JPH10169758A - Differential device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a differential device at a low cost. SOLUTION: Flange 39 provided on output shafts 35 are urged in a rotary case 14 to the direction of holding a ball 31 therebetween to transit rotation with the frictional force of the ball 31 thereto. The ball 31 which revolves around the rotation axis of the rotary case 14 with the rotation of the rotary case 14 is held in a storage room 30 to be rotatable when a difference in load torque occurs between both output shafts 35 and a difference in torque occurs between right and left franges 39, 39. When rotating torque is received from an input shaft 15, the ball 31 revolves to rotate both output shafts 35 in the same direction. When a difference in outside load torque occurs between both output shafts 35, the ball 31 rotates while revolving, so that both output shafts 35 can be operated by subtracting the revolution due to the rotation from the rotation due to the revolution of the mutual output shafts 35. Low-cost manufacture is ensured because no bevel gear is used as usual.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a differential gear.

[0002]

2. Description of the Related Art Conventionally, differentials for driving wheels of automobiles are known as this type of differential. Less than,
A description will be given based on FIG. A rotating case 4 is rotatably supported in the main body housing 2 via a bearing 3 and an input shaft 5 is arranged in a direction orthogonal to the rotation direction. The input shaft 5 and the rotating case 4 are used for deceleration. Bevel gear 6
Are linked by A pin 4A penetrates through the rotating case 4 in a direction perpendicular to the direction of the rotation axis, and a pair of small bevel gears 8 is rotatably supported at both ends of the pin 4A. The rotating case 4 is provided with a pair of output shafts 7 on both sides around the pin 4A, and meshes the small bevel gears 8, 8 at two places of the large bevel gear 9 fixed to the end of each output shaft 7. As a result, when the small bevel gear 8 rotates, the large bevel gear 9 performs differential rotation in the opposite direction.

When the rotational torque from the input shaft 5 is transmitted to the rotating case 4 via the reduction bevel gear 6, the small bevel gear 8 revolves around the rotation center of the rotating case 4, and the output shafts 7, 7 are rotated.
Are turned in the same direction. When there is a difference between the external load torques on the output shafts 7, 7, the small bevel gear 8 rotates with the revolution,
That amount is added to or subtracted from the rotation caused by the revolution, and the mutual output shafts 7, 7 are made differential.

[0004]

In the above-described conventional differential device, a bevel gear, which is difficult and expensive to machine, is used to make the output shafts different from each other. There was a problem of becoming high. The present invention
The present invention has been made in view of the above problems, and has as its object to provide a differential device that can be manufactured at low cost.

[0005]

[Means for Solving the Problems]

<Invention of Claim 1> According to the invention of claim 1, a rotating case that rotates by receiving a torque from an input shaft, and a rotatably incorporated in the rotating case and their end faces coaxially opposed in the rotating case. A pair of output shafts, wherein when a difference in external load torque occurs between the two output shafts, the two output shafts can be differentiated.
A retainer portion that can rotate with the rotating case is disposed between the two output shafts, and a sphere is held by the retainer portion at a position distant from the rotating shaft of the rotating case so that the sphere can rotate freely. A differential device characterized in that it can be slidably contacted with an end face of an output shaft.

According to a second aspect of the present invention, there is provided the differential device as set forth in the first aspect, further comprising an urging means for pressing an end face of the output shaft against the sphere. is there.

[0007]

Actions and effects of the present invention

According to the first aspect of the present invention, the sphere is held at a position distant from the rotation axis of the rotating case. Orbits in orbit. In addition, the sphere can freely rotate with respect to the retainer so that it can revolve while revolving. Furthermore, since this sphere can slide on the end faces of both output shafts, when the sphere revolves, the flanges on both sides of the sphere receive frictional force from the sphere in the same direction, and both output shafts move in the same direction. Rotated. On the other hand, when the sphere rotates, the flange portions on both sides receive frictional force in opposite directions, and both output shafts are rotated in opposite directions. Therefore, when the sphere rotates while revolving, one of the output shafts is rotated by the rotation in addition to the rotation due to the revolution, and the other output shaft is rotated by the rotation due to the rotation due to the revolution, and the rotation between the two output shafts is generated. Causes a difference in rotation speed. That is, the rotation of the output shaft due to the torque from the input shaft and the rotation due to the difference in the external load torque are added and subtracted from the two output shafts, and the two output shafts are differentiated. In this way, both output shafts can be made differential without using bevel gears,
The manufacturing cost is not required, and the entire differential can be reduced in price.

According to the second aspect of the present invention, the output shaft is pressed against the sphere by the biasing means.
The frictional force between the output shaft and the sphere is stabilized.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the differential device of the present invention is applied to a differential of an automobile will be described below with reference to the accompanying drawings. A pair of bearing holes 12, 12 are arranged on the left and right sides of FIG. Are rotatably supported. On the right side of the main body housing 11 in FIG. 1, an input bearing portion 16 is formed above the bearing hole 12 in the figure, and a bearing 17 provided in the input bearing portion 16 is provided in a direction orthogonal to the rotation axis direction of the rotation case 14. A shaft 15 is rotatably supported.

The input shaft 15 is integrally provided with a bevel gear 18 at its tip. The other side of the input shaft 15 opposite to the bevel gear 18 is connected to a drive shaft from an engine (not shown).

The rotating case 14 has two cast parts 19
A disc-shaped retainer 21 is sandwiched between the bases 19 made of R and 19L, and the three members are integrated by jointly fastening bolts 22. Protrusions 20, 20 are formed in the cast parts 19 L, 19 R of the base 19 in a direction opposite to the direction of the retainer 21. It is supported rotatably. In addition, on the left side of the base 19 in FIG.
3 is formed, and a bevel gear 24 is attached thereto by bolting, and meshes with the bevel gear 18 of the input shaft 15 described above. The bevel gears 18 and 24 have a rotation direction of 9
In addition to the 0 degree conversion, deceleration is also performed due to the difference in the number of teeth.

The base 19 has an internal space 25 divided into two rooms by a retainer 21, and insertion holes 26, 26 for opening the internal space 25 outward are formed at the centers of the protrusions 20, 20, respectively. Have been. In addition, insertion hole 2
Receiving portions 27, 27 protruding toward the retainer 21 side are formed at the edges of the inner space 6, 6 on the side of the internal space 25, and wave washers 29, 29 described later can be slidably contacted with the flat surface at the tip.

[0013] As shown in FIG.
One housing chamber 30 is provided, and a ball 31 for a generally commercially available ball bearing is housed therein. The storage chambers 30 are uniformly arranged at positions away from the center of rotation of the rotating case 14 and penetrate the retainer 21 in the axial direction. As shown in FIG. 1, the inner surface of the accommodation room 30 is rounded and widened toward the center of the axial direction corresponding to the ball 31, and the center of the ball 31 is aligned with the center of the accommodation room 30 to accommodate the ball. The chamber 30 is rotatably accommodated in the accommodation chamber 30 in a state of protruding from both openings 32, 32 of the chamber 30 to both sides of the retainer 21. In addition, the retainer 21 has a plurality of through holes 33 on the periphery thereof for passing the bolt 22 described above. The retainer 21 can be divided into two parts at the center in the axial direction for the convenience of processing and assembling the storage chamber 30.

Output shafts 35 are arranged on the rotating case 14 on both sides of the retainer 21 in the direction of the rotation axis. The output shaft 35 performs spline processing on the tip end of a rod-shaped main body 36 extending into the internal space 25 through the bearing hole 12 of the main body housing 11 and the insertion hole 26 of the rotating case 14 so that the press-contact flat plate 37 cannot be rotated. Attached to
The clip 38 is used to prevent the clip from coming off. The press contact plate 37 has a flange portion 39 centering on the insertion hole into the rod-shaped main body 36. The flange portion 39 is sandwiched between the retainer 21 and the receiving portion 27 in the internal space 25, is urged toward the retainer 21 by the elastic force of the wave washer 29, and is uniformly contacted with the four balls 31. I have.
The output shaft 35 has an end opposite to the press-contact flat plate 37 connected to a shaft of a drive wheel (not shown) of the vehicle.

Next, the operation of the present embodiment will be described. When the input shaft 15 is rotated by receiving the driving torque of the engine, the rotation is transmitted to the rotating case 14 via bevel gears 18 and 24, and the rotating case 14 rotates. Then
The ball 31 in the accommodation room 30 of the retainer 21 also rotates together. Here, since the accommodation chamber 30 for accommodating the ball 31 is located at a position away from the rotation center of the rotating case 14, the ball 31 revolves on a trajectory around the rotation center when the rotating case 14 rotates. This rotation is indicated by arrow A in FIG. Since the flange portions 39 of the output shaft 35 are frictionally connected to both sides of the ball 31, when the ball 31 revolves, the flange portions 39 on both sides receive the frictional force F in the same direction as shown in FIG. , Both output shafts 35 are rotated in the same direction. Thus, both drive wheels of the vehicle rotate at the same rotational speed, and the vehicle goes straight.

When the vehicle tries to turn a curve during traveling, a difference occurs in the external load torque applied to the drive wheels due to the rotation difference between the inner wheel and the outer wheel. In this case, both output shafts 35,
35 are twisted in opposite directions by the torque difference. Here, since the ball 31 is rotatable in the accommodation room 30, it can also rotate. This rotation is indicated by the arrow B in FIG. When the ball 31 rotates, as shown in FIG. 5, a friction force W is applied to the flange portions 39 on both sides in opposite directions, so that the two output shafts 35 are rotated in opposite directions. Therefore,
When the ball 31 rotates while revolving, the one output shaft 35 is rotated by the rotation in addition to the rotation by the revolution,
The other output shaft 35 is rotated by its own rotation to the rotation of its revolution, and a difference in the number of rotations is generated between the two output shafts 35. That is, both output shafts 35 are differential. Thus, the vehicle can smoothly travel on a curve by making a difference between the rotations of the inner wheel and the outer wheel.

As described above, in this embodiment, both output shafts 3
Since the both can be operated without providing a bevel gear between 5, 35, the cost of the expensive bevel gear can be reduced,
The entire differential can be made inexpensive.

<Other Embodiments> The present invention is not limited to the above-described embodiments. For example, the following embodiments are also included in the technical scope of the present invention.
In addition to the following, various changes can be made without departing from the scope of the invention.

(1) In this embodiment, a wave washer is used to press the flange portion 39 against the ball 31. For example, as shown in FIG. A flange 42 is provided against which the inner 41 of the bearing 40 that supports the main body 36 abuts. Part 39 with ball 3
It is good also as composition which presses on 1.

(2) In the present embodiment, four balls 31 are provided in the retainer 21, but the number may be one. However, if the number is two or more, a load is uniformly applied to the axial direction of the flange portion 39, so that a bending force is not applied to the output shaft 35, and the rotation can be smoothly transmitted.

(3) The ball 31 is not limited to the ball 31 of the ball bearing. However, if it is a steel ball for a ball bearing that is generally commercially available as in this embodiment,
Because it is inexpensive, the differential can be made inexpensive. The material may be resin, rubber, or the like. However, if the material is a metal such as a steel ball of a ball bearing, there is no need to worry about creep deformation, wear, and the like.

(4) In addition to the present embodiment, as an arrangement for transmitting rotation by friction without using a bevel gear, for example, a commercially available conical roller for a conical roller bearing may be used, and an output shaft may be used. May be formed in a conical shape corresponding thereto and connected by frictional force.

(5) In the present embodiment, a differential for an automobile is illustrated, but the present invention can be applied to a differential device in general.

[Brief description of the drawings]

FIG. 1 is a sectional view of a differential device according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of a retainer provided with a ball and a flange portion.

FIG. 3 is a perspective view of a state in which a flange portion is abutted on a ball.

FIG. 4 is a plan view showing the direction of the frictional force between the ball and the flange during the revolution.

FIG. 5 is a plan view showing the direction of the frictional force between the ball and the flange during rotation.

FIG. 6 is a sectional view showing a modification.

FIG. 7 is a sectional view of a conventional differential device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Differential (differential device) 14 ... Rotating case 15 ... Input shaft 21 ... Retainer (retainer part) 29 ... Wave washer (biasing means) 31 ... Ball (sphere) 35 ... Output shaft

Claims (2)

[Claims] 1. A rotating case that receives torque from an input shaft to rotate, and a pair of output shafts that are rotatably incorporated in the rotating case and whose end faces face each other coaxially in the rotating case, A differential device capable of differentially driving both output shafts when an external load torque difference occurs between the two output shafts, wherein a retainer portion that can rotate with the rotary case is provided within the rotary case. The sphere is held at the retainer portion at a position distant from the rotation axis of the rotating case so as to freely rotate, and the sphere can be slidably contacted with the end faces of both output shafts. A differential device characterized by that: 2. An urging means for pressing an end face of said output shaft against said sphere is provided.
The differential as described.