JP2015206425A - Half-toroidal type continuously variable transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To generate proper pressing force with a simple structure in a half toroidal type continuously variable transmission.SOLUTION: A cam mechanism 18 disposed between a trunnion body 17 and an intermediate member 19, is composed of a first cam face C1 formed on the trunnion body 17, a second cam face C2 formed on the intermediate member 19, and a ball 34 kept into contact with the first cam face C1 and the second cam face C2. As the first and second cam faces C1, C2 are in parallel with each other and inclined to a trunnion axis L1, when a prescribed input torque is input, an input disc 13 and an output disc 14 convert a load for energizing a power roller 23 in a direction of the trunnion axis L1 by tangential force of transmission torque, into pressing force of the power roller 23 by the cam mechanism 18, thus gross slip of the power roller 23 can be prevented. Here, as the cam mechanism 18 generates necessary and sufficient pressing force according to the input torque and ratio, degradation of power transmission efficiency due to excessive pressing force can be prevented.

Description

  The present invention sandwiches an input shaft connected to a drive source, an input disk supported so as not to rotate relative to the input shaft, an output disk supported so as to be rotatable relative to the input shaft, and the input shaft. And a power roller supported by the pair of trunnions and clamped between the input disk and the output disk.

  The half-toroidal continuously variable transmission, which changes the ratio steplessly by tilting the power roller sandwiched between the input disc and output disc, is a traction oil that intervenes at the contact point between the input disc and output disc and the power roller. In order to transmit torque with the traction force obtained by compressing the glass to vitrify, the loader generates a pressing force, which is a load for sandwiching the power roller between the input disk and the output disk, so that the gloss is applied to the contact point. It is necessary to prevent the occurrence of slip. The appropriate pressing force is determined by the input torque and ratio to the half-toroidal continuously variable transmission. However, if the pressing force is insufficient, a gross slip will occur at the contact point and torque transmission will be impossible. If it is excessively large, there is a problem that the spin loss at the contact point and the loss of the bearings at each part increase to lower the power transmission efficiency.

  As a loader of such a half-toroidal continuously variable transmission, one using a hydraulic pressure is known from the following Patent Document 1, and one using a torque cam is known from the following Patent Document 2.

JP 2002-206608 A JP 2005-308166 A

  By the way, a loader using hydraulic pressure has a piston and a cylinder arranged between an input shaft and an input disk, and generates a pressing force by driving the piston with hydraulic pressure. Therefore, the input torque and ratio of the half-toroidal continuously variable transmission are reduced. It is possible to generate an optimal pressing force according to the pressure, but not only the structure of the hydraulic circuit is complicated due to the need for an electric device such as a solenoid valve, but the load of the oil pump increases. There is.

  In addition, a loader using a torque cam has a plurality of rolling elements arranged between a cam surface provided on an input shaft and a cam surface used for an input disk. Although it can be generated, the pressing force cannot be changed in accordance with the ratio. Therefore, depending on the ratio, there is a problem that the pressing force becomes excessive and the power transmission efficiency is lowered.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to generate an appropriate pressing force with a simple structure in a half-toroidal continuously variable transmission.

  In order to achieve the above object, according to the first aspect of the present invention, an input shaft connected to a drive source, an input disk supported so as not to rotate relative to the input shaft, and relative to the input shaft are provided. An output disk rotatably supported, a pair of trunnions arranged so as to sandwich the input shaft, and a power roller supported by the pair of trunnions and sandwiched between the input disk and the output disk. The trunnion is a half-toroidal continuously variable transmission, wherein the trunnion is a trunnion body, an intermediate member that is supported so as to be movable in the trunnion axis direction with respect to the trunnion body, and the power roller is rotatable on the intermediate member. A cam roller disposed between the trunnion body and the intermediate member; Comprises a first cam surface formed on the trunnion body, a second cam surface formed on the intermediate member, and a rolling element in contact with the first cam surface and the second cam surface. A half-toroidal continuously variable transmission is proposed in which the first and second cam surfaces are parallel to each other and inclined with respect to the trunnion axis.

  According to the second aspect of the invention, in addition to the configuration of the first aspect, the direction connecting the contact point where the power roller contacts the input disk or the output disk and the trunnion axis is the power roller axis. Tan α = M ÷ cos θ is satisfied, where θ is the angle formed with respect to the trunnion axis and α is the angle between the first and second cam surfaces and the traction coefficient of the contact point is M. A characteristic half-toroidal continuously variable transmission is proposed.

  According to a third aspect of the present invention, in addition to the configuration of the first aspect, the direction connecting the contact point where the power roller contacts the input disk or the output disk and the trunnion axis is the power roller axis. An angle formed with respect to the trunnion axis is defined as θ, an angle formed by the first and second cam surfaces with respect to the trunnion axis, a traction coefficient of the contact point as M, and a predetermined safety factor for the transmission force at the contact point. A half-toroidal continuously variable transmission is proposed in which tan α = M ÷ cos θ ÷ Sf is established when Sf (Sf> 1).

  According to the invention described in claim 4, in addition to the configuration of any one of claims 1 to 3, a plurality of the cam mechanisms are arranged in the trunnion axis direction, and the trunnion axis line is arranged. A half-toroidal continuously variable transmission is proposed, which is arranged in a plurality in the sandwiching direction.

  In addition, the ball | bowl 34 of embodiment respond | corresponds to the rolling element of this invention.

  According to the configuration of claim 1, the half-toroidal continuously variable transmission includes an input shaft connected to a drive source, an input disk supported so as not to rotate relative to the input shaft, and supported relative to the input shaft so as to be relatively rotatable. And a pair of trunnions arranged so as to sandwich the input shaft, and a power roller supported by the pair of trunnions and sandwiched between the input disk and the output disk.

  The trunnion includes a trunnion body, an intermediate member that is supported so as to be movable in the trunnion axis direction with respect to the trunnion body, a power roller support member that rotatably and swingably supports a power roller on the intermediate member, a trunnion body, A cam mechanism disposed between the intermediate members, the cam mechanism including a first cam surface formed on the trunnion body, a second cam surface formed on the intermediate member, a first cam surface, and a second cam surface. Since the first and second cam surfaces are parallel to each other and are inclined with respect to the trunnion axis, the input disk and the output disk receive the transmission torque when a predetermined input torque is input. The load that urges the power roller in the trunnion axial direction due to the tangential force component is converted to the pressing force of the power roller by the cam mechanism, and the power roller is the input disk. Rui can be prevented from gross slip with respect to the output disc. At this time, the cam mechanism generates a necessary and sufficient pressing force according to the input torque and the ratio, so that it is possible to prevent a decrease in power transmission efficiency due to an excessive pressing force.

  In addition, since an electric device such as a solenoid valve required for a conventional loader using hydraulic pressure is unnecessary, not only can the structure of the hydraulic circuit of the half-toroidal continuously variable transmission be simplified, but also an oil pump that generates hydraulic pressure can be used. The load can be reduced. Moreover, as compared with the conventional loader in which the torque cam mechanism is disposed between the input shaft and the input disk, the dimension in the input axis direction of the half toroidal continuously variable transmission can be reduced by eliminating the torque cam mechanism. .

  According to the second aspect of the present invention, the angle between the contact point where the power roller contacts the input disk or the output disk and the trunnion axis with respect to the power roller axis is θ, and the first and second cam surfaces Is α and the contact point traction coefficient is M, tan α = M ÷ cos θ holds, so that the pressing force generated by the cam mechanism can prevent the gloss slip of the power roller. It is possible to match the pressing force with higher accuracy.

  According to the third aspect of the present invention, the angle between the contact point where the power roller contacts the input disk or the output disk and the trunnion axis with respect to the power roller axis is θ, and the first and second cam surfaces Is α, the traction coefficient of the contact point is M, and the predetermined safety factor for the transmission force at the contact point is Sf (Sf> 1), tan α = M ÷ cos θ ÷ Sf is Therefore, the pressing force generated by the cam mechanism can be set to a magnitude obtained by multiplying the pressing force that can prevent the gloss slip of the power roller by a predetermined safety factor.

  According to the fourth aspect of the present invention, a plurality of cam mechanisms are arranged in the direction of the trunnion axis, and a plurality of cam mechanisms are arranged in the direction sandwiching the trunnion axis, so that the pressing force transmitted from the trunnion body to the intermediate member is generated. By sharing and supporting by a plurality of cam mechanisms, the posture of the intermediate member can be stabilized.

Sectional drawing of the direction orthogonal to the input shaft of a half toroidal type continuously variable transmission. FIG. 2 is a sectional view taken along line 2-2 in FIG. 1. The perspective view of a trunnion and a power roller. The perspective view of a trunnion. FIG. FIG. 6 is a sectional view taken along line 6-6 of FIG. The principal part enlarged view of FIG. FIG. The graph explaining the effect of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

  As shown in FIGS. 1 and 2, the single cavity half-toroidal continuously variable transmission T includes an input shaft 12 that is rotatably supported by a casing 11 and connected to a drive source (not shown). A substantially cone-shaped input disk 13 is fixed to the input shaft 12, and a substantially cone-shaped output disk 14 is supported via a bearing 15 so as to be relatively rotatable. A pair of trunnions 16, 16 are arranged in the casing 11 so as to sandwich the input shaft 12. Each trunnion 16 includes a trunnion body 17 formed in a crank shape, and four cam mechanisms 18 in the trunnion body 17. The intermediate member 19 is supported via the intermediate member 19, and the power roller support member 20 is supported by the intermediate member 19 so as to be swingable. A power roller 23 is rotatably supported on the power roller support member 20 via a thrust bearing 21 and a radial bearing 22, and the power roller 23 abuts on the toroidal surfaces facing the input disk 13 and the output disk 14.

  A hydraulic actuator 26 for driving each trunnion 16 in the direction of the trunnion axis L1 is disposed in a hydraulic control block 25 coupled to the casing 11. The hydraulic actuator 26 includes a piston 27 provided in the trunnion body 17, a cylinder 28 in which the piston 27 is slidably fitted, a speed increasing oil chamber 29 partitioned on one side of the piston 27, and a piston 27. And a speed reducing oil chamber 29 and a speed reducing oil chamber 30 so that a differential pressure acts on the speed increasing oil chamber 29 and the speed reducing oil chamber 30 so that the pair of trunnion bodies 17 and 17 are trunnions. Driven in directions opposite to each other along the direction of the axis L1.

  The upper and lower portions of the pair of trunnion bodies 17 and 17 are pivotally supported by both end portions of the upper link 32 and the lower link 33 through spherical joints 31... When the trunnion body 17 moves downward, the movement is synchronized.

  3-6, the flat surface 17a formed on the trunnion body 17 is provided with a guide protrusion 17b extending linearly in the direction of the trunnion axis L1, and the flat surface of the intermediate member 19 is provided on the guide protrusion 17b. A linear guide groove 19b formed in 19a is slidably fitted. Each of the four cam mechanisms 18 has a recess 17c formed on the flat surface 17a of the trunnion body 17, a recess 19c formed on the flat surface 19a of the intermediate member 19, and a ball 34 sandwiched between the recesses 17c and 19c. It consists of.

  The intermediate member 19 includes an arcuate surface 19d formed on the opposite side of the flat surface 19a, and an arcuate guide protrusion 19e is provided on the arcuate surface 19d. On the other hand, the power roller support member 20 is provided with an arcuate guide groove 20a slidably fitted to the guide protrusion 19e of the intermediate member 19, and the power roller support member 20 is formed by the guide protrusion 19e and the guide groove 20a. The trunnion body 17 is supported to be swingable.

  As shown in FIG. 8 in an enlarged manner, the recess 17c of the trunnion body 17 and the recess 19c of the intermediate member 19 are first and second parallel to each other and inclined at an angle α with respect to the trunnion axis L1. Cam surfaces C1 and C2 are formed, and the ball 34 comes into contact with the first and second cam surfaces C1 and C2.

  Next, the operation of the embodiment of the present invention having the above configuration will be described.

  First, the shifting action of the half toroidal type continuously variable transmission T will be described. When the pair of trunnions 16, 16 are driven in the opposite directions along the trunnion axis L 1 by the hydraulic actuators 26, 26, the trunnion bodies 17, 17 are caused by reaction forces that the power rollers 23, 23 receive from the input disk 13 and the output disk 14. Rotates around the trunnion axis L1, so that the contact point of the power rollers 23, 23 with the input disk 13 moves radially outward with respect to the input shaft 12, and the contact point with the output disk 14 changes to the input shaft 12. Therefore, the rotation of the input disk 13 is increased and transmitted to the output disk 14, and the ratio of the half-toroidal continuously variable transmission T is continuously reduced.

  On the other hand, when the pair of trunnions 16 and 16 are driven along the trunnion axis L1 in the opposite direction, the contact point of the power rollers 23 and 23 with the input disk 13 moves radially inward with respect to the input shaft 12. At the same time, since the contact point with the output disk 14 moves radially outward with respect to the input shaft 12, the rotation of the input disk 13 is decelerated and transmitted to the output disk 14, and the ratio of the half-toroidal continuously variable transmission T Increases continuously.

  Next, the operation of the cam mechanism 18 will be described based on FIG. 5, FIG. 6, and FIG.

  When a predetermined input torque is input to the input shaft 12 of the half toroidal type continuously variable transmission T, for example, one power roller 23 receives a downward torque transmission tangential force Ft from a contact point with the input disk 13 and outputs the output disk. 14 receives a downward torque transmission tangential force Ft from the point of contact with 14 (see FIG. 5). As a result, the trunnion 16 that supports the power roller 23 is biased downward by a load of 2 Ft, and the downward load of 2 Ft is supported by an upward load of 2 Ft generated by the hydraulic actuator 26. At this time, the trunnion 16 biased upward and the intermediate member 19 integrated with the power roller 23 biased downward move relatively in the direction of the trunnion axis L1 with a load of 2 Ft (see FIG. 6B). (See arrows A and B).

FIG. 8 is an enlarged view of the cam mechanism 18 to which a load of 2 Ft is input. Since the load of 2 Ft is equally shared by the four cam mechanisms 18, the contact point P 1 between the first cam surface C 1 on the trunnion 16 side of the one cam mechanism 18 and the ball 34 is
F1 = 2Ft ÷ 4 = Ft / 2 (1)
Is applied in the direction of the trunnion axis L1. Since the first cam surface C1 is inclined at the angle α, the load F2 with which the first cam surface C1 presses the ball 34 is
F2 = F1 ÷ sin α = (Ft / 2) ÷ sin α (2)
The ball 34 presses the second cam surface C2 on the intermediate member 19 side by F2 = (Ft / 2) ÷ sin α. Since the second cam surface C2 is inclined by the angle α, the load F3 in the direction of the power roller axis L2 that the intermediate member 19 receives at the contact point P2 with the ball 34 is:
F3 = F2 × cos α = (Ft / 2) ÷ tan α (3)
It becomes. That is, one cam mechanism 18 presses the power roller 23 in the direction of the power roller axis L2 with a pressing force of F3 = (Ft / 2) ÷ tan α.

FIG. 7 shows a cross section of the power roller 23 in a direction perpendicular to the trunnion axis L1, and the power roller 23 is in contact with the input disk 13 at the contact point P3 and is in contact with the output disk 14 at the contact point P4. The angle formed between the direction connecting the trunnion axis L1 and the contact point P3 and the power roller axis L2 is θ, and the angle formed between the direction connecting the trunnion axis L1 and the contact point P4 and the power roller axis L2 is also θ. The pressing force by which the four cam mechanisms 18 press the power roller 23 in the direction of the power roller axis L2 is 4 × F3 = 2Ft ÷ tanα. The pressing force presses the input disk 13 at the contact point P3. The pressing force F4 is divided into a pressing force F4 that the power roller 23 presses the output disk 14 at the contact point P4, and these two pressing forces F4 are:
F4 = 4 × F3 ÷ 2 ÷ cos θ = Ft ÷ tan α ÷ cos θ (4)
It is.

The radius from the input axis L3 to the contact point P3 on the input disk 13 side is r1, the input torque input from the drive source to the input shaft 12 is Tin, and the number of cavities of the half-toroidal continuously variable transmission T is N (main Assuming that N = 1 in the embodiment and the number of power rollers 23 is n (n = 2 in this embodiment), the input torque Tin input to the input shaft 12 uses the torque transmission tangential force Ft. ,
Tin = N × n × r1 × Ft (5)
The torque transmission tangential force Ft is given by
Ft = Tin ÷ N ÷ n ÷ r1 (6)
It is represented by

When the equation (6) is substituted into the equation (4), the pressing force F4 that the power roller 23 presses the input disk 13 at the contact point P3 by the cam mechanism 18 is
F4 = Tin ÷ N ÷ n ÷ r1 ÷ tan α ÷ cos θ (7)
It is represented by

On the other hand, when the traction coefficient representing the friction coefficient at the contact point P3 is M, the pressing force F4 ′ of the power roller 23 for preventing the occurrence of gross slip at the contact point P3 is:
F4 ′ = Ft ÷ M = Tin ÷ N ÷ n ÷ r1 ÷ M (8)
Given in.

A pressing force F4 that the power roller 23 presses the input disk 13 at the contact point P3 by the cam mechanism 18 shown in the equation (7), and a power roller that prevents the gloss slip from occurring at the contact point P3 shown in the equation (8). As is clear from the comparison with the pressing force F4 'of 23,
tan α = M ÷ cos θ (9)
If it is set, F4 ′ = F4 is always established, and the cam mechanism 18 can generate a pressing force F4 that does not cause excess or deficiency so that the power roller 23 does not slip grossly against the input disk 13. Moreover, the condition (9), which is the condition for this, is that the angle α between the first cam surface C1 and the second cam surface C2, which are both constants, and the direction connecting the trunnion axis L1 and the contact points P3 and P4 are the power roller axis. It includes only the angle θ formed with L2 and the traction coefficient M and does not include the input torque, but also includes the radius r1 of the contact point P1 and the radius r2 of the contact point P4, that is, the ratio of the half-toroidal continuously variable transmission T. Therefore, an appropriate pressing force F4 can be obtained regardless of the input torque and the ratio.

Similarly, as is clear when comparing Equations (7) and (8),
tan α = M ÷ cos θ ÷ Sf (Sf> 1) (10)
If F4 ′ × Sf = F4 is always established, a force F4 obtained by multiplying the pressing force for preventing the power roller 23 from slipping against the input disk 13 by a predetermined safety factor Sf is applied to the cam mechanism 18. Can be generated. In addition, since the condition for this does not include the input torque and the ratio of the half-toroidal continuously variable transmission T, an appropriate pressing force F4 can be obtained regardless of the input torque and the ratio.

  The pressing force F4 of the contact point P3 on the input disk 13 side has been examined above. Next, the pressing force F4 of the contact point P4 on the output disk 14 side will be examined.

The radius from the input axis L3 of the contact point P4 on the output disk 14 side is r2, and the output torque Tout output from the output disk 14 is i.
Tout = Tin × i (11)
Given in.

The pressing force F4 by which the power roller 23 presses the output disk 14 at the contact point P4 on the output disk 14 side by the cam mechanism 18 is obtained by changing Tin in the equation (7) to Tout and changing r1 to r2.
F4 = Tout ÷ N ÷ n ÷ r2 ÷ tan α ÷ cos θ (12)
Given in. Further, the pressing force F4 ′ of the power roller 23 for preventing the gross slip from occurring at the contact point P4 is obtained by changing the input torque Tin in the equation (8) to the output torque Tout and changing r1 to r2.
F4 ′ = Tout ÷ N ÷ n ÷ r2 ÷ M (13)
Given in.

  As is clear from the comparison between the equations (12) and (13), as shown in the equation (9), if tan α = M ÷ cos θ is set, F4 ′ = F4 is always established, and the cam mechanism 18 causes the power roller 23 to Therefore, it is possible to obtain a pressing force F4 with no excess or deficiency for preventing the output disk 14 from slipping grossly. In addition, since the condition for this does not include the input torque and the ratio of the half-toroidal continuously variable transmission T, an appropriate pressing force F4 can be obtained regardless of the input torque and the ratio.

  Similarly, as is clear from the comparison between the equations (12) and (13), if tan α = M ÷ cos θ ÷ Sf is set as shown in the equation (10), F4 ′ × Sf = F4 is always established. The cam mechanism 18 can generate a force F4 obtained by multiplying the pressing force for preventing the power roller 23 from slipping against the input disk 13 by the safety factor Sf. In addition, since the condition for this does not include the input torque and the ratio of the half-toroidal continuously variable transmission T, an appropriate pressing force F4 can be obtained regardless of the input torque and the ratio.

  The reason why the cam mechanism 18 of this embodiment can generate the pressing force F4 according to the input torque and the ratio is considered as follows.

  That is, when the input torque is doubled with the ratio being constant, the torque transmission tangential force Ft applied to the power roller 23 is also doubled, and the load 2Ft in the direction of the trunnion axis L1 input to the cam mechanism 18 is also doubled. Thus, the pressing force F4 of the power roller 23 generated by the cam mechanism 18 is also doubled.

  When the ratio decreases and the radius r1 from the input axis L3 to the contact point P3 on the input disk 13 side is doubled, for example, when the input torque is constant, the torque transmission tangential force Ft applied to the power roller 23 is 2 minutes. The load 2Ft in the direction of the trunnion axis L1 input to the cam mechanism 18 is also halved, and the pressing force F4 of the power roller 23 generated by the cam mechanism 18 is also halved.

  As described above, even if the input torque or ratio changes, the pressing force of the power roller 23 automatically changes in accordance with the change. Therefore, an appropriate pressing force is applied in all input torque regions and all ratio regions. Can be obtained.

  FIG. 9 is a graph showing how the pressing force with which the power roller 23 presses the input disk 13 at the contact points P3 and P4 changes according to the ratio of the half-toroidal continuously variable transmission T.

  According to the present embodiment, the final pressing force (for example, 1.1) multiplied by the pressing force (see the solid line) for preventing the occurrence of gross slip in the power roller 23 obtained by the equation (8) (see 1.1). The angle α is determined using the equation (10) so that a broken line is obtained. The chain line indicates the pressing force generated by the torque cam mechanism described in Patent Document 2, and this pressing force is excessive in a region where the ratio is small and a region where the ratio is large (see the hatched portion), and the corresponding amount is wasted. There is a problem that the friction is generated and the power transmission efficiency is lowered. However, according to the present embodiment, it is possible to generate a pressing force with no excess or deficiency in all ratio regions, and to avoid a reduction in power transmission efficiency while preventing a gross slip of the power roller 23.

  As described above, according to the present embodiment, when a predetermined input torque is input to the input shaft 12, the input disk 13 and the output disk 14 cause the power roller 23 to move in the direction of the trunnion axis L1 by the tangential force component of the transmission torque. The urging load is converted into a pressing force of the power roller 23 by the cam mechanism 18, and the power roller 23 can be prevented from being grossly slipped with respect to the input disk 13 or the output disk 14. At this time, the cam mechanism 18 generates a necessary and sufficient pressing force in accordance with the input torque and the ratio, so that it is possible to prevent a decrease in power transmission efficiency due to an excessive pressing force.

  Further, since a plurality of cam mechanisms 18 are arranged in the direction of the trunnion axis L1, and a plurality of cam mechanisms 18 are arranged in the direction sandwiching the trunnion axis L1, a pressing force transmitted from the trunnion body 17 to the intermediate member 19 is applied to the plurality of cam mechanisms 18. By supporting and sharing, the posture of the intermediate member 19 can be stabilized. In addition, since an electric device such as a solenoid valve required for a conventional loader using hydraulic pressure is unnecessary, not only can the hydraulic circuit structure of the half-toroidal continuously variable transmission T be simplified, but also an oil pump that generates hydraulic pressure. Can be reduced. Furthermore, compared to the conventional loader in which the torque cam mechanism is arranged between the input shaft and the input disk, the size of the half toroidal continuously variable transmission T in the direction of the input axis L3 is reduced by eliminating the torque cam mechanism. can do.

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.

  For example, the half-toroidal continuously variable transmission T according to the embodiment is a single cavity type, but may be a double cavity type.

12 input shaft 13 input disk 14 output disk 16 trunnion 17 trunnion body 18 cam mechanism 19 intermediate member 20 power roller support member 23 power roller 34 ball (rolling element)
C1 first cam surface C2 second cam surface L1 trunnion axis L2 power roller axis P3 contact point P4 contact point

Claims (4)

An input shaft (12) connected to a drive source, an input disk (13) supported so as not to rotate relative to the input shaft (12), and an output disk supported so as to be rotatable relative to the input shaft (12) (14), a pair of trunnions (16) disposed so as to sandwich the input shaft (12), and the input disk (13) and the output disk (14) supported by the pair of trunnions (16) A half-toroidal continuously variable transmission comprising a power roller (23) sandwiched therebetween,
The trunnion (16) includes a trunnion body (17), an intermediate member (19) supported to be movable in the direction of the trunnion axis (L1) with respect to the trunnion body (17), and the intermediate member (19). A power roller support member (20) that rotatably and swingably supports the power roller (23), and a cam mechanism (18) disposed between the trunnion body (17) and the intermediate member (19). Prepared,
The cam mechanism (18) includes a first cam surface (C1) formed on the trunnion body (17), a second cam surface (C2) formed on the intermediate member (19), and the first cam A rolling element (34) contacting the surface (C1) and the second cam surface (C2), and the first and second cam surfaces (C1, C2) are parallel to each other and have a trunnion axis (L1) A half-toroidal continuously variable transmission that is inclined with respect to   The direction connecting the contact points (P3, P4) where the power roller (23) contacts the input disk (13) or the output disk (14) and the trunnion axis (L1) is relative to the power roller axis (L2). When the angle formed is θ, the angle formed by the first and second cam surfaces (C1, C2) with respect to the trunnion axis (L1) is α, and the traction coefficient of the contact points (P3, P4) is M. The half-toroidal continuously variable transmission according to claim 1, wherein tan α = M ÷ cos θ is established.   The direction connecting the contact points (P3, P4) where the power roller (23) contacts the input disk (13) or the output disk (14) and the trunnion axis (L1) is relative to the power roller axis (L2). The angle formed by θ, the angle formed by the first and second cam surfaces (C1, C2) with respect to the trunnion axis (L1) is α, the traction coefficient of the contact points (P3, P4) is M, The half toroidal according to claim 1, wherein tan α = M ÷ cos θ ÷ Sf is established when a predetermined safety factor for the transmission force at the contact points (P3, P4) is Sf (Sf> 1). Type continuously variable transmission.   A plurality of cam mechanisms (18) are arranged in the direction of the trunnion axis (L1), and a plurality of cam mechanisms (18) are arranged in a direction sandwiching the trunnion axis (L1). The half toroidal continuously variable transmission according to any one of the preceding claims.

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