JP7486341B2 - Toroidal Continuously Variable Transmission - Google Patents

Description

The present invention relates to a toroidal continuously variable transmission.

Conventionally, toroidal continuously variable transmissions used in automobiles, aircraft generators, and the like are known. A toroidal continuously variable transmission includes an input disk, an output disk, and a power roller sandwiched between these disks. Power is transmitted from the input disk to the output disk as the power roller rotates. At that time, the output can be continuously decelerated or accelerated by changing the inclination of the power roller (i.e., changing the contact radius between the input disk and the output disk). Some toroidal continuously variable transmissions are provided with a loading cam type pressing device to bias the input disk and the output disk in a direction to approach each other. Patent Document 1 discloses this type of toroidal continuously variable transmission.

In the toroidal variable-speed transmission of Patent Document 1, a loading cam type pressing device (pressurizing device) is provided between the input disc and the input shaft. This pressing device includes a cam plate that rotates with the input shaft, and multiple rollers sandwiched between the input disc and the cam plate. The opposing surfaces of the input disc and the cam plate form a cam surface with unevenness in the circumferential direction. When the cam plate rotates in conjunction with the rotation of the input shaft, the unevenness of the cam surface acts on the multiple rollers, causing the input disc to rotate while being pressed against the power rollers. In this pressing device, a preload spring that presses the input disc toward the output disc is disposed between the input disc and the cam plate, and multiple rollers are disposed radially inward of the preload spring.

Japanese Utility Model Application Publication No. 6-1894

In the pressing device of the toroidal continuously variable transmission of Patent Document 1, the preload spring is disposed radially outward of the multiple rollers, so the input disk and the cam plate have approximately the same radius in order to compress the preload spring between them. This makes it difficult to reduce the radial dimension of the pressing device, including the cam plate.

This invention proposes a technology to further reduce the size of a pressing device in a toroidal continuously variable transmission equipped with a loading cam type pressing device.

A toroidal continuously variable transmission according to one embodiment of the present disclosure includes:
A rotation axis;
a first disk supported on the rotary shaft so as to be non-rotatable relative to the rotary shaft;
a second disk disposed opposite to the first disk and supported on the rotating shaft so as to be relatively rotatable;
a power roller tiltably sandwiched between the first disk and the second disk;
a preload spring that preloads the first disc toward the second disc;
a loading cam type pressing device that presses the first disk toward the second disk,
the pressing device includes a cam plate disposed opposite a rear surface of the first disc, a plurality of rollers sandwiched between the first disc and the cam plate, and a thrust bearing disposed on the rear surface side of the cam plate to support the cam plate so as to be rotatable relative to the rotary shaft;
the first disk has a cam surface on a radially inner portion of the back surface;
the rollers are disposed radially inward from an outer circumferential edge of the cam surface,
the preload spring is disposed between the cam plate and the thrust bearing, and radially inward of an outer circumferential edge of the cam surface ,
The cam plate has a cylindrical shaft portion that protrudes from its rear surface in parallel with the rotation axis of the rotary shaft, and external teeth are formed on the outer circumferential surface of the cylindrical shaft portion .

In the transmission with the above configuration, the rollers and preload spring are positioned radially inward (i.e., near the rotation axis) of the outer periphery of the cam surface formed on the first disk. By positioning the rollers and preload spring in this manner, it is possible to reduce the radius of the cam plate to the same as the radius of the outer periphery of the cam surface. In this way, the diameter of the cam plate and preload spring can be reduced, which allows the pressing device to be made smaller and lighter.

Furthermore, in the transmission with the above configuration, the components of the pressing device are concentrated around the rotation axis, so that the amount of eccentricity of the center of gravity of the pressing device from the rotation axis can be reduced. This makes it possible to reduce the unbalanced load during rotation caused by the eccentricity of the pressing device.

According to the present invention, it is possible to further reduce the size of a pressing device in a toroidal continuously variable transmission equipped with a loading cam type pressing device.

FIG. 1 is a cross-sectional view of a drive mechanism-integrated power generating device including a toroidal continuously variable transmission according to one embodiment of the present invention. FIG. 2 is an enlarged view of the pressing device of the toroidal continuously variable transmission shown in FIG. 1 and its vicinity. FIG. 3 is a schematic diagram of the cam plate and the output disk as viewed from the axial direction.

The following describes the embodiment with reference to the drawings.

Figure 1 is a cross-sectional view of a drive mechanism integrated generator 1 equipped with a toroidal continuously variable transmission 10 according to this embodiment. As shown in Figure 1, the drive mechanism integrated generator 1 (Integrated Drive Generator: IDG) is used as an AC power source for aircraft and is equipped with a casing 2 that is attached to the aircraft engine. The casing 2 houses an input mechanism 3, a toroidal continuously variable transmission (hereinafter simply referred to as "transmission 10"), a power transmission mechanism 7, and a generator 5. Note that the transmission 10 does not have to be configured as part of the drive mechanism integrated generator, and its use is not limited to aircraft.

[General configuration of the transmission 10]
The transmission 10 includes a transmission input shaft 11 and a transmission output shaft 12 that are coaxially arranged and can rotate relative to each other. Hereinafter, the axes of the transmission input shaft 11 and the transmission output shaft 12 are referred to as the "rotation axis A1". The extending direction of the rotation axis A1 is referred to as the "axial direction X". The transmission input shaft 11 is connected to an engine rotating shaft (not shown) via an input mechanism 3. The input mechanism 3 includes a device input shaft 3a to which rotational power from the engine rotating shaft is input, and a gear 3b that rotates integrally with the device input shaft 3a. The transmission input shaft 11 is provided with a gear 6 that rotates integrally therewith. The transmission output shaft 12 is connected to a generator input shaft 5a of the generator 5 via a power transmission mechanism 7.

The rotational power extracted from the engine rotating shaft is input to the transmission input shaft 11 via the input mechanism 3, and the rotational power of the transmission input shaft 11 is transmitted to the input disk 13. The transmission 10 changes the speed of the rotation of the transmission input shaft 11 and outputs it to the transmission output shaft 12. The rotational power of the transmission output shaft 12 is transmitted to the generator input shaft 5a via the power transmission mechanism 7. When the generator input shaft 5a is driven to rotate, the generator 5 generates AC power. The gear ratio of the transmission 10 is continuously changed so as to maintain the rotational speed of the generator input shaft 5a at an appropriate value (a value corresponding to a frequency suitable for the operation of the aircraft's electrical equipment) regardless of fluctuations in the rotational speed of the engine rotating shaft.

As an example, the transmission 10 is a half-toroidal type and a double cavity type, and has two sets of input discs 13, 13 and output discs 14, 15. However, the transmission 10 is not limited to the double cavity type, and may be, for example, a single cavity type.

The input discs 13, 13 are fitted to the transmission input shaft 11 and rotate integrally with the transmission input shaft 11 around the rotation axis A1. The output discs 14, 15 are spline-fitted to the transmission output shaft 12 and rotate integrally with the transmission output shaft 12 around the rotation axis A1.

The input disk 13 has a concave surface 21a. The output disks 14 and 15 have concave surfaces 31a. The input disk 13 and the output disk 14 are arranged facing each other in the axial direction X so that their concave surfaces 21a and 31a face each other. Similarly, the input disk 13 and the output disk 15 are arranged facing each other in the axial direction X so that their concave surfaces 21a and 31a face each other. The opposing concave surfaces 21a and 31a form an annular cavity around the rotation axis A1.

The transmission 10 is, as an example, a central input type. The transmission output shaft 12 is inserted into the transmission input shaft 11 and protrudes from the transmission input shaft 11 on both sides in the axial direction X. The pair of input disks 13, 13 are central disks and are arranged back-to-back on the transmission input shaft 11. The pair of output disks 14, 15 are outer disks and are arranged outside the pair of input disks 13, 13 in the axial direction X. A gear 6 is arranged between the pair of input disks 13, 13 on the outer circumferential surface of the transmission input shaft 11 and rotates integrally with the transmission input shaft 11.

The output disk 14 on one side is restricted from being displaced outward from the rotation axis A1 by a protrusion 12a provided at the end of the transmission output shaft 12. The output disk 15 on the other side is biased toward the input disk 13 by a preload spring 64, and is biased toward the input disk 13 by a pressing device 17 during rotational driving. The output disk 15 is connected to the power transmission mechanism 7 via the pressing device 17 so that power can be transmitted. The pressing device 17 will be described in detail later.

The transmission 10 includes a plurality of power rollers 18 arranged in a cavity, and a plurality of trunnions 19 that support the plurality of power rollers 18 so that they can be tilted. The trunnions 19 are supported by the casing 2 in a state in which they can be tilted around the tilt axis A2 and displaced in the direction of the tilt axis A2. The tilt axis A2 is in a twisted position with respect to the rotation axis A1. The power rollers 18 are supported by the trunnions 19 so that they can rotate freely around a rotation axis (not shown) perpendicular to the tilt axis A2. The trunnions 19 are connected to a hydraulic drive mechanism (not shown), which reciprocates the trunnions 19 together with the power rollers 18 in the direction of the tilt axis A2.

[Configuration of the pressing device 17]
Fig. 2 is an enlarged view of the pressing device 17 and its vicinity of the toroidal continuously variable transmission 10 shown in Fig. 1. As shown in Fig. 2, the pressing device 17 includes a cam plate 61, a roller unit 60, and a thrust bearing 65.

The cam plate 61 is loosely fitted to the transmission output shaft 12 so as to face the rear surface of the output disk 15 (the surface opposite the concave surface 31a). The cam plate 61 integrally has a hollow disk-shaped cam portion 611 and a cylindrical shaft portion 612 that protrudes from the outer periphery of the cam portion 611 in the axial direction X.

The main surface of the cam portion 611 faces the back surface of the output disk 15. The main surface of the cam portion 611 is a first cam surface 613. The first cam surface 613 has repeated projections and recesses formed in the circumferential direction. A second cam surface 151 is provided on the back surface of the output disk 15 facing the first cam surface 613. The second cam surface 151 also has repeated projections and recesses formed in the circumferential direction to correspond to the first cam surface 613.

The second cam surface 151 is provided on the radially inner portion 15a of the back surface of the output disk 15. In this specification, "radial direction" is defined as the radial direction (radiating direction) centered on the rotation axis A1. "Radially inner side" is defined as the side radially toward the rotation axis A1 based on a certain location. Also, "radially outer side" is defined as the side radially away from the rotation axis A1 based on a certain location. Also, "radius" is the radius of the rotating body centered on the rotation axis A1, and the distance from the rotation axis A1.

The back surface of the output disk 15 is divided into a radial inner portion 15a and a radial outer portion 15b. The radius Br of the boundary B between the radial inner portion 15a and the radial outer portion 15b is smaller than the radius Dr of the output disk 15. The radius Br of the boundary B is larger than the length of the roller set 63G in the direction of the rotation axis, which will be described later, including the retainer 62 that holds it. The dimension of the roller set 63G in the direction of the rotation axis can be determined based on the load received by the roller set 63G and the cam surfaces 151 and 613. The relationship between the radius Br of the boundary B and the radius Dr of the output disk 15 may be specified as (2/3 x Dr) ≦ Br < Dr, or (1/2 x Dr) ≦ Br < Dr, for example.

The second cam surface 151 provided on the output disk 15 may be distinguished in appearance from the radially outer portion 15b by forming unevenness on the radially inner portion 15a of the output disk 15. However, unevenness may be provided over the entire back surface of the output disk 15 for manufacturing reasons. In this case, the radially inner portion 15a of the back surface of the output disk 15, which is a portion that overlaps with the roller unit 60 in the axial direction X, or a portion on which the peripheral surfaces of the multiple rollers 63 held by the roller unit 60 roll, may be regarded as the second cam surface 151.

The roller unit 60 is provided between the first cam surface 613, the second cam surface 151, and the axial direction X. The roller unit 60 is composed of a holder 62 and a plurality of rollers 63 held by the holder 62. Each roller 63 is sandwiched between the first cam surface 613 and the second cam surface 151, and its peripheral surface is in contact with both the first cam surface 613 and the second cam surface 151.

The cage 62 holds multiple roller sets 63G arranged at approximately equal intervals in the circumferential direction around the rotation axis A1. Each roller set 63G includes at least one roller 63 (three in this embodiment) arranged on a rotation axis extending in the radial direction. Each roller 63 of the roller set 63G is rotatable around the rotation axis of the roller set 63G.

The rollers 63 are arranged radially inward from the outer periphery (i.e., boundary B) of the cam surface 151 of the output disc 15. In other words, the rollers 63 are arranged in a concentrated manner near the transmission output shaft 12, radially inward from the outer periphery of the output disc 15. The middle of both radial ends of the roller set 63G is referred to as the "roller set intermediate portion 63C." It is desirable that the radius 63r of the roller set intermediate portion 63C (i.e., the radial distance from the rotation axis A1 to the roller set intermediate portion 63C) is equal to or smaller than half the radius Dr of the output disc 15.

The thrust bearing 65 is disposed on the rear side of the cam plate 61 (i.e., the side opposite the cam portion 611) and supports the cam plate 61 so as to be rotatable relative to the transmission output shaft 12. Specifically, the thrust bearing 65 has an inner ring 651, an outer ring 652, and a rolling element 653 rotatably sandwiched between the inner ring 651 and the outer ring 652. The inner ring 651 is fixed to the transmission output shaft 12 by a fastener (not shown). The outer ring 652 is rotatable relative to the inner ring 651, and rotates integrally with the cam plate 61 about the rotation axis A1.

A preload spring 64 is disposed between the cam plate 61 and the thrust bearing 65. In other words, the rollers 63 and the preload spring 64 are aligned in the axial direction X via the cam plate 61. The preload spring 64 applies a pressing force to the cam plate 61 in the axial direction X toward the output disk 15 so that the output disk 15 is pressed (preloaded) toward the input disk 13 even when the transmission output shaft 12 is not rotating. The preload spring 64 in this embodiment is sandwiched between the cam portion 611 of the cam plate 61 and the outer ring 652 of the thrust bearing 65 and compressed in the axial direction X.

The preload spring 64 is disposed radially inward from the outer periphery (i.e., boundary B) of the cam surface 151 of the output disc 15. In other words, the preload spring 64 is disposed radially inward from the outer periphery of the output disc 15, in the vicinity of the transmission output shaft 12. The preload spring 64 is accommodated in the annular space between the cylindrical shaft portion 612 of the cam plate 61 and the outer periphery of the transmission output shaft 12. In this embodiment, the preload spring 64 is a disc spring loosely fitted on the transmission output shaft 12.

Figure 3 is a schematic diagram of the cam plate 61 and the output disk 15 viewed from the axial direction X. As shown in Figure 3, the range (range 63A) in which the rollers 63 roll on the cam plate 61 is roughly hollow and disk-shaped when viewed parallel to the rotation axis A1. The range (range 64A) in which the most compressed preload spring 64 contacts the back surface of the cam plate 61 is roughly hollow and disk-shaped when viewed parallel to the rotation axis A1. At least a portion of range 64A overlaps with range 63A when viewed parallel to the rotation axis A1. In this way, the preload spring 64 is arranged on the extension line of the rollers 63 extended parallel to the rotation axis A1 of the transmission output shaft 12.

Returning to FIG. 2, the outer ring 652 of the thrust bearing 65 has a spring abutment portion 65a and a stopper portion 65b located radially outward of the spring abutment portion 65a. In this embodiment, the spring abutment portion 65a is located radially inward of the cylindrical shaft portion 612 and abuts against the preload spring 64. In this embodiment, a shim plate 66 is provided as an adjustment member between the spring abutment portion 65a and the preload spring 64, and more specifically, the spring abutment portion 65a abuts against the shim plate 66. The shim plate 66 may be provided between the cam plate 61 and the preload spring 64. The preload spring 64, the cam plate 61, the roller set 63G, and the output disk 15 are located on the extension line of the spring abutment portion 65a in the axial direction X.

The stopper portion 65b faces the cylindrical shaft portion 612 of the cam plate 61 in the axial direction X with a small gap G between them. In this embodiment, the cylindrical shaft portion 612 of the cam plate 61, the roller set 63G, and the output disk 15 are located on the extension line of the stopper portion 65b in the axial direction X.

When the cam plate 61 is not rotating, the length of the gap G in the axial direction X is smaller than the amount of deformation in the axial direction X at the elastic limit of the preload spring 64. Therefore, when the cam plate 61 rotates and the output disk 15 and the cam plate 61 begin to move relative to each other in the axial direction X due to the cam action, the cam plate 61 hits the stopper portion 65b while the preload spring 64 is within the elastic deformation range, and the gap G disappears. After the cam plate 61 hits the stopper portion 65b, the pressing force on the output disk 15 due to the cam action increases with the increase in the transmission torque. In this way, the output disk 15 is pressed away from the cam plate 61 by the cam action with the increase in the transmission torque, so that the input disk 13 and the output disk 15 are urged in a direction to approach each other, and the power roller 18 is sandwiched between the input disk 13 and the output disk 15 with sufficient contact pressure.

When the gap G remains, the radially inner portion of the cam plate 61 is supported in the axial direction X by the thrust bearing 65. When the gap G disappears, the radially inner portion and the radially outer portion of the cam plate 61 are supported in the axial direction X by the thrust bearing 65. In this way, by supporting the cam plate 61 in the axial direction X at both the radially inner portion and the radially outer portion during high speed rotation of the cam plate 61, the load applied from the roller 63 to the cam surfaces 151, 613 is distributed equally in the radial direction. This makes it possible to suppress fretting wear of the cam surfaces 151, 613.

External teeth 614 are formed on the outer circumferential surface of the cylindrical shaft portion 612 of the cam plate 61. These external teeth 614 mesh with internal teeth 711 provided on the first gear 71 of the power transmission mechanism 7 to form a dog clutch. When the cam plate 61 receives a rotational force from the output disk 15 via a plurality of rollers 63 and rotates, the rotation of the cam plate 61 is transmitted to the first gear 71 of the power transmission mechanism 7. The power transmission mechanism 7 transmits the output from the transmission 10 to the generator 5 and the oil pump unit (not shown).

[Configuration of power transmission mechanism 7]
1, the power transmission mechanism 7 is composed of a plurality of gears including a first gear 71 to a fourth gear 74. The first gear 71 is a hollow gear. The first gear 71 has internal teeth 711 and external teeth 712. The internal teeth 711 mesh with the external teeth 614 of the cam plate 61, and the external teeth 712 mesh with the second gear 72.

The second gear 72 has main teeth 721 and secondary teeth 722. The main teeth 721 mesh with the external teeth 712 of the first gear 71 and the third gear 73. The secondary teeth 722 mesh with a gear (not shown) for transmitting the output of the transmission 10 to an oil pump unit (not shown). The third gear 73 meshes with the main teeth 721 of the second gear 72 and the fourth gear 74. The fourth gear 74 is fixed to the generator input shaft 5a of the generator 5.

As described above, the cam plate 61 and roller unit 60, which are components of the pressing device 17, and the preload spring 64 are concentrated near the transmission output shaft 12, making it possible to place the first gear 71 on the outer periphery of the pressing device 17. In this embodiment, the transmission output shaft 12, cam plate 61, preload spring 64, and thrust bearing 65 are placed in a cylindrical space formed by the boss of the first gear 71. In other words, the axial X positions of the cam plate 61, preload spring 64, and thrust bearing 65 overlap with the axial X position of at least a portion of the first gear 71. This makes it possible to reduce the axial X dimension including the transmission 10 and the power transmission mechanism 7.

Operation of the Transmission 10
In the transmission 10 configured as described above, when the input disks 13, 13 are rotationally driven, the output disks 14, 15 are rotationally driven via the power rollers 18, and the transmission output shaft 12 is rotationally driven. When the trunnions 19 and the power rollers 18 are displaced in the direction of the tilt axis A2, the tilt angle of the power rollers 18 about the tilt axis A2 is changed, and the speed ratio of the transmission 10 is continuously changed according to the tilt angle. The power rollers 18 are sandwiched between the concave surfaces 21a of the input disks 13, 13 and the concave surfaces 31a of the output disks 14, 15 in a state in which they can tilt about the tilt axis A2, and transmit the rotational driving force of the input disk 13 to the output disks 14, 15 at a speed change ratio according to the tilt angle. When the rotational torque of the output disks 14, 15 increases, the pressing device 17 presses the output disk 15 in a direction approaching the input disk 13, and the pressure with which the input disks 13, 13 and the output disks 14, 15 pinch the power rollers 18 increases.

When the output disk 15 rotates, the cam surface 151 presses the rollers 63 against the cam surface 613 of the cam plate 61. As a result, the output disk 15 is pressed against the power roller 18, and at the same time, the cam plate 61 rotates based on the meshing of the pair of cam surfaces 151, 613 with the rollers 63. The rotation of the cam plate 61 is then input to the power transmission mechanism 7 by the meshing of the dog clutch (external teeth 614 of the cam plate 61 and internal teeth 711 of the first gear 71), causing the generator input shaft 5a to rotate.

As described above, the transmission 10 according to this embodiment includes the transmission output shaft 12 (rotating shaft), the output disk 15 (first disk) supported on the transmission output shaft 12 so as not to rotate relative to the output disk 15, the input disk 13 (second disk) arranged opposite the output disk 15 and supported on the transmission output shaft 12 so as to be rotatable relative to the output disk 15, the power roller 18 tiltably sandwiched between the output disk 15 and the input disk 13, the preload spring 64 that preloads the output disk 15 toward the input disk 13, and the loading cam type pressing device 17 that presses the output disk 15 toward the input disk 13. The pressing device 17 includes a cam plate 61 arranged opposite the back surface of the output disk 15, a plurality of rollers 63 sandwiched between the output disk 15 and the cam plate 61, and a thrust bearing 65 arranged on the back surface of the cam plate 61 to support the cam plate 61 so as to be rotatable relative to the rotating shaft. The output disk 15 has a cam surface 151 on the radially inner portion 15a of the back surface, and the rollers 63 are arranged radially inward from the outer periphery of the cam surface 613, and the preload spring 64 is arranged between the cam plate 61 and the thrust bearing 65, radially inward from the outer periphery of the cam surface 613.

In the transmission 10 having the above configuration, the rollers 63 and the preload spring 64 are arranged radially inward from the outer periphery of the cam surface 151 formed on the output disk 15, and more preferably in the vicinity of the transmission output shaft 12. For example, the radius 63r of the intermediate portion (i.e., the roller set intermediate portion 63C) of both radial ends of the combination of the rollers 63 may be less than half the radius Dr of the output disk 15. By arranging the rollers 63 and the preload spring 64 in this manner, it is possible to reduce the radius of the cam plate 61 to the same as the radius of the outer periphery of the cam surface 151. In the transmission 10 according to this embodiment, the radius of the cam plate 61 is the same as or smaller than the radius of the cam surface 151 of the output disk 15 (first disk). Similarly, it is possible to make the radius of the retainer 62 that holds the rollers 63 smaller than the radius of the output disk 15. In this way, the diameter of the cam plate 61 and preload spring 64 (as well as the retainer 62) can be reduced, making the pressing device 17 lighter.

The radially inner portion 15a of the output disk 15 is less deformed than the radially outer portion 15b. The provision of the cam surface 151 on the radially inner portion 15a of the output disk 15 suppresses the occurrence of slippage of the rollers 63 on the cam surfaces 151, 613 caused by deformation of the output disk 15. This makes it possible to suppress fretting wear of the cam surfaces 151, 613.

The roller unit 60, which is made up of multiple rollers 63 and a retainer 62 that holds them, is loosely fitted onto the transmission output shaft 12, with gaps between the rollers 63. The pressing device 17, which is made up of fitting members arranged with gaps, is prone to fluctuations in center of gravity. In contrast, in this embodiment, the components of the pressing device 17 are concentrated around the rotation axis A1, which makes it possible to reduce the amount of eccentricity of the center of gravity of the pressing device 17 from the rotation axis A1. This makes it possible to reduce the unbalanced load during rotation caused by the eccentricity of the pressing device 17.

In the transmission 10 according to this embodiment, the cam plate 61 has a cylindrical shaft portion 612 that protrudes parallel to the rotation axis A1 toward the thrust bearing 65, and a preload spring 64 is disposed radially inside the cylindrical shaft portion 612. When the transmission output shaft 12 (rotary shaft) is not rotating, a gap G is formed between the end of the cylindrical shaft portion and the thrust bearing by the preload spring 64 compressed between the cam plate 61 and the thrust bearing 65.

According to the above configuration, when the transmission output shaft 12 is not rotating (and under low load), the gap G is maintained by the preload spring 64, and the cam plate 61 is supported by the thrust bearing 65 via the preload spring 64. When the transmission torque increases due to an increase in the power generation load, the preload spring 64 is further compressed, the cylindrical shaft portion 612 abuts against the thrust bearing 65, and the cam plate 61 is supported by the thrust bearing 65 via the preload spring 64, and the cylindrical shaft portion 612 is also supported by the thrust bearing 65. The preload spring 64 and the cylindrical shaft portion 612 are radially separated. In this way, when the transmission torque increases, the cam plate 61 is supported in a dispersed manner at several points radially separated, so that the load applied from the multiple rollers 63 to the cam surface 151 of the output disk 15 and the cam surface 613 of the cam plate 61 can be made uniform, and the occurrence of fretting wear can be suppressed.

In addition, in the transmission 10 according to this embodiment, the cam plate 61 has a cylindrical shaft portion 612 that protrudes from its back surface in parallel with the rotation axis A1, and external teeth 614 are formed on the outer circumferential surface of the cylindrical shaft portion 612.

With the above configuration, a gear (first gear 71) for extracting power from the cam plate 61 can be arranged on the outer periphery of the cam plate 61. In other words, the cam plate 61 and the first gear 71 can be arranged to overlap in the axial direction X. This makes it possible to shorten the length in the axial direction X of the transmission 10 and the mechanism for extracting power from it (the power transmission mechanism 7 in this embodiment).

The above describes a preferred embodiment of the present invention, but the present invention also includes modifications of the specific structure and/or function details of the above embodiment without departing from the spirit of the present invention. The above configuration can be modified as follows:

For example, the transmission 10 is not limited to a central input type, and may be a central output type. In the case of a central output type, the positional relationship between the input disk 13 and the output disk 14 described above is reversed, with the output disk becoming the central disk (second disk) and the input disk becoming the outer disk (first disk). In this case, the pressing device 17 is configured to press the input disk toward the output disk, and rotation is input to the cam plate 61 from a gear that meshes with the external teeth 614.

1: Drive mechanism integrated power generation device 10: Toroidal continuously variable transmission 11: Transmission input shaft 12: Transmission output shaft (an example of a rotating shaft)
13: Input disk (an example of the second disk)
14, 15: Output disk (an example of the first disk)
15a: Radial inner portion 17: Pressing device 18: Power roller 61: Cam plate 63: Roller 64: Preload spring 65: Thrust bearing 151: Cam surface 612: Cylinder shaft portion 613: Cam surface 614: External teeth A1: Rotation axis G: Gap

Claims (4)

A rotation axis;
a first disk supported on the rotary shaft so as to be non-rotatable relative to the rotary shaft;
a second disk disposed opposite to the first disk and supported on the rotating shaft so as to be relatively rotatable;
a power roller tiltably sandwiched between the first disk and the second disk;
a preload spring that preloads the first disc toward the second disc;
a loading cam type pressing device that presses the first disk toward the second disk,
the pressing device includes a cam plate disposed opposite a rear surface of the first disc, a plurality of rollers sandwiched between the first disc and the cam plate, and a thrust bearing disposed on the rear surface side of the cam plate to support the cam plate so as to be rotatable relative to the rotary shaft;
the first disk has a cam surface on a radially inner portion of the back surface;
the rollers are disposed radially inward from an outer circumferential edge of the cam surface,
the preload spring is disposed between the cam plate and the thrust bearing, and radially inward of an outer circumferential edge of the cam surface ,
The cam plate has a cylindrical shaft portion protruding from its back surface in parallel with the rotation axis of the rotary shaft, and external teeth are formed on the outer peripheral surface of the cylindrical shaft portion .
Toroidal continuously variable transmission. the radius of the cam plate is equal to or smaller than the radius of the cam surface of the first disk;
2. The toroidal continuously variable transmission according to claim 1. The preload spring is disposed radially inside the cylindrical shaft portion,
When the rotating shaft is not rotating, a gap is formed between the end of the cylindrical shaft portion and the thrust bearing by the preload spring compressed between the cam plate and the thrust bearing.
3. The toroidal continuously variable transmission according to claim 1 or 2. A radius of a middle portion of both radial ends of the combination of the plurality of rollers is half or less of a radius of the first disk.
The toroidal continuously variable transmission according to any one of claims 1 to 3 .

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