JP3454156B2 - Toroidal type continuously variable transmission - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvement of a bearing for an input / output shaft of a toroidal type continuously variable transmission used in a vehicle or the like.

[0002]

2. Description of the Related Art As a structure for supporting an input / output shaft of a toroidal type continuously variable transmission, a structure shown in Japanese Patent Application No. 7-153442 is known.

To explain this, as shown in FIG. 6, a pair of toroidal input disks 1,
The output disk 2 is arranged coaxially with the input shaft 3,
By changing the inclination angles of the pair of power rollers 4 and 4 pressed against the input disk 1 and the output disk 2, it is possible to set an arbitrary gear ratio steplessly.

The input disc 1 rotates almost integrally with the input shaft 3 via a guide sleeve 8 stopped by a cam roller 5, a cam flange 6 and a loading nut 7, and the input shaft 3 is at the base end side (right side in the figure). ) Is rotatably supported by a tapered roller bearing 10 interposed between the end portion of FIG. 2) and the casing 9, and a needle bearing 12 provided between the guide sleeve 8 and the casing cover 11.

The output disk 2 is connected to an output gear (output shaft) 13 on the back surface (right side in the drawing) and supported rotatably relative to the input shaft 3. The inner circumference of the output disk 2 and the input shaft 3 are connected to each other. A needle bearing 14 interposed between the output shaft 13 and
And tapered roller bearing 15 interposed between the casing and the casing 9.
Is pivoted by.

The tapered roller bearings 10 and 15 are coaxially arranged with their outer rings in contact with each other, and receive the reaction force of the axial force that holds the power roller 4.

The pressure for sandwiching the power roller 4 between the input disk 1 and the output disk 2 is the disc spring 16 provided between the guide sleeve 8 and the cam flange 6 on the tip side of the input shaft 3.
And the cam roller 5 that generates a thrust force that urges the input disk 1 to the right side in the drawing in response to the rotation of the input shaft 3. Due to the initial load of the disc spring 16 and the axial thrust generated by the cam roller 5, the power roller 4 is clamped between the input disc 1 and the output disc 2 and rotates without slipping, and the torque from the input disc 1 is applied to the output disc 2. It is transmitted.

The tapered roller bearings 10 and 15 of the input shaft 3 and the output shaft 13 support the load in the radial direction and the clamping pressure of the power roller 4 (load in the thrust direction) by pressing the outer rings against each other.

[0009]

In this conventional toroidal type continuously variable transmission, the tapered roller bearing 1 supports the input shaft 3 and the output shaft 13, that is, the input / output disks 1 and 2.
Although 0 and 15 are used, the tapered roller bearings 10 and 15 have a high rigidity due to the line contact, and therefore the relative displacement between the input / output disks 1 and 2 and the power rollers 4 and 4 occurs due to dimensional tolerance in manufacturing. However, the input / output disks 1 and 2 cannot be displaced to absorb the positional deviation.

That is, since the input / output disks 1 and 2 and the power rollers 4 and 4 are in contact with each other on their curved surfaces, a slight positional deviation affects the contact position between the input / output disks 1 and 2 and the power rollers 4 and 4. Will end up. Therefore, although the input / output disks 1 and 2 are accurately supported, a difference occurs in the loads received by the power rollers 4 and 4, respectively, and the power roller 4 with the smaller load becomes slippery and the transmission torque is reduced. There is a problem.

An object of the present invention is to prevent the reduction of the transmission torque by absorbing the positional deviation of the power roller due to the dimensional tolerance and the like, while using the tapered roller bearing having high rigidity for supporting the input / output disk. .

[0012]

SUMMARY OF THE INVENTION A first invention is an input disk connected to an input shaft, an output disk connected to an output shaft, and a toroidal shape formed on the facing surfaces of these input / output disks. A power roller sandwiched in the groove,
In a toroidal type continuously variable transmission that includes an input bearing and an output bearing that respectively support the input shaft and the output shaft in a casing, and uses tapered roller bearings in the input bearing and the output bearing, At least one has a centering function.

In a second aspect based on the first aspect, the tapered roller bearing having the aligning function has a convex spherical surface whose outer peripheral surface is centered on the rotation axis of the tapered roller bearing.

According to a third aspect of the present invention, in the second aspect, a washer is provided between the outer peripheral surface of the outer ring and the casing, the washer is fixed to the casing, and a surface of the washer that contacts the outer peripheral surface of the outer ring is an outer peripheral surface of the outer ring. It has a concave spherical shape with the same radius of curvature and center.

In a fourth aspect based on the third aspect, the washer of the input bearing and the washer of the output bearing have an integrated structure.

In a fifth aspect based on the second and third aspects, the center of the centering function is set with respect to the large diameter end face of the outer ring.
Position it in the opposite direction of the conical apex of the roller.

According to a sixth aspect of the present invention, in the first aspect of the present invention, the tapered roller bearing having the aligning function has a concave spherical surface whose outer ring raceway surface has a center on the rotation axis of the tapered roller bearing.

In a seventh aspect based on the first aspect, the center of the centering function for the output disc is located inside the output disc.

[0019]

According to the first to third aspects of the present invention, the positional deviation between the input / output disk and the power roller due to dimensional tolerance in manufacturing is eliminated, and the appropriate contact position between the input / output disk and the power roller is eliminated. Therefore, the desired transmission torque can be secured.

According to the fourth aspect of the invention, most of the thrust loads acting on each bearing can be canceled by the washers, and the load on the casing can be reduced.

According to the fifth aspect of the invention, the bearing can be easily assembled by simply inserting the bearing into the washer without press fitting or the like.

According to the sixth aspect of the present invention, a centering function is provided in the bearing to prevent a decrease in transmission torque due to a positional deviation between the input / output disk and the power roller.

According to the seventh invention, the contact point with the power roller moves greatly even if the output disk has a small swing angle, and the movement in accordance with the position of the power roller is facilitated, so that the input / output disk and the power roller are moved. Positional deviation can be eliminated accurately.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example in which the present invention is applied to the toroidal type continuously variable transmission shown in FIG. 6, in which a tapered roller bearing 20 supporting an input shaft 3 to which an input disk 1 is coupled and an output disk 2 are provided. Combined output gear (output shaft) 13
Mounting surfaces 24 and 25 having convex spherical shapes centered on the rotation axes of the bearings 20 and 21 are formed on the outer peripheral surfaces of both outer rings 22 and 23 of the tapered roller bearing 21 that supports the bearings 21 and 23, respectively. The mounting surfaces 24, 25 are formed on the sides of the outer rings 22, 23 adjacent to each other, but may be formed on the entire outer peripheral surface.

Tapered roller bearings 20 and 21 and casing 2
A ring plate-shaped washer 27 for supporting the tapered roller bearings 20 and 21 is provided between the washer 6 and 6. The washer 27 is a washer having an integral structure that supports both tapered roller bearings 20 and 21,
Surfaces 28 and 29 contacting the mounting surfaces 24 and 25 of the tapered roller bearings 20 and 21 are formed in a concave spherical shape having the same radius of curvature and center as the mounting surfaces 24 and 25, respectively, and the casing 26 is mounted via bolts or the like. Fixed to.

In this case, the center of the centering function with respect to the output shaft 13, that is, the center O of the mounting surface 25 of the tapered roller bearing 21 and the surface 29 of the washer 27 that contacts the mounting surface 25 is the large diameter side of the outer ring 23. It is formed so as to be located at an inner portion of the output disc 2 in the direction opposite to the conical vertex of the roller with respect to the end face 31. In contrast to this, the center of the mounting surface 24 of the tapered roller bearing 20 and the surface 28 of the washer 27 that contacts the mounting surface 24 is centered on the large-diameter side end surface 3 of the outer ring 22.
It is formed so as to come to a predetermined position in the direction opposite to the conical vertex of the roller with respect to 0.

The casing 26 is made of a light alloy such as aluminum, and the washer 27 is made of quenched high hardness steel. Note that the other configurations are the same as those in FIG. 6, and the same reference numerals are given to the same portions.

With this structure, the input / output disks 1 and 2 and the power rollers 4 and 4 are manufactured due to dimensional tolerances in manufacturing.
Even if the positions of
It is solved by the centering function of the tapered roller bearings 20 and 21 and the balance of the forces of the input / output disks 1 and 2 and the power rollers 4 and 4.

That is, the input disk 1 connected to the input shaft 3 and the output disk 2 connected to the output shaft 13 are centered on the centers of the convex spherical mounting surfaces 24, 25 of the tapered roller bearings 20, 21. As shown in FIG. 2, the position of the power rollers 4 and 4 is mechanically balanced against the positional deviation between the power rollers 4 and 4 and the input / output disks 1 and 2, that is, a pair of The input / output disks 1 and 2 move to positions where the loads acting on the power rollers 4 and 4 are equal. Especially, the output disk 2 has the centering point of the disk 2.
Since it is in the vicinity of the center (center O), the contact point with the power rollers 4 and 4 moves greatly even with a small swing angle, and therefore it is easy to move according to the position of the power rollers 4 and 4.

Therefore, it is possible to prevent the transmission torque from being lowered due to a difference in the load received by the power rollers 4 and 4 due to manufacturing dimensional tolerances and the like, and it is possible to secure a desired high transmission torque.

On the other hand, the load required to transmit the torque between the input / output disks 1 and 2 and the power rollers 4 and 4 is very large, and therefore the load acting on the input bearing 20 and the output bearing 21 is large. 20, outer peripheral surfaces of the outer rings 22 and 23 of the output bearing 21 have high surface pressure.
Since the washer 27 that receives 0, 21 has a high hardness, it does not cause wear, adhesion, etc., and does not damage the casing 26.

Further, since the washers of the input bearing 20 and the output bearing 21 are integrally structured, as shown in FIG.
Most of the thrust load acting on 21 can be canceled by the washer 27, and the load on the casing 26 can be reduced.

Further, the centering points of the bearings 20 and 21 are larger than the outer diameters 22 and 23 of the outer diameters 22 and 23, respectively.
Since the bearings 20 and 21 are located in the direction opposite to the conical vertices of the rollers, the bearings 20 and 21 can be easily assembled by simply inserting the bearings 20 and 21 into the washer 27 attached to the casing 26 without press fitting or the like. .

FIG. 4 shows another embodiment, in which a tapered roller bearing 40 for supporting the input shaft 3 to which the input disk 1 is connected and an output gear (output shaft) 13 to which the output disk 2 is connected are supported. Each of the tapered roller bearings 41 has a centering function.

Outer ring raceway surface 4 of the tapered roller bearings 40, 41
The reference numerals 2 and 43 are formed in concave spherical shapes centered at predetermined positions on the rotation axes of the bearings 40 and 41, respectively. Around 4
4, 45 are formed in a convex spherical shape having the same radius of curvature as the outer ring raceway surfaces 42, 43. The inner ring raceways 46, 47 are
The toroidal groove shape having the same radius of curvature corresponding to the shape of the rollers 44 and 45 is formed.

The bearings 40 and 41 are directly attached to the casing 48. Other configurations are the same as those in FIG.

By doing so, the positional deviation between the input / output disks 1 and 2 and the power rollers 4 and 4 due to the dimensional tolerance in manufacturing as shown in FIG. The desired high transmission torque can be secured.

In this case, it is difficult to form the output disk 2 so that the centering point of the output disk 2, that is, the center of the outer ring raceway surface 43 of the bearing 41 is located so far from the bearing 41.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a main part configuration showing an embodiment of the present invention.

FIG. 2 is an operation explanatory view.

FIG. 3 is an operation explanatory view.

FIG. 4 is a cross-sectional view of a main part configuration showing another embodiment.

FIG. 5 is an operation explanatory view.

FIG. 6 is a cross-sectional view of a main part configuration of a conventional example.

[Explanation of symbols]

1 input disk 2 output discs 3 input axes 4 power rollers 5 cam rollers 8 Guide sleeve 11 Casing cover 12 Needle bearing 13 Output shaft 14 Needle bearing 16 Disc spring 20,21 tapered roller bearing 22,23 outer ring 24,25 mounting surface 26 Casing 27 washers 28, 29 sides 30, 31 Large diameter end face 40,41 tapered roller bearings 42,43 Outer ring raceway 46,47 Inner ring raceway

Claims (7)

(57) [Claims] 1. An input disk connected to an input shaft, an output disk connected to an output shaft, a power roller sandwiched between toroidal grooves formed on opposing surfaces of the input and output disks, respectively. In a toroidal type continuously variable transmission that includes an input bearing and an output bearing that respectively support an input shaft and an output shaft in a casing, and uses tapered roller bearings in the input bearing and the output bearing, at least the input bearing and the output bearing. A toroidal-type continuously variable transmission characterized by having an aligning function on one side. 2. The tapered roller bearing having the aligning function,
The toroidal type continuously variable transmission according to claim 1, wherein an outer peripheral surface of the outer ring has a convex spherical shape having a center on a rotation axis of the tapered roller bearing. 3. A washer is provided between the outer peripheral surface of the outer ring and the casing, the washer is fixed to the casing, and a surface of the washer that comes into contact with the outer peripheral surface of the washer has the same radius of curvature and center as the outer peripheral surface of the outer ring. The toroidal type continuously variable transmission according to claim 2, which has a spherical shape. 4. The toroidal type continuously variable transmission according to claim 3, wherein the washer of the input bearing and the washer of the output bearing are integrated. 5. The toroidal type continuously variable transmission according to claim 2, wherein the center of the aligning function is located in the direction opposite to the conical vertex of the roller with respect to the large diameter end face of the outer ring. 6. The tapered roller bearing having the aligning function,
The toroidal type continuously variable transmission according to claim 1, wherein the outer ring raceway surface has a concave spherical shape centered on the rotation axis of the tapered roller bearing. 7. The toroidal type continuously variable transmission according to claim 1, wherein the center of the centering function with respect to the output disc is located inside the output disc.