JPH11280863A - Toroidal continuously varriable transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toroidal continuously variable transmission in which a faucet fitting part between an output disc and an output gear is located on the input disc side facing the output disc so as to prevent inclination of the output disc and capable of stably controlling gear ratio. SOLUTION: An output gear 21 fitted on a main shaft 3 of a toroidal continuously variable transmission at a substantially center position, so as to be relatively movable, has a hollow shaft part 30 which is extended along the main shaft 3. A faucet fitting part 31 constituting a fitting part between the hollow shaft part 30 and the output shaft 5 together with a spline fitting part 32, is located at a position distant from the abutting part between the output disc 5 and the gear body 22, and accordingly, it is possible to efficiently restrain the inclination of the output disc 5. Since the positional relationship between the output disc 5 and a power roller is not changed, it is possible to stably control gear ratio.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applicable to a power transmission section of a vehicle or the like, and is a toroidal in which the rotation of an input shaft is steplessly changed via a tiltable power roller and output to an output shaft. The present invention relates to a continuously variable transmission.

[0002]

2. Description of the Related Art Conventionally, as a toroidal type continuously variable transmission,
A set or a plurality of toroidal transmission units including an input disk driven by the input shaft, an output disk disposed opposite to the input disk and connected to the output shaft, and a power roller frictionally contacting both disks are provided on the same shaft. 2. Description of the Related Art Toroidal-type continuously variable transmissions arranged in sets are known. In this toroidal-type continuously variable transmission, by changing the tilt angle of the power roller, the rotation of the input disk can be transmitted to the output disk at a continuously variable speed.

As such a toroidal-type continuously variable transmission, for example, as shown in FIGS. 2 and 3, a so-called double-cavity toroidal-type continuously variable transmission in which two sets of toroidal transmission portions are arranged on the same shaft. There is something called a machine. FIG. 2 is a schematic view of a double-cavity toroidal continuously variable transmission, and FIG. 3 is a cross-sectional view showing details of one toroidal transmission section of the double-cavity toroidal continuously variable transmission shown in FIG.

In the double-cavity toroidal type continuously variable transmission shown in FIG. 2, two sets of toroidal transmission portions 1 and 2 are arranged on a main shaft 3. The toroidal transmission unit 1 is provided with an input disk 4, an output disk 5 arranged opposite to the input disk 4, and a friction member disposed between the input disk 4 and the output disk 5 and having a toroidal curved surface on both disks 4, 5. And a power roller 6 to be engaged. Similar to the toroidal transmission unit 1, the toroidal transmission unit 2 includes an input disk 7, an output disk 8 disposed opposite to the input disk 7, and an input disk 7 disposed between the input disk 7 and the output disk 8. And a power roller 9 frictionally engaged with the toroidal curved surfaces 7 and 8. Each of the toroidal transmission units 1 and 2 is provided with two power rollers 6 and 9, respectively. Each of the power rollers 6 and 9 is rotatable about its own rotation axis 10, and the tilt axis 1 is orthogonal to the rotation axis 10.
1 (perpendicular to the plane of the paper).

[0005] The input shaft 13 is arranged on the same axis as the main shaft 3 so that the power from the engine is supplied to the torque converter 1.
2 is input to the input shaft 13. In the toroidal transmission units 1 and 2, the input disks 4 and 7 can be displaced in the axial direction of the main shaft 3 via the ball spline 17 and can rotate integrally with the main shaft 3. A loading cam 14 having a cam roller 15 is provided at the tip of the input shaft 13. By the action of the cam, the toroidal transmission unit 1 connects the input disk 4 to the power roller 6 according to the magnitude of the input torque. A pressing thrust force is generated. As shown in FIG. 3, a thrust bearing 16 is interposed between the main shaft 3 and the loading cam 14, so that the main shaft 3 can rotate relative to the loading cam 14, but is integrally formed in the axial direction. It is connected to. When the thrust force is generated, the main shaft 3 is pulled toward the input shaft 13 due to the reaction, and the input disk 7 is pressed against the power roller 9 in the toroidal transmission portion 2. Therefore, the thrust force sandwiches the power rollers 6, 9 between the input disks 4, 7 and the output disks 5, 8, and provides a frictional engagement force according to the magnitude of the transmission torque. A part of the rotational force from the loading cam 14 is transmitted to the input disk 4 of the toroidal transmission unit 1 via the cam roller 15, and the rotation of the input disk 4 is transmitted to the output disk 5 via the rotation of the power roller 6. . On the other hand, the remainder of the rotational force from the loading cam 14 is transmitted to the input disk 7 of the toroidal transmission unit 2 via the ball spline 17 and the main shaft 3, and
The rotation of the input disk 7 is transmitted to the output disk 8 via the rotation of the power roller 9.

In the toroidal transmission units 1, 2, the power rollers 6, 9 are tilted around the tilt shaft 11, so that the rotation of the input disks 4, 7 is controlled by the output disks 5, 8 in accordance with the tilt angle θ. The speed is continuously changed and transmitted. The power rollers 6, 9 are rotatably and swingably supported with respect to a trunnion (not shown), and can cope with the axial displacement of the main shaft 3 caused by the thrust force.

At the neutral position where the rotation axis 10 of the power rollers 6, 9 intersects with the axis of the main shaft 3, the tilt angle θ of the power rollers 6, 9 maintains the state at that time, and the gear ratio is Holds the value of When the trunnion is moved in the axial direction of the tilting shaft 11 during torque transmission, the power rollers 6, 9 are accordingly displaced in the tilting axis direction, and the power rollers 6, 9 and the input disks 4, 7 and the output disk are moved. The contact position with 5, 8 is displaced from the contact position in the neutral position. As a result, the power rollers 6 and 9 receive the tilting force from both disks, and tilt around the tilt shaft 11 in a direction and a speed corresponding to the moving direction and the moving amount of the tilt shaft 11. . When such tilting occurs, the radius drawn by the frictional contact points between the input disks 4 and 7 with the power rollers 6 and 9 and the radius drawn by the frictional contact points between the output disks 5 and 8 with the power rollers 6 and 9 are calculated. , The stepless speed change is performed. In the tilt control of the power rollers 6, 9, the displacement of the trunnion in the tilt axis direction is controlled by a controller (not shown) by operating an actuator (not shown) so as to achieve the target gear ratio.

The output disks 5 and 8 respectively have a hollow shaft portion 40 extending integrally from both sides of the gear body 22 of the output gear 21 so as to transmit torque from the power rollers 6 and 9 and rotate together with each other. Spline fit. The spline fitting portion 42 is formed by meshing a spline formed on the outer periphery of the hollow shaft portion 40 with a spline formed on the inner periphery of the fitting hole 43 of the output disk 5.
The output gear 21 is rotatably supported by the casing 19 via an angular bearing 23 having an inner ring 24a and an outer ring 24b. The output gear 21 is provided rotatably with respect to the main shaft 3. Hereinafter, the output disk 5,
The support of the output disk 8 will be described with respect to the output disk 5 of the toroidal transmission unit 1, but the same applies to the output disk 8.

Roller bearing 46 for rotatably supporting main shaft 3
Is disposed on the inner peripheral portion of the output disk 5 on the side of the front end portion 45 facing the input disk 4. The roller bearing 46 is a bearing that allows a slight axial movement of the main shaft 3. Also,
The position of the output disk 5 in the thrust direction is determined by abutting the back surface 18 on the side of the output gear 21 with the abutting portion 29 via the spacer 28. The spacer 28 is in contact with the inner ring 24 a of the bearing 23. The radial position of the output disk 5 is determined by fitting the output disk 5 to the outer peripheral surface of the hollow shaft portion 40 of the output gear 21 at the inner peripheral portion near the rear surface 18 by the spigot fitting portion 41. The output disk 5 receives a thrust force as indicated by an arrow A and a radial force as indicated by an arrow B from the power roller 6. The thrust force indicated by the arrow A is supported from the bearing 23 to the casing 19 via the spacer 28, and the radial force indicated by the arrow B is supported from the bearing 23 to the casing 19 via the hollow fitting portion 41 via the hollow shaft portion 40. Is done.

[0010] The torque transmitted to the output disks 5 and 8 is extracted from the chain transmission device 20, that is, the output gear 21, through the chain 26 and the sprocket 25, and to the counter shaft 27 (Fig. 2) as an output shaft. A disc spring 49 is interposed between the loading cam 14 and the input disk 4 to press the input disks 4, 7 against the power rollers 6, 9 even when no input torque is applied. The main shaft 3 is formed with an oil passage 47 formed so as to extend in the axial direction, and an oil passage 48 penetrating in a radial direction from the oil passage 47 to supply lubricating oil to each contact portion and the rotating portion. I have.

Regarding the support of the output disk, see
There is a toroidal type continuously variable transmission disclosed in JP-A-92655, JP-A-5-39830, or JP-A-8-61453. In these toroidal-type continuously variable transmissions, the input shaft is rotatably supported with a slight axial movement with respect to the transmission cover, and a pair of output discs are rollers with respect to the outer periphery of the input shaft. It is rotatably supported via a bearing, and is serration-fitted to a boss portion of an output gear disposed so as to be rotatable relative to the input shaft between the two output disks. The output gear is rotatably supported on the transmission cover via a ball bearing with respect to the casing. Japanese Patent Application Laid-Open No. 6-147282 discloses that a pair of input disks or output disks arranged with their back surfaces facing each other is fitted with a cylindrical portion extending between the two disks so that both disks can be connected to one disk. There has been disclosed a toroidal-type continuously variable transmission which has a rigid structure and prevents both disks from falling down.

The conventional toroidal type continuously variable transmission as described above has the following problems. That is,
In the toroidal type continuously variable transmission, when the contact points between the power rollers 6, 9 and the input disks 4, 7 and the output disks 5, 8 change, the gear ratio changes. Looking at the support of the output disk 5, in the thrust direction, the abutment 2
There is no particular restraint other than the abutment at 9, and it is only restricted in the radial direction by the spigot fitting portion. The diameter of the abutting portion 29 on the back surface 18 of the output disk 5 is substantially equal to the diameter D of the spigot fitting portion 41, and is much smaller than the outer diameter of the output disk 5 in terms of layout. The spigot fitting portion 41 between the output disk 5 and the output gear 21 exists near the abutting portion 29, and the fitting length L is also shorter than the diameter D of the fitting portion. Further, the fitting of the spigot fitting portion 41 and the spline fitting portion 42 is a gap fitting from the viewpoint of the workability of assembly, and the spline fitting portion 42 fits with a larger gap than the spigot fitting portion 41. It has become.

Therefore, for example, when a force is exerted to tilt the output disks 5 and 8 from the power rollers 6 and 9, the output disks 5 and 8 are connected to the output gear 5 at the abutting portion 29 and the spigot portion 30 which are close to each other. The effect of preventing an inclination with respect to 21 is poor. A bearing 46 disposed between the main shaft 3 and the output disks 5 and 8 is provided.
Is located substantially at the center of the long main shaft 3 to rotatably support the main shaft 3, and it is difficult to expect that the radial position of the output disk 5 is positioned with high accuracy. Since the spline fitting portion 42 is farther from the abutting portion 29 than the spigot fitting portion 41 and the gap in the spline fitting portion 42 is larger than the gap in the spigot portion 41, the output disks 5 and 8 tend to be inclined. is there. Due to such a support structure of the output disks 5, 8, the geometrical arrangement of the output disks 5, 8 and the power rollers 6, 9 changes to change the speed ratio, and the originally intended speed ratio cannot be obtained. And a stable gear ratio cannot be obtained. Another problem is that fretting wear occurs in the contact portions due to repeated contact between the back surfaces of the output disks 5 and 8 and the spacer 28.

[0014]

Therefore, in the toroidal type continuously variable transmission, the abutting portion and the spigot fitting portion, which substantially position the output disk with respect to the output gear, are spaced apart from each other. By providing such an arrangement, when an external force is applied to the output disk, the output disk can be prevented from inclining due to the gap existing at the fitting portion between the output disk and the output gear. There are issues to be addressed.

[0015]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems, and a spigot fitting portion in a fitting portion where an output disk and an output gear are fitted, and an output disk and an output gear. By disposing the abutting portion with the gear body at a distance from each other, the inclination of the output disk with respect to the output gear is suppressed, so that the toroidal type continuously variable transmission does not shift at an unintended gear ratio. An object of the present invention is to provide a toroidal-type continuously variable transmission that can stably maintain a predetermined gear ratio.

According to the present invention, there is provided a first input disk to which the torque of an input shaft is transmitted via a loading cam.
A main shaft fixed to one end of the input disk so as to be integrally fixed in the rotation direction and movable in the axial direction, a second input disk fixed to the other end of the main shaft, and opposed to both input disks. A first and a second output disk disposed so as to be relatively rotatable with respect to the main shaft, and the input disk disposed between the input disk and the output disk and according to a tilt angle with respect to the two disks; A power roller for continuously changing the rotation of the output disk and transmitting the output disk to the output disk; an output gear connected to the both output disks;
And an output shaft operatively connected to the output gear, wherein the output gear is disposed between the two output disks and extends from the gear body along the main shaft from a gear body abutting against each of the output disks; A hollow shaft portion that fits into a fitting hole of each of the output disks; a fitting portion that fits the output disk and the hollow shaft portion is a spline fit that is located on the gear body side of the output gear; The present invention relates to a toroidal-type continuously variable transmission comprising a mating portion and a spigot fitting portion located on the input disk side.

In the toroidal-type continuously variable transmission, each of the output disks is abutted against the gear body of the output gear via a spacer.

Since the toroidal type continuously variable transmission according to the present invention is configured as described above, it operates as follows. That is, each output disk is abutted against the gear body of the output gear, thereby positioning the output disk with respect to the output gear in the thrust direction. Further, since the fitting portion where the output disk and the hollow shaft portion are fitted is composed of a spline fitting portion located on the gear body side of the output gear and a spigot fitting portion located on the input disk side. The positioning of the output disk with respect to the output gear in the radial direction is performed by the spigot fitting portion. Since the abutting portion of the output disk against the output gear and the spigot fitting portion are separated from each other, for example, when the output disk is inclined by the pressing force from the power roller, a reaction force opposing the inclination is likely to be generated. Therefore, the inclination of each output disk is effectively suppressed.
The amount by which the power roller is operated with respect to the power roller so that the rotation of the input disk is continuously variable and transmitted to the output disk is the tilt angle with respect to both disks. By preventing the tilt of the output disk, a change in the positional relationship between the power roller and the output disk is suppressed, and as a result, the tilt angle does not change to an unintended angle. Therefore, the gear ratio of the toroidal type continuously variable transmission is
It is controlled accurately according to the tilt angle.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a toroidal type continuously variable transmission according to the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a main part of an embodiment of a toroidal type continuously variable transmission according to the present invention. In the toroidal type continuously variable transmission shown in FIG. 1, the main shaft, the output disk, and the related structure of the output gear are shown, and other structures not shown are the conventional toroidal type continuously variable transmission shown in FIGS. The structure shown in FIG.
And the same reference numerals as those used in FIG.

In the embodiment of the toroidal-type continuously variable transmission according to the present invention shown in FIG. 1, only the toroidal transmission unit 1 is shown, but as shown in FIG. It is provided with. However, since the two toroidal transmission units 1 and 2 are symmetrically arranged, only the toroidal transmission unit 1 will be described below. The output gear 21 rotatably fitted to the main shaft 3 includes a gear main body 22 and a hollow shaft portion 30 extending from the gear main body 22 along the main shaft 3. Therefore, the output disk 5
It is supported by the hollow shaft part 30.

The fitting portion between the output disk 5 and the hollow shaft portion 30 of the output gear 21 includes a spigot fitting portion 31 located on the input disk 4 side facing the output disk 5 and the gear body 2.
And a spline fitting portion 32 located on the second side. The spigot fitting portion 31 is formed by fitting a spigot fitting surface 34 on the hollow shaft portion 30 side with a spigot fitting surface 35 on the fitting hole 33 side of the output disk 5 and is relatively precise. Are fitted by a small gap. The spline fitting portion 32 is formed by meshing a spline 36 formed on the outer periphery of the hollow shaft portion 30 with a spline 37 formed on the inner periphery of the fitting hole 33 of the output disk 5. The torque can be transmitted between the disk 5 and the output gear 21. The main shaft 3 has a roller bearing 4
6 rotatably supported by the output disk 5. The portion of the hollow shaft portion 30 closest to the gear body 22 is a bearing fitting portion 30a into which the inner ring 24a of the bearing 23 fits.

The output disk 5 is in contact with the gear main body 22 of the output gear 21 by a butting portion 29. A spacer 39 is interposed in the abutting portion 29. The abutting portion 29 is in contact with the inner ring 24 a of the bearing 23 because of the layout in which the abutment portion 29 contacts the output gear 21 rotatably supported on the casing 19 via the bearing 23. The output disk 5 is positioned with respect to the output gear 21 in the thrust direction via the abutting portion 29 on the gear body 22, and in the radial direction on the hollow shaft portion 30 via the spigot fitting portion 31. I have. The spigot fitting portion 31 is a fitting portion having a small gap when viewed microscopically, as compared with the spline fitting portion 32 that transmits torque. The spline fitting portion 32 located close to the abutment portion 29 has a large gap, so that the output disk 5
A large counterforce is not generated against the inclination of the spigot, but the spigot fitting portion 31 with a small gap is
Since it is arranged as far as possible from 9, it is possible to apply to the output disk 5 the most efficiently a force which opposes the output disk 5 from tilting. Therefore, when an external force such as a pressing force from the power roller 6 acts on the output disk 5, the output disk 5
1 is greatly suppressed, and the positional relationship between the output disk 5 and the power roller 6 does not change. As a result, it is possible to control the speed ratio according to the tilt angle θ of the power roller 6, and to maintain a constant speed ratio, it is possible to maintain a stable speed ratio.

Also, since the inclination of the output disk 5 with respect to the output gear 21 can be prevented, the output disk 5
Rear surface 18 which is the side surface on the side of output gear 21 and spacer 39
Is always in close contact. Therefore, the back 1 of the output disk 5 as seen in a conventional toroidal-type continuously variable transmission
It is possible to prevent the occurrence of fretting wear due to repeated contact and separation of the spacer 8 with the spacer 28.

[0024]

According to the toroidal type continuously variable transmission of the present invention, as described above, the spigot fitting portion forming the fitting portion where the output disk and the output gear fit, and the output disk contacts the gear body. Since the output disk is disposed on the input disk side remote from the abutting portion, a force against the output gear against the inclination of the output disk with respect to the output gear is efficiently generated, and the inclination of the output disk can be suppressed. Therefore, the positional relationship between the output disk and the power roller does not fluctuate due to the inclination of the output disk, so that the toroidal type continuously variable transmission does not shift at an unintended gear ratio, and the power roller tilt angle is reduced. The speed ratio can be accurately controlled according to the speed ratio, and a stable speed ratio can be maintained when the speed ratio is maintained constant. Further, since the inclination of the output disk is suppressed, problems such as fretting wear due to repeated contact between the output disk and the spacer do not occur.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of a toroidal type continuously variable transmission according to the present invention.

FIG. 2 is a diagram illustrating an example of a conventional toroidal-type continuously variable transmission.

FIG. 3 is an enlarged sectional view showing a part of a conventional toroidal type continuously variable transmission.

[Explanation of symbols]

 1, 2 Toroidal transmission unit 3 Main shaft 4, 7 Input disk 5, 8 Output disk 6, 9 Power roller 11 Tilt shaft 13 Input shaft 14 Loading cam 19 Casing 21 Output gear 22 Gear body 29 Butt contact part 30 Hollow shaft part 31 Spigot fitting part 32 Spline fitting part 33 Fitting hole 34,35 Spigot fitting surface 36,37 Spline 39 Spacer

Claims (2)

[Claims] A first input disk to which torque of an input shaft is transmitted via a loading cam, and one end of the first input disk which is integrally fixed in a rotational direction and is movable in an axial direction. A second input disk fixed to the other end of the main shaft, first and second output disks disposed opposite to the two input disks and rotatable relative to the main shaft; A power roller disposed between an input disk and the output disk and for continuously changing the rotation of the input disk and transmitting the rotation to the output disk according to a tilt angle with respect to the two disks;
An output gear connected to the output disks; and an output shaft operatively connected to the output gear, wherein the output gear is disposed between the output disks and a gear body abutting against each of the output disks. A hollow shaft portion extending from the gear main body along the main shaft and fitted into a fitting hole of each of the output disks; A toroidal-type continuously variable transmission comprising a spline fitting portion located on the gear body side of a gear and a spigot fitting portion located on the input disk side. 2. The toroidal-type continuously variable transmission according to claim 1, wherein each of said output disks is abutted against said gear body of said output gear via a spacer.