JP4483382B2 - Toroidal continuously variable transmission - Google Patents

Description

  The toroidal continuously variable transmission according to the present invention is used, for example, as a transmission unit constituting an automatic transmission for automobiles or as a transmission for adjusting the operating speed of various industrial machines such as pumps.

  As described in many publications such as Patent Document 1 and Non-Patent Documents 1 and 2, the use of a toroidal continuously variable transmission as a transmission unit of an automatic transmission for automobiles has been studied. Has been implemented in. 2 to 3 are called double-cavity types among such toroidal-type continuously variable transmissions, and each of them is claimed around the input rotary shaft 1 which is the rotary shaft described in the claims. A pair of input-side disks 2a and 2b, which are outer disks described in the above-mentioned range, are supported. These input side disks 2a, 2b are each a toroidal curved surface (concave arc-shaped concave surface) with respect to the input rotation shaft 1, and are on the input side corresponding to one axial side surface recited in the claims. In a state where the side surfaces 3 and 3 are opposed to each other, concentric and synchronized rotation is supported freely.

  One of these input side disks 2a, 2b (right side in FIG. 2) is connected to a portion near one end of the input rotating shaft 1 (right side near FIG. 2) by a ball spline 5. The displacement in the direction is supported freely. On the other hand, the input disk 2b on the other side (left side in FIG. 2) has a stepped surface 4a provided near the inner diameter thereof, and a portion closer to the other end of the input rotating shaft 1 (the left end portion in FIG. 2). The input rotary shaft 1 is supported by spline engagement in a state where it is brought into contact with a step surface 4b provided on the outer peripheral surface. Therefore, the other input-side disk 2b is in a state where the displacement from the state in which the stepped surfaces 4a and 4b are in contact with each other to the other in the axial direction (the left side in FIG. 2) is prevented. The rotary shaft 1 is supported. One of the input disks 2a, 2b is freely pressed toward the other input disk 2b by a hydraulic pressing device 6.

  Further, the input rotary shaft 1 has a casing 7 with one end (right end in FIG. 2) allowed to be displaced in the axial direction by the cylindrical roller bearing 9 and the other end (left end in FIG. 2). In a state in which axial displacement is prevented by row angular ball bearings 8, the ball bearings 8 are rotatably supported. In addition, an output side disk 10 corresponding to the inner disk described in the claims is supported at an intermediate portion of the input rotary shaft 1 by radial needle bearings 11 and 11 so as to be capable of relative rotation and axial displacement. . In this state, each output-side inner surface 12, 12 of each output-side disk 10, each of which is a toroidal curved surface and corresponding to both sides in the axial direction described in the claims, corresponds to each of the input-side inner surfaces 3. 3 is opposed. Further, the output gear 13 formed directly on the outer peripheral surface of the output disk 10 is engaged with another output gear fixed to an output rotation shaft (not shown) so that the power of the output gear 13 can be transmitted to the output rotation shaft. Yes.

  Further, a plurality of (generally, two or three) power rollers 14 are provided in a portion (cavity) between the input side and output side inner side surfaces 3 and 12 around the input rotary shaft 1. 14 are arranged. Each of these power rollers 14 and 14 has a spherical convex surface on the peripheral surfaces 15 and 15 contacting the input side and output side inner side surfaces 3 and 12, respectively. Support shafts 17 and 17 corresponding to the eccentric shaft described in the range, radial needle bearings 18 and 18, thrust ball bearings 19 and 19 corresponding to the first thrust bearing described in the claims, and second The thrust needle bearings 20 and 20 corresponding to the thrust bearings are supported so as to be freely rotatable and slightly oscillating. That is, each of the support shafts 17 and 17 is an eccentric shaft in which a base half portion and a front half portion are eccentric from each other, and the base half portion of the support shafts 17 and 17 is provided at an intermediate portion of the trunnions 16 and 16 as another radial needle bearing. 21 and 21 are supported so as to be swingable and displaceable. The power rollers 14 and 14 are rotatably supported on the front half portions of the support shafts 17 and 17 by the radial needle bearings 18 and 18 and the thrust ball bearings 19 and 19, respectively. Further, the displacement of each of the power rollers 14 and 14 in the axial direction of the input rotary shaft 1 based on the elastic deformation of each constituent member is changed to the thrust needle bearings 20 and 20 and the other radial needle bearings 21 and 21. Because of this, it is free.

  Each trunnion 16, 16 has pivots 22, 22 provided concentrically with each other for each trunnion 16, 16 at both ends in the length direction (front and back direction in FIG. 2, vertical direction in FIG. 3). The center is swingable and displaceable. At the time of shifting, the trunnions 16 and 16 are displaced in the axial direction of the pivots 22 and 22 by supplying and discharging pressure oil to and from the actuators 23 and 23. As a result, rolling contact portions (traction portions) between the peripheral surfaces 15 and 15 of the power rollers 14 and 14 and the input and output inner surfaces 3 and 12 of the input and output disks 2a and 2b and 10 respectively. ), The direction of the force acting in the tangential direction changes, and the trunnions 16 and 16 swing and displace about the pivots 22 and 22, respectively. The peripheral surfaces 15, 15 of each of the power rollers 14, 14 are connected to the radially outer portions of the input side inner surfaces 3, 3 of the input side disks 2a, 2b and the output side inner surface 12 of the output side disk 10. , 12 in rolling contact with the radially inward portion, the gear ratio between the two disks 2a, 2b, 10 is increased. On the other hand, the peripheral surfaces 15 and 15 of the power rollers 14 and 14 are connected to the radially inward portions of the input side inner surfaces 3 and 3 of the input side disks 2a and 2b and the output side disk 10 respectively. If rolling contact is made with the radially outer portions of the output side inner surfaces 12, 12, the gear ratio between the two disks becomes the deceleration side.

  During the operation of the toroidal type continuously variable transmission as described above, the pressing device 6 presses the pair of input disks 2a and 2b in a direction approaching each other, The power is transmitted to the output disk 10 via the power rollers 14 and 14. The pressing device 6 presses the one input side disk 2a toward the other input side disk 2b by introducing pressure oil into the pair of hydraulic chambers 24a and 24b. Further, a preload spring 25 such as a disc spring is provided in one of the hydraulic chambers 24a and 24b (on the right side in FIG. 2), and hydraulic pressure is introduced into the hydraulic chambers 24a and 24b. Even in a state in which the rolling contact portion between the input side and output side inner surfaces 3 and 12 of the input side and output side disks 2a, 2b and 10 and the peripheral surfaces 15 and 15 of the power rollers 14 and 14 is not The minimum surface pressure is ensured.

  By the way, in the case of the toroidal-type continuously variable transmission as described above, when the constituent members are elastically deformed based on the pressing force generated by the pressing device 6 during operation, the above-described respective components are absorbed to absorb the displacement of the constituent members. The power rollers 14 and 14 swing (circulate) around the base half of the support shafts 17 and 17. Moreover, not only one input side disk 2a (as shown in FIG. 2), but also the output side disk 10 is displaced in the axial direction of the input rotary shaft 1 as shown in FIGS. In the case of the structure in which the axial position of the input side disk 2b (on the left side in FIG. 2) is fixed, the swing amount (arc momentum) of each of the power rollers 14 and 14 is the respective cavity (the left and right cavities in FIG. 2). 26a and 26b are different from each other. More specifically, the swing amount of each of the power rollers 14 and 14 in the cavity 26a on one side (right side in FIG. 2) is the swing amount of each of the power rollers 14 and 14 in the cavity 26b on the other side (left side in FIG. 2). Bigger than. The reason is that the one input side disk 2a and the output side disk 10 are displaced in the axial direction of the input rotary shaft 1, whereas the trunnions 16, 16 that support the power rollers 14, 14 and the other This is because the input side disk 2b is not displaced in the axial direction of the input rotation shaft 1.

  On the other hand, as shown in FIGS. 4A to 4D, in the state where each of the power rollers 14 is inclined (the transmission ratio of the toroidal type continuously variable transmission deviates from 1), each of these power rollers When 14 swings around the base half of the support shaft 17 based on the increase or decrease of the pressing force generated by the pressing device 6, the power rollers 14 move in directions indicated by arrows in FIG. It is displaced to. FIG. 4 shows the relationship between the tilted state of the upper right power roller 14 of the power rollers 14 and 14 shown in FIG. 2 and the swinging direction. For example, as shown in FIG. 4A, when the power roller 14 swings toward the output-side disk 10 during deceleration, the power roller 14 is displaced diagonally to the upper left in the figure. Further, as shown in FIG. 4B, when the power roller 14 swings toward the input side disk 2a during deceleration, the power roller 14 is displaced diagonally to the lower right in the figure. On the other hand, as shown in FIG. 4C, when swinging toward the output-side disk 10 at the time of speed increase, the power roller 14 is also shown in FIG. Similarly, when swinging toward the input-side disk 2a at the time of acceleration, the power roller 14 is displaced diagonally to the upper right in FIG.

As apparent from FIG. 4, when the power roller 14 is swung in an inclined state, the power roller 14 is not only displaced in the axial direction of the input rotary shaft 1 but also the disks 2a, 10 It is also displaced in the radial direction. Based on the displacement of the power roller 14, the rolling contact portion between the peripheral surface 15 of the power roller 14 and the input side and output side surfaces 3 and 12 of the input side and output side disks 2 a and 10. (Traction part) The position of a is displaced from the position indicated by the solid line in FIG. 4 to the position indicated by the chain line. That is, the power roller 14 is displaced not only in the axial direction of the input rotary shaft 1 as described above but also in the radial direction of the disks 2a and 10, whereas the disks 2a and 10 are only in the axial direction. Due to the displacement, the position of each rolling contact portion a is displaced in the radial direction of each of the disks 2a and 10 (the axial direction of the power roller 14). In particular, as shown in FIGS. 4A and 4D, when the power roller 14 swings in a direction that also displaces radially outward (upward in FIG. 4) of the disks 2a and 10. The positions of the respective rolling contact portions a are radially outward of the respective disks 2a and 10 (the axial base end side of the power roller 14), that is, the half apex angle γ _A (opening angle) of the power roller 14. θ _A ) is displaced in the opening direction. Such displacements of the respective rolling contact portions A are the same in the same cavity 26a (26b) with respect to the radial direction of the respective disks 2a, 2b, and 10. Further, between the different cavities 26a and 26b, the one of the cavities 26a, which is a cavity on the side where the swinging amount of each of the power rollers 14 and 14 is increased, is largely displaced in the radial direction.

When each rolling contact portion i is displaced in the direction in which the half apex angle γ _A is opened as described above, the contact ellipse formed in each rolling contact portion a is the peripheral surface 15 of each power roller 14 and each disk. It becomes easy to reach the end edges of 2a and 10, and it is easy to cause damage to each of the power rollers 14 and the disks 2a and 10 due to edge loading. In particular, as shown in FIG. 4A, each power roller 14 swings toward the output side disk 10 in a decelerating state and on the basis of an increase in pressing force generated by the pressing device 6. When moving, the surface pressure of each of the rolling contact portions a increases. In this way, it is not particularly preferable that the contact ellipse reaches the peripheral surface 15 of each power roller 14 and the edges of the respective disks 2a and 10 in the state where the surface pressure of each rolling contact portion a increases. Further, in such a state that the surface pressure of each rolling contact portion i increases, the position of each rolling contact portion i, b between the cavities 26a, 26b is the diameter of each of the disks 2a, 2b, 10 described above. If the directions differ greatly, the amount of slippage of these rolling contact portions a and b increases, and the durability and transmission efficiency may decrease.

JP-A-6-280959 Motoo Aoyama, "Bessed Best Car Red Badge Series 245 / A book that understands the latest mechanics of cars", Sanyusha Co., Ltd./Kodansha Co., Ltd., December 20, 2001, p. 92-93 Hirohisa Tanaka, “Toroidal CVT”, Corona Inc., July 13, 2000

  In view of the circumstances as described above, the toroidal continuously variable transmission according to the present invention has a structure in which one outer disk and inner disk are displaced in the axial direction of the rotating shaft, and is intended to improve durability and transmission efficiency. Invented.

The toroidal type continuously variable transmission of the present invention has a rotating shaft, a pair of outer disks, an inner disk, a plurality of trunnions, and a plurality of power rollers, similarly to the structure shown in FIGS. And a pressing device.
Among these, the rotating shaft is supported in the casing so as to be rotatable and prevented from axial displacement.
Each of the outer disks rotates in synchronization with the rotation shaft at two positions in the axial direction of the rotation shaft in a state in which the respective one side surfaces in the axial direction, which are concave surfaces each having an arcuate cross section, are opposed to each other. It is supported as free.
In addition, the inner disk has a relative to the rotating shaft in a state in which both axial side surfaces, which are concave surfaces having an arcuate cross section, are opposed to one axial side surface of each outer disk around the intermediate portion of the rotating shaft. Rotation is supported freely.
Further, each trunnion is centered on a pivot that is twisted with respect to the rotational axis, and a plurality of trunnions are arranged at positions between both axial sides of the inner disk and one axial side of each outer disk. The rocking displacement is freely provided.
Each power roller is rotatably supported by each trunnion and has a spherical convex surface that is in contact with both axial side surfaces of the inner disk and one axial side surface of each outer disk. ing.
The pressing device presses the outer disk and the inner disk in a direction to bring them closer to each other.
One of the outer disks and the inner disk are provided around the rotating shaft so as to be displaceable in the axial direction of the rotating shaft directly or via another member, and the other outer disk. A disk is provided around the rotary shaft in a state where displacement of the rotary shaft in the axial direction is prevented.

  In particular, in the toroidal type continuously variable transmission of the present invention, each power present in one cavity between the one outer disk and the inner disk in a state where the pressing device does not generate a pressing force. The position of the rolling contact portion between the circumferential surface of the roller and each side surface in the axial direction of each disk, the circumferential surface of each power roller existing in the other cavity that is a portion between the other outer disk and the inner disk, and the above These discs are positioned inward in the radial direction of each disc rather than the position of the rolling contact portion with each side surface in the axial direction of each disc.

  According to the toroidal type continuously variable transmission of the present invention configured as described above, each rolling contact portion (traction portion) of one cavity, which is a cavity on the side where the swing amount of each power roller is increased, is set to each disk. In the radial direction (the axial direction of each power roller), it is difficult to displace outward (base end side). That is, each rolling contact portion of the one cavity is positioned so that the position of each rolling contact portion of the one cavity is positioned inward in the radial direction of each disk compared to the position of each rolling contact portion of the other cavity. Can be made difficult to displace radially outward of each disk {the half apex angle (opening angle) of each power roller can be made difficult to open}. Therefore, the surface pressure of each of the rolling contact portions is increased, and the power rollers of the one cavity displace the rolling contact portions of the one cavity outward in the radial direction of the disks. Even in the case of rocking in the direction in which the half apex angle is opened, the contact ellipse of each rolling contact portion of this one cavity can hardly reach the peripheral surface of each power roller or the edge of each disk. In addition, in the state where the surface pressure of each rolling contact portion is intermediate (the intermediate state between the state where the surface pressure of each rolling contact portion is maximized and the state where it is minimized), If the positions of the rolling contact portions are made to coincide with each other in the radial direction of each disk, the slip generated at each rolling contact portion can be reduced, and durability and transmission efficiency can be improved.

  In addition, as described above, the power rollers of the one cavity move the rolling contact portions of the one cavity to the positions corresponding to the positions of the rolling contact portions of the one cavity in the radial inner direction of the disks. When oscillating in a direction in which the disc is displaced inward in the radial direction (a direction in which the half apex angle is closed), each of the rolling contact portions is easily displaced inward in the radial direction of each of the discs (half of each power roller). The apex angle is easy to close). However, when the respective rolling contact portions are displaced inward in the radial direction of each disk (the half apex angle of each power roller is closed), the contact ellipse of each rolling contact portion is surrounded by the circumference of each power roller. Since it does not easily reach the surface or the edge of each disk, it is not a problem. Further, as described above, the position of each rolling contact portion of one cavity is positioned inward in the radial direction of each disk, and the position of each rolling contact portion between the respective cavities is related to the radial direction of each disk. Mismatches are likely. However, as described above, if the surface pressures of the respective rolling contact portions are in an intermediate state and the positions of the respective rolling contact portions are matched between the cavities, the influence on the durability and transmission efficiency is small. In addition, even when the positions of the rolling contact portions between the cavities are inconsistent, the actuator that changes the gear ratio between the disks by displacing the trunnion that supports the power rollers is provided by Since each trunnion is displaced so that the transmission torques of the rolling contact portions coincide with each other in the respective cavities, it is possible to prevent excessive slippage at the rolling contact portions.

In carrying out the present invention, preferably, as described in claim 2, each power roller is pivotally supported by its base half portion at the middle portion of each trunnion, and its front half portion is placed within each trunnion. It is rotatably supported around the tip half of the eccentric shaft protruding from the side surface. Further, between each of these power rollers and the inner surface of each of the above trunnions, the thrust load applied to each of these power rollers is supported in order from the side of each of these power rollers, and the rotation of each of these power rollers is allowed. There is provided a first thrust bearing and a second thrust bearing that allows the outer ring constituting the first thrust bearing to swing and displace around the base half of each eccentric shaft. Then, the dimensions of the second thrust bearing provided between each power roller existing in one cavity and the inner surface of each trunnion are measured in the axial direction of each power roller with each power roller existing in the other cavity. The size of the second thrust bearing provided between the inner surface of each trunnion is larger than the dimension in the axial direction of each power roller.
If comprised in this way, about a member with comparatively high cost, such as a power roller, a trunnion, and also each disk, the thing of the same specification (same shape and same dimension) can be used between each cavity. For this reason, the increase in the manufacturing cost of a structural member can be suppressed.

In carrying out the invention according to claim 2 as described above, more preferably, as described in claim 3, the second thrust bearing is a thrust needle provided with a thrust trace and a plurality of needles. Use bearings. Then, the thickness dimension of the thrust trace of the thrust needle bearing existing in one cavity is made larger than the thickness dimension of the thrust trace of the thrust needle bearing existing in the other cavity.
By adopting such a configuration, it is only necessary to change the thickness of a member that can be manufactured with a simple shape (simple flat plate shape) at low cost, and therefore the present invention can be implemented at the lowest cost.

  FIG. 1 shows an embodiment of the present invention corresponding to all of claims 1 to 3. The feature of the present embodiment is that the output side disk 10 is rotatably supported while allowing axial displacement, and the power rollers 14 and 14 have large swinging amounts to ensure durability and transmission efficiency. The positions of the respective rolling contact portions (traction portions) (a) and (b) of one side (the right side in FIG. 1) of the cavity 26a are arranged radially outward (each power roller). 14 and 14 in the axial direction proximal end side). Since the structure and operation of the other parts are the same as the structure shown in FIGS. 2 to 3 described above, overlapping illustrations and explanations are omitted or simplified, and the following description will focus on the characteristic parts of this embodiment.

In the case of the present embodiment, in a state where the pressing device 6 does not generate a pressing force, the positions of the rolling contact portions a and i of one cavity 26a are set to the positions of the rolling contacts of the other cavity 26b (left side in FIG. 1). B. Inward with respect to the radial direction of each of the disks 2a, 2b, and 10 with respect to the radial direction {the tip side with respect to the axial direction of the power rollers 14, 14 (the side far from the inner surface of the trunnions 16, 16; the support shaft 17) , 17 at the front end side of the first half)}. That is, in the state where the pressing device 6 does not generate a pressing force, the rolling contact portions A and A of the one cavity 26a are set to the intersections A and A of the normals α and α, respectively, and the rolling contact portion of the other cavity 26b. It is located inward with respect to the radial direction of each of the disks 2a, 2b, 10 from the intersections B, B of the respective normal lines β, β. In other words, in the state where the pressing device 6 does not generate a pressing force, the opening angle (contact angle) θ _A of each power roller 14, 14 in the one cavity 26 a is set to be equal to each power roller 14 in the other cavity 26 b, 14 is smaller than the opening angle θ _B (θ _A <θ _B ).

Therefore, in the case of the present embodiment, the thickness dimensions of the thrust needle bearings 20a, 20a provided between the power rollers 14, 14 existing in the one cavity 26a and the inner surfaces of the trunnions 16, 16 are as follows. the T _20, greater than the thickness t ₂₀ of the thrust needle bearing 20, 20 provided between the power rollers 14, 14 present in the other cavity 26b and the inner surfaces of the trunnions 16, 16 (T _20> and t ₂₀₎ and. For this purpose, the thickness T ₂₇ of each thrust trace 27a, 27a constituting each thrust needle bearing 20a, 20a existing in the one cavity 26a is set to the thrust needle bearing 20, existing in the other cavity 26b, 20 is larger than the thickness dimension t ₂₇ of each thrust trace 27, ₂₇ (T ₂₇ > t ₂₇ ). The distances from the input rotary shaft 1 of the pivots 22 and 22 (see FIG. 3) provided at both ends of the trunnions 6 and 6 are the same between the cavities 26a and 26b.

The difference in thickness between the thrust plates 27 and 27a as described above (= the difference S between the positions of the intersections A and B) indicates that the pressing force generated by the pressing device 6 is in an intermediate state (each rolling contact portion). (B) the surface pressure of the discs 2a, 2b and 10 is in the same direction with respect to the radial direction of each of the disks 2a, 2b, 10 It is preferable to regulate. In other words, it is preferable to regulate the respective opening angles θ _A and θ _B of the cavities 26a and 26b so that the respective rolling contact portions a and b have an intermediate surface pressure.

According to the toroidal-type continuously variable transmission of the present embodiment configured as described above, each rolling contact portion i of the one cavity 26a, which is a cavity on the side where the swing amount of each of the power rollers 14, 14 is increased. Can be less likely to be displaced outward (proximal end side) with respect to the radial direction of each of the disks 2a, 2b, and 10 (the axial direction of each of the power rollers 14 and 14). That is, the positions of the respective rolling contact portions A and B of the one cavity 26a are compared with the positions of the respective rolling contact portions B and B of the other cavity 26b inward in the radial direction of the respective disks 2a, 2b and 10. Therefore, it is possible to make it difficult to displace the rolling contact portions a and i of the one cavity 26a outward in the radial direction of the disks 2a, 2b and 10 {the half apex angle γ of the power rollers 14 and 14}. _A (opening angle θ _A ) can be difficult to open}. Therefore, as shown in FIG. 4A, the power rollers 14 and 14 are moved to the output disk 10 side in a decelerating state and based on an increase in pressing force generated by the pressing device 6. Even when the power rollers 14 and 14 are swung in the direction in which the half apex angle γ _A (opening angle θ _A ) opens, the rolling ellipses of the rolling contact portions a and a are used as the power ellipses. It is possible to make it difficult to reach the peripheral surfaces 15 and 15 of the rollers 14 and 14 and the edges of the disks 2a, 2b, and 10. Further, in the state where the surface pressures of the respective rolling contact portions a and b are intermediate, the positions of the respective rolling contact portions a and b between the respective cavities 26a and 26b are set to the diameters of the respective disks 2a, 2b and 10. Since the directions are matched, it is possible to reduce the slip generated at each of the rolling contact portions A and B, and to improve durability and transmission efficiency.

Incidentally, as described above, the positions of the respective rolling contact portions (a) and (b) of one cavity 26a are positioned inwardly in the radial direction of the respective disks 2a, 2b, and 10, so that (B) and (C) in FIG. In this state, the rolling contact portions a and i are located further inward (the half apex angle γ _A (opening angle θ _A ) of each power roller 14 and 14 is further closed). However, in this way, the respective rolling contact portions A and B are displaced radially inward of the respective disks 2a, 2b, and 10 {the half apex angle γ _A (opening angle θ _A ) of each power roller 14 and 14 is further closed. }, The contact ellipses of the rolling contact portions A and B do not easily reach the peripheral surfaces 15 and 15 of the power rollers 14 and 14 and the edges of the disks 2a, 2b and 10, respectively. There is no particular problem. Further, as described above, the respective rolling contact portions (a) and (b) of one cavity 26a are positioned inwardly in the radial direction of the respective disks 2a, 2b, and 10, so that each of the cavities 26a and 26b is separated from each other. The positions of the rolling contact portions (a) and (b) tend to be inconsistent with respect to the radial direction of the disks 2a, 2b, and 10. However, in the state where the surface pressure of each of the rolling contact portions a and b is in the middle, the positions of the respective rolling contact portions a and i in the radial direction of the respective disks 2a, 2b, and 10 are matched, so that durability and transmission are achieved. The effect on efficiency is small. Further, even when the positions of the rolling contact portions a and b between the cavities 26a and 26b are not matched, the trunnions 16 and 16 that support the power rollers 14 and 14 are displaced to displace the input side, The actuators 23 (see FIG. 3) that change the gear ratio between the output-side disks 2a, 2b, and 10 are arranged so that the transmission torques of the rolling contact portions a and b coincide with each other in the cavities 26a and 26b. Since the trunnions 16 and 16 are displaced, excessive sliding can hardly occur at the rolling contact portions a and b.

Sectional drawing which shows the Example of this invention in the state which the press apparatus does not generate | occur | produce the pressing force. Sectional drawing which shows an example of the conventional structure in the state in which the pressing device is not generating pressing force. XX sectional drawing of FIG. The figure equivalent to the Y section of FIG. 2 which shows the four examples of the relationship between the inclination state of each power roller, and a rocking | fluctuation direction.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Input rotating shaft 2a, 2b Input side disk 3 Input side inner surface 4a, 4b Step surface 5 Ball spline 6 Pressing device 7 Casing 8 Ball bearing 9 Cylindrical roller bearing 10 Output side disk 11 Radial needle bearing 12 Output side inner surface 13 Output Gear 14 Power roller 15 Circumference 16 Trunnion 17 Support shaft 18 Radial needle bearing 19 Thrust ball bearing 20, 20a Thrust needle bearing 21 Radial needle bearing 22 Axis 23 Actuator 24a, 24b Hydraulic chamber 25 Preload spring 26a, 26b Cavity 27, 27a Thrust race

Claims (3)

  The rotating shaft supported in a state that is freely rotatable in the casing and prevented from being displaced in the axial direction, and the rotating shaft in a state in which the respective one side surfaces in the axial direction are concave surfaces each having a circular arc cross section. A pair of outer disks supported so as to freely rotate in synchronization with the rotating shaft at two axial positions of the rotating shaft, and both axial side surfaces which are concave surfaces having a circular arc cross section around the intermediate portion of the rotating shaft. An inner disk that is supported to freely rotate relative to the rotating shaft in a state of being opposed to one side surface in the axial direction of each outer disk, and both axial side surfaces of the inner disk and the axial direction of each outer disk with respect to the axial direction. A trunnion provided with a plurality of oscillating displacements around a pivot axis that is twisted with respect to the rotation shaft, and a trunnion that is rotatably supported by each trunnion and is spherical convex Each of the peripheral surfaces is pressed in a direction to bring the outer disk and the inner disk closer to each other, and a power roller in contact with both axial surfaces of the inner disk and one axial surface of each outer disk. A pressing device, and one outer disk and the inner disk among the outer disks are provided around the rotating shaft so as to be displaceable in the axial direction of the rotating shaft directly or via another member. In the toroidal continuously variable transmission in which the other outer disk is provided in the state where the axial displacement of the rotating shaft is prevented around the rotating shaft, the pressing device does not generate a pressing force, The position of the rolling contact portion between the peripheral surface of each power roller existing in one cavity that is a portion between one outer disk and the inner disk and each axial side surface of each disk, The diameter of each disk is larger than the position of the rolling contact portion between the circumferential surface of each power roller present in the other cavity between the other outer disk and the inner disk and each axial side surface of each disk. A toroidal-type continuously variable transmission characterized by being positioned inward with respect to the direction.   Each power roller pivotally supports its base half at the middle of each trunnion, and supports its front half rotatably around the front half of the eccentric shaft protruding from the inner surface of each trunnion. Between each of these power rollers and the inner surface of each of the above trunnions, the thrust rollers applied to each of these power rollers are supported in turn from the side of each of these power rollers while rotating each of these power rollers. A first thrust bearing to be allowed and a second thrust bearing to allow the outer ring constituting the first thrust bearing to swing and displace around the base half of each eccentric shaft. The dimension of the second thrust bearing provided between each power roller existing in one cavity and the inner surface of each trunnion in the axial direction of the other power roller The second thrust bearing provided between the power rollers and the inner surfaces of the trunnions present, is larger than the dimension in the axial direction of the power rollers, the toroidal type continuously variable transmission according to claim 1. A thrust needle bearing in which the second thrust bearing is a thrust needle bearing having a thrust trace and a plurality of needles, and the thickness of the thrust trace of the thrust needle bearing existing in one cavity is present in the other cavity The toroidal-type continuously variable transmission according to claim 2, which is larger than a thickness dimension of the thrust trace.

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