JPH0530510Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a four-wheel drive vehicle.

[Prior art] Conventionally, in a four-wheel drive vehicle equipped with two power transmission systems that distribute and transmit power from the engine to the front wheels and the rear wheels, a differential is allowed between the rear wheel drive system and the front wheel drive system. As a known example equipped with a differential limiting mechanism, for example, the one described in Japanese Utility Model Application Laid-open No. 59-188731 is known.

That is, since the propeller shaft of the rear wheel drive system equipped with the differential limiting mechanism is long, it is divided into, for example, an input propeller shaft 101 and an output propeller shaft 103 as shown in FIG. 3, and each shaft 101, 103 is rotatably supported via a center bearing member 105 fixed to the vehicle body for the purpose of suppressing the occurrence of eccentricity due to insufficient rigidity or the like.

On the other hand, the output side propeller shaft 103 connects the left and right rear wheels 10 via a differential 107.
It is conductively connected to 9. Furthermore, a differential limiting mechanism 111 is provided upstream of the differential 107. The differential limiting mechanism 111 includes a plurality of rotary plates facing each other that are rotatable relative to each other in a sealed chamber in which a viscous fluid is sealed.
Torque is now transmitted to the 7 side. As a result, for example, when a differential occurs between the drive system and the rear wheel drive system when turning, the differential limiting mechanism 111 works to absorb the differential, thereby enabling stable turning. The structure is as follows.

[Problems to be Solved by the Invention] In a conventional four-wheel drive vehicle equipped with such a differential limiting mechanism, one end of the differential limiting mechanism 111 is connected to the output side propeller shaft 103, and the other end is connected to the differential. 107, so when the rotation speed of the differential limiting mechanism 111 increases, it rotates eccentrically, causing noise, rattling, etc., and reducing the durability of the bearings, etc. , high-speed running became unstable, and sufficient machining accuracy and assembly system were required.

For this purpose, for example, a means of supporting the differential limiting mechanism main body on the vehicle body or the differential 107 may be considered, but if this is done, the area around the differential 107 may become larger due to the support means. , resulting in lower ground clearance. especially,
In the case of four-wheel drive, the lower ground clearance of the rear wheels, which are often used off-road, has a negative impact on driving performance.

Therefore, the object of this invention is to provide a four-wheel drive vehicle that is compact and allows a stable differential limiting mechanism to function.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a four-wheel drive vehicle in which power from the engine is distributed and transmitted to the front wheels and the rear wheels, respectively. The connecting part between the input propeller shaft and the output propeller shaft to be transmitted is rotatably supported by a center bearing member supported in the center of the vehicle body, and the connection part between the input propeller shaft and the output propeller shaft is supported on the inner periphery of this center bearing member. The connecting portion is provided as a differential limiting mechanism that limits differential rotation when differential rotation occurs.

[Operation] In such a four-wheel drive vehicle, the power from the engine distributed by the distribution device is transmitted to one side to the front wheels and the other to the rear wheels.

Next, when a differential occurs between the rear wheel drive system and the front wheel drive system during a turn, the differential is absorbed by the differential limiting mechanism and torque is transmitted to the rear wheels. Therefore, smooth turning is possible.

[Embodiment] Hereinafter, an embodiment of this invention will be described in detail with reference to the drawings of FIGS. 1 and 2.

In the figure, 1 indicates an engine of a four-wheel drive vehicle 3, and 5 indicates a distribution device, and one power distributed by the distribution device 5 is transmitted to the front wheels 9 via a power transmission path 7 of the front wheel drive system. The other power is transmitted to the axle 9a and the other power is transmitted to the axle 13a of the rear wheel 13 via the power transmission path 11 of the rear wheel drive system.

The power transmission path 11 of the rear wheel drive system includes an input side propeller shaft 15 that continues to the distribution device 5, an output side propeller shaft 19 that continues to the differential 17 on the rear wheel 13 side, and each of the input side and output side. A center bearing member 21 rotatably supports the propeller shafts 15, 19, and an outer sleeve 23 of the center bearing member 21 is mounted on a strength member 25 located near the center of the vehicle floor. Further, the inner sleeve 27 of the center bearing member 21 is rotatable with the outer sleeve 23 via a bearing 29, and the inner side of the inner sleeve 27 is supported by both side walls 31 and 33 of the sleeve 27 to maintain a watertight state. The sealed chamber 37 of the differential limiting mechanism 35 is
It is becoming. The sealed chamber 37 is filled with a viscous fluid such as silicone oil, and a plurality of rotary plates 39 and 41 that are relatively rotatable are provided facing each other. One rotating plate 41 is connected to the inner sleeve 27.
The other rotary plate 39 is engaged with the input shaft 43, and the side wall 33 is connected to the inner sleeve 27. The input shaft 43 follows the input propeller shaft 15 , and the side wall 33 engaged with the inner sleeve 27 follows the output propeller shaft 19 . Thereby, the differential limiting mechanism 35 constitutes a connecting portion that connects the input propeller shaft 15 and the output propeller shaft 19. In other words, the connecting portion, that is, the differential limiting mechanism 35 has the function of transmitting power from the input propeller shaft 15 to the output propeller shaft 19 and limiting the power during differential rotation.

Note that 47 indicates a universal joint.

In the four-wheel drive vehicle configured in this manner, power from the engine 1 is distributed by the distribution device 5, and one is transmitted to the front wheels 9 via the power transmission path 7 of the front wheel drive system. In addition, the other power is transmitted to the rear wheels 13 via the power transmission path 11 of the rear wheel drive system, making it possible to travel by four-wheel drive.

Next, when turning, when the rotation of the power transmission path 11 of the rear wheel drive system becomes higher than that of the front wheel drive system and a rotation difference occurs between the two axles 9a, 13a, the rotation difference is caused by the rotation of each rotating plate 39, 41. The torque is absorbed by the relative rotation of and transmitted to the output propeller shaft 19. This allows the propeller shaft to rotate smoothly without causing excessive twisting.

In this case, since the differential limiting mechanism 35 is incorporated into the center bearing member 21, stable torque transmission can be reliably performed without eccentricity even when the propeller shaft rotates at high speed. Also, in terms of space, since there is nothing around the differential 17, clearance with the gasoline tank, etc. is also advantageous, and there is no problem in terms of ground clearance.

[Effects of the invention] As explained above, the four-wheel drive vehicle of this invention has the following effects.

(a) Since the differential limiting mechanism is incorporated into the center bearing member, it is possible to achieve compactness, and the arrangement structure around the differential is simple, ensuring the desired ground clearance.

(b) Since the differential limiting mechanism is supported by the center bearing member, it is possible to minimize the amount of eccentricity at high speeds, enabling stable torque transmission, and making it possible to maintain the strict precision required in machining. It doesn't have to be necessary.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional explanatory diagram of the main parts of the present invention, Fig. 2 is a schematic plan configuration diagram showing the entire vehicle, and Fig. 3 is a schematic plan configuration diagram similar to Fig. 2 showing the conventional example. . Explanation of main drawing symbols, 1...Engine, 7...
Power transmission path, 9... Front wheel, 11... Power transmission path, 13... Rear wheel, 15... Input side propeller shaft, 19... Output side propeller shaft, 21...
...Center bearing member, 35...Differential limiting mechanism.

Claims (1)

[Scope of claim for utility model registration] In a four-wheel drive vehicle that distributes and transmits power from the engine to the front wheels and rear wheels, the connection between the input-side propeller shaft and the output-side propeller shaft that transmits power to the front wheels or rear wheels. is rotatably supported by a center bearing member supported in the center of the vehicle body, and when differential rotation occurs between the input propeller shaft and the output propeller shaft on the inner circumference of the center bearing member, this differential rotation is detected. A four-wheel drive vehicle, characterized in that the connecting portion is provided as a differential limiting mechanism.