JPH04237638A - Differential gear - Google Patents

Abstract

PURPOSE:To improve steering performance and travel stability by constructing a differential gear in such a way as to be capable of controlling the torque of lateral wheels according to the speed and steering angle of a vehicle so as to control the position of the vehicle. CONSTITUTION:An existing differential gear 29 is provided with a toroidal type continuously variable transmission mechanism having an input disk 30 with a toroid face 30a formed thereto, an output disk 32 with a toroid face 32a formed opposedly to the toroid face 30a, and a roller 33 tiltable between the opposed input disk 30 and output disk 32. The roller 33 is provided with the appropriate tilting direction and angle by a controller 37 and an actuator 36 according to the vehicle speed and a steering angle so as to increase the driving torque of a driving wheel in the turning direction of a vehicle and to decrease the driving torque of a driving wheel on the opposite side to the turning direction.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a differential device that can control the attitude of a vehicle by controlling the torque of the left and right wheels according to the speed and steering angle of the vehicle.

0002

[Prior Art] As is well known, a differential gear (final reduction gear) is
It transmits rotation at an appropriate rate to the left and right drive wheels when the vehicle turns.

0003

However, when the vehicle turns, the attitude of the vehicle fluctuates, resulting in poor maneuverability and running stability.

0004

[Means for Solving the Problems] The present invention solves the above problems, and is characterized by a ring gear that meshes with a drive pinion on the input shaft, and a side gear provided on the drive shaft. and a differential pinion that is supported by the ring gear via a spider and meshes with the side gear, wherein the ring gear is provided with an input disk having a toroidal surface formed thereon, and an output disk formed with the toroidal surface is connected to the input disk. an actuator that rotates the roller, the roller being rotatably disposed via a tilting shaft and spline-fitted onto the drive shaft so as to be in frictional contact between the facing input disk and the output disk; and a controller that operates the actuator according to the speed and steering angle of the vehicle.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the drawings. In FIG. 1, 29 indicates a differential device, the structure of which is as follows. That is, 10 is a drive pinion, which is provided at the tip of the input shaft 10a, and is rotatably supported by the housing 11 via bearings 12 and 13. Further, the drive pinion 10 is connected to the ring gear 1
4, and this ring gear 14 is fixed to a differential case 16 via bolts 15.

[0006] Inside the differential case 16, left and right side gears 17 and 18 are arranged. These side gears 17
, 18 are connected to drive wheels via drive shafts 19, 20, respectively. Furthermore, within the differential case 16, there are four differential pinions 21, which are connected to the side gears 17, 1.
It is arranged so that it meshes with 8. The differential pinion 21
is supported by the differential case 16 via a cross-shaped spider 23. The differential case 16 is rotatably supported by the housing 11 via left and right bearings 24.

According to the present invention, in the differential mechanism having the well-known structure as described above, the ring gear 14 is provided with an input disk 30 having a toroidal surface 30a formed thereon. This input disk 30 extends integrally with the side gear 18 and is connected to the drive shaft 2.
It is rotatably supported via a needle bearing 31 on a cylindrical shaft 27 that is spline-fitted to the outer periphery of the cylinder.

32 is an output disk, and the toroid surface 3
2a is formed and is spline-fitted to the cylindrical shaft 27 on the drive shaft 20 facing the input disk 30. A roller 33 that makes frictional contact with the toroid surfaces 30a and 32a is rotatably disposed between the input disk 30 and the output disk 32 through a tilting shaft 34, as shown in FIG. The actuator 36 is connected to the arm 35 to form a toroidal continuously variable transmission mechanism so as to tilt the roller 33 left and right.

In FIG. 2, 37 is a controller. The controller 37 receives the detection signals of the vehicle speed V and the steering angle θ, and selects the appropriate roller 33 at that time based on the values of the vehicle speed V and the steering angle θ set from the map shown in FIG.
The actuator 3 is tilted so as to have a tilting direction and a tilting angle of
6 to provide an activation signal.

Next, the operation of the above structure will be explained. When the vehicle is traveling straight, as shown in FIG. 2, the rollers 33 of the toroidal continuously variable transmission mechanism maintain a neutral position between the input disk 30 and the output disk 32, and the rollers 33 move from the input disk 30 to the output disk 32. Power is transmitted at a ratio of 1:1, and the power input from the input shaft 10a is equally distributed to both drive shafts 19 and 20 via the differential device 29, driving the left and right drive wheels.

When the vehicle turns left, the controller 37 operates the actuator 36 to tilt the roller 33 to the left, as shown in FIG. Due to this tilting of the roller 33, the distance r2 between the contact point of the roller 33 that contacts the toroid surface 30a on the input disk 30 side and the rotation axis of the drive shaft 20, and the distance r2 of the roller 33 that contacts the toroid surface 32a on the output disk 32 side. The distance r1 between the contact point and the rotational axis of the drive shaft 20 has a relationship of r2<r1, and the speed is changed so that the rotation of the input disk 30 becomes faster and the rotation of the output disk 32 becomes slower. Therefore, the right drive wheel 41 becomes as if the brake is applied and the drive torque decreases, and the drive torque of the left drive wheel 40 on the opposite side increases to control the attitude of the vehicle when turning left.

When the vehicle turns to the right, as shown in FIG. 4, the roller 33 tilts in the opposite direction to that when turning to the left.
The speed changes with the relationship r2>r1, and the left driving wheel 40 is applied with a brake, and the driving torque decreases, and the driving torque of the right driving wheel 41 on the opposite side increases, changing the attitude of the vehicle when turning right. It's about controlling.

[0013]

As described above, according to the present invention, a conventional differential gear is provided with a toroidal type continuously variable transmission mechanism, and the rollers of the toroidal type continuously variable transmission mechanism are tilted in an appropriate direction according to the vehicle speed and steering angle. Since the system applies a tilt angle to reduce the drive torque of the drive wheels in the turning direction of the vehicle and increases the drive torque of the drive wheels on the opposite side to the turning direction, the attitude of the vehicle when turning is controlled. This has the advantage of significantly improving maneuverability and running stability.

[Brief explanation of the drawing]

[Figure 1] Overall diagram of the present invention

[Fig. 2] An explanatory diagram of the operation of the present invention in a straight running state

[Fig. 3] An explanatory diagram of the action of the present invention when turning left

[Fig. 4] An explanatory diagram of the action of the present invention when turning to the right

[Figure 5] Control map of the present invention

[Explanation of symbols]

10 Drive pinion 14 Ring gear 17 Side gear 18 Side gear 19 Drive shaft 20 Drive shaft 21 differential pinion 29 Differential device 30 Input disk 30a Toroid surface 32 Output disk 32a Toroid surface 33 Roller 34 Tilt axis 36 Actuator 37 Controller

Claims (1)

[Claims] [Claim 1] A ring gear that meshes with a drive pinion on an input shaft, a side gear provided on the drive shaft,
In a differential device including a differential pinion that is supported by the ring gear via a spider and meshes with the side gear, the ring gear is provided with an input disk on which a toroidal surface is formed, and an output disk on which a toroidal surface is formed is opposed to the input disk. a roller spline-fitted onto the drive shaft and in frictional contact between opposing sides of the input disk and output disk is rotatably disposed via a tilting shaft; an actuator for rotating the roller; A differential limiting device comprising: a controller that operates the actuator according to speed and steering angle.