JP2891110B2 - 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 two continuously variable transmission portions disposed on a common input shaft, and a disc spring disposed at one end of the input shaft to apply a preload to the continuously variable transmission portions. When,
A toroidal type continuously variable transmission of a double cavity type, comprising: a loading nut disposed at the end of the input shaft to tighten the disc spring; and a bearing for supporting the end of the input shaft. Relates to an advantageous arrangement of the disc spring and the loading nut in the toroidal type continuously variable transmission.

[0002]

2. Description of the Related Art As a toroidal type continuously variable transmission of the double cavity type, for example, the applicant of the present application has disclosed in Japanese Patent Laid-Open Publication No. Hei.
The one shown in FIG. 6 disclosed in No. 9439 is conventionally known,
The transmission comprises two input disks 1, 2 and two output disks 3, 4, where the input disk 1
Defines a continuously variable transmission portion 6 by defining a cavity circle facing the output disk 3 and sandwiching a pair of transmission friction rollers 5 (only one is shown in the figure) between them. 2 also forms a cavity circle facing the output disk 4 and constitutes another continuously variable transmission portion 8 by sandwiching a pair of transmission friction rollers 7 (only one is shown in the figure) between them. ing.

The input disks 1 and 2 are drivingly coupled to both ends of an input shaft 9 common to the two continuously variable transmission portions via ball splines 10 so as to be movable in the axial direction. Is driven and connected via a normal spline to a drive gear 11 rotatably fitted to the input shaft 9, and a driven gear 12 meshing with the drive gear 11 is connected to a first output shaft on the side of the input shaft 9. A gear 14 formed at the other end of the first output shaft 13 and a second output shaft arranged on the same axis as the input shaft 9 are drivingly coupled to one end of the first shaft 13 via a normal spline. 15 together with the output gear 16 formed at the end of the first and second output shafts 13,
15 meshes with an intermediate gear on an intermediate shaft (not shown) disposed on the side of the shaft 15.

With such a configuration, the drive torque input from the engine (not shown) to the input shaft 9 via the torque converter (not shown) is transmitted from the two input disks 1 and 2 to the two output disks via the friction rollers 6 and 7. The power is transmitted to the disks 3 and 4 in parallel, and further from the output disks 3 and 4 to the second output shaft 15 via the drive gear 11, the driven gear 12, the first output shaft 13, the gear 14, the intermediate gear and the output gear 16. It is transmitted to the outside of the transmission and output to the driving wheels of the vehicle. The rotation of the input shaft 9 due to the input driving torque is caused by the tilting of the friction rollers 6 and 7 around the axis passing through the center of the cavity circle and between the input / output disks 1 and 3 and between the input / output disks 2 and 4. The gear 14 rotates in the same direction as the driven gear 12 meshing with the drive gear 11, that is, in the same direction as the input shaft 9. From the output gear through the intermediate gear
16 and thus to the second output shaft 15 and hence the input shaft 9
Is taken out from the second output shaft 15 as an output rotation in the same direction as.

Here, the drive torque from the torque converter is applied to a cam flange 18 inserted in series between a flange 17 formed at the end of the input shaft 9 on the input disk 1 side and the input disk 1. The cam roller 19 is transmitted to the input disk 1 and the input shaft 9 via the cam roller 19, and the cam roller 19 moves in the circumferential direction of the cam flange 18 in accordance with the magnitude of the driving torque input to the cam flange 18, and The input disk 1 is pressed against the output disk 3 under the support of the flange 18. On the other hand, between a loading nut 20 fastened to the end of the input shaft 9 on the input disk 2 side and the input disk 2, a disc spring 21 and an annular preload adjusting plate 22 are inserted in series. The disc spring 21 is tightened by the loading nut 20 and the compression amount is appropriately adjusted by changing the thickness of the preload adjusting plate 22.
Presses the input disk 2 toward the output disk 4 and presses the input shaft 9 in a direction opposite to the pressing direction of the input disk 2.

With this configuration, a driving torque is input between the friction roller 5 and the input / output disks 1 and 3 and between the friction roller 7 and the input / output disks 2 and 4 of the two continuously variable transmission portions 6 and 8. When the driving torque is input while the pre-load is applied by the compressed disc spring 21 while the compression is not performed, the cam roller 19 applies a pressing force of a magnitude corresponding to the driving torque, thereby transmitting the driving torque. A frictional force with no excess or shortage is generated.

[0007]

In the conventional toroidal-type continuously variable transmission, the coned disc spring 21 of the input shaft 9 is required based on the basic requirement of minimizing the outer dimensions of the transmission. The end on the side where is disposed is the second output shaft 15
The second output shaft 15 is supported by a ball bearing 23 which is inserted into the end on the output gear 16 side via a needle bearing and supports the end on the output gear 16 side of the second output shaft 15. A concave portion 2a is formed on the rear surface of the input disk 2 adjacent to the plate 22, and the disc spring 21 and the preload adjusting plate 22 are accommodated in the concave portion 2a on the rear surface of the input disk 2.

In such a structure, however, the friction roller 5 and the input / output disks 1, 3 and the friction roller 7 and the input / output disks 2,
When a large pressing force is applied between the 4
Of the two input disks 1 and 2 in which the relatively deep spline grooves 10a are formed, the concave portions 2a are formed and the rigidity is relatively low, and at the same time the cam rollers 19 are formed.
If the input disk 2 is not supported from behind by the cam flange 18, a considerable internal stress is generated due to stress concentration, particularly in the vicinity of the spline groove 10 a. However, the possibility of cracking near the spline groove 10a could not be denied.

[0009] In order to solve this problem, a disc spring is used.
It is conceivable to increase the rigidity of the input disk 2 by disposing the recess 21a from the input disk 2 by disposing the preload adjusting plate 22 and the preload adjusting plate 22 outside the input disk 2. By simply disposing the plate 22 outside the input disk 2, the disc spring 21 and the loading nut 20 for tightening the disc spring 21, and the ball bearing 23 that supports the end of the input shaft 9 on the side where the disc spring 21 is disposed. In order to prevent interference with the transmission, it is necessary to shift the ball bearings 23 outward in the axial direction, and it is necessary to increase the outer dimensions of the transmission in the axial direction of the input shaft 9, thereby making the outer dimensions of the transmission possible. A new problem arises in that the basic requirement of keeping it as small as possible cannot be satisfied.

[0010]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a toroidal type continuously variable transmission which advantageously solves the above-mentioned problems of the conventional double cavity type toroidal type continuously variable transmission. According to another aspect of the present invention, there is provided a toroidal-type continuously variable transmission that includes two continuously variable transmission portions disposed on a common input shaft and a plate that is disposed at one end of the input shaft and applies a preload to the continuously variable transmission portions. A spring, a loading nut disposed at the end of the input shaft to tighten the disc spring, and supporting the end of the input shaft via an output shaft located on the same axis as the input shaft. In a toroidal type continuously variable transmission of a double cavity type including a bearing, the disc spring and the loading nut are arranged at the same position as the bearing in the axial direction of the input shaft. It is characterized in that disposed radially inward relative to the inner circumferential surface of the bearing together.

The toroidal-type continuously variable transmission according to the present invention includes a first output shaft provided with an output rotation in the same direction as the rotation direction of the input shaft from the two continuously variable transmission portions; A second output shaft, which is located on the same axis and has one end supported by the bearing and supporting the end of the input shaft, the first output shaft and the second output shaft. The output shaft may be connected via a chain.

[0012]

In the toroidal type continuously variable transmission according to the present invention, the disc spring and the loading nut are supported at the end of the input shaft via the output shaft located on the same axis as the input shaft. The bearing and the input shaft are arranged in the same position in the axial direction of the input shaft, and are arranged radially inward with respect to the inner peripheral surface of the bearing.
Even if no recess is formed on the back surface of the input disk of the continuously variable transmission portion adjacent to the disc spring, the bearing is moved outward in the axial direction to prevent interference with the disc spring and a loading nut for tightening the disc spring. Without displacing, the disc spring can be arranged at the end of the input shaft.

[0013]

In the toroidal type continuously variable transmission according to the present invention, the disc spring and the loading nut are supported at the end of the input shaft via the output shaft located on the same axis as the input shaft. The bearing and the input shaft are arranged in the same position in the axial direction of the input shaft, and are arranged radially inward with respect to the inner peripheral surface of the bearing.
Even if no recess is formed on the back surface of the input disk of the continuously variable transmission portion adjacent to the disc spring, the bearing is moved outward in the axial direction to prevent interference with the disc spring and a loading nut for tightening the disc spring. Without displacing, the disc spring can be arranged at the end of the input shaft.

The toroidal-type continuously variable transmission according to the present invention includes a first output shaft provided with an output rotation in the same direction as a rotation direction of the input shaft from the two continuously variable transmission portions; A second output shaft which is located on the same axis, one end of which is supported by the bearing, and which supports the end of the input shaft, the first output shaft and the second output shaft. If the shaft and the shaft are connected via a chain, the second output shaft can be provided without providing an intermediate gear supported by a conventional intermediate shaft located on the side of the first output shaft and the second output shaft. The shaft can be rotated in the same direction as the first output shaft, and while satisfying the requirement that the rotation directions of the input shaft and the second output shaft coincide with each other, the space for the bearing supporting the intermediate shaft is reduced by the second shaft. The end of the input shaft through one end of the output shaft It can be devoted for supporting the bearing.

The toroidal-type continuously variable transmission according to the present invention includes a first output shaft provided with an output rotation in the same direction as a rotation direction of the input shaft from the two continuously variable transmission portions; A second output shaft which is located on the same axis, one end of which is supported by the bearing, and which supports the end of the input shaft, the first output shaft and the second output shaft. If the shaft and the shaft are connected via a chain, the second output shaft can be provided without providing an intermediate gear supported by a conventional intermediate shaft located on the side of the first output shaft and the second output shaft. The shaft can be rotated in the same direction as the first output shaft, and while satisfying the requirement that the rotation directions of the input shaft and the second output shaft coincide with each other, the space for the bearing supporting the intermediate shaft is reduced by the second shaft. The end of the input shaft through one end of the output shaft It can be devoted for supporting the bearing.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a cross-sectional view showing the entire configuration of a first embodiment of a toroidal-type continuously variable transmission according to the present invention, and FIG.
FIG. 3 is a cross-sectional view showing, in an enlarged scale, a portion related to the present invention in the configuration of the continuously variable transmission according to the embodiment. FIG. FIG. 4 is an end view, and FIG. 4 is a cross-sectional view showing the gear train of the continuously variable transmission of the above-described embodiment in a developed state. The toroidal type continuously variable transmission according to this embodiment is also a double-cavity type, and has a configuration substantially similar to that of the conventional example shown in FIG. , And are denoted by the same reference numerals.

That is, the toroidal type continuously variable transmission of this embodiment also includes two input disks 1 and 2 and two output disks 3 and 4, where the input disk 1
Defines a continuously variable transmission portion 6 by defining a cavity circle facing the output disk 3 and sandwiching a pair of transmission friction rollers 5 (only one is shown in the figure) between them. 2 also forms a cavity circle facing the output disk 4 and constitutes another continuously variable transmission portion 8 by sandwiching a pair of transmission friction rollers 7 (only one is shown in the figure) between them. ing.

The input disks 1 and 2 are drivingly coupled to both ends of an input shaft 9 common to the two continuously variable transmission portions via ball splines 10 so as to be movable in the axial direction. Is driven and connected via a normal spline to a drive gear 11 rotatably fitted to the input shaft 9, and a driven gear 12 meshing with the drive gear 11 is connected to a first output shaft on the side of the input shaft 9. A gear 14 formed at the other end of the first output shaft 13 and a second output shaft arranged on the same axis as the input shaft 9 are drivingly coupled to one end of the first shaft 13 via a normal spline. As shown in FIG. 4, the output gear 16 formed at the end of the intermediate gear 15 meshes with an intermediate gear 25 on an intermediate shaft 24 disposed beside the first and second output shafts 13 and 15. doing.

With this configuration, the driving torque input from the engine (not shown) to the input shaft 9 via the torque converter 26 and the planetary gear type forward / reverse switching mechanism 27 is:
In the same manner as in the above conventional example, the power is transmitted to the second output shaft 15 and
It is output outside the transmission and is eventually delivered to the drive wheels of the vehicle. The rotation of the input shaft 9 due to the input drive torque is also continuously variable and transmitted to the second output shaft 15 in the same manner as in the above-described conventional example. It is taken out from the second output shaft 15.

Further, a cam flange 18 and a cam roller 19 are interposed between the input disk 1 and a flange 17 formed at an end of the input shaft 9 on the input disk 1 side. A disc spring 21 and an annular preload adjusting plate 22 are interposed between a loading nut 20 fastened to the end of the input disk 9 on the side of the input disk 2 and the input disk 2 in series. The drive torque from the forward switching mechanism 27 is transmitted to the input disk 1 and thus to the input shaft 9 via the cam flange 18 and the cam roller 19, and the cam roller 19 corresponds to the magnitude of the drive torque input to the cam flange 18. To move in the circumferential direction of the cam flange 18 and press the input disk 1 toward the output disk 3 under the support of the cam flange 18, while the loading nut
The disc spring 21 is tightened by 20 and the compression amount is appropriately adjusted by changing the thickness of the preload adjusting plate 22.
Presses the input disk 2 toward the output disk 4 and presses the input shaft 9 in a direction opposite to the pressing direction of the input disk 2.

Therefore, also in this embodiment, the drive torque of the two continuously variable transmission portions 6, 8 is between the friction roller 5 and the input / output disks 1, 3 and between the friction roller 7 and the input / output disks 2, 4. While not input, the above compressed disc spring
When a driving torque is input while a preload is applied by 21, a pressing force having a magnitude corresponding to the driving torque is applied by the cam roller 19, so that a sufficient amount of frictional force is generated in transmission of the driving torque.

In this embodiment, the end of the input shaft 9 on the side where the disc spring 21 is disposed is the same as the above-described conventional example.
Needle bearing in the end of the output shaft 15 on the output gear 16 side
The casing is formed by a ball bearing 23 that is inserted through the second output shaft 15 and supports the end of the second output shaft 15 on the output gear 16 side.
On the other hand, a concave portion 15a is formed at the end of the output shaft 15 on the output gear 16 side, and the end is shortened, so that the inner circumferential surface of the ball bearing 23 is radially inward. This allows the disc spring 21 and the loading nut 20 to be arranged at the same position as the ball bearing 23 in the axial direction of the input shaft 9 and to have a radius relative to the inner peripheral surface of the ball bearing 23. It is arranged inward in the direction. Therefore, in this embodiment, the input disk 2 of the continuously variable transmission portion 8 adjacent to the disc spring 21 and the preload adjusting plate 22 has a sufficient thickness in the vicinity of the spline groove 10a because it has no concave portion on the rear surface thereof. Further, without the ball bearing 23 being displaced outward in the axial direction, interference between the ball bearing 23 and the disc spring 21 and the loading nut 20 is prevented.

Therefore, according to the toroidal type continuously variable transmission of this embodiment, the input disk 2 of the continuously variable transmission portion 8 adjacent to the disc spring 21 and the preload adjusting plate 22 has a sufficient thickness near the spline groove 10a. Therefore, even if a large pressing force is applied to the input disk 2 from the friction roller 7, the occurrence of cracks in the input disk 2 can be effectively prevented, and the ball bearings 23 are displaced outward in the axial direction. Since it is not performed, it is possible to satisfy the requirement that the outer size of the transmission be kept as small as possible.

FIG. 4 shows the first embodiment of the present invention.
The meshing state of the gear 14 on the output shaft 13, the intermediate gear 25 on the intermediate shaft 24, and the output gear 16 on the second output shaft 15 is shown in an expanded manner, and as shown, one end of the second output shaft 15 The ball bearing 23 supporting the portion is fitted into a hole 29a of the casing 29, the ball bearing 30 supporting one end of the first output shaft 13 is fitted into a hole 29b of the casing 29, and the Roller bearings 31 supporting one end are fitted into holes 29c of the casing 29, and are supported by the casing 29, respectively. Also, FIG.
When the end of the casing 27 is viewed from the direction, the arrangement of the holes 29a, 29b and 29c into which the bearings are fitted is shown. As is clear from FIGS. In the arrangement, the distance between the ball bearings 23 and the roller bearings 31 and the distance between the roller bearings 31 and the ball bearings 30 are so close that substantially no further increase in the bearing outer diameter can be performed.

Therefore, the rotation direction of the input shaft 9 and that of the second output shaft 15 are made to coincide with each other, and the ball bearing 23 is accommodated inside the ball bearing 23 in the radial direction to accommodate the disc spring 21 and the loading nut 20. Assuming that the inner diameter is not reduced, in order to extract a larger output torque from the second output shaft 15, the ball diameter and the outer diameter of the ball bearing 23 are enlarged to further increase the load bearing capacity of the ball bearing 23. In this case, in the configuration of the above-described embodiment, it is necessary to shift the position of the intermediate shaft 24 outward (to the left in FIG. 3), and it is not possible to satisfy the requirement of minimizing the outer dimensions of the transmission. There was an inconvenience.

FIG. 5 shows a second embodiment of the present invention in which the above-mentioned disadvantages have been solved. In FIG. 5, the same parts as those in the first embodiment are designated by the same reference numerals. That is, this embodiment has a configuration substantially similar to that of the first embodiment, except that the connection between the first output shaft 13 and the second output shaft 15 is connected to the gear 14 in the first embodiment. Instead of using a gear train composed of an intermediate gear 25 and an output gear 16, a chain that extends over a sprocket 32 provided at an end of a first output shaft 13 and a sprocket 33 provided at an end of a second output shaft 15. (Silent chain in the illustrated example) 34.

In the second embodiment, the intermediate shaft 24 and the roller bearing 31 for supporting the intermediate shaft 24 in the first embodiment, which have become unnecessary due to the connection by the chain 34, are eliminated. Because of this, it is possible to increase the outer diameter of the ball bearing 23 by providing a sufficient space, so that the ball bearing 23 having a larger outer diameter and a larger ball diameter than that of the first embodiment is connected to the second output shaft. Used to support 15 ends.

Therefore, according to the toroidal-type continuously variable transmission of the second embodiment, the rotation directions of the input shaft 9 and the second output shaft 15 are made to coincide with each other, and the disc spring is provided radially inward of the ball bearing 23. 21 and the loading nut 20 can be accommodated, and the requirement that the outer dimensions of the transmission be kept as small as possible can be satisfied.In addition, the ball diameter and outer diameter of the ball bearing 23 can be increased. Since the load bearing capacity of the ball bearing 23 is further enhanced as compared with the first embodiment, a larger output torque can be taken out from the second output shaft 15.

Although the present invention has been described with reference to the illustrated examples, the present invention is not limited to the above-described example. For example, the connection between the first output shaft 13 and the second output shaft 15 according to the second embodiment is described. When a large output torque is taken out from the second output shaft 15 while using a gear train including the gear 14, the intermediate gear 25, and the output gear 16 as in the first embodiment without using a chain, the second output Another ball bearing 35 (see FIG. 2) which supports the intermediate portion of the shaft 15 and shares the load from the second output shaft 15 with the ball bearing 23, The bearing is shifted to the position closer to the bearing 23 (the position closer to the left in FIG. 2) to increase the load sharing of the ball bearing 35, and to expand the ball diameter and the outer diameter of the ball bearing 35 to increase the load supporting capacity. If you do this, Also, it is possible to meet the requirements of keeping as small as possible outer dimensions of the transmission. In the present invention, if necessary, in addition to the disc spring 21 and the loading nut 20, a preload adjusting plate 22 is further provided.
May also be accommodated inside the ball bearing 23 in the radial direction.

[0030]

As described above, according to the toroidal type continuously variable transmission of the present invention, it is possible to eliminate the necessity of forming a concave portion on the back surface of the input disk of the continuously variable transmission portion adjacent to the disc spring, and to crack the input disk. Can be effectively prevented, and the need to shift the bearing outward in the axial direction can be eliminated, thereby satisfying the requirement of minimizing the outer size of the transmission as much as possible.

The toroidal-type continuously variable transmission according to the present invention includes a first output shaft provided with an output rotation in a direction opposite to a rotation direction of the input shaft from the two continuously variable transmission portions; A second output shaft which is located on the same axis, one end of which is supported by the bearing, and which supports the end of the input shaft, the first output shaft and the second output shaft. If the shaft and the shaft are connected via a chain, the space for the bearing that supports the intermediate shaft is reduced by the amount of space for the bearing that supports the intermediate shaft while satisfying the requirement that the rotation directions of the input shaft and the second output shaft match. (2) Since it can be used for a bearing that supports the end of the input shaft via one end of the output shaft, without considering the increase in the interval between the first output shaft and the intermediate shaft, Supports one end of the second output shaft Since the outer diameter of the bearing and the diameter of the rolling element such as a ball can be increased, and the load-bearing capacity of the bearing can be increased, the above-mentioned requirement can be satisfied while keeping the outer dimensions of the transmission as small as possible. 2
It is possible to obtain a larger output torque from the output shaft.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an overall configuration of a first embodiment of a toroidal type continuously variable transmission according to the present invention.

FIG. 2 is a cross-sectional view showing, in an enlarged manner, a portion related to the present invention in the configuration of the continuously variable transmission according to the first embodiment.

FIG. 3 is an end view of only the casing of the continuously variable transmission according to the first embodiment as viewed from the direction of arrow III in FIG. 1;

FIG. 4 is an exploded cross-sectional view showing a gear train of the continuously variable transmission according to the first embodiment.

FIG. 5 is a cross-sectional view showing, in an enlarged manner, a portion related to the present invention in the configuration of the second embodiment of the toroidal-type continuously variable transmission according to the present invention.

FIG. 6 is a cross-sectional view illustrating the configuration of a conventional toroidal-type continuously variable transmission.

[Description of Signs] 6,8 continuously variable transmission section 9 input shaft 13 first output shaft 15 second output shaft 20 loading nut 21 disc spring 22 preload adjustment plate 23 ball bearing 34 chain

Claims (2)

(57) [Claims] 1. A continuously variable transmission (6, 8) disposed on a common input shaft (9), and a preload applied to one end of the input shaft to apply a preload to the continuously variable transmission. Disc Springs (21)
When, a loading nut cinching the disc spring is disposed on said end of said input shaft (20), the said input shaft
A bearing (23) supporting the end of the input shaft via an output shaft (15) located on one axis line , wherein the disc spring ( 21) and loading nut (20)
Are arranged in the same direction as the bearing (23) in the axial direction of the input shaft (9), and are disposed radially inward with respect to the inner peripheral surface of the bearing. Continuously variable transmission. 2. A first output shaft (13) provided with an output rotation in the same direction as a rotation direction of the input shaft (9) from the two continuously variable transmission portions (6, 8); A second position which is located on the same axis and supported at one end by the bearing (23) and supporting the end of the input shaft;
The toroidal-type continuously variable transmission according to claim 1, further comprising an output shaft (15), the first output shaft (13) and the second output shaft (13).
A toroidal-type continuously variable transmission characterized by being connected to an output shaft (15) via a chain (34).