JPH06174032A - Toroidal type continuously variable transmission - Google Patents

Abstract

PURPOSE:To obtain a large change gear ratio while suppressing the large size and a heavy weight to the minimum, by connecting two sets of transmission units with a connecting shaft, and making the connecting shaft function as the output shaft of one side transmission unit, while the connecting shaft function as the input shaft of the other side transmission unit. CONSTITUTION:Two sets of transmission units 15a and 15b are combined with a connecting shaft 16, and the connecting shaft 16 is made function as the output shaft of one side transmission unit 15a, while function as the input shaft of the other side transmission unit 15b. The ratios of the rotation speed of an input side disk 2 and an output side disk 4 are regulated by changing the inclination of a power roller 8. By setting the change gear ratios of the transmission units 15a and 15b adequately, a large change gear ratio can be obtained. Consequently, the increase of the weight and the like can be reduced extensively compared to the case of making a single toridal type transmission in a large size so as to obtain a large change gear ratio.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The toroidal type continuously variable transmission according to the present invention is used, for example, as a transmission for an electric vehicle.

[0002]

2. Description of the Related Art The use of a toroidal type continuously variable transmission as schematically shown in FIGS. 3 and 4 has been studied as a transmission for an automobile. The toroidal type continuously variable transmission supports an input side disk 2 concentrically with an input shaft 1 and an output side disk 4 at an end of an output shaft 3 as disclosed in Japanese Utility Model Laid-Open No. 62-71465. Is fixed. On the inner surface of the casing accommodating the toroidal type continuously variable transmission, or on the support bracket provided in this casing, the pivots 5 and 5 which are twisted with respect to the input shaft 1 and the output shaft 3 are centered. Swing trunnions 6, 6 are provided.

The trunnions 6, 6 are provided with the pivots 5, 5 on the outer surfaces of both ends. Further, the base ends of the displacement shafts 7, 7 are supported on the central portions of the trunnions 6, 6, and the trunnions 6, 6 are swung about the pivot shafts 5, 5, so that the displacement shafts 7, The inclination angle of 7 can be freely adjusted.

Power rollers 8, 8 are rotatably supported around displacement shafts 7, 7 supported by the trunnions 6, 6, respectively. And each power roller 8, 8
Are sandwiched between the input side and output side disks 2 and 4.

The inner surfaces 2a, 4a of the input-side and output-side disks 2, 4 which face each other have cross-sections which are arcuate concave surfaces with the pivot 5 as the center. And
The peripheral surfaces 8a, 8a of the power rollers 8, 8 formed on the spherical convex surface are in contact with the inner side surfaces 2a, 4a.

A loading cam type pressurizing device 9 is provided between the input shaft 1 and the input side disc 2, and the pressurizing device 9 elastically directs the input side disc 2 toward the output side disc 4. Is pressed against. This pressurizing device 9
A cam plate 10 that rotates together with the input shaft 1 and a plurality of (for example, four) rollers 12 and 12 held by a cage 11.
It consists of and. One side surface of the cam plate 10 (see FIG. 3).
4 to 4), a cam surface 13 which is an uneven surface extending in the circumferential direction is formed on the outer surface (left side surface of FIGS. 3 to 4) of the input side disk 2 and a similar cam. It forms the surface 14. The plurality of rollers 12, 12 are provided rotatably around an axis in the radial direction with respect to the center of the input shaft 1.

When the toroidal type continuously variable transmission configured as described above is used, when the cam plate 10 rotates with the rotation of the input shaft 1, the cam surface 13 causes the plurality of rollers 12,
12 is pressed against the cam surface 14 on the outer surface of the input side disk 2. As a result, the input side disk 2 is pressed by the plurality of power rollers 8, 8 and at the same time, based on the meshing between the pair of cam surfaces 13, 14 and the plurality of rollers 12, 12. The input side disk 2 rotates. Then, the rotation of the input side disk 2 is transmitted to the output side disk 4 via the plurality of power rollers 8 and the output shaft 3 fixed to the output side disk 4 rotates.

When the rotational speeds of the input shaft 1 and the output shaft 3 are changed, and when deceleration is first performed between the input shaft 1 and the output shaft 3, as shown in FIG. As a result, the trunnions 6, 6 are swung so that the peripheral surfaces 8a, 8a of the power rollers 8, 8 are located near the center of the inner side surface 2a of the input side disk 2 and near the outer periphery of the inner side surface 4a of the output side disk 4. The displacement shafts 7, 7 are tilted so that they contact each other.

On the contrary, when increasing the speed, the trunnions 6 and 6 are swung as shown in FIG. 4, and the peripheral surfaces 8a and 8a of the power rollers 8 and 8 are located inside the input side disk 2. The outer peripheral portion of the side surface 2a and the inner side surface 4a of the output side disk 4
The displacement shafts 7, 7 are tilted so that they are brought into contact with the central portions of the displacement shafts 7, 7, respectively. By setting the inclination angles of the displacement shafts 7, 7 in the middle between FIG. 3 and FIG. 4, it is possible to obtain an intermediate gear ratio between the input shaft 1 and the output shaft 3.

[0010]

SUMMARY OF THE INVENTION The present invention is to increase the degree of freedom of the obtained gear ratio, thereby increasing the practicality and convenience of the toroidal type continuously variable transmission.

In the case of the conventional structure shown in FIGS. 3 to 4, the speed change ratio obtained between the input shaft 1 and the output shaft 3 is determined by the diameters of the disks 2 and 4 on the input side and the output side. Inner side surfaces 2a, 4a and peripheral surfaces 8a, 8a of each power roller 8, 8
Bounded by the radius of curvature of each trunnion 6, 6. Then, in order to obtain a large gear ratio, it is necessary to increase the diameter of each of the disks 2 and 4 and the power rollers 8 and 8. Therefore, if the gear ratio is increased with the structure as shown in FIGS. 3 to 4, the toroidal type continuously variable transmission becomes extremely large and the weight is unavoidably increased.

When a single output shaft is rotationally driven by two types of drive sources having different rotational speeds, it is necessary to eliminate the difference in rotational speed between the two types of drive sources by the transmission. In such a case, when it is necessary to provide a transmission between both drive sources and the output shaft, the structure shown in FIGS. 3 to 4 cannot be adopted as it is.

For example, Japanese Utility Model Laid-Open No. 63-60751 discloses a structure in which two toroidal type continuously variable transmissions are arranged in parallel with each other to increase the transmittable power (torque). It is not possible to deal with the above problems.

The toroidal type continuously variable transmission of the present invention has been invented in view of the above circumstances.

[0015]

In the toroidal type continuously variable transmission of the present invention, the toroidal type continuously variable transmission is arranged so as to be concentric with the input side disc and rotatably supported with respect to the input side disc. An output side disc, a trunnion which is located in a twisted position with respect to the center axes of both the input side and output side discs and swings about a pair of concentric pivots, and a displacement shaft supported by the trunnion, It is provided with a power roller rotatably supported by the displacement shaft and sandwiched between the input side and output side disks, and the inner side surfaces of both the input side and output side disks facing each other are arc-shaped in cross section. Two sets of transmission units each having a concave surface, the peripheral surface of the power roller being a spherical convex surface, and abutting the peripheral surface and the inner side surface are arranged in series, and the output side of one of the transmission units is arranged. An input-side disks disks and other transmission units constitute by being rotatably coupled synchronously.

[0016]

In the case of the toroidal type continuously variable transmission of the present invention configured as described above, a large gear ratio can be obtained by mutually setting the gear ratio of the two transmission units, or by mutually setting the gear ratio. It is possible to rotate one output shaft by two drive sources having different rotation speeds.

[0017]

FIG. 1 shows a first embodiment of the present invention. This toroidal type continuously variable transmission has two sets of transmission units 1.
5a and 15b are connected in series with each other. The structure of each transmission unit 15a, 15b is similar to that of the conventionally known toroidal type continuously variable transmission shown in FIGS. The description is omitted.

Particularly, in the toroidal type continuously variable transmission of the present invention, the two sets of transmission units 15a and 15b are connected by a connecting shaft 16, and the connecting shaft 16 is connected to one side (left in FIG. 1). One of the transmission units 15a functions as an output shaft and the other (right side of FIG. 1) of the transmission unit 15b functions as an input shaft.

In the case of the toroidal type continuously variable transmission of the present invention configured as described above, two sets of transmission units 1 are provided.
A large gear ratio can be obtained by appropriately setting the gear ratios of 5a and 15b. For example, one transmission unit 1
The gear ratio of 5a and j _a, the other transmission unit 15b
If the speed ratio of the above is j _b , then the speed ratio of j _a × j _b can be obtained for the toroidal type continuously variable transmission as a whole.

In order to obtain a large gear ratio, the transmission unit 1
By providing two sets of 5a and 15b, it is inevitable that the transmission will be enlarged to some extent and the weight will be increased, but the weight is increased compared to the case where one toroidal transmission is enlarged to obtain a large gear ratio. Etc. are much less necessary.

In the illustrated embodiment, the rear (right side in FIG. 1) transmission unit 15b in the power transmission direction is formed larger than the front (left side in FIG. 1) transmission unit 15a. ing. This is because the torque input to the rear transmission unit 15b becomes larger than the torque input to the transmission unit 15a when the front transmission unit 15a is used in a decelerated state.

Next, FIG. 2 shows a second embodiment of the present invention. In the present embodiment, a pair of left and right drive shafts that are coupled to each other via a differential gear 20 by a first electric motor 17 energized by a solar cell and a second electric motor 18 energized by a battery. The present invention is applied to a power transmission device for a so-called hybrid electric vehicle that drives 19 and 19 to rotate. This toroidal type continuously variable transmission has first and second transmission units 21 and 22 which are coupled to each other in series.

The driving force of the first electric motor 17 is transmitted to the input side disc 25a of the first transmission unit 21 via the gears 23 and 24 meshing with each other, and the input side disc 25a is rotated. . The rotation of the input side disk 25a is performed by the power rollers 8 and 8 and the output side disk 26a through the cam plate 10a which constitutes the pressurizing device 9a.
And the cam plate 10a is rotated.

The other end of the connecting shaft 27, one end of which is fixed to the cam plate 10a, is fixed to the cam plate 10b which constitutes the pressurizing device 9b incorporated in the second transmission unit 22. Therefore, in synchronization with the rotation of the output side disk 26a of the first transmission unit 21, the input side disk 25b of the second transmission unit 22 is rotationally driven via the pressurizing device 9b.

The rotation of the input side disk 25b of the second transmission unit 22 is transmitted to the output side disk 26b via the power rollers 8 and 8, and the output side disk 2b is transmitted.
Rotate 6b. The configuration up to this point is basically the same as that of the first embodiment described above, although there are some differences in the arrangement of the first and second transmission units 21 and 22.

Particularly, in the present embodiment, the connecting shaft 2 is
The other end of 7 is connected to the second electric motor 18 and can be rotationally driven by the second electric motor 18.
Therefore, the input side disk 25b of the second transmission unit 22 has the driving force transmitted from the first electric motor 17 via the first transmission unit 21 and the second electric motor 18 It is rotationally driven by the sum of the driving force of

Further, the rotation of the second transmission unit 22 is transmitted to the differential gear 20 via a gear speed reducer 32 composed of a plurality of gears 28 to 31, and is transmitted via the differential gear 20. , The above 1
The pair of drive shafts 19, 19 are rotationally driven.

In the case of this embodiment configured as described above, the rotational driving force of the first electric motor 17 is generated by the first transmission unit 21, the second transmission unit 22, and the gear reducer 32. And 1 via the differential gear 20
The drive shafts 19 and 19 are transmitted to the pair of drive shafts 19 and 19.
The pair of left and right drive wheels, which are provided at the ends of the, are rotationally driven.

When the rotational driving force of the first electric motor 17 is insufficient for the driving force of the driving wheels due to a small amount of power generated by the solar cell, the second electric motor 18 is energized from the battery. To do. This second electric motor 18
The input side disk 25b of the second transmission unit 22 is driven not only by the rotational driving force of the first electric motor 17 but also by the rotational driving force of the second electric motor 18 in accordance with the energization of Is rotated. As a result, the force (torque) for rotating the input side disk 25b of the second transmission unit 22 becomes sufficiently large.

In this way, both the first and second electric motors 1
When the single input side disk 25b is rotated by 7, 18, both electric motors 17, 1 are used to suppress power loss.
It is necessary to match the rotational speed of the power transmitted from 8 to the input side disk 25b. On the other hand, it is difficult to arbitrarily adjust the rotation speed of the first electric motor 17, which is rotated by energization from the solar cell.

Therefore, in the case of this embodiment, the first transmission unit 21 is adjusted by adjusting the inclination angles of the power rollers 8, 8 constituting the first transmission unit 21.
The rotation speed of the output side disk 26a and the rotation speed of the second electric motor 18 are matched. As a result, the rotational speeds of the power transmitted from the two systems from the first and second electric motors 17 and 18 to the single input side disk 25b match, and the power loss is suppressed.

Although not shown, an electromagnetic clutch is incorporated in the first and second electric motors 17 and 18 as needed, and when either of the electric motors is not energized, the corresponding electric motor is supported. The electromagnetic clutch is disconnected (disconnected) to prevent the electric motor from consuming the driving force. Also in the case of the present embodiment, as in the case of the first embodiment, the sizes of the first and second transmission units 21 and 22 are changed (the second transmission unit 22 is made larger). May be. Further, it is possible to energize the first electric motor 17 from the battery and energize the second electric motor 18 from the solar cell.

[0033]

Since the toroidal type continuously variable transmission of the present invention is constructed and operates as described above, by increasing the degree of freedom of the obtained gear ratio, the practicality of the toroidal type continuously variable transmission can be improved. Industrial effects are great, such as increasing convenience and contributing to practical application of hybrid electric vehicles.

[Brief description of drawings]

FIG. 1 is a side view showing a first embodiment of the present invention.

FIG. 2 is a schematic sectional view showing the second embodiment.

FIG. 3 is a side view showing a basic configuration of a conventionally known toroidal type continuously variable transmission in a state of maximum deceleration.

FIG. 4 is a side view showing the same state at the time of maximum acceleration.

[Explanation of symbols]

 1 Input Shaft 2 Input Side Disk 2a Inner Side Surface 3 Output Shaft 4 Output Side Disk 4a Inner Side Surface 5 Axis 6 Trunnion 7 Displacement Axis 8 Power Roller 8a Circumferential Surface 9, 9a, 9b Pressurizing Device 10, 10a, 10b Cam Plate 11 Holding Device 12 Rollers 13 and 14 Cam surfaces 15a and 15b Transmission unit 16 Connection shaft 17 First electric motor 18 Second electric motor 19 Drive shaft 20 Differential gear 21 First transmission unit 22 Second transmission unit 23 , 24 gears 25a, 25b input side discs 26a, 26b output side disc 27 connecting shafts 28, 29, 30, 31 gears 32 gear reduction gears

Claims (1)

[Claims] 1. An input side disc, an output side disc concentrically arranged with respect to the input side disc, and rotatably supported with respect to the input side disc, and central axes of both the input side disc and the output side disc. The trunnion in a twisted position with respect to each other and swinging about a pair of concentric pivots, the displacement shaft supported by the trunnion, and the displacement shaft rotatably supported by both the input side and the output side. With a power roller sandwiched between the disks, the inner surfaces of the input side and output side disks facing each other are concave surfaces each having an arc-shaped cross section, and the peripheral surface of the power roller is a spherical convex surface. Two sets of transmission units formed by abutting the peripheral surface and the inner side surface are arranged in series with each other, and an output side disc of one transmission unit and an input side disc of the other transmission unit. A toroidal-type continuously variable transmission that is configured to be synchronously and rotatably coupled.