JP2015224667A - Toroidal continuously variable transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a structure capable of being configured small in size, light in weight, and simply while preventing the occurrence of gross slip.SOLUTION: A pair of output-side discs 16a and 16b is supported around two end portions of a rotary shaft that serves as an output shaft so as to be rotatable synchronously with the rotary shaft. Furthermore, a pair of input-side discs 17 is supported around an intermediate portion of the rotary shaft so as to be relatively rotatable to the rotary shaft. Of the two output-side discs 16a and 16b, the output-side disc 16b opposite to a side on which a pressing device is provided is set to have a thickness (T) near an outside diameter in an axial direction smaller than a thickness (T) near the outside diameter in the axial direction of the output-side disc 16a on the side on which the pressing device is provided (T<T).

Description

  The present invention relates to an improvement of a toroidal continuously variable transmission that is used as an automatic transmission for a generator (alternator, generator) used in an aircraft (fixed wing aircraft, rotary wing aircraft, airship, etc.), for example. .

  A generator used in an aircraft or the like needs to be driven to rotate at a constant rotational speed regardless of the rotational speed of the engine. For this reason, an automatic transmission is incorporated between the input shaft of the generator and the output shaft of the engine. As such an automatic transmission, if a continuously variable transmission configured with a continuously variable transmission mechanism capable of adjusting the transmission ratio steplessly is adopted, even if the engine rotational speed fluctuates, the input shaft of the generator Can be stably rotated at a constant rotational speed. 5 to 6 show a first example of a conventional structure of a toroidal type continuously variable transmission that can be used as such a continuously variable transmission. In the case of the first example of this conventional structure, a pair of outer disks 2a and 2b are disposed around both ends of the rotating shaft 1, and the ball splines 3 and 3 are placed in a state where the inner side surfaces, which are toroidal curved surfaces, face each other. The cylindrical member 4 is supported around the intermediate portion of the rotary shaft 1 so as to be capable of relative rotation with respect to the rotary shaft 1. Further, a gear 5 is fixed to the outer peripheral surface of the cylindrical member 4 at the center in the axial direction, and a pair of inner disks 6 and 6 are attached to both ends of the axial direction by spline engagement with the cylindrical member 4. Supports synchronized rotation. In this state, the inner side surfaces of the inner disks 6 and 6, each of which is a toroidal curved surface, are opposed to the inner side surfaces of the outer disks 2 a and 2 b.

  Further, a plurality of power rollers 7 and 7 each having a spherical convex surface are sandwiched between the outer disks 2a and 2b and the inner disks 6 and 6. The power rollers 7 and 7 are respectively connected to the inner surfaces of the trunnions 8 and 8 via support shafts 9 and 9 having a base half portion and a tip half portion eccentric, and a plurality of rolling bearings. , 9 and the rotation of the first half of the support shaft 9 and a slight swing displacement about the base half of each of the support shafts 9 and 9 are supported. The trunnions 8 and 8 are supported so as to be swingable and displaceable about the tilting shafts 10 and 10 that are twisted with respect to the central axes of the disks 2a, 2b, and 6, respectively.

During operation of the toroidal-type continuously variable transmission as described above, one of the outer disks 2a (left side in FIG. 5) is rotationally driven by the drive shaft 11 via the cam type pressing device 12. As a result, the pair of outer disks 2a and 2b supported at both axial ends of the rotary shaft 1 rotate in synchronization while being pressed in a direction approaching each other. Then, this rotation is transmitted to the inner disks 6 and 6 through the power rollers 7 and 7 and is taken out from the gear 5. When changing the gear ratio between the rotary shaft 1 and the gear 5, the trunnions 8 and 8 are displaced in the axial direction of the tilt shafts 10 and 10 by hydraulic actuators 13 and 13, respectively. As a result, the direction of the tangential force acting on the rolling contact portion (traction portion) between the peripheral surface of each of the power rollers 7 and 7 and the inner surface of each of the disks 2a, 2b and 6 changes (rolling contact). Side slip occurs in the part). As the force changes, the trunnions 8 and 8 swing around their own tilting shafts 10 and 10, and the peripheral surfaces of the power rollers 7 and 7 and the disks 2a, The contact position with the inner surface of 2b, 6 changes. The circumferential surface of each of these power rollers 7 and 7 is in rolling contact with the radially outward portion of the inner surface of the outer disks 2a and 2b and the radially inner portion of the inner surfaces of the inner disks 6 and 6. If it does so, the gear ratio between the said rotating shaft 1 and the said gearwheel 5 will become a speed-up side. On the other hand, the peripheral surfaces of the power rollers 7 and 7 are arranged radially inwardly on the inner side surfaces of the outer disks 2a and 2b and radially outer sides of the inner surfaces of the inner disks 6 and 6. If it is brought into rolling contact with the portion, the transmission gear ratio between the rotary shaft 1 and the gear 5 is reduced.
In the above description, the outer side disks 2a and 2b are used as input side disks, and the inner side disks 6 and 6 are used as output side disks. In addition, a structure in which the inner disk is used as an input disk is also known, for example, as described in Patent Document 1.

  In the case of the toroidal type continuously variable transmission having the conventional structure as described above, the pair of inner disks 6 and 6 and the gear 5 are separated, and at both ends of the cylindrical member 4 provided at the center of the gear 5, Both of these inner disks 6, 6 are in spline engagement. For this reason, it is inevitable that the number of parts increases and the axial dimensions of the installed portions of the inner disks 6 and 6 and the gear 5 increase. On the other hand, Patent Document 2 discloses a structure in which a toroidal continuously variable transmission can be reduced in size and weight by using an integral inner disk. Although FIG. 7 is not the structure described in the said patent document 2, like the structure described in this patent document 2, the toroidal type continuously variable transmission of the 2nd example of the conventional structure incorporating the integrated inner disk is shown. Showing the machine.

In the case of the second example of the conventional structure, the inner disk 6a having a structure in which the outer surfaces of the pair of inner disks 6, 6 shown in FIG. That is, the integral inner disk 6a is rotatably supported by a pair of radial needle bearings 14 and 14 around the intermediate portion of the rotating shaft 1a. A gear 15 which is a helical gear is provided on the outer peripheral surface of the inner disk 6a.
In the case of the illustrated example, in addition to the use of an integral type as the inner disk 6a, a hydraulic type is used as the pressing device 12a, the other of the rotation shaft 1a (the rotation shaft 1a). The outer disk 2b on the opposite side of the pressing device 12a on the opposite side of the pressing device 12a is supported by spline engagement. This is almost the same as the first example of the conventional structure shown in FIG.

  Regardless of the structure, there is room for improvement in terms of reduction in size and weight when used as a toroidal type continuously variable transmission incorporated in a generator such as an aircraft. That is, when the toroidal continuously variable transmission is operated, the respective disks 2a, 2b, 6, 6a are elastically deformed in the axial direction based on the axial force applied to the side surfaces of the respective disks 2a, 2b, 6, 6a. . The axial force applied to the side surfaces of each of the disks 2a, 2b, 6, 6a increases as the torque (transmission torque) transmitted by the toroidal-type continuously variable transmission increases, and accordingly, each member 2a, The amount of elastic deformation of 2b, 6, 6a and 7 also increases. FIG. 8 shows the relationship between the reduction ratio of the toroidal type continuously variable transmission, the input torque to the toroidal type continuously variable transmission, and the rotational speed (rotational speed) of each of the disks 2a, 2b, 6, 6a. ing. Here, in order to rotationally drive the input shaft of a generator such as an aircraft at a constant speed, the rotational speed of the rotary shafts 1 and 1a is constant regardless of the rotational speed of the inner disks 6 and 6a serving as input disks. Then, the transmission torque is proportional to the input torque of the toroidal type continuously variable transmission. Accordingly, when the rotational speed of the rotary shafts 1 and 1a is constant, the transmission torque reduces the reduction ratio between the inner disks 6 and 6a and the outer disks 2 and 2a serving as output side disks. It gets bigger. In a state where the reduction ratio is small (acceleration state), the radially outer portions of the inner side surfaces of the inner disks 6 and 6a and the peripheral surfaces of the power rollers 7 and 7 are in rolling contact. For this reason, in the case of a structure having a pair of inner disks 6 and 6 as in the first example of the conventional structure, the portions near the outer diameter of the inner disks 6 and 6a are easily elastically deformed in the axial direction. . In order to prevent the occurrence of excessive slip called gloss slip at the rolling contact portion between the inner side surfaces of the inner disks 6 and 6 and the peripheral surfaces of the power rollers 7 and 7 regardless of such elastic deformation. For this, it is necessary to increase the pressing amount (axial displacement amount) of one outer disk 2a of the outer disks 2a, 2b by the pressing device 12.

For example, when the pressing amount of the one outer disk 2a is increased by the cam-type pressing device 12, it is necessary to increase the inclination angle of the cam surface, the cam plate becomes thick, and the toroidal type continuously variable transmission. The machine becomes larger and heavier. Further, in the case of increasing the pressing amount (displacement amount of the hydraulic piston) of the one outer disk 2a with a hydraulic pressing device, it is necessary to increase the pump capacity. In this case, however, the oil pump is increased in size, and the power loss due to the oil pump increases, leading to a decrease in transmission efficiency.
Further, in both the first and second examples of the conventional structure, the thicknesses of the radially outer portions of the outer disks 2a and 2b are the same. For this reason, for example, when the reduction ratio between the inner disks 6 and 6a and the outer disks 2a and 2b is increased (deceleration state), the outer side on the side where the pressing devices 12 and 12a are disposed. There may be a difference in the amount of elastic deformation between the disk 2a and the outer disk 2b on the opposite side. Specifically, since the outer disk 2b disposed on the side opposite to the pressing devices 12 and 12a is not supported (backed up) by the pressing devices 12 and 12a, the elastic deformation amount of the outer disk 2b is This is larger than the elastic deformation amount of the outer disk 2a on the side where the pressing devices 12, 12a are arranged. For this reason, the pressing force between the inner surface of the outer disk 2b and the inner disks 6, 6a and the peripheral surfaces of the power rollers 7, 7 is reduced, and gloss slip is likely to occur. In order to prevent the occurrence of such gross slip, the pressing devices 12 and 12a may be enlarged as in the case of the elastic deformation of the inner disks 6 and 6 described above. It is not preferable from the viewpoint of miniaturization and weight reduction of the toroidal continuously variable transmission.

  On the other hand, in Patent Document 3, a toroidal continuously variable transmission and a planetary gear transmission are combined, and a part of the power is transmitted by bypassing the toroidal continuously variable transmission. Describes a structure capable of reducing the size and weight of the continuously variable transmission as a whole. However, in the case of the structure described in Patent Document 3, the structure becomes complicated, such as using a power diversion shaft to bypass part of the power to the toroidal continuously variable transmission. Further, in Patent Document 4, the thickness of the bottom of a pair of inner disks, which are output side disks that are freely supported relative to the rotation shaft around the middle portion of the rotation shaft, is indicated at both ends of the rotation shaft. Describes a structure that can be reduced in size and weight by making it smaller than the bottom wall thickness of a pair of outer disks, which is an input side disk that is supported so as to be able to rotate in synchronization with the rotating shaft. . However, even in the case of the structure described in Patent Document 4, there is room for further improvement in terms of reducing the size and weight of the toroidal continuously variable transmission.

JP 2011-153638 A Japanese Patent Laid-Open No. 2001-116097 Japanese Patent No. 3340287 Japanese Patent Laid-Open No. 2002-21969

  The present invention has been invented in order to realize the structure of a toroidal type continuously variable transmission that can be configured in a small size, light weight and simply in view of the circumstances as described above.

The toroidal continuously variable transmission of the present invention includes a rotating shaft, a pair of output side disks, an input side disk unit, a plurality of power rollers, and a pressing device.
A pair of the output side disks are supported so that they can rotate in synchronization with the rotating shaft at both ends of the rotating shaft, with the inner surfaces facing each other having arcuate cross sections. Has been.
In addition, the input side disk unit has the rotary shaft in a state where both side surfaces in the axial direction are opposed to the inner side surfaces of the two output side disks around the intermediate portion of the rotary shaft and between the two output side disks. Relative rotation with respect to is freely supported.
Each of the power rollers has a spherical convex surface, and the both outputs are in a state of rolling contact with the inner side surfaces of the two output side disks and the two axial side surfaces of the input side disk unit. It is rotatably supported by a portion between the inner side surface of the side disc and both side surfaces in the axial direction of the input side disc unit.
The pressing device is provided between the rotating shaft and one output side disk of the two output side disks, and the one output side disk is connected to the other of the two output side disks. Press toward the output disk.

  In particular, in the toroidal type continuously variable transmission according to the present invention, the thickness of the one output side disk near the outer diameter in the axial direction (for example, a cylinder portion of a hydraulic pressing device is formed). The thickness of the portion excluding the ridge and the cam surface constituting the cam type pressing device is made smaller than the thickness in the axial direction of the portion near the outer diameter of the other output side disk. That is, of the inner side surfaces of these two output side disks, the shaft of the outer diameter portion which is the portion where the peripheral surface of each power roller is in rolling contact when the transmission ratio of the toroidal type continuously variable transmission is in the maximum deceleration state The wall thickness in the direction is made smaller on one output side disk on the side where the pressing device is provided than on the other output side disk on the opposite side.

  When the toroidal continuously variable transmission of the present invention as described above is implemented, the input disk unit is preferably composed of a pair of input disk elements as in the invention described in claim 2. And the thickness in the axial direction of the portion near the outer diameter of the other output side disk, the portion near the outer diameter of these input side disk elements (with the transmission ratio of the toroidal type continuously variable transmission being the maximum speed increasing state, The thickness of each power roller is set to be smaller than the thickness in the axial direction of the portion where the periphery of the power roller is in rolling contact.

In addition, the toroidal continuously variable transmission of the present invention, for example, rotationally drives the rotating shaft as an output shaft at a constant speed regardless of the rotational speed of a driving source such as an engine that rotationally drives the input disk unit. It is used as an automatic transmission (except when this drive source is started and stopped).
Further, when the present invention is implemented, preferably, the pressing device is of a hydraulic type that presses the one output side disk toward the other output side disk as the hydraulic pressure is introduced into the hydraulic chamber. .

According to the toroidal type continuously variable transmission of the present invention configured as described above, it can be configured to be small, light, and simple.
That is, in the speed increasing state where the reduction ratio between the input side disk unit and the pair of output side disks is small and the transmission torque is large, the wall thickness in the axial direction is compared among the inner surfaces of these two output side disks. A portion closer to the inner diameter is in rolling contact with the peripheral surface of each power roller. On the other hand, in the deceleration state where the speed reduction ratio is large and the transmission torque is small, the outer diameter portion of the inner side surfaces of the two output-side disks that is relatively thin in the axial direction is the peripheral surface of each power roller. Rolling contact with. In particular, for the output side disk (one output side disk) on the side where the pressing device is provided, the axial force applied from each of the power rollers as the torque is transmitted is supported by the pressing device. For this reason, the thickness in the axial direction of the outer diameter portion of the other output side disk (the output side disk opposite to the side where the pressing device is provided) is set to the axis of the outer diameter portion of the one output side disk. By making it larger than the wall thickness in the direction, the amount of elastic deformation of the other output side disk can be suppressed. Therefore, it is possible to further reduce the size and weight of the toroidal continuously variable transmission while preventing the occurrence of gross slip. In the case of the present invention, since the toroidal continuously variable transmission is used alone without being combined with other transmissions such as a planetary gear type transmission, the structure is complicated as in Patent Document 2 described above. Rather, it can be configured simply.

  According to the second aspect of the present invention, the speed reduction state between the input side disk unit and the pair of output side disks is small and the transmission torque is large. Even when a portion closer to the outer diameter is in rolling contact with the peripheral surface of each power roller, the amount of elastic deformation of both the input side disk elements can be suppressed. For this reason, it is possible to suppress the pressing amount of the one output side disk by the pressing device while preventing the occurrence of the gross slip, and to reduce the size and weight of the toroidal continuously variable transmission. Accordingly, the toroidal continuously variable transmission can be obtained while sufficiently securing the strength and rigidity of the input side disk unit even when the input torque is large, such as a continuously variable transmission for a generator used in an aircraft or the like. The entire machine can be made compact, lightweight and simple.

  The toroidal continuously variable transmission according to the present invention can be used as an automatic transmission for rotating the rotating shaft, which is an output shaft, at a constant speed regardless of the rotational speed of a drive source such as an engine. . That is, if the toroidal continuously variable transmission is incorporated between an input shaft of a generator used in an aircraft or the like and an output shaft of a drive source such as an engine, the rotational speed of the output shaft of the drive source varies. Regardless, the input shaft of the generator can be rotationally driven at a constant rotational speed, and the frequency of the generator can be stabilized. In addition, since the maximum output of such a generator is set to a predetermined magnitude in advance, the rotational speed of the input shaft of the generator is constant regardless of the rotational speed of the output shaft of the drive source. The input torque to the automatic transmission incorporated between the drive source and the generator (the transmission torque of the automatic transmission) reduces the reduction ratio of the automatic transmission (the output of the drive source). It becomes larger as the rotation speed of the shaft becomes slower. For this reason, if the toroidal type continuously variable transmission of the present invention is used as the automatic transmission, the above-described effects of the present invention can be remarkably obtained.

FIG. 3 is a cross-sectional view showing a first example of an embodiment of the present invention, in which a pair of output side disks and a pair of input side disks are taken out. The X section enlarged view of FIG. The figure similar to FIG. 2 for demonstrating the concept of the bottom part thickness in another shape. The figure similar to FIG. 1 which shows the 2nd example of embodiment of this invention. Sectional drawing which shows the 1st example of the toroidal type continuously variable transmission of conventional structure. YY sectional drawing of FIG. Sectional drawing which shows the 2nd example of the toroidal type continuously variable transmission of conventional structure. The diagram which shows the relationship between the reduction ratio of a toroidal type continuously variable transmission, the input torque to this toroidal type continuously variable transmission, and the rotation speed of each disk.

[First example of embodiment]
1 to 3 show a first example of an embodiment corresponding to claims 1 and 2. The feature of the toroidal type continuously variable transmission of the present invention, including the present example, is that a pair of output side discs 16a, The thickness of the 16b and the pair of input side disks 17 and 17 in the axial direction is appropriately regulated. Since the structure and operation of the other parts are the same as those of conventionally known toroidal continuously variable transmissions, including the structure shown in FIGS. 5 to 7 described above, the illustration and explanation of the equivalent parts are omitted or simplified. In the following, the characteristic part of this example will be mainly described.

  In the case of this example, a pair of output side disks 16a and 16b are arranged around both ends of the rotating shaft 1 (see FIGS. 5 to 7), and the inner side surfaces, each of which is a toroidal curved surface having an arcuate cross section, are opposed to each other. In this state, it is supported so as to be able to rotate in synchronization with the rotary shaft 1 and to be capable of relative displacement in the axial direction with respect to the rotary shaft 1. Further, an input cylinder such as the cylinder member 4 shown in FIG. 5 is supported around the intermediate portion of the rotary shaft 1 so as to freely rotate relative to the rotary shaft. An input gear such as a gear 5 (see FIG. 5) is fixed to the axially central portion of the outer peripheral surface of the input cylinder, and a pair of input-side discs 17 and 17 are splined at both axial ends. It is supported in a state in which it can be rotated in synchronization with the input cylinder by engagement or the like, and the axial relative displacement with respect to the input cylinder is prevented. In this state, they are opposed to the inner side surfaces of the two input side disks 17 and 17 and the inner side surfaces of the two output side disks 16a and 16b, each of which is a toroidal curved surface. Then, a plurality of power rollers 7 and 7 (see FIGS. 5 and 6) each having a spherical convex surface are sandwiched between the input disks 17 and 17 and the output disks 16a and 16b. doing.

  During operation of the toroidal-type continuously variable transmission as described above, both the input side disks 17 and 17 are rotationally driven via the input gear and the input cylinder. At the same time, one of the output side disks 16a and 16b (left side in FIG. 1) is connected to the other side (right side in FIG. 1) by a hydraulic pressing device 12a (see FIG. 7). ) Toward the output side disk 6c, and the surface pressure of the rolling contact part (traction part) between the peripheral surface of each of the power rollers 7 and 7 and the inner surface of each of the disks 16a, 16b and 17 is increased. As a result, the rotations of both the input side disks 17 and 17 are transmitted to the both output side disks 16a and 16b via the power rollers 7 and 7, and are taken out from the rotary shaft 1 which is an output shaft.

In the case of this example, of the two output side disks 16a and 16b, the toroidal-type continuously variable transmission is a portion that is in rolling contact with the peripheral surfaces of the power rollers 7 and 7 when the reduction ratio of the toroidal type continuously variable transmission is maximum. , The thickness (T _16a , T _16b ) in the axial direction of the portion near the outer diameter is set so that each of the input power disks 17 and 17 has the reduction ratio of the toroidal continuously variable transmission at a maximum speed increase. It is smaller than the thickness (T ₁₇ ) in the axial direction of the portion near the outer diameter, which is a portion that is in rolling contact with the peripheral surfaces of the rollers 7 and 7 (T ₁₇ > T _16a , T _16b ). Further, the thickness (T _16a ) in the axial direction of the portion near the outer diameter of the one output side disk 16a on the side where the pressing device 12a is provided is set closer to the outer diameter of the other output side disk 16b on the opposite side. The thickness is smaller than the thickness (T _16b ) in the axial direction of the portion (T _16a <T _16b ). That is, the thickness (T _16b ) in the axial direction of the portion near the outer diameter of the other output side disk 16b is larger than the thickness (T ₁₇ ) in the axial direction of the portions near the outer diameter of the input disks 17 and _17. Is smaller than the thickness (T _16a ) in the axial direction of the portion near the outer diameter of the one output side disk 16a (T ₁₇ > T _16b > T _16a ).

To this end, specifically, the bottom wall thickness T _16b of the other output disk 16b, the smaller than the bottom wall thickness T ₁₇ of the two input-side disks 17 and 17, of the one output-side disks 16a It is larger than the bottom thickness T _16a (T _16a <T _16b <T ₁₇ ). The concept of the bottom wall thickness referred to here will be described with reference to FIGS. First, it is a part of an arc that constitutes the bus on the inner surface (including the bus extension) of each of the disks 16a, 16b, and 17 and the bus on the inner surface of the mating disk facing the axial direction (extension of the bus). The portion having the longest distance in the axial direction from the arc that constitutes the arc is the bottom of each of the disks 16a, 16b, and 17. For example, as shown in FIG. 2, when the curvature center O _16b of the inner surface of the other of the output side disk 16b exists radially inwards than the outer peripheral edge of the other of the output side disk 16b is the other Of the inner surface of the output side disk 16b, the position where the radial position is aligned with the center of curvature O _16b is the bottom of the inner side surface of the other output side disk 16b (the portion indicated by the point α in FIG. 2). . A distance _T16b in the axial direction between the bottom and the outer surface of the other output side disk 16b is defined as the bottom thickness of the other output side disk 16b. The outer surface of each of the disks 16a, 16b, and 17 referred to here is, for example, closer to the outer diameter of the outer surface of the one output side disk 16a so as to form a cylinder portion of the hydraulic pressing device 12a. The part except the protrusion 18 etc. which were formed in the part is said.

On the other hand, as shown in FIG. 3, when the center of curvature O _16b of the inner surface of the other output side disk 16b exists radially outward from the outer peripheral edge of the other output side disk 16b, FIG. As shown by the chain line, a state is considered in which the inner side surface of the other output side disk 16b is extended radially outward with the same radius of curvature. In this case, the position where the radial position of the extended portion is aligned with the curvature center O _16b is the bottom portion (the portion indicated by the point β in FIG. 3) of the inner side surface of the other output side disk 16b. A distance _T16b in the axial direction between the bottom and the outer surface of the other output side disk 16b is defined as the bottom thickness of the other output side disk 16b. In any case, in the case of this example, the bottom wall thickness T _16b of the other output side disk 16b is smaller than the bottom wall thickness T _{17 of the} both input side disks 17 and 17, and the one output side disk It is larger than the bottom wall thickness T _{16a of the} disk 16a (T _16a <T _16b <T ₁₇ ).

According to the toroidal type continuously variable transmission of this example configured as described above, it is possible to configure a small size, light weight, and simple while preventing the occurrence of gross slip. That is, in the case of this example, the thickness (T ₁₇ ) in the axial direction of the portion near the outer diameter of the pair of input side disks 17 and 17 is set to the axial direction of the portion near the outer diameter of the pair of output side disks 16a and 16b. The wall thickness (T _16a , T _16b ) is greater than (T ₁₇ > T _16a , T _16b ). In an acceleration state where the speed increasing ratio between the both input side disks 17 and 17 and the both output side disks 16a and 16b is large (the reduction ratio is small), the inner side surfaces of the both input side disks 17 and 17 Thus, the portion near the outer diameter having a relatively small thickness in the axial direction (smaller than the portion closer to the inner diameter) is in rolling contact with the peripheral surfaces of the power rollers 7 and 7. In such a deceleration state, the torque transmitted by the toroidal-type continuously variable transmission increases, but in the present example, the bottom wall thickness T17 of both the input side disks 17, ₁₇ is increased. Thereby, in the case of this example, the amount of elastic deformation of both the input-side discs 17 and 17 is suppressed to prevent the occurrence of gross slip, and one output-side disc 16a by the pressing device 12a (see FIG. 7). The amount of pressing can be suppressed. On the other hand, in a deceleration state where the speed increasing ratio between the both input side disks 17 and 17 and the both output side disks 16a and 16b is small (the reduction ratio is large), the inner side surfaces of the both output side disks 16a and 16b A portion closer to the outer diameter is in rolling contact with the peripheral surface of each of the power rollers 7 and 7. In such a deceleration state, the torque transmitted by the toroidal-type continuously variable transmission is small, and the axial force applied from the power rollers 7 and 7 to the output disks 16a and 16b as a result of this torque transmission is as follows. Limited (small compared to the speed-up state). Therefore, even if the wall thickness in the axial direction of the outer diameter portions of both the output side disks 16a, 16b is smaller than the wall thickness in the axial direction of the outer diameter portions of the both input side disks 17, 17b, The strength and rigidity of both the output side disks 16a and 16b can be secured.

In particular, in the case of this example, the thickness (T _16b ) in the axial direction of the portion on the outer diameter side of the other output side disk 16b of the two output side disks 16a and 16b is similarly set to the outer diameter of the one output side disk 16a. It is larger than the wall thickness (T _16a ) in the axial direction of the shift portion (T _16b > T _16a ). In the case of this example, both the output side disks 16a and 16b are supported around both ends of the rotary shaft 1 (see FIGS. 5 to 7), and one of the output side disks 16a and 16b is the output side disk. The pressing device 12a is provided between 6b and the rotary shaft 1. Accordingly, the axial force applied from the power rollers 7 and 7 to the one output side disk 6b as the torque is transmitted is supported by the pressing device 12a. On the other hand, the axial force applied to the other output side disk 16b is not supported. For this reason, in the case of this example, the thickness (T _16b ) in the axial direction of the portion near the outer diameter of the other output side disk 16b is related to the axial direction of the portion near the outer diameter of the one output side disk 16a. By making it larger than the wall thickness (T _16a ) (T _16b > T _16a ), the elastic deformation amount of the other output side disk 16 b is suppressed. For this reason, also from this aspect, it is possible to prevent the occurrence of gross slip, and to further reduce the size and weight of the toroidal continuously variable transmission.
Further, since the toroidal type continuously variable transmission of this example can be used alone without being combined with other transmissions such as a planetary gear type transmission, for example, as in the structure described in Patent Document 2 above, The structure is not complicated and can be configured simply.

[Second Example of Embodiment]
FIG. 4 shows a second example of an embodiment of the present invention corresponding to claim 1. The toroidal type continuously variable transmission of the present example includes an integrated input side disk 17a having a toroidal curved surface having an arcuate cross section on both sides in the axial direction around the intermediate portion of the rotary shaft 1 (see FIGS. 5 to 7). A relative rotation with respect to the rotating shaft 1 is supported. Then, one of the output side disks 16a and 16b (left side in FIG. 4) of the pair of output side disks 16a and 16b supported so as to be able to rotate in synchronization with the rotary axis 1 around both ends of the rotary axis 1 Similarly, the thickness in the axial direction of the portion near the outer diameter is made smaller than the thickness in the axial direction of the portion near the outer diameter of the output side disk 16b on the other side (right side in FIG. 4). In the case of this example, since the input side disk 17a has an integral structure, the force applied to both side surfaces of the input side disk 17a in the axial direction during operation of the toroidal type continuously variable transmission is the input side disk 17a. Within each other. The thickness of the input side disk 17a in the axial direction is determined by design based on the magnitude of torque applied to the input gear 19 which is a helical gear formed on the outer peripheral surface of the input side disk 17a. . That is, when the input torque is not so large, the thickness in the axial direction of the portion near the outer diameter of the input side disk 17a is set to be larger than the thickness in the axial direction of the portion near the outer diameter of the one output side disk 16a. Can also be reduced.
The configuration and operation of the other parts are the same as in the first example of the embodiment described above.

  The toroidal-type continuously variable transmission of the present invention has an output shaft regardless of the rotational speed of a drive source such as an engine that drives and rotates an input-side disk unit, such as a transmission incorporated in a generator such as an aircraft. It can be preferably used as an automatic transmission for rotating a certain rotating shaft at a constant speed.

DESCRIPTION OF SYMBOLS 1 Rotating shaft 2a, 2b Outer disk 3 Ball spline 4 Output cylinder 5 Output gear 6, 6a Inner disk 7 Power roller 8 Trunnion 9 Support shaft 10 Tilt shaft 11 Drive shaft 12, 12a Pressing device 13 Actuator 14 Radial needle bearing 15 Gear 16a, 16b Output side disc 17, 17a Input side disc 18 Projection 19 Input gear

Claims (2)

A rotation axis;
A pair of output side disks supported at both ends of the rotating shaft so as to be able to rotate in synchronization with the rotating shaft, with the inner surfaces of each having an arc cross section facing each other,
Relative rotation with respect to the rotating shaft was supported freely in the state between the two output-side disks around the middle part of the rotating shaft, with both side surfaces in the axial direction facing the inner surfaces of the two output-side disks. An input disk unit,
The respective circumferential surfaces formed as spherical convex surfaces are in rolling contact with the inner side surfaces of the two output side discs and the two axial side surfaces of the input side disc unit, respectively, and the inner side surfaces of the two output side discs and the input side. A plurality of power rollers rotatably supported between the axially opposite side surfaces of the side disk unit;
Provided between the rotating shaft and one of the output side disks, and presses the one output side disk toward the other output side disk of the two output side disks. In a toroidal continuously variable transmission comprising a pressing device,
A toroidal-type continuously variable transmission characterized in that a thickness in the axial direction of the outer diameter portion of the one output side disk is smaller than a thickness in the axial direction of the outer diameter portion of the other output side disk. .   The input-side disk unit is composed of a pair of input-side disk elements, and the wall thickness in the axial direction of the outer-diameter portion of the other output-side disk is the outer-diameter portion of both the input-side disk elements. The toroidal continuously variable transmission according to claim 1, wherein the toroidal continuously variable transmission is smaller than a wall thickness in the axial direction.

Images