JPH02258425A - Four-wheel drive vehicle - Google Patents

Abstract

PURPOSE:To control the power distribution to front and rear axles and perform continuously variable power distribution by providing front and rear fluid pumps functioning as fluid couplings at the middle between front and rear propeller shafts, and controlling the operations of these pumps. CONSTITUTION:One end sides of front and rear propeller shafts 16 and 18 are connected to the output gear 14 of a power distributor 10 connected to the output shaft 8 of a transmission 6, and the other end sides of the propeller shafts 16 and 18 are connected to driving axles 24 and 26 of front wheels 28 and rear wheels 30 via final reduction gears 20 and 22. In this four-wheel drive vehicle 2, front and rear fluid pumps 32 and 34 functioning as fluid couplings are provided at the middle between the front and rear propeller shafts 16 and 18. The valve body 64 of a control valve mechanism 60 is moved and controlled by a drive section 68, front and rear fluid passages 52 and 58 are opened or closed, thereby the operations of the fluid pumps 32 and 34 are controlled, and the power distribution to the front and rear driving axles 24 and 26 is controlled.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to four-wheel drive vehicles, and particularly to four-wheel drive vehicles that can perform optimal torque distribution according to all driving conditions and improve driving performance and stability. Regarding 4-wheel drive vehicles that can

[Conventional technology]

Recently, in order to improve the driving performance and stability of vehicles in all driving conditions, including driving on rough roads and uneven terrain, as well as driving on normal roads, the driving force of the internal combustion engine is being transferred to the front wheel drive axle and the rear wheel drive. Various types of four-wheel drive vehicles have appeared in which power is transmitted to an axle to drive the front and rear wheels.

As such a four-wheel drive vehicle, for example, the Utility Model 58-2
There is one disclosed in Japanese Patent No. 5730. What is disclosed in this publication, for example, transmits the driving force of an internal combustion engine to the main driving wheels, which are the front wheels, by a mechanical transmission mechanism, and transmits the driving force of the internal combustion engine to the auxiliary driving wheels, which are the rear wheels, by a hydraulic transmission mechanism. In a four-wheel drive vehicle, when the mechanical transmission mechanism drives the main drive wheels at low speeds, the hydraulic transmission mechanism is allowed to drive the auxiliary drive wheels, while the mechanical transmission mechanism allows the main drive wheels to be driven at high speeds. In the case of driving, the drive of the auxiliary drive wheels by the hydraulic transmission mechanism is stopped and the wheels are idled.

As described above, there are devices disclosed in Japanese Utility Model Publication No. 56-49786 and Japanese Patent Publication No. 63-33580 that transmit the driving force of an internal combustion engine via fluid to drive wheels. What is disclosed in Japanese Utility Model Publication No. 56-49786 is that in a vehicle that runs with a power source consisting of a variable displacement pump and a motor, when the control lever is operated to the running position at the time of starting, the fluid supply is stopped. This prevents the risk of the vehicle starting to run immediately if the starting operation is performed while the vehicle is in the running position.

In addition, the one disclosed in Japanese Patent Publication No. 63-33580 is
In vehicles equipped with a torque converter and a function to prevent creep caused by the torque converter, by controlling the fluid in the torque converter according to the temperature, it is possible to prevent the vehicle from suddenly starting when the creep prevention function is released at low temperatures. This is to prevent this.

[Problem that the invention seeks to solve]

By the way, as shown in FIGS. 5 and 6, the input gear 112 of a power distributor 110 is connected to the output shaft 108 of the transmission 106 of the internal combustion engine 104 in the four-wheel drive vehicle 102, and the output of the power distributor 110 is connected to the output shaft 108 of the transmission 106 of the internal combustion engine 104. One end side of a front propulsion shaft 116 and a rear propulsion shaft 118 are connected to the gear 114, respectively, and a front terminal reduction gear 120 and a rear terminal reduction gear 122 are connected to the other end sides of the front propulsion shaft 116 and rear propulsion shaft 118, respectively. The front wheel drive axle 124 and the rear wheel drive axle 126 are connected to the front wheel drive axle 124 and the rear wheel drive axle 126 via
There is also one with a rear wheel 130 attached. This four-wheel drive vehicle 102 has a central differential 132 interposed between the output gear 114 of the power distributor 110 and the front propulsion shaft 116 and rear propulsion shaft 118.

As a result, this four-wheel drive vehicle 102 has an internal combustion engine 104.
The driving force of the front propulsion shaft 116 and rear propulsion shaft! 18 to the front wheel drive axle 124 and the rear wheel drive axle 126 to drive the front wheels 128 and the rear wheels 130. At this time, the torque of the driving force of the internal combustion engine 104 that is transmitted to the front wheel drive axle 124 and the rear wheel drive axle 126 is distributed at a constant ratio by the central differential 132.

For example, front wheel drive axle 124 and rear wheel drive axle 12
6, each is distributed at a fixed ratio such as so:so or 65:35 respectively.

In this way, the four-wheel drive vehicle 102 that distributes the torque of the driving force at a certain fixed ratio uses the central differential 1
In place of 32, there are models equipped with an idler, star gear mechanism, etc.

However, depending on the four-wheel drive vehicle 102 that distributes torque at a fixed ratio as described above, there is a problem that the torque distribution required depending on the driving state cannot be satisfied. Therefore, as shown in FIGS. 7 and 8, one end of the front propulsion shaft 116 is connected to the output gear 114 of the power distributor 110, and the input gear 112 of the power distributor 110 is connected to the output gear 114 of the power distributor 110 via a multi-plate clutch 134. One end of the rear propulsion shaft 118 is connected to the other end of the front propulsion shaft 116 and the rear propulsion shaft 118, and the front final reduction gear 120 and the rear final reduction gear 122 are connected to the front wheel drive axle 124 and the rear wheels. A drive axle 126 is connected to the front wheel drive axle 124 and the rear wheel drive axle 126.
There is a four-wheel drive vehicle 102 equipped with front wheels 128 and rear wheels 130.

Thereby, the torque of the driving force of the internal combustion engine 104 is transmitted to the front wheel drive axle 124 and the rear wheel drive axle 126 via the front propulsion shaft 116 and the rear propulsion shaft 118 to drive the front wheels 128 and the rear wheels 130. is multi-plate clutch 1
34 to a ratio of 100:0 to 50:5 for the front wheel drive axle 128 and the rear wheel drive axle 130, respectively.
It is possible to vary the distribution up to a ratio of 0.

However, the torque distribution required for a four-wheel drive vehicle varies depending on driving conditions, road surface conditions, and the like.

For example, during high-speed cruising, the front wheel drive axle 124 and the rear wheel drive axle 126 each have a diameter of 60 to 70,740.
Torque is distributed at a ratio of 30%, and when making sharp turns, the torque is distributed at a ratio of 10% to 100% respectively.
Torque is distributed at a ratio of 30:90 to 70, when accelerating on a split μ road, torque is distributed at a ratio of 40:60, at low speeds with large steering angles, torque is distributed at a ratio of 0:100, and when braking, torque is distributed at a ratio of 0:100. too:o or 0:1 respectively
It is necessary to distribute torque at a ratio of 0:0 or 0:0. The torque distribution during braking is determined by matching with the anti-skid brake system.

As described above, the problem with the variously changing required torque distribution is that the conventional central differential or multi-plate clutch notch cannot satisfy the required torque distribution depending on the driving condition. Therefore, it is not possible to perform optimal torque distribution according to all driving conditions, and there is a problem in that driving performance and stability cannot be sufficiently improved. In addition, multi-disc clutches have a complicated structure, so
This had the disadvantage of increasing costs.

[Purpose of the Invention] Therefore, the purpose of the present invention is to realize a four-wheel drive vehicle that can perform optimal torque distribution according to all driving conditions and improve driving performance and stability. .

[Means for solving problems]

To achieve this object, the present invention transmits the driving force of an internal combustion engine to a front wheel drive axle and a rear wheel drive axle through a front propulsion shaft and a rear propulsion shaft, respectively, to drive the front wheels and the rear wheels. In a wheel drive vehicle, a front fluid pump and a rear fluid pump functioning as fluid couplings are interposed between the front propulsion shaft and the rear propulsion shaft, and the driving force of the internal combustion engine is transferred to the front propulsion shaft and the rear propulsion shaft. The present invention is characterized in that a control means is provided for controlling the operation of the front fluid pump and the rear fluid pump so as to distribute the transmission as desired to the front wheel drive axle and the rear wheel drive axle, respectively.

[Effect]

According to the configuration of the present invention, the control means causes the driving force of the internal combustion engine to be distributed and transmitted to the front wheel drive axle and the rear wheel drive axle as desired via the front propulsion shaft and the rear propulsion shaft, respectively. By controlling the operation of the fluid pump and the rear fluid pump, which function as fluid couplings that are interposed between the front and rear propulsion shafts, the front and rear fluid pumps are connected to the front and rear drive axles. The driving force of the internal combustion engine transmitted to the engine can be varied steplessly and distributed as desired.

〔Example〕

Next, embodiments of the present invention will be described in detail based on the drawings.

1 to 4 show embodiments of this invention.

In the figure, 2 is a four-wheel drive vehicle, 4 is an internal combustion engine, 6 is a transmission, 8 is an output shaft, and 10 is a power distributor. An internal combustion engine 4 mounted on a four-wheel drive vehicle 2 connects an input gear 12 of a power distributor 10 to an output shaft 8 of a transmission 6. The output gear 14 of the power distributor 10 is connected to one end side of a front propulsion shaft 16 and a rear propulsion shaft 18, respectively, and a front section is connected to the other end side of the front propulsion shaft 16 and rear propulsion shaft 18, respectively. A front wheel drive axle 24 and a rear wheel drive axle 26 are connected via a final reduction gear 20 and a rear final reduction gear 22 . A front wheel 28 and a rear wheel 30 are attached to the front wheel drive axle 24 and the rear wheel drive axle 26. As a result, this 4
The wheel drive vehicle 2 transmits the driving force of the internal combustion engine 4 to the front wheel drive axle 24 and the rear wheel drive axle 26 via the front propulsion shaft 16 and the rear propulsion shaft 18, and drives the front wheels 28 and the rear wheels 30. are doing.

In such a four-wheel drive vehicle 2, the front propulsion shaft 16
A front fluid pump 32 and a rear fluid pump 34, which function as fluid couplings, are interposed in the middle of the rear propulsion shaft 18.

The front fluid pump 32 includes a front housing part 36 and a front rotor part 38, and the front housing part 36 and the front rotor part 38 define a front pump chamber 40. The front fluid pump 32 includes a front housing portion 36
The front propulsion shaft portion 16 on the output gear 14 side of the power distributor 10
a, and the front rotor portion 38 is provided so as to be connected to the front propulsion shaft portion 16b on the front final reduction gear 20 side.

Further, the rear fluid pump 34 includes a rear housing part 42 and a rear rotor part 44, and the rear housing part 42 and the rear rotor part 44 define a rear pump chamber 46. The rear fluid pump 34 has a rear housing portion 42 connected to the rear propulsion shaft portion 18a of the output gears 14 of the power distributor 10, and a rear rotor portion 44.
is connected to the rear propulsion shaft portion 18b on the rear final reduction gear 20 side.

The front fluid pump 32 is provided with a discharge section 48 and a suction section 50 of the front pump chamber 40 communicating with each other through a front fluid passage 52 . The rear fluid pump 34 also connects the discharge section 54 and suction section 56 of the rear pump chamber 46 to the rear fluid passage 58.
This is established by contacting the following. The front fluid passage 52 and the rear fluid passage 58 have a control valve mechanism 6 as a control means in the middle of the passage.
It is set up by contacting 0.

This control valve mechanism 60 has a main body 62 and a valve body 64 that is moved within the main body 62, and a drive section 68 that is driven and controlled by a control section 66 according to the running state of the four-wheel drive vehicle 2. The valve body 64 is moved by the valve body 64 to open and close the front fluid passage 52 and the rear fluid passage 58, thereby controlling the operation of the front fluid pump 32 and the rear fluid pump 34.

Thereby, the control valve mechanism 60 distributes and transmits the driving force of the internal combustion engine 4 to the front wheel drive axle 24 and the rear wheel drive axle 26 via the front propulsion shaft 16 and the rear propulsion shaft 18, respectively. Therefore, the operation of the front fluid pump 32 and the rear fluid pump 34 is controlled.

Next, the action will be explained.

The four-wheel drive vehicle 2 transfers the driving force of the internal combustion engine 4 from the transmission 6 to the front propulsion shaft 16 and the rear propulsion shaft I8 through the power distribution device 10.
through the front wheel drive axle 24 and the rear wheel drive axle 2, respectively.
6 and drives the front wheels 28 and rear wheels 30 to drive the vehicle.

Is it controlled according to the driving condition of this 4-wheel drive vehicle 2? 111 part 66
The front fluid pump 32 and the rear fluid pump 34 are moved by moving the valve body 64 in the main body 62 of the control valve mechanism 60 to open and close the front fluid passage 52 and the rear fluid passage 58.
It controls the operation of the engine and distributes the torque of the driving force.

That is, when the valve body 64 in the main body 62 of the control valve mechanism 60 is moved to the central position shown in FIG. and the circulation of fluid discharged from the rear pump chamber 46. As a result, the front fluid pump 32 transmits driving force by controlling the operation of the front housing part 36 and the l'ii1 rotor part 38 to rotate together, and the rear fluid pump 34 transmits driving force to the rear part. The operation of the housing section 42 and rear rotor section 44 is controlled so that they rotate together, thereby transmitting driving force.

Therefore, the driving force transmitted from the power distributor 10 to the front propulsion shaft section 16a and the rear propulsion shaft section 18a, respectively, is transmitted to the front propulsion shaft section 1.6 through the front fluid pump 32 and the rear fluid pump 34. b and the rear III advance shaft portion 18b, the torque is transmitted to the front wheel drive axle 24 and the rear wheel drive axle 26 with a ratio of so:so, respectively, and the front wheels 28 and the rear wheels 30 are drive

When the valve body 64 in the main body 62 of the control valve mechanism 60 is moved to the left end position shown in FIG. 3, the front fluid passage 52 is closed and the rear fluid passage 58 is opened, and the front Circulation of fluid discharged from the pump chamber 40 is prevented, while circulation of fluid discharged from the rear pump chamber 46 is allowed.

Thereby, the front fluid pump 32 is connected to the front housing part 3.
The rear fluid pump 34 rotates the rear housing part 42 and the rear rotor part 44 separately, and transmits driving force by controlling the operation of the rotor part 6 and the front rotor part 38 as one body. Control the operation to rotate i'I
The transmission of driving force is cut off by this.

Therefore, the driving force transmitted from the power distributor 10 to the front propulsion shaft section 16a and the rear propulsion shaft section 18a is transmitted to the front propulsion shaft section 16b via the front fluid pump 32, and the rear fluid pump 3.1 through the rear propulsion shaft section 18b
Since the signal is not transmitted to the front wheel drive axle 24 and the rear wheel drive J axle 26 at a ratio of 100:0, the front wheel 28 is driven.

Furthermore, the valve body 64 in the main body 62 of the control valve mechanism 60
If it has been moved to the right end position shown in the figure, open the front fluid passage 52 and close the rear fluid passage 5,
The fluid discharged from the front pump chamber 40 is allowed to circulate and the fluid discharged from the rear pump chamber 46 is prevented from circulating.

Thereby, the front fluid pump 32 is connected to the front housing part 3.
6 and the front rotor section 38 are controlled to rotate separately, thereby cutting off the transmission of driving force, and the rear fluid pump 34 rotates the rear housing section 42 and the rear rotor section 44 as one body. The driving force is transmitted by controlling the operation so that it rotates.

Therefore, the driving force transmitted from the power distributor 10 to the front propulsion shaft section 16a and the rear propulsion shaft section 18a is not transmitted to the front propulsion shaft section 16b via the front fluid pump 32, and the driving force is not transmitted to the front propulsion shaft section 16b via the front fluid pump 32. via the rear propulsion shaft section 18b
As a result, the power is transmitted to the front wheel drive axle 24 and the rear wheel drive axle 26 at a ratio of 0:100, respectively, and drives the rear wheels 30.

Furthermore, the valve body 64 in the main body 62 of the control valve mechanism 60 is located at the center position shown in FIG. 2, at the left end position shown in FIG.
By being moved to an intermediate position between the right end position shown in the figure, the front fluid communication passage 52 and the rear fluid passage 58 are relatively opened and closed, and the fluid is discharged from the front pump chamber 40 and the rear pump chamber 46. Circulation is allowed by creating a relative difference in the amount of fluid to be circulated. Thereby, the front fluid pump 32 transmits driving force by controlling the operation so that the front housing part 36 and the front rotor part 38 rotate together, and the rear fluid pump 34 transmits driving force to the rear housing part 38. 42 and the rear rotor part 44 are controlled to rotate together to transmit driving force, but at this time, the front fluid pump 32 and the rear fluid pump 34 each have a relatively small amount of fluid circulation. By having a difference between the two, a difference occurs in the driving force to be transmitted.

Therefore, the driving force transmitted from the power distribution m10 to the front propulsion shaft parts 1, 62 and the rear propulsion shaft part 18a is transmitted to the front propulsion shaft part 16b and the rear part via the front fluid pump 32 and the rear fluid pump 34. By being transmitted to the propulsion shaft portion 18b with a difference, the torque is transmitted to the front wheel drive axle 24 and the rear wheel drive axle 26 with a desired ratio of torque distribution, respectively.
The front wheels 28 and rear wheels 30 are driven.

In this case, by moving and positioning the valve body 64 in the main body 62 of the control valve mechanism 60 so that the opening/closing ratio of the front fluid passage 52 and the rear fluid passage 58 gradually changes,
Torque distribution can be changed steplessly between 1oo:o and O;1.00 to achieve desired distribution.

Therefore, it is possible to perform optimal torque distribution according to all driving conditions, and it is possible to improve driving performance and stability. Furthermore, by using a fluid pump that has a proven track record, operation is reliable and stable performance can be ensured.

〔Effect of the invention〕

In this manner, according to the present invention, the control means controls the internal jP! In order to distribute and transmit the driving force of the engine to the front wheel drive axle and the rear wheel drive axle through the front propulsion shaft and the rear propulsion shaft, respectively, as desired, the drive shaft is interposed between the front propulsion shaft and the rear propulsion shaft. By controlling the operation of the front fluid pump and the rear fluid pump, which function as fluid couplings, the front fluid pump and the rear fluid pump continuously transmit the driving power of the internal combustion engine to the front wheel drive axle and the rear wheel drive axle. The amount can be changed and distributed as desired.

Therefore, it is possible to perform optimal torque distribution according to all driving conditions, and it is possible to improve driving performance and stability. Furthermore, by using a fluid pump with a proven track record, operation is reliable and stable performance can be ensured.

[Brief explanation of drawings]

1 to 4 show an embodiment of the present invention, in which FIG. 1 is a schematic plan view of a four-wheel drive vehicle, and FIGS. 2 to 4 are illustrations of the operation of a front fluid pump and a rear fluid pump, respectively. Figures 5 to 8 show conventional examples, Figure 5 is a schematic plan view of a four-wheel drive vehicle equipped with a central differential, Figure 6 is an explanatory diagram of the operation of the central differential, and Figure 7 is a multi-disc clutch. FIG. 8 is a schematic plan view of a four-wheel drive vehicle equipped with a four-wheel drive vehicle, and FIG. 8 is an explanatory diagram of the operation of the multi-disc clutch. In the figure, 2 is a four-wheel drive vehicle, 4 is an internal combustion engine, 6 is a transmission, 8 is an output shaft, 10 is a power distribution device, 16 is a front propulsion shaft, 18 is a rear propulsion shaft, and 20 is a front final reduction gear. 22 is a rear final reduction gear, 24 is a front wheel drive axle, 26 is a rear wheel drive axle, 28 is a front wheel, 30 is a rear wheel, 32 is a front fluid pump, 34 is a rear fluid pump, 52 is a front fluid passageway, 58
6 is a rear fluid passage; 60 is a control valve mechanism; 66 is a control section;
8 is a driving section. Patent applicant: Suzuki Motor Co., Ltd. Agent, Patent attorney Yoshimi Nishigo Figure 3 Figure 4 Figure 5 50 (Former J: 50

Claims (1)

[Claims] 1. In a four-wheel drive vehicle in which the driving force of an internal combustion engine is transmitted to a front wheel drive axle and a rear wheel drive axle through a front propulsion shaft and a rear propulsion shaft, respectively, to drive the front wheels and rear wheels, the front propulsion A front fluid pump and a rear fluid pump functioning as fluid couplings are interposed between the shaft and the rear propulsion shaft, and the driving force of the internal combustion engine is transmitted to the front wheel drive axle and the rear propulsion shaft, respectively, through the front and rear propulsion shafts. 4. A control means is provided for controlling the operation of the front fluid pump and the rear fluid pump so as to distribute the transmission to the rear wheel drive axle in a desired manner.
wheel drive car.