JPH0343050Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a differential device for a full-time four-wheel drive vehicle.

(Prior Art) This type of four-wheel drive vehicle requires a center differential device to provide a differential function between the front wheels and rear wheels in order to avoid, for example, tight corner braking phenomena. In addition, in the transaxle case of this type of four-wheel drive vehicle, for example, in the case of a front engine, a front differential device for distributing rotation between the left and right front wheels is arranged on the same rotational axis as the center differential device. has been done. As a result, the transaxle case tends to become large, and as a countermeasure to this problem, there is a system in which the front differential is housed within the case of the center differential (for example, see Japanese Patent Laid-Open No. 59-57032). ).

(Problems to be solved by the invention) As mentioned above, the specific structure of the front differential device housed within the case of the center differential device is as follows.
The direction in which the ring gear, sun gear, planetary gear, and front differential, which are the components of the center differential, and the front differential are along their rotation axes (horizontal direction)
are arranged in parallel. For this reason, it is difficult to make the transaxle compact in the left-right direction (vehicle width direction), where it is relatively difficult to secure space, and the problem remains that the transaxle case inevitably becomes larger.

(Means for solving the problems) In order to solve the above problems, the present invention is configured as follows. That is, as is clear from Fig. 1, the differential device of the present invention includes a center differential device 3 for distributing rotation from the transmission to the front wheels and rear wheels, respectively, and a center differential device 3 for distributing rotation from the transmission to the left and right drive wheels on the engine side. The vehicle is equipped with a front or rear differential 20 for distributing. A space surrounded by left and right side gears 7 and 8 built into the case 4 of the center differential 3 and a pinion 9 that meshes with these gears is provided in a space that is integrally connected to one side gear 7. Above front or rear differential gear 2
Contains case 21 of 0. In other words, the center differential 3 and the front or rear differential 2
0 are arranged in parallel in a direction orthogonal to each other's rotation axes.

(Function) According to the above configuration, by arranging the center differential 3 and the front differential 20 in parallel in the direction perpendicular to their mutual rotation axes, the space occupied by the center differential 3 and the front differential 20 in the transaxle case In particular, it is possible to reduce the space in the direction along the axis of rotation (vehicle width direction).

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

First, in Figure 2, which is a cross-sectional view of the inside of the transaxle in a permanent four-wheel drive vehicle with a transversely mounted front engine, the transaxle case 1
Inside, a differential case 4 of a center differential device (hereinafter simply referred to as "center differential") 3 is rotatably supported by a pair of left and right tapered roller bearings 6. A ring gear 5 formed on the outer periphery of the differential case 4 is always in mesh with a drive gear 2a formed on the output shaft 2 of the transmission. Therefore, the rotation of the output shaft 2 of the transmission is transmitted to the differential case 4 of the center differential 3 through the drive gear 2a and the ring gear 5 described above.

As is clear from FIG. 1, which is an enlarged view of a portion of the differential device in FIG.
Inside the differential case 4 are a pair of left and right side gears 7,
8 and a pinion 9 that is always in mesh with these and rotatably supported by a pinion shaft 10 with respect to the differential case 4 are rotatably incorporated. Of these side gears 7 and 8, the side gear 7 located on the left side of the drawing is integrally formed with a differential case 21 of a front differential device (hereinafter simply referred to as "front differential") 20. The center differential 3 is arranged so that its rotation axis is coaxial with the rotation axis of the front differential 20. Moreover, the differential case 21 of the front differential 20 is housed in a space surrounded by both side gears 7 and 8 of the center differential 3 and the pinion 9. Also, this differential case 21
Inside, there is a pair of left and right side gears 22 for configuring the front differential 20, and a pinion shaft 2 that constantly meshes with these and is connected to the differential case 21.
A pinion 23 rotatably supported by 4 is rotatably incorporated therein. In other words, the center differential 3 and the front differential 20 are arranged side by side in a direction perpendicular to their respective rotation axes.

Left and right front wheel drive vehicles 25, which are disposed on the rotation axes of the center differential 3 and the front differential 20, are connected to both side gears 22 of the front differential 20 by spline fitting or the like so that rotation can be transmitted. ing. On the other hand, of the side gears 7 and 8 of the center differential 3, the side gear 8 located on the right side in the drawing has one end (the left end in the drawing) of a cylindrical shaft 11 on its rotation axis by spline fitting or the like. They are centered and connected to each other so that rotation can be transmitted. A ring gear 12 using a hypoid gear is integrally formed on the outer periphery of the shaft 11 near the other end (right end in the drawing).
2. The right end of the shaft is rotatably supported by a tapered roller bearing 13 with respect to the trunk axle case 1.

The drive pinion 14 meshing with the ring gear 12 is arranged such that its rotational axis is perpendicular to the rotational axes of the center differential 3 and front differential 20, and its shaft 15 is connected to one part of the transaxle case 1. It is rotatably supported by a pair of tapered roller bearings 16. The rotation of the drive pinion 14 is transmitted from a propeller shaft (not shown) to the rear wheels through the shaft 15 and a companion flange 17 connected thereto.

That is, the rotation transmitted to the differential case 4 of the center differential 3 is distributed to the front differential 20 and the rear wheels through the pinion shaft 10, the pinion, and both side gears 7, 8. and,
The rotation of the differential case 21 of the front differential 20 is distributed from each front wheel drive shaft 25 to the left and right front wheels through its pinion shaft 24, pinion 23, and both side gears 22.

In the differential system for a four-wheel drive vehicle configured as described above, the rotation transmitted from the output shaft 2 of the transmission to the differential case 4 of the center differential 3 through its drive gear 2a and ring gear 5 is as follows.
As described above, the power is distributed from both side gears 7 and 8 in the differential case 4 to the front differential 20, the cylindrical shaft 11, and the ring gear 12 to the drive pinion 14, respectively. The rotation transmitted to the drive pinion 14 is transmitted to the shaft 15 and companion flange 17 as described above.
It is transmitted to the rear wheels through the front differential 2.
The rotation transmitted to the left and right front wheels is distributed to the left and right front wheels through both side gears 22 in the differential case 21 and the front wheel drive shaft 25 coupled to these side gears.

As described above, the center differential 3 and the front differential 20 in this embodiment are arranged in parallel in a direction perpendicular to their respective rotational axes. The space occupied by the differential 20, particularly in the direction along the axis of rotation (left and right direction in the drawing), can be kept small.

In the above embodiment, a front engine four-wheel drive vehicle has been described, but in a rear engine four-wheel drive vehicle, the power is transmitted from one side gear 8 of the center differential 3 through the cylindrical shaft 11, ring gear 12 and drive pinion 14. The rotation is transmitted to the front wheels, and the front differential 20 functions as a rear differential device for distributing the rotation to the left and right rear wheels, which are drive wheels on the engine side.

(Effects of the invention) As described above, the present invention provides a space between the left and right side gears built into the case of the center differential and the pinion that meshes with the left and right side gears. By accommodating the case of the front or rear differential, which is integrally connected to the other, the center differential and the front or rear differential are installed side by side in a direction perpendicular to their rotational axes. As a result, the space occupied by both differential devices can be reduced, and the transaxle can be made more compact.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention. Figure 1 is an enlarged cross-sectional view of a part of the differential device of a permanent four-wheel drive vehicle, and Figure 2 is an illustration of the inside of the transaxle of a vehicle with a transverse front engine. FIG. 3... Center differential device, 4... Differential case,
7, 8...Side gear, 9...Pinion, 20...
...Front or rear differential, 21...Differential case.

Claims (1)

[Scope of utility model registration request] A center differential device for distributing rotation from the transmission to the front wheels and rear wheels, respectively, and a center differential device arranged so that its rotation axis is coaxial with the rotation axis of the center differential device, and the engine A differential device for a four-wheel drive vehicle comprising a front or rear differential device for distributing rotation to left and right side drive wheels, the left and right side gears being incorporated in the case of the center differential device. A four-wheel drive vehicle characterized in that a case of the front or rear differential device integrally connected to one of the side gears is housed in a space surrounded by a pinion meshing with the front or rear differential gear. Differential device.