present invention, and illustrates an example of a circuit configuration related to power supply and control. The same reference numerals as those in FIG. 1 indicate the same parts.
In the connection between blocks in the drawing, a solid line indicates connection of power supply, and a broken line indicates connection of control.

Drive generator output voltage control circuit (GCU)
60 includes rotation sensors 56A, 56B, 58A, 58B.
26A, 26B, 36A, 36 detected by
Information on the rotation speed and rotation direction of B, information on the accelerator opening detected by the accelerator opening sensor 54, and information on the gear position detected by the gear position detection sensor 25 are input.

The GCU 60, based on these information,
The DC motor 30 is controlled by controlling the output voltage of the high-power generator 44 by outputting a command value of the output voltage to the driving high-power generator (ALT2) 44. Further, the GCU 60 directly controls the DC motor 30 by controlling a field current flowing through the field winding 31 of the DC motor 30, and the high-power generator 44.
Thus, a decrease in response caused by controlling the DC motor 30 is improved.

Drive generator output voltage control circuit (GCU)
Reference numeral 60 denotes an I / O circuit 61, an A / D converter 62, a microprocessor (MPU) 63, an I / O circuit 64,
An H-bridge driver 65 and an H-bridge circuit 66 are provided. The gear position information detected by the gear position detection sensor 25 is transmitted to the MPU 63 via the I / O circuit 61.
It is taken in. In addition, the rotation sensors 56A, 56B, 5
8A, 58B detected by the wheels 26A, 26B,
Information on the rotation speeds and rotation directions of the 36A and 36B and information on the accelerator opening detected by the accelerator opening sensor 54 are taken into the MPU 63 via the A / D converter 62. The MPU 63 includes a CPU and a memory for storing programs and data for controlling the electric motor. The MPU 63 calculates the vehicle speed based on the input information,
4 is supplied from the I / O circuit 64 to the driving high-power generator (ALT2) 44 to control the generated output voltage value.

The input circuit to the separately-excited DC motor 30 is constituted by parallel circuits for the armature winding and the field winding.
The armature winding is directly connected to the generator 44 by a two-phase wiring path PL. On the other hand, the H bridge 66
And a signal for controlling the optimal output voltage of the generator 44 and a signal for controlling the optimal armature current of the motor 30 based on the vehicle speed signal S and the like. The controlled field current is supplied to the field winding of the motor 30 for controlling the output. That is, MPU6
Reference numeral 3 denotes a field flowing through the field winding 31 of the DC motor 30 in the H-bridge circuit 66 via the I / O circuit 64 and the H-bridge driver 65 so that the characteristics of the DC motor 30 conform to required values. Adjust the current. Further, power from a low voltage to a high voltage proportional to the engine speed is supplied to the armature winding of the electric motor 30 from the generator 44 directly via the wiring path PL with optimum efficiency. In the present embodiment, the voltage is set to 50 V or less in consideration of high-voltage electric leakage and heat resistance of the generator 44. On the other hand, 12 V power is supplied to the field winding 31 of the electric motor 30 from the 12 V battery 42 via the H bridge circuit 66. When the vehicle is moving backward, a field driving current is supplied from the H-bridge circuit 66 in a direction opposite to the normal rotation, so that the same backward driving force as when the vehicle is moving forward can be obtained. Further, the MPU 63 generates an on / off signal for the clutch 32 and supplies the signal to the clutch 32 from the I / O circuit 64.

As described above, a parallel circuit is adopted, and
By changing the diameter and the number of turns of the armature winding and the field winding, the input current to the armature winding can be increased and the input current to the field winding can be set small. For example, the armature current is set to about 250 A at maximum and the field current is set to 2 at maximum.
It is set to be about 0A or less.

In the above description, each sensor signal is
Although it is directly input to the driving generator output voltage control circuit 60, the amount of the sensor is stored in another control unit (for example, the ECU 50 or the ABS control unit 5).
The information may be obtained from 5) via an in-vehicle LAN (CAN) bus.

The accessory battery 42 is a 12V battery, and forms a normal charge / discharge system with the accessory generator 40 and various electric loads for the 12V power supply. Field-side power of the DC motor 30 and the driving high-power generator 44 is supplied from the auxiliary generator 40 and the auxiliary battery 42. By providing two power supply systems, control can be performed in two ways: a method of controlling the field current of the driving high-power generator 44 and a method of controlling the field current of the DC motor 30. For example, when the required rotation speed of the electric motor is low and the required torque is high, such as when starting a vehicle,
By setting the output current value of the driving high-output generator 44 to a value that increases, the electric motor outputs low rotation and high torque. In addition, when the required rotation speed of the electric motor is high and the required torque is low when the vehicle is running, it is possible to cope with the situation by setting the output voltage value of the driving high-output generator 44 to a large value. Further, by lowering the field current of the DC motor 30, while improving the responsiveness when the vehicle is running,
The rotation speed of the motor can be increased. Also, when the required torque distribution value is higher for the front wheels 26 than for the rear wheels 36, the field current value of the driving high-power generator 44 is adjusted to make the torque distribution between the front wheels 26 and the rear wheels 36 variable. it can.

The power supply line of the clutch 32 is connected to an auxiliary battery 42. By controlling the on / off operation of the clutch 32 by the MPU 63, the power generation of the driving high-power generator 44 whose power generation constantly changes. When the four-wheel drive function is not required without depending on the force, the mechanical connection between the rear wheels 36A, 36B and the DC motor 30 can be forcibly disconnected. For example, when the vehicle speed reaches 20 km / h, the clutch 32 is turned off, and the drive system for only the front wheels is used, so that the brush abrasion amount of the DC motor 30 can be reduced as compared with a system operating in the entire vehicle speed range. When the clutch 32 is disengaged, the DC motor 3
Since 0 is not used, the driving high-power generator 44 can be switched by a switch, and can be used as a power source for the charging device and other accessories.

The motor 30 is used as a generator at a high speed or on a downhill, and a device for charging or consuming the power generated by the motor 30 is provided in the vehicle to obtain braking force such as regenerative braking and power generation braking. be able to. In this embodiment, since the field current is set to a small value of about 20 A, the field current supply system, that is, the power line is formed on the same substrate as the signal control unit 60 including the microprocessor 63 in the middle. can do. The signal lines entering and leaving the microprocessor 63 can of course be formed on the same substrate as the signal control unit 60. That is, a control device having a drive motor and a drive means for controlling a dedicated generator can reduce the current independently of other devices.
If it is a wiring path between the V-system battery 42 and the input side of the dedicated generator 44, it can be installed alone in an empty space in the engine room, or an engine control unit that controls another engine with a microcomputer, and controls the braking force It can be built into the ABS control unit board that is shared or independent.

Next, the structure of the motor used in the vehicle drive device according to the present embodiment will be described with reference to FIGS. FIG. 3 is a longitudinal sectional view showing a configuration of an electric motor used in a vehicle drive device according to one embodiment of the present invention, and FIG.
FIG. 4 is a transverse sectional view of FIG. 3.

The motor 30 is a DC shunt motor. The armature winding 30A is supplied with power of 50 V or less from the generator 44, and the field winding 30B is supplied with 12V power. The input current to the armature winding is set to be large, and the input current to the field winding is set to be small. Armature winding 30
A is supplied with relatively high voltage and large current power.
The number of turns can be reduced, and the armature core 30C can be downsized, that is, the radius can be reduced. On the other hand, the field winding 3
Since 0B is supplied with lower voltage and lower current power, the number of turns is increased.

As described above, different amounts of power are supplied from the two power supplies to the armature winding 30A and the field winding 30B,
A radius 1 / 2D of the armature core 30C of the shunt motor 30,
In a general electric motor, the thickness L in the radial direction of the field winding 30B has a relationship of L <１ ／ D. However, L is set as long as possible, and is set to a value close to ＤD.

For this reason, since the radius of the armature core 30C is reduced, the radius of the commutator 30D is also reduced, and the length of the brush 30E in the radial direction is sufficiently increased, so that the life of the brush 30E can be extended. . When the space under the vehicle floor is taken into consideration, the outer diameter of the portion of the electric motor 30 in which the brush 30E is stored is set to be equal to the maximum size of the differential gear 3.
By setting the size corresponding to the outer diameter of the brush 3, the brush 3
The length of 0E can be made sufficiently long.

As described above, by supplying different amounts of power from the two power supplies to the armature winding 30A and the field winding 30B, the brush length can be maximized within the above-described relationship of L <1 / 2D. While securing, the outer dimensions can be made equal to or less than the outer dimensions of the differential gear 33, for example, 200 mm or less.

Next, the output characteristics of the generator 44 used in the vehicle drive device according to the present embodiment will be described with reference to FIG. FIG. 5 is an output characteristic diagram of the generator used in the vehicle drive device according to one embodiment of the present invention.

FIG. 5 shows the output characteristics of the generator 44. In other words, it is also an input characteristic diagram for supplying the electric power to the electric motor 30. It can be seen that, in proportion to the engine speed, the output range of the generator has both the terminal voltage and the current expanded parabolically. That is, in the conventional charge start system, no dedicated generator is provided, and therefore, once connected to the load via a 12 V battery, both the terminal voltage and the output current are independent of the engine speed and the power generation efficiency of the generator. Only the control in a limited fixed range can be selected, and the input of the drive motor can be given only in this limited range. On the other hand, in the present embodiment, the drive motor can be controlled within the parabola shown in FIG. 5, and the drive mode to be provided as the four-wheel drive vehicle can be freely controlled.

As described above, according to the present embodiment, the electric motor 30 is controlled independently of the engine 20. That is, the clutch 32 is turned on to drive the rear wheels of the vehicle only when the vehicle is running (when the vehicle speed is zero) and when the vehicle is traveling forward and backward within a predetermined value (for example, 20 km / h) or less. Is higher than 20 km / h, the clutch 32 is turned off and the vehicle runs only with the engine 20. Compared to a system that drives the rear wheels of the vehicle via the propeller shaft from the engine, a transmission mechanism and a propeller shaft from the engine are not required, and the four-wheel drive mechanism is reduced in size and weight. Since the rear wheel side is separated from the front wheel side, it also contributes to improved fuel efficiency. Further, at the time of startup, that is, since the start assist can be obtained from the state where the vehicle speed is zero, the start acceleration is excellent.

Further, according to the present embodiment, by supplying different amounts of power from the two power supplies to the armature winding 30A and the field winding 30B of the electric motor 30, the aforementioned L <1/1 /
By setting the outer dimensions to be equal to or less than the outer dimensions of the differential gear 33 while securing the brush length within the 2D relationship, the space required for mounting under the vehicle floor can be reduced.

Further, according to this embodiment, the input circuit to the shunt motor 30 is constituted by a parallel circuit for the armature winding and the field winding, and the armature winding 30A is connected to the field winding. By supplying power to the magnetic winding 30B from a power supply having a different voltage, the field current can be set to a small value of about 20A. Therefore, the field current supply system, that is, the middle part of the signal line SL can be formed on the same substrate as the signal control unit 60 including the microprocessor 63. The signal lines entering and leaving the microprocessor 63 can of course be formed on the same substrate as the signal control unit 60. Also,
Since the field current is small, the field current supply system of the electric motor 30 and its control circuit can be formed on the same substrate as the ABS control unit 55. In addition, a supply system of the field current of the electric motor 30 and a control circuit therefor are:
It may be formed in the same substrate as the engine control unit 50. Alternatively, they may be formed on the same substrate as the ABS control unit 55 and the engine control unit 50. This makes it possible to reduce the cost of the field current supply system of the shunt motor 30 and its control circuit. On the other hand, the generator 44
It is of course possible to make the device incorporating the drive means for controlling both the motor and the electric motor 30 independent, and to install the device in an empty space in the engine room in the wiring path between the battery and the input side of the second generator. It can also be attached externally to existing control systems, and is extremely versatile.

Next, the mounting state of the two generators 40 and 44 used in the vehicle drive device according to the present embodiment will be described with reference to FIGS. 6 and 7 are explanatory views of the mounting state of two generators used in the vehicle drive device according to one embodiment of the present invention, FIG. 6 is a side view, and FIG. 7 is a front view.

FIG. 6 shows a vehicle equipped with a power steering system used to improve the steerability of wheels, in which an electric power steering system for rotating a drive shaft of the power steering by an electric motor without using hydraulic pressure is also used. The mounting state of the engine room ER of the vehicle viewed from the side of the vehicle is shown. The first generator 40 is
It is connected and driven by the engine 20 and the belt A, and is located at a position higher than the second generator 44. The second generator 44 uses the vicinity where a hydraulic system device such as a hydraulic pump is conventionally installed, and Located in. Since the second generator 44 is located at a lower position in the vicinity of the first generator 40, the belt drive is similarly facilitated, and the engine 20, the first generator 40, and the second
By laying out the generators 44 at staggered positions, the installation space in the engine room can be further reduced, and the mountability can be increased.

Next, as shown in FIG. 7, the generators 40 and 44 mounted on the engine 20 are driven via the belt B. In the figure, two generators 40 and 44 are one belt B
, But a separate power transmission device such as a belt may be used. The generator 40 is generally widely used as a vehicle generator at present, and is cooled by introducing outside air with a cooling fan, and has a ventilation window on a birdcage. On the other hand, the generator 44 is
On the other hand, the generator 44 is located closer to the ground than the generator 40, and the generator 44 is mounted on the road to prevent the road from freezing in the winter, in which sand and dust that the tire rolls up when the vehicle is running, water in rainy weather, and road in winter. It is placed in a place where it is more susceptible to substances that impair the function of the generator, such as sodium chloride and calcium chloride, which promote rust when entering the generator, such as sodium chloride and calcium chloride.

Here, the configuration of the generator 40 used in this embodiment will be described with reference to FIG. FIG. 8 is a longitudinal sectional view of the first generator used in the vehicle drive device according to one embodiment of the present invention.

The generator 40 has a cooling fan, which is relatively commonly mounted on vehicles at present, and has a structure for cooling the generator itself by introducing and discharging outside air from a birdcage-like ventilation window. I have. Generator 40 receives torque from the engine. The generator 40 includes a pulley 40A and a rotor 40B.
And brackets 40D and 40E for holding the stator 40C and mounting it on the engine, and cooling fans 40F and 4C.
0 G or the like. Ventilation windows 40H, 40I are arranged on the brackets 40D, 40E, and the cooling fan 40
By introducing and discharging outside air by the F and 40G, the structure is such that self-heating during power generation is cooled. When the generator 40 is arranged at a position relatively close to the ground and easily exposed to the generator, water, sodium chloride,
Calcium chloride easily penetrates and the corrosion progresses quickly.
In addition, foreign substances such as mud may clog the ventilation windows of 40H and 40I, which significantly lowers the cooling performance. Therefore, as shown in FIG. 7, the generator 40 is relatively high and is mounted at a position distant from the ground.

Next, the configuration of the generator 44 used in this embodiment will be described with reference to FIG. FIG. 9 is a side view of the second generator used in the vehicle drive device according to one embodiment of the present invention.

The generator 44 shown in FIG. 9 has a structure suitable for being arranged at a position relatively close to the ground. The generator 44 holds a rotor and a stator (not shown) of the generator by a bracket without a ventilation window, and is mounted on the engine. In addition, the cooling medium of the engine is received from the cooling medium supply port 44A, and the self-heating during power generation is cooled by appropriately circulating the cooling water in the generator, and then returned to the engine side from the cooling medium discharge port 44B, and attached to the engine. After cooling with a radiator, it is recirculated. When the generator 44 having the configuration shown in FIG. 9 is arranged relatively close to the ground as shown in FIG. 7, since the cooling fan and the ventilation window are not provided, the cooling fan draws in outside air from the ventilation window. It is not necessary to discharge. Therefore, there is no inhalation of substances that promote rust or foreign substances that may cause a failure.Especially, even if the generator is flooded while the vehicle is running, foreign substances such as water will not enter the generator. Almost gone. Also,
The cooling of the generator itself is performed by the medium supplied from the engine side.Therefore, the power generation performance and life are not restricted by the attachment of foreign matter to the birdcage-like ventilation window or the presence or absence of the drip-proof cover, and the environment changes. Change in cooling performance is small,
It is possible to obtain stable power generation and life.

The generator 44, which is substantially sealed, is provided with a hole 44C for breathing and drainage so that dew condensation and moisture permeated from a small gap in a part where components are combined are formed. Although it can be pulled out, compared to a configuration that uses a cooling fan and a birdcage-shaped ventilation window, the area is much smaller, so the amount of water intrusion into the interior of the generator due to flooding, etc. Therefore, corrosion prevention and invasion of foreign matter do not matter.

Further, since the generator does not have a cooling fan, the noise generated by the cooling fan and the interference noise of the cooling wind with the generator components are eliminated from the generator requiring the cooling fan. Therefore, it is possible to suppress noise from the generator, which is a concern when a plurality of generators are mounted.

By using the above-described mounting structure and the generators shown in the figures, a high-power, long-life vehicle generator can be easily mounted on a vehicle without worrying about corrosion resistance. Can be added. In particular, for vehicles in which the electric power steering is adopted and the conventional hydraulic pump for the hydraulic power steering driven by the engine by a belt or the like is eliminated, the generator is located at the position where the hydraulic pump was located. By placing an auxiliary device driven by another belt or the like at the position of the hydraulic pump and locating the generator for the vehicle at the vacant position, the belt system does not change and the engine Since it does not affect the arrangement and shape of the components existing in the vehicle, a vehicle generator can be easily and inexpensively added. Particularly, when a vehicle generator having a larger power generation capacity is added as compared with a conventionally mounted vehicle generator, for example, when a vehicle generator is added as a power source of a vehicle drive motor, a vehicle having a large power generation capacity is used. In order to reduce the size of the generator for the vehicle, a vehicle generator for cooling the self-heating of the vehicle generator by circulating the engine cooling medium in the generator is essential. The mounting method is rational and effective. Further, the noise generated by the generator can be significantly reduced as compared with the case where a plurality of generators having cooling fans are mounted.

[0048]

According to the present invention, a vehicle drive unit can be easily mounted even in a narrow space such as under a vehicle floor.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram showing an overall configuration of a four-wheel drive vehicle using a vehicle drive device according to one embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a vehicle drive device according to one embodiment of the present invention.

FIG. 3 is a longitudinal sectional view showing a configuration of an electric motor used in the vehicle drive device according to one embodiment of the present invention.

FIG. 4 is a cross-sectional view of FIG.

FIG. 5 is an output characteristic diagram of a generator used in the vehicle drive device according to one embodiment of the present invention.

FIG. 6 is an explanatory view of a mounted state of two generators used in the vehicle drive device according to one embodiment of the present invention, and is a side view.

FIG. 7 is an explanatory view of a mounted state of two generators used in the vehicle drive device according to one embodiment of the present invention, and is a front view.

FIG. 8 is a longitudinal sectional view of a first generator used in the vehicle drive device according to one embodiment of the present invention.

FIG. 9 is a side view of a second generator used in the vehicle drive device according to one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... 4 wheel drive vehicle 20 ... Engine 25 ... Gear position detector 26 ... Front wheel 28, 38 ... Brake 30 ... DC motor 31 ... Electric motor field winding 32 ... Clutch 36 ... Rear wheel 40 ... Auxiliary generator 42 ... Auxiliary battery 44 Drive high-power generator 50 Engine control unit 54 Accelerator opening sensor 55 ABS control unit 56, 58 Rotation sensor 60 Drive generator output voltage control circuit

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yuji Maeda 2520 Oita Takaba, Hitachinaka City, Ibaraki Prefecture Inside the Hitachi, Ltd. Automotive Equipment Group (72) Keiichi Masuno Inventor Keiichi Masuno 2520 Oita Takaba, Hitachinaka City, Ibaraki Prefecture Hitachi, Ltd. Automotive Equipment Group (72) Inventor Susumu Tajima, Hitachi, Ibaraki Prefecture, 2520 Oji Takaba Co., Ltd.Hitachi, Ltd. Automotive Equipment Group (72) Inventor Naoya Shimizu, 2520 Address, Hitachinaka, Ibaraki, Japan (72) Inventor Keisuke Nishidate, Hitachi, Ibaraki Pref.

Claims (6)

[Claims] 1. An engine for driving front wheels of a vehicle, a first generator driven by the engine and charging a battery, an electric motor for driving rear wheels, and an electric motor driven by the engine. A second generator for supplying electric power to the engine. The first and second generators are installed near an engine in an engine room, and the motor is decelerated at a substantially central portion of a rear wheel. A vehicle drive device characterized by being arranged near a differential gear in which a mechanism is integrated. 2. The vehicle drive device according to claim 1, wherein the first generator is arranged at a position higher than the second generator. 3. The vehicle drive device according to claim 1, further comprising control means for controlling said second generator and said electric motor, wherein said control means is a wiring path between said battery and said second generator. A vehicle drive device provided inside and mounted on an empty space in an engine room. 4. The vehicle drive device according to claim 1, wherein the second generator and the electric motor are connected by a two-wire wiring path. 5. The vehicle drive device according to claim 1, further comprising control means for controlling the second generator and the electric motor, wherein the control means is provided in an ABS control unit or an engine control unit. Characteristic vehicle drive device. 6. The vehicle drive device according to claim 2, wherein the second generator is a hermetic generator that circulates a cooling medium in the generator and cools it. .