JP2015200330A - Toroidal type continuously variable transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure in which gross slip can be effectively prevented from occurring at each traction part even when a support plate is inclined with change operation of a transmission ratio between respective disks.SOLUTION: A toroidal type continuously variable transmission includes gross slip prevention means. When in opposite parts of the side surface of a support plate and the shoulder part of a trunnion, at least one distance D between the opposite parts is a predetermined value α or less, the gross slip prevention means prevents occurrence of excessive slip at a traction part to be a rolling contact part between an axial one-side surface of each disk and the peripheral surface of each power roller.

Description

  The present invention relates to an improvement in a toroidal continuously variable transmission that is used as a transmission for an automobile or as a transmission for adjusting the operating speed of various industrial machines such as a pump.

  The use of a toroidal type continuously variable transmission as a transmission for an automobile is partly implemented and well known. 9 to 10 show the basic configuration of a toroidal continuously variable transmission having a conventional structure. This toroidal-type continuously variable transmission has a pair of outer disks 2 and 2 around the portions near both ends of the rotating shaft 1 and the rotating shaft 1 with the inner side surfaces each being a toroidal curved surface facing each other. Supports the rotation synchronized with. A cylindrical member 3 is supported around the intermediate portion of the rotary shaft 1 so as to be rotatable with respect to the rotary shaft 1. Further, on the outer peripheral surface of the cylindrical member 3, a gear 4 is fixed at the center in the axial direction, and a pair of inner disks 5 and 5 are attached to both ends in the axial direction by spline engagement. The rotation synchronized with 3 is supported. In this state, the inner side surfaces of the inner disks 5 and 5, each of which is a toroidal curved surface, are opposed to the inner surfaces of the outer disks 2 and 2.

  Further, a plurality of power rollers 6 and 6 each having a spherical convex surface are sandwiched between the outer disks 2 and 2 and the inner disks 5 and 5. The power rollers 6 and 6 are rotatably supported by trunnions 7 and 7, respectively. The trunnions 7 and 7 are tilted with respect to the central axes of the disks 2 and 5, respectively. The shafts 8 and 8 are supported so as to be swingable and displaceable. That is, each of the trunnions 7 and 7 includes a pair of tilting shafts 8 and 8 provided concentrically with each other at both axial ends, and a supporting beam existing between the tilting shafts 8 and 8. Portions 9 and 9, and these tilting shafts 8 and 8 are supported by radial needle bearings 11 and 10 with respect to support plates 10 and 10 supported by a casing housing the toroidal-type continuously variable transmission. 11 is supported so as to be swingable and axially displaceable. For this purpose, circular holding holes 12 and 12 are formed at the four corners of the support plates 10 and 10 so as to penetrate the support plates 10 and 10, respectively. The radial needle bearings 11 and 11 are provided between the inner peripheral surfaces of the holding holes 12 and 12 and the outer peripheral surfaces of the tilt shafts 8 and 8, respectively. Each of these radial needle bearings 11, 11 includes outer rings 13, 13 whose outer peripheral surfaces are convex curved surfaces that are partially spherical, and these outer rings 13, 13 do not rattle the holding holes 12, 12, and The holding holes 12 and 12 are fitted so as to be capable of displacement in the axial direction and slight swing displacement. The needles 14, 14 constituting each of the radial needle bearings 11, 11 are an inner ring raceway provided on the outer peripheral surface of each tilt shaft 8, 8 and an outer ring raceway provided on the inner peripheral surface of each outer ring 13, 13. It is provided so that it can roll freely.

  Each of the power rollers 6, 6 includes support shafts 15, 15 having base half portions and tip half portions eccentric from each other on the inner side surfaces of the support beam portions 9, 9 constituting the trunnions 7, 7, respectively. Via a plurality of rolling bearings, the support shafts 15 and 15 are supported so as to be able to rotate around the front half of each of the support shafts 15 and 15 and to be slightly oscillating and displaced about the base half of each of the support shafts 15 and 15. ing.

  During the operation of the toroidal-type continuously variable transmission as described above, one of the outer disks 2 (left side in FIG. 9) is rotationally driven by the drive shaft 16 via a loading cam type pressing device 17. As a result, the pair of outer disks 2 and 2 supported at both ends of the rotating shaft 1 rotate in synchronization while being pressed in a direction approaching each other. The rotation is transmitted to the inner disks 5 and 5 through the power rollers 6 and 6 and is taken out from the gear 4. When changing the gear ratio between the rotary shaft 1 and the gear 4, the trunnions 7, 7 are displaced in the axial direction of the tilt shafts 8, 8 by hydraulic actuators 28, 28. 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 6 and 6 and the inner surface of each of the disks 2 and 5 changes (in the rolling contact portion). Side slip occurs). As the direction of the force changes, the trunnions 7 and 7 swing around their tilting shafts 8 and 8, and the peripheral surfaces of the power rollers 6 and 6 and the disks 2 and 8. The contact position with the inner surface of 5 changes. The peripheral surfaces of these power rollers 6 and 6 are in rolling contact with the radially outer portions of the inner surfaces of the outer disks 2 and 2 and the radially inner portions of the inner surfaces of the inner disks 5 and 5. If it does so, the gear ratio between the said rotating shaft 1 and the said gearwheel 4 will become a speed-up side. On the other hand, the peripheral surfaces of the power rollers 6 and 6 are arranged radially inwardly on the inner side surfaces of the outer disks 2 and 2 and radially outward of the inner surfaces of the inner disks 5 and 5. If it is brought into rolling contact with the portion, the transmission gear ratio between the rotary shaft 1 and the gear 4 is reduced.

  During operation of the toroidal type continuously variable transmission as described above, the members used for power transmission, that is, the disks 2 and 5 and the power rollers 6 and 6 are generated by the pressing device 17. Elastically deforms based on the pressing force. Then, with the elastic deformation, the disks 2 and 5 are displaced in the axial direction. Further, the pressing force generated by the pressing device 17 increases as the torque transmitted by the toroidal continuously variable transmission increases, and the elastic deformation amount of the members 2, 5, 6 increases accordingly. Therefore, in order to properly maintain the contact state between the inner surface of each of the disks 2 and 5 and the peripheral surface of each of the power rollers 6 and 6 regardless of the fluctuation of the torque, Therefore, a mechanism for displacing the power rollers 6 and 6 in the axial direction of the disks 2 and 5 is required. In the case of the above-described first example of the conventional structure, the tip half of each of the support shafts 15 and 15 that support the power rollers 6 and 6 is similarly oscillated and displaced about the base half. The power rollers 6 and 6 are displaced in the axial direction.

  In the case of the first example of the conventional structure as described above, the structure for displacing each of the power rollers 6 and 6 in the axial direction is complicated, and parts manufacturing, parts management, and assembly work are all troublesome and costly. It is inevitable that the volume increases. As a technique for solving such a problem, Patent Document 1 describes a structure as shown in FIGS. The second example of this conventional structure is characterized by the structure of the portion that supports the trunnion 7a so that the power roller 6a can be displaced in the axial direction of each disk 2, 5 (see FIG. 9). The basic structure and operation of the type continuously variable transmission as a whole are the same as those of the first example of the conventional structure shown in FIGS.

  The trunnion 7a constituting the second example of the conventional structure exists between a pair of tilting shafts 8a and 8b concentrically provided at both ends, and between these tilting shafts 8a and 8b, and at least And a support beam portion 9a having a cylindrical convex surface 18 on the inner side (upper side in FIGS. 12, 15, 16) in the radial direction of each disk 2, 5 (the vertical direction in FIGS. 12, 15, 16). The two tilting shafts 8a and 8b are supported on the support plates 10 and 10 (see FIG. 10) through radial needle bearings 11a and 11a, respectively, so as to be swingable and axially displaceable.

  Further, as shown in FIGS. 12 and 15, the center axis A of the cylindrical convex surface 18 is parallel to the center axis B of the both tilt axes 8a and 8b, and the center axis B of the both tilt axes 8a and 8b. Rather than the outer side (the lower side of FIGS. 12, 15, 16) in the radial direction of the disks 2, 5. Further, a concave portion 21 having a partially cylindrical surface is radially crossed on the outer surface of the outer ring 20 constituting the thrust ball bearing 19 provided between the support beam portion 9a and the outer surface of the power roller 6a. It is provided in the state. Then, the concave portion 21 is engaged with the cylindrical convex surface 18 of the support beam portion 9a so that the outer ring 20 can be oscillated and displaced in the axial direction of the disks 2 and 5 with respect to the trunnion 7a. I support it.

  Further, a support shaft 15a is fixed to the center of the inner surface of the outer ring 20, and the power roller 6a is freely rotatable around the support shaft 15a via a radial needle bearing 22. I support it. Further, a pair of stepped surfaces 23 and 23 facing each other are provided on the inner surface of the trunnion 7a at a continuous portion between both ends of the support beam portion 9a and the pair of tilting shafts 8a and 8b. . Then, these stepped surfaces 23, 23 and the outer peripheral surface of the outer ring 20 constituting the thrust ball bearing 19 are brought into contact with or in close proximity to each other, and the traction force applied from the power roller 6a to the outer ring 20 is It can be supported by the stepped surfaces 23, 23.

According to the toroidal type continuously variable transmission of the second example of the conventional structure configured as described above, the power roller 6a is displaced in the axial direction of each of the disks 2 and 5, and the amount of elastic deformation of each constituent member is increased. Regardless of the change, a structure capable of appropriately maintaining the contact state between the peripheral surface of the power roller 6a and the disks 2 and 5 can be configured simply and at low cost.
That is, when the toroidal continuously variable transmission is operated, it is necessary to displace the power rollers 6a in the axial direction of the disks 2 and 5 based on elastic deformation of the disks 2 and 5 and the power rollers 6a. And the outer ring 20 of the thrust ball bearing 19 that rotatably supports each of the power rollers 6a is in contact with a concave portion 21 having a partial cylindrical surface provided on the outer surface and a cylindrical convex surface 18 of the support beam portion 9a. While sliding the contact surface, the cylindrical convex surface 18 is oscillated and displaced about the central axis A. Based on this oscillating displacement, a portion of the peripheral surface of each power roller 6a that is in rolling contact with one axial side surface of each disk 2, 5 is displaced in the axial direction of each disk 2, 5; The contact state is properly maintained.

  As described above, the central axis A of the cylindrical convex surface 18 is larger in diameter than the central axes B of the tilting shafts 8a and 8b, which are the swing centers of the trunnions 7a during the shifting operation. Exists with respect to the direction. Therefore, the radius of the rocking displacement about the central axis A of the cylindrical convex surface 18 is larger than the rocking radius at the time of the speed change operation, and the both outer disks 2, 2 and the both inner disks 5, 5. Has little effect on the change in the transmission ratio between (and can be neglected or remain within an easily modifiable range).

  Regardless of the structure that allows displacement of the power rollers 6 and 6a in the axial direction of the disks 2 and 5, when changing the gear ratio of the toroidal type continuously variable transmission, a pair of upper and lower support plates 10 10 tends to be inclined with respect to the horizontal direction (left-right direction in FIG. 9). That is, when changing the gear ratio of the toroidal-type continuously variable transmission, the trunnions 7 and 7a are moved by the actuators 26 and 26 to the shafts of the tilt shafts 8, 8a and 8b provided at both ends. Displace in the direction. At this time, due to friction between the inner peripheral surfaces of the holding holes 12 and 12 of the support plates 10 and 10 and the outer peripheral surfaces of the outer rings 13 and 13 constituting the radial needle bearings 11 and 11, A force in the axial direction of each of the tilting shafts 8, 8a, 8b is applied. The direction in which this force is applied is opposite in the vertical direction on both the left and right sides in FIG. 10, and therefore, the support plates 10 and 10 tend to be inclined. When the gear ratio of the toroidal continuously variable transmission is repeatedly changed only to the deceleration side or the acceleration side, the inclination angles of the support plates 10 and 10 are increased. When the inclination angles of both the support plates 11 and 11 are increased, the support beams from the inclined shafts 8, 8 a, and 8 b of the side surfaces of the both support plates 10 and 10 and the end surfaces of the trunnions 7 and 7 a, respectively. The shoulders 24 and 24 that have come off to the side of the parts 9 and 9a come into contact (contact). In this state, the magnitude of the power (torque) transmitted by the power rollers 6 and 6a rotatably supported by the trunnions 7 and 7a may be inconsistent for the power rollers 6 and 6a. . As a result, some of the power rollers 6 and 6a transmit a larger torque than the other power rollers 6 and 6a (the tangential force applied to the traction portion increases). The power rollers 6 and 6a that transmit a large torque are operated with a larger traction coefficient (= tangential force / normal force) than the other power rollers 6 and 6a. The difference between the driving traction coefficient (the tangential force / normal force according to the torque transmitted by each power roller 6 and 6a) and the limit traction coefficient that represents the limit value of power transmission without causing gross slip ( The margin (safety margin) is reduced, and gloss slip is likely to occur.

  The situation where the driving traction coefficient exceeds the limit traction coefficient must be avoided to prevent the occurrence of gross slip in the traction section. For this purpose, for example, the pressing force generated by the loading cam type pressing device 17 is made sufficiently large {restricted to the maximum value of the pressing force required when the toroidal type continuously variable transmission is operated, It is conceivable to increase the pressing force (normal force) applied to. However, in this case, depending on the driving situation, the surface pressure of each traction section becomes excessive, and the transmission efficiency and durability of the toroidal continuously variable transmission are problematic. Therefore, as a pressing device, for example, as described in Patent Document 2, it is conceivable to use a hydraulic pressing device that can finely adjust the surface pressure (pressing force) of the traction portion. However, if the hydraulic pressure to be introduced is increased excessively in order to keep the traction coefficient of the traction section low, the transmission efficiency and durability are also lowered.

  Patent Document 3 discloses an outer peripheral surface of an outer ring (joint) constituting a radial needle bearing (bearing) for supporting a tilt shaft of a trunnion (friction vehicle support member) so as to be swingable with respect to a support plate (link). The bus bar shape is a convex surface (or concave surface) with a partial arc shape (partial spherical shape), and the inner peripheral surface of the holding hole (joint fitting hole) of the support plate that fits the outer ring is a bus bar shape. Describes a structure with a partially arcuate concave curved surface (or convex curved surface). In the case of such a structure described in Patent Document 3, when the support plate tends to tilt, a moment in a direction returning to the original position (decreasing the tilt angle) acts on the support plate. Patent Document 4 discloses a technique for preventing variation in the transmission torque of each power roller by appropriately regulating the size of the gap between the shoulder portion of the trunnion and the side surface of the support plate. Are listed. However, in any of the inventions described in Patent Documents 3 and 4, if the gear ratio of the toroidal type continuously variable transmission is repeatedly changed only to the deceleration side or the acceleration side, the inclination angle of the support plate becomes large. Thus, there is a possibility that the side surface of the support plate and the shoulder portion of the trunnion come into contact with each other.

In Patent Document 5, a pair of upper and lower support plates (upper link and lower link) are connected to each other by a reinforcing member (upper and lower connection link), so that the shoulder of the trunnion (power roller support member) and the support A structure is described in which the shoulders of all trunnions and the side surfaces of the support plate can be in contact with each other simultaneously when the side surfaces of the plate come into contact with each other. However, in the case of the invention described in Patent Document 5, all trunnion shoulders and side surfaces of the support plate are caused by accumulation of manufacturing errors, assembly errors, etc. of each member constituting the toroidal-type continuously variable transmission. May be difficult to contact at the same time. In addition, the provision of the reinforcing member may increase the manufacturing cost of the toroidal continuously variable transmission, and may increase the size and weight of the entire toroidal continuously variable transmission.
On the other hand, in Patent Document 6, an elastic member is provided between a pair of upper and lower support plates, and elastic force in a direction away from each other is applied to both the support plates, so that these can be changed during the shifting of the toroidal type continuously variable transmission. A technique for preventing the side surfaces of both support plates from contacting the shoulders of the trunnion is described. However, in the case of the invention described in Patent Document 6 as well, the provision of the elastic member increases the manufacturing cost of the toroidal continuously variable transmission, or the entire toroidal continuously variable transmission is large.・ There is a possibility of weight.

JP 2008-25821 A JP 2003-130159 A JP 2000-274504 A JP 2002-213552 A JP 2003-35349 A JP 2006-308036 A

  In view of the circumstances as described above, the present invention can effectively prevent the occurrence of gross slip in each traction portion even when the support plate is inclined in accordance with the change in the gear ratio between the disks. Invented to realize the structure of the toroidal-type continuously variable transmission.

The toroidal continuously variable transmission of the present invention includes at least a pair of disks, a plurality of support members, a support plate, and the same number of power rollers as the support members.
Each of these disks is supported concentrically and freely rotating relative to each other in a state in which the respective one side surfaces in the axial direction, each of which is a toroidal curved surface having an arc cross section, are opposed to each other.
In addition, each of the support members has a plurality of swings with respect to the axial direction, and each of the support members is pivoted about a tilt shaft that is twisted with respect to the central axis of each disk. Dynamic displacement is provided freely.
The support plate is for supporting the tilt shafts provided at both ends of the support members in a state in which the tilt shafts are allowed to swing and to be displaced in the axial direction.
The power rollers are rotatably supported by the support members, and the circumferential surfaces of the spherical convex surfaces are in rolling contact with one axial side surface of the disks.

  In particular, in the toroidal type continuously variable transmission according to the present invention, at least one of the facing portions between the side surface of the support plate and the end surface of each of the support members has a predetermined interval or less. (This interval is 0, that is, including a state in which the side surface of the support plate and the end surface of the support member are in contact), and the axial side surface of each disk and the peripheral surface of each power roller There is provided gloss slip prevention means for preventing the occurrence of excessive slipping at the traction portion which is the rolling contact portion.

When implementing the toroidal type continuously variable transmission of the present invention as described above, for example, as in the invention described in claim 2, the respective disks are pressed toward each other as the hydraulic pressure is introduced into the hydraulic chamber. A hydraulic pressing device is provided. Further, the gloss slip prevention means is calculated for determining the magnitude of the pressing force generated by the pressing device while the shift lever for switching the traveling state is switched to the traveling state (D range or R range). The value of the traction coefficient of the traction portion used in the case where the distance between all the facing portions of the facing portions of the side surface of the support plate and the end surface of each support member is larger than the predetermined value. In comparison, a small value is set.
Further, for example, as in the invention described in claim 3, the gloss slip prevention means is configured such that the shift lever for switching the running state is switched to the non-running state (P range or N range), and the at least one location. It is assumed that the gear ratio between the disks is changed in a direction in which the distance between the opposing portions is increased.

Alternatively, even if the gloss slip prevention means is in a state in which the upper limit value or change speed of the input torque to the toroidal-type continuously variable transmission is in a state where the side surface of the support plate and the end surface of the support member are in contact with each other, It shall be limited to a size that does not cause gross slip in the traction section.
Further, the gloss slip prevention means may be configured such that the upper limit value of the speed change speed of the toroidal-type continuously variable transmission is in a normal state (all of the facing portions between the side surfaces of the support plate and the end surfaces of the support members). It is also possible to reduce the distance between the opposing portions) or to increase the amount of lubricating oil for lubricating the traction portions.

  In the case of the toroidal type continuously variable transmission of the present invention configured as described above, at least one of the facing portions between the side surface of the support plate and the end surface of each support member has a predetermined interval or less. In this case, the supporting plate is provided with a gloss slip prevention means for preventing the occurrence of excessive slip (gross slip) in each traction portion. Even when the vehicle is inclined, it is possible to effectively prevent the occurrence of gross slip in each of the traction portions. Further, when the distance between all the facing portions of the facing portion between the side surface of the supporting plate and the end surface of each supporting member is larger than the predetermined value, the gloss slip prevention means does not operate, The transmission efficiency and durability of the toroidal-type continuously variable transmission will not be reduced.

Sectional drawing which shows the 1st example of embodiment of this invention. The flowchart which similarly shows the operation | movement which becomes the characteristic. The figure equivalent to the A section enlarged view of FIG. 1 which shows two examples of the method of measuring the space | interval of the side surface of a support plate, and the shoulder part of a trunnion. A graph for explaining another two examples. The figure similar to FIG. 2 which shows the 2nd example of embodiment of this invention. The figure similar to FIG. 2 which shows the 3rd example. The figure similar to FIG. 2 which shows the 4th example. The figure similar to FIG. 2 which shows the 5th example. Sectional drawing which shows the 1st example of the toroidal type continuously variable transmission of conventional structure. BB sectional drawing of FIG. The perspective view which looked at the trunnion which supported the power roller via the thrust ball bearing which showed the 2nd example of the conventional structure of a toroidal type continuously variable transmission from the radial direction outer side of the disk. Similarly, the front view shown in the state seen from the circumferential direction of the disk. The top view seen from the upper part of FIG. The side view seen from the right side of FIG. CC sectional drawing of FIG. DD sectional drawing of FIG.

[First example of embodiment]
1 to 4 show a first example of an embodiment of the present invention corresponding to all the claims. The feature of the toroidal type continuously variable transmission of the present invention including this example is that the support plates 10a and 10b are inclined in accordance with the operation of changing the gear ratio between the disks 2, 5 (see FIG. 9). In this case, gloss slip prevention means for effectively preventing the occurrence of gloss slip in each traction section is provided. Since the structure and operation of the other parts are the same as those of conventionally known toroidal-type continuously variable transmissions, including the structures shown in FIGS. 9 to 16 described above, illustrations and explanations of equivalent parts are omitted or simplified. In the following, the characteristic part of this example will be mainly described.

  Also in the case of this example, as in the case of the conventional structure described above, a pair of tilting shafts 8c, 8c provided at both ends in the axial direction of the trunnions 7b, 7b are arranged radially with respect to the both support plates 10a, 10b. The needle bearings 11 and 11 are supported so as to be swingable and axially displaceable. In the case of the illustrated example, among the side surfaces of the both support plates 10a and 10b, the periphery of the holding holes 12 and 12 for internally fitting and holding the outer rings 13 and 13 constituting the radial needle bearings 11 and 11, respectively. In addition, convex portions 25 and 25 are formed. And these each convex part 25 and 25 is the shoulder which is the part which remove | deviated from the said each tilting axis 8c and 8c to the support beam part 9b and 9b side among the axial direction both end surfaces of each said trunnion 7b and 7b, respectively. It is made to oppose the parts 24 and 24. This prevents the positional relationship between the support plates 10a and 10b and the trunnions 7b and 7b from becoming inappropriate.

  In particular, in the toroidal type continuously variable transmission of this example, each of the discs 2, even when both the support plates 10 a and 10 b are inclined in accordance with the operation of changing the gear ratio of the toroidal type continuously variable transmission. 5 (see FIG. 9) and gloss slip prevention means for preventing the occurrence of gloss slip at the traction portion which is a rolling contact portion between the inner surface of the power rollers 6b and 6b. In the case of this example, the gloss slip prevention means includes shoulder portions 24, 24 of the trunnions 7b, 7b, and side surfaces of the support plates 10a, 10b facing the shoulder portions 24, 24. An interval measuring means for measuring the interval of the controller, a controller for calculating a gear ratio (of the toroidal type continuously variable transmission) between the disks 2 and 5, and a hydraulic pressure feed to the hydraulic chamber Along with this, a pressing device that presses one of the pair of outer disks 2 and 2 toward the other outer disk 2 is configured. Among these, the controller measures the rotational speed of each of the disks 2 and 5 measured by the sensor and the position signal of the position switch {signal indicating the operation position (selection position) of the shift lever (operation lever) provided in the driver's seat}. The target gear ratio of the toroidal type continuously variable transmission is calculated based on various signals such as an engine controller signal and an accelerator pedal opening.

  In the case of this example, at least one of the opposed portions of the shoulder portions 24, 24 of the trunnions 7b, 7b and the side surfaces of the support plates 10a, 10b, measured by the distance measuring means. When the distance D between the facing portions is less than or equal to a predetermined value α (D ≦ α), the shift state of the toroidal continuously variable transmission is adjusted to prevent the occurrence of gross slip in each traction portion. I have to. This point will be described with reference to the flowchart of FIG. Note that the processing shown in this flowchart is repeatedly (automatically) performed from when the ignition switch is turned on until it is turned off.

  First, in step 1, it is determined whether or not the interval D is equal to or less than a predetermined value α. For example, as shown in FIG. 3A, this distance D is the side surface opposite to the side surface facing the shoulder portions 24, 24 of each trunnion 7b among the side surfaces of the support plates 10a, 10b. 3A based on the output signal values of the displacement sensors 26a and 26b with the tip portions thereof opposed to the upper surface of the upper support plate 10a and the lower surface of the lower support plate 10b. Can do. When the predetermined value α is 0, that is, whether or not the shoulder portion 24 of the trunnion 7b and the side surface of the support plate 10a (10b) are in contact (contact) at the at least one facing portion. 3B, as shown in FIG. 3 (B), the shoulder 24 of the trunnion 7b and the support plate are loaded by load sensors (pressure sensors) 27, 27 installed on the shoulders 24, 24, respectively. You may make it determine whether 10a (10b) side surface contact | abutted. In the case of the illustrated example, the load sensors 27, 27 are provided in the opening of the lubricating oil flow path 31, and each load sensor 27, 27 has a function as a blind plug. In the case of the trunnion 7b shown in FIG. 3B, the trunnion 7b is provided at both ends in the axial direction of the support beam portion 9b so as to protrude inward in the radial direction of the respective disks 2 and 5. A reinforcing beam 30 is provided between the pair of wall portions 29 and 29 so as to be stretched between the wall portions 29 and 29. However, since the structure and operation of this portion are not related to the gist of the present invention, detailed description thereof is omitted.

  Alternatively, it may be determined whether or not the shoulder 24 and the side surface of the support plate 10a (10b) are in contact with each other based on the difference between the actual transmission ratio of the toroidal-type continuously variable transmission and the command value. it can. That is, as shown in FIG. 4A, after the controller gives an instruction to change the gear ratio of the toroidal continuously variable transmission, the hydraulic pressure is introduced into the hydraulic chambers of the actuators 28 and 28. There is a delay until the trunnions 7b, 7b are displaced in the axial direction of the tilt shafts 8c, 8c and the power rollers 6b, 6b start to swing. When the shoulder 24 of the trunnion 7b and the side surface of the support plate 10a (10b) are in contact with each other, the trunnion 7b cannot be sufficiently displaced in the axial direction of the tilt shafts 8c, 8c, The delay increases. In addition, when the shoulder portion 24 of the trunnion 7b and the side surface of the support plate 10a (10b) are in contact with each other, the transmission torque varies between the traction portions, and some traction portions are limited. The traction coefficient may be reduced. Therefore, the swing start delay of the power roller 6b with respect to the command value {or the movement (return) start delay of the trunnion 7b toward the neutral position in the axial direction of the tilt shafts 8c, 8c} is large. By measuring the length, it may be detected whether the shoulder 24 of the trunnion 7b is in contact with the side surface of the support plate 10a (10b). Alternatively, the distance D between the shoulder 24 and the side surface of the support plate 10a (10b) is estimated by estimating the inclination angle of the support plate 10a (10b) with respect to the horizontal direction from the operating state of the toroidal type continuously variable transmission. It is also possible to determine whether is equal to or less than a predetermined value α. That is, for example, as shown in FIG. 4B, when the speed ratio of the toroidal continuously variable transmission is repeatedly changed from a constant speed state to only one side (deceleration side in the illustrated example), the support plate 10a ( 10b) is inclined with respect to the horizontal direction, and the distance D between the shoulder 24 of the trunnion 7b and the side surface of the support plate 10a (10b) is reduced. Therefore, by estimating the inclination angle of the support plate 10a (10b) with respect to the horizontal direction based on the operating state (shift pattern) of the toroidal continuously variable transmission, the shoulder 24 of the trunnion 7b and the support plate 10a ( The distance D from the side surface 10b) can be estimated.

  In any case, if it is determined in step 1 that the distance D between the at least one facing portion is not more than the predetermined value α (D ≦ α), in the next step 2, the shift lever is not driven. It is determined whether or not the state (P range or N range) is selected. When it is determined that the shift lever is selected in the non-running state, the process proceeds to the next step 3. In step 3, the gear ratio of the toroidal continuously variable transmission is changed in a direction to return the inclinations of the support plates 10a and 10b to their original positions. That is, when the both support plates 10a and 10b are inclined by repeatedly changing the transmission ratio of the toroidal continuously variable transmission from the constant speed state to the deceleration side, the toroidal continuously variable transmission. Is changed to the speed increasing side. On the other hand, when both the support plates 10a and 10b are inclined by repeatedly changing the transmission ratio of the toroidal type continuously variable transmission from the constant speed state to the speed increasing side, the toroidal type continuously variable transmission. Change the gear ratio of the machine to the deceleration side. In any case, after the inclinations of the two support plates 10a and 10b are returned to their original positions (horizontal state), the process ends (returns to the start).

On the other hand, if it is determined in step 2 that the shift lever is selected to be in the traveling state (D range or R range), the process proceeds to step 4 and the magnitude of the pressing force generated by the pressing device. As a traction coefficient μ used for calculation to determine the calculation in a normal state (the distance D is larger than a predetermined value α, that is, the support plates 10a and 10b are horizontal or in the vicinity thereof). Is set to a value μ _L (<μ ₀ ) that is smaller than the value μ ₀ used for the control, and then the gear ratio control is executed.

On the other hand, in the step 1, among the facing portions between the shoulder portions 24, 24 of the trunnions 7b, 7b and the side surfaces of the support plates 10a, 10b, the distance D between all the facing portions is greater than the predetermined value α. Is determined to be larger (D> α), the process proceeds to step 5 and the value used in the normal state as the traction coefficient μ (the same value as the traction coefficient used in the conventional gear ratio control) μ ₀ is set. After setting and executing the gear ratio control, the process ends (returns to the start).

According to the toroidal type continuously variable transmission of this example as described above, the pair of support plates 10a and 10b is inclined in accordance with the operation of changing the gear ratio between the disks 2 and 5. In addition, it is possible to prevent an excessive slip (gross slip) from occurring at the rolling contact portion (traction portion) between the inner surface of each of the disks 2 and 5 and the peripheral surface of each of the power rollers 6b and 6b. That is, in the case of the toroidal type continuously variable transmission of the present example, the support plate 10a (10b) is inclined, and the shoulder portions 24, 24 of the trunnions 7b, 7b and the opposing portions of the side surfaces of the support plates 10a, 10b Among them, when the distance D between at least one facing portion is equal to or less than the predetermined value α and the shift lever is selected to be in the non-running state, the inclination of the both support plates 10a and 10b is changed to the original position. The gear ratio of the toroidal continuously variable transmission is controlled in the direction to return to the (horizontal state). Further, when the distance D is equal to or less than the predetermined value α and the shift lever is selected to be in a traveling state, a traction coefficient used for calculation for determining the magnitude of the pressing force generated by the pressing device. as mu, than the value mu ₀ used in the normal state to set a smaller value mu _L. As a result, the pressing force generated by the hydraulic pressing device can be sufficiently increased, and the occurrence of gross slip at each of the traction portions can be prevented. On the other hand, among the facing portions between the shoulder portions 24, 24 of the trunnions 7b, 7b and the side surfaces of the support plates 10a, 10b, the distance D between all the facing portions is larger than the predetermined value α. Since the traction coefficient μ is set to the value μ ₀ used in the normal state and gear ratio control is executed, it is possible to suppress the surface pressure of each traction portion from being excessive, and the toroidal type continuously variable It is possible to prevent the transmission efficiency of the transmission from dropping.

  In the case of this example, the above-described structure can be realized without providing the reinforcing member (upper and lower connecting link) described in Patent Document 5 and the elastic member described in Patent Document 6. Therefore, it is possible to prevent the manufacturing cost of the toroidal type continuously variable transmission from increasing and the toroidal type continuously variable transmission from being increased in size and weight.

[Second Example of Embodiment]
FIG. 5 shows a second example of an embodiment of the present invention corresponding to claim 1. In the case of this example, in step 1a, the distance D between at least one facing portion among the facing portions between the shoulder portions 24, 24 of the trunnions 7b, 7b and the side surfaces of the support plates 10a, 10b (see FIG. 1) is set. When it is determined that it is equal to or less than the predetermined value α (D ≦ α), in the next step 2a, the upper limit value of the input torque to the outer disks 2, 2 (see FIG. 9) as the input side disk is set to the trunnion 7b. Even when the shoulder portion 24 and the side surface of the support plate 10a (10b) are in contact (contact) with each other, the size is such that gross slip does not occur in each traction portion (for example, the support plates 10a and 10b are horizontal). Limited to about 50% of the situation. For this purpose, specifically, the signal representing the accelerator opening is corrected and then input to a controller for calculating the gear ratio of the toroidal-type continuously variable transmission. Alternatively, the engagement pressure of the clutch provided between the drive shaft 14 (see FIG. 9) for rotationally driving the outer disks 2 and 2 and the output shaft of the engine is reduced to cause slippage at the engagement portion of the clutch. You can also make it. That is, the energizing amount to a control valve (solenoid valve) that controls the engagement pressure of the clutch is limited to a predetermined value or less to suppress the engagement pressure.

In the case of this example as described above, even if the shoulder portion 24 of the trunnion 7b and the side surface of the support plate 10a (10b) are in contact with each other, an increase in the pressing force generated by the pressing device is suppressed. However, it is possible to prevent gross slip from occurring in each traction section.
The configuration and operation of the other parts are the same as in the first example of the embodiment described above.

[Third example of embodiment]
FIG. 6 also shows a third example of the embodiment of the invention corresponding to claim 1. In the case of the toroidal-type continuously variable transmission of this example, at step 1b, at least of the facing portions between the shoulder portions 24, 24 of the trunnions 7b, 7b and the side surfaces of the support plates 10a, 10b (see FIG. 1). When it is determined that the distance D between the one opposing portion is equal to or less than the predetermined value α (D ≦ α), in the next step 2b, the upper limit value of the transmission speed of the toroidal continuously variable transmission is set to the normal state ( It is made smaller than the upper limit value of the shift speed when the pair of support plates 10a, 10b is in a horizontal state or a state in the vicinity thereof. That is, when the transmission speed of the toroidal-type continuously variable transmission increases, the amount of heat generated due to side slip in each traction portion increases, and the oil temperature of the lubricating oil in each traction portion increases. As a result, the traction coefficient in each of these traction parts becomes small, and gloss slip is likely to occur in each of these traction parts. Therefore, in the case of this example, the traction coefficient is prevented from being reduced by reducing the upper limit value of the shift speed.
The configuration and operation of the other parts are the same as in the first example of the embodiment described above.

[Fourth Example of Embodiment]
FIG. 7 also shows a fourth example of the embodiment of the invention corresponding to claim 1. In the case of the toroidal-type continuously variable transmission of this example, in step 1c, at least of the facing portions between the shoulder portions 24, 24 of the trunnions 7b, 7b and the side surfaces of the support plates 10a, 10b (see FIG. 1). When it is determined that the distance D between the one opposing portions is equal to or less than the predetermined value α (D ≦ α), the amount of lubricating oil for lubricating each traction portion is increased in the next step 2c. By increasing the amount of lubricating oil, it is possible to suppress an increase in the oil temperature of the lubricating oil in each of these traction portions and to suppress a decrease in the traction coefficient in each of these traction portions. The method for increasing the amount of the lubricating oil is not particularly limited. When the oil pressure of the lubricating oil can be controlled, the oil amount may be adjusted by increasing the oil pressure or providing a flow control valve and controlling the flow control valve.
The configuration and operation of the other parts are the same as in the third example of the embodiment described above.

[Fifth Example of Embodiment]
FIG. 8 also shows a fifth example of the embodiment of the invention corresponding to claim 1. In the case of the toroidal-type continuously variable transmission of this example, in step 1d, at least of the facing portions between the shoulder portions 24, 24 of the trunnions 7b, 7b and the side surfaces of the support plates 10a, 10b (see FIG. 1). If it is determined that the distance D between the facing portions at one location is less than or equal to the predetermined value α (D ≦ α), the next step 2d is to the outer disks 2 and 2 (see FIG. 9), which are the input side disks. Even when the shoulder 24 of the trunnion 7b (see FIG. 1) and the side surface of the support plate 10a (10b) are in contact with each other, the gross slip occurs at each traction portion. Limit the size to not. That is, when the input torque changes abruptly, the hydraulic response delay until the hydraulic pressing device generates the target pressing force increases, and the pressing force generated by the pressing device becomes insufficient. There is a possibility that gross slip occurs in the traction area. In the case of this example, by restricting the speed of change of the input torque, it is possible to prevent the hydraulic response delay from becoming large, and to prevent the occurrence of gross slip in each traction section. The method for limiting the speed of change of the input torque is not particularly limited. For example, after correcting the signal representing the accelerator opening, the signal is input to a controller that calculates the gear ratio of the toroidal continuously variable transmission. I can do it.
The configuration and operation of the other parts are the same as in the second example of the embodiment described above.

  When practicing the present invention, the above-described embodiments can be combined.

DESCRIPTION OF SYMBOLS 1 Rotating shaft 2 Outer disk 3 Cylindrical member 4 Gear 5 Inner disk 6, 6a Power roller 7, 7a, 7b Trunnion 8, 8a-8c Tilt axis 9, 9a, 9b Support beam part 10, 10a, 10b Support plate 11 Radial needle bearing 12 Holding hole 13 Outer ring 14 Needle 15, 15a Support shaft 16 Drive shaft 17 Press device 18 Cylindrical convex surface 19 Thrust ball bearing 20 Outer ring 21 Concave portion 22 Radial needle bearing 23 Stepped surface 24 Shoulder portion 25 Convex portions 26a, 26b Displacement Sensor 27 Load sensor 28 Actuator 29 Wall 30 Reinforcement beam 31 Lubricating oil flow path

Claims (3)

At least one pair of discs that are concentric with each other and supported to freely rotate relative to each other in a state in which each side surface in the axial direction is a toroidal curved surface having an arc-shaped cross section,
With respect to the axial direction, a plurality of discs are provided at positions between the axial side surfaces of the respective discs, and swinging displacements centering on the tilting shaft located at a twisted position with respect to the central axis of each disc are freely provided. A support member;
A support plate for supporting the tilt shafts provided at both ends of each of the support members in a state of allowing swinging and axial displacement;
In a toroidal continuously variable transmission comprising a power roller that is rotatably supported by each support member and has a spherical convex surface that is in rolling contact with one axial side surface of each disk.
Among the facing portions between the side surface of the support plate and the end surface of each support member, the operation is performed when the interval between at least one facing portion is equal to or less than a predetermined value, A toroidal continuously variable transmission, characterized by comprising gloss slip prevention means for preventing excessive slippage at a traction portion which is a rolling contact portion with the peripheral surface of each power roller. A hydraulic pressing device that presses the disks in a direction approaching each other with the introduction of hydraulic pressure into the hydraulic chamber,
The gross slip prevention means is used for calculation for determining the magnitude of the pressing force generated by the pressing device with the shift lever for switching the traveling state switched to the traveling state. The value of the coefficient is set to a small value compared to the case where the distance between all the facing portions of the facing portions of the side surface of the support plate and the end surface of each support member is larger than the predetermined value. A toroidal continuously variable transmission according to claim 1.   The gloss slip prevention means changes a gear ratio between the disks in a direction in which a gap between the at least one facing portions is increased in a state in which a shift lever for switching a running state is switched to a non-running state. A toroidal continuously variable transmission according to any one of claims 1 and 2.

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