JPS63247123A - Transfer structure for four-wheel drive vehicle - Google Patents

Abstract

PURPOSE:To make transfer structure for 4-wheel drive vehicle compact by arranging a one-way clutch which transmits power for driving one wheel to the other wheel when rotation of the other wheel exceeds over that of one wheel by more than predetermined value onto a shaft arranged in parallel with the shaft at the side where a viscosity clutch is arranged. CONSTITUTION:Power of an engine 1 is transmitted to a transmission 2 where the speed thereof is changed, then it is transmitted through a rear wheel drive shaft 4 and a rear wheel differential 5 to a rear wheel shaft 6. Here, first gear 8 and second gear 9 rotatable with respect to an output shaft 3 are arranged on the output shaft 3 of the transmission 2, while a viscosity clutch 10 is ar ranged between the second gear 9 and the output shaft 3. Rotation of the second gear 9 is made transmittable to a front wheel drive shaft 11 through a gear 12, and a gear 14 engagable with the first gear 8 is arranged on a shaft 13 coaxial with the shaft 11. A one-way clutch 15 which transmits power for driv ing a rear wheel 7 to a front wheel 16 when rotation of the front wheel 16 drops below that of the rear wheel 7 by more than a predetermined value is arranged between the gear 12 and the shaft 13.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a transfer structure for a four-wheel drive vehicle equipped with a viscous clutch and a one-way clutch as a power transmission mechanism.

(Prior art) In general, the drive system for four-wheel drive vehicles is to directly drive the front wheels under normal driving conditions, and drive the rear wheels with a viscous clutch that can tolerate a slight difference in rotation. There is a system in which front wheel drive power is transmitted to the rear wheels via a one-way clutch when the rear wheels rotate more than a predetermined range than the front wheels. (For example, JP-A-59-17
(Refer to Publication No. 9425) However, in the conventional type, the viscous clutch and the one-way clutch are provided on the same axis, so if this shaft is provided in the front-rear direction of the vehicle, for example, in an FR heavy vehicle, As shown in Fig. 2, in the so-called mid-ship type where the viscous clutch is placed at the bottom of the vehicle floor, making the floor space narrower, and the engine is placed in the center of the vehicle, the above-mentioned shaft is If the shaft was placed in the front-rear direction, the propeller shaft on the rear wheel side would become shorter and the bending angle of the propeller shaft would become larger.In addition, if the above-mentioned shaft was placed in the width direction of the vehicle, Since the viscous clutch provided on the shaft protrudes in the vehicle width direction, the layout of other parts disposed in the engine compartment becomes difficult.

(Object of the invention) The present invention was made to solve the above problems, and
The purpose of the present invention is to provide a transfer structure for a four-wheel drive vehicle that has a compact configuration of a viscous clutch and a one-way clutch.

(Structure of the Invention) In order to achieve the above object, the present invention receives the output of a transmission, one of the front and rear wheels is directly driven, and the other is driven via a viscous clutch that allows a slight rotation difference. In addition, in a four-wheel drive vehicle in which the power for driving one wheel is transmitted to the other wheel via the one-way clutch when the other wheel rotates at a lower rotation than one wheel by more than a predetermined value, the one-way clutch described above is used. is provided on a shaft parallel to the shaft on which the viscous clutch is provided.

With the above configuration, the present invention constitutes a viscous clutch and a one-way clutch in a compact manner, which will be explained below using the drawings.〇(Example) Fig. 1 shows an example of the present invention. It is a diagram.

In the figure, 1 is the prime mover of the vehicle, 2 is the transmission, and 3 is the output shaft of the transmission.The driving force of the shaft 3 is transmitted to the rear wheel shaft 6 via the rear wheel drive shaft 4 and the rear wheel differential device 5. The rear wheels 7, which are the wheels of the vehicle, are driven.

Further, the output shaft 3 of the transmission 2 is provided with a first gear 8 and a second gear 9 which is smaller than the gear 8 and is rotatable with respect to the output shaft 3.
A viscous clutch 1° is placed between the two. Reference numeral 11 denotes a front wheel drive shaft, and this shaft 11 is provided with a gear 12 that meshes with the gear 9. A shaft 13 coaxial with the front wheel drive shaft 11 has a
A gear 14 that meshes with the first ξ gear 8 is provided. And gear 12
A one-way clutch 15 is provided between the shaft 13 and the shaft 13 . Note that the gear ratio of gear 8.14 is set larger than the gear ratio of gear 9.12.Next, the operation of the transfer according to this embodiment will be explained.

In the normal running state of the vehicle, one wheel, the rear wheel 7, is directly driven by the driving force of the output shaft 3 of the transmission, and the other wheel, the front wheel 16, is driven by the viscous clutch 10, the second gear 9, the gear 12, and the front wheel. It is driven via a drive shaft 11 or the like. However, when the front wheel 16 rotates lower than the predetermined rotation rate than the rear wheel 7 due to a phenomenon such as slipping of the rear wheel 7, the front wheel 16 is driven via the gear 8.14, the one-way clutch 15, etc. .

By the way, in this example, in addition to the above-mentioned
The one-way clutch 15 is provided between the front wheel drive shaft 11 and the shaft 13, which are arranged parallel to the transmission output shaft 3 on which the viscous clutch 10 is provided. That is, as is clear from FIG. 2, in the past, the one-way clutch 15 and the viscous clutch 1o were provided on the same axis, so the structure became long in the longitudinal direction of the vehicle, but in this embodiment, , gear A in Fig. 2
By focusing on the dead space C between %B and arranging the viscous clutch 1o in this space C, the space C is effectively utilized and the configuration is made compact.

With the above configuration, this embodiment solves the conventional problem of narrowing the floor space.

Although not shown, if a configuration in which a viscous clutch and a one-way clutch are provided on parallel shafts is applied to a midship type vehicle, the above configuration will improve the longitudinal direction of the vehicle compared to the conventional one. Since the length on the right is shortened, the bending angle of the propeller shaft on the rear wheel side can be made smaller accordingly. Furthermore, conventional FF, in which a viscous clutch and a one-way clutch are arranged in the width direction of the vehicle,
If the above configuration is applied to a car, the length in the vehicle width direction can be shortened, so the layout of other parts arranged in the engine room becomes easier.In addition, the gear train 8.14 and Even if you replace 9 and 12 with chain drive system,
The effects of this embodiment can be obtained.

(Effects of the present invention) As is clear from the above explanation, the present invention provides a one-way clutch on a shaft arranged parallel to the shaft on which the viscous clutch is provided, thereby making the overall configuration compact. This solves the various layout difficulties caused by the conventional arrangement of a viscous clutch and a one-way clutch on the same axis.

[Brief explanation of the drawing]

FIG. 1 is a diagram explaining a transfer structure of a four-wheel drive vehicle showing an embodiment of the present invention, and FIG. 2 is a diagram explaining a transfer structure of a conventional four-wheel drive vehicle. ...Transmission, 3...Output 41d1.7...Rear wheel, 10...Viscous clutch, 11...Front wheel drive shaft, t3...・
...Shaft, 15...One-way clutch, 16.
...Front wheel = 159-

Claims (1)

[Claims] In response to the output of the transmission, one of the front and rear wheels is directly driven, and the other is driven via a viscous clutch that allows for a slight difference in rotation. In a four-wheel drive vehicle in which the power driving one wheel is transmitted to the other wheel via a one-way clutch when the rotation becomes lower than a predetermined value, the one-way clutch is provided with the viscous clutch. A transfer structure for a four-wheel drive vehicle characterized by being provided on a shaft arranged parallel to the shaft.