JPH10267116A - Controller for toridal continuously variable transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To smoothly switch a first power transmission path in a low mode in which a final gear ratio changes in continuously variable stage in a low speed stage side to a second power transmission path in a high mode in which the final gear ratio changes in continuously variable stage in a high sped stage side without generating a shock in a toroidal continuously variable transmission. SOLUTION: A controller for a toroidal continuously variable transmission comprises a control unit 300 which beings to switch first and second power transmission paths when an actual toroidal gear ration obtained from the rotating speed of the output and input disks of a toroidal shift mechanism detected by output and input rotating speed sensors 306 and 307 coincides with a gear ratio upon changing a mode and controls a step motor 251 to set the actual toroidal gear ratio to the gear ratio upon changing the mode during a switching operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toroidal type continuously variable transmission, and more particularly to a control device for a toroidal type continuously variable transmission employing a geared neutral starting system.

[0002]

2. Description of the Related Art As a continuously variable transmission for an automobile, a roller for transmitting power between the input and output disks is interposed between an input disk and an output disk in a pressure-contact state, and the roller is tilted so as to be in contact with both disks. A toroidal-type continuously variable transmission in which the gear ratio of power transmission between both disks is changed steplessly by changing the contact position in the radial direction has been put to practical use.
As disclosed in Japanese Unexamined Patent Application Publication No. 555-555 and Japanese Unexamined Patent Application Publication No. 6-101754, it has been proposed to adopt a start-up system using geared neutral in this type of continuously variable transmission.

In this system, the toroidal transmission mechanism having the above-described configuration is arranged on an input shaft connected to an engine, and a sun gear, an internal gear, and a secondary gear are arranged on a secondary shaft parallel to the input shaft. A planetary gear mechanism having three rotating elements with a pinion carrier that supports a planetary pinion that meshes with both of these gears is arranged. The sun gear is configured to be directly input to the sun gear via the toroidal transmission mechanism.

[0004] By controlling the speed ratio of the toroidal transmission mechanism, the ratio of the rotational speeds input to the pinion carrier and the sun gear of the planetary gear mechanism is controlled to the ratio at which the internal gear, which is the output element, stops. Then, a neutral state is realized, and the speed ratio of the toroidal transmission mechanism is increased or decreased from this state to rotate the internal gear forward or backward.

[0005] According to this method, the vehicle can be started without using a clutch, a torque converter, or the like connected at the time of starting, and the responsiveness and power transmission efficiency at the time of starting are improved.

In this type of continuously variable transmission, by applying these actually measured values to shift characteristics set in advance based on running conditions such as vehicle speed and throttle opening, the engine speed or final gear ratio is determined. Is determined, and the gear ratio of the toroidal transmission mechanism, that is, the tilt angle of the roller is controlled so that the target value is obtained. At this time, the tilt angle of the roller and the final gear ratio are correlated. For this reason, depending on the value of the target final gear ratio, the roller may have to be largely tilted with respect to the disk, which causes a problem such as a reduction in power transmission efficiency.

Therefore, in general, the power transmission path is switched so that the correlation between the roller tilt angle and the final gear ratio is opposite to each other, and the width of the roller tilt angle is limited to a predetermined range. However, it is known to achieve a desired final gear ratio.

For example, a path for transmitting the driving torque of the engine to the driving wheels via the toroidal transmission mechanism and the planetary gear mechanism to realize the above-described geared neutral state is defined as a first transmission path. A path for transmitting the driving torque of the engine to the drive wheels via only the toroidal transmission mechanism without passing through the planetary gear mechanism is defined as a second transmission path. In the first transmission path, the final gear ratio is infinite. From the geared neutral in the forward direction, the final gear ratio decreases (increases) as the transmission ratio of the toroidal transmission mechanism increases (decelerates). On the other hand, in the second transmission path, The final gear ratio decreases (increases) as the speed ratio of the toroidal transmission mechanism decreases (increases in speed).

According to this, considering the case where the final gear ratio is reduced as the vehicle speed increases, for example,
After starting from the geared neutral state on the transmission path, the roller is tilted in a direction in which the speed ratio of the toroidal transmission mechanism increases, and then the transmission path is switched to the second transmission path, and this time, on the contrary, the toroidal transmission mechanism is reversed. The roller is tilted in the opposite direction in the direction in which the gear ratio of the roller becomes smaller, and as a result, the width of the roller tilt angle can be suppressed within a certain range. Failures will be avoided.

[0010]

In this case, the transmission path is switched by changing the final gear ratio or the transmission ratio of the toroidal transmission mechanism in the transmission control (first control mode or low mode) in the first transmission path. When the final gear ratio or the speed ratio of the toroidal transmission mechanism in the speed change control (the second control mode or the high mode) on the second transmission path is different, the power transmission path is switched, in other words, Second
When the control mode is switched, the transmission ratio is suddenly changed and a large shock is generated. Therefore, the transmission paths are switched between the control modes at the point where the transmission ratio becomes the same.

Therefore, when the mode is switched, since the rotation is synchronized between the input side and the output side, no shock is theoretically generated by the switching, but actually, the transmission path is not changed. Since it takes time to engage and disengage the switching clutch, changes in vehicle speed and throttle opening during that time cause the rotation to be out of synchronization at the end of transmission path switching, resulting in a shock due to a sudden change in gear ratio. Will do.

SUMMARY OF THE INVENTION The present invention addresses the above-mentioned problems in a toroidal-type continuously variable transmission employing a geared neutral start system, and an object of the present invention is to effectively avoid a shock when switching between a low mode and a high mode. And

[0013]

Means for Solving the Problems In order to solve the above problems, the present invention is characterized in that it is configured as follows.

First, in the invention described in claim 1 of the present application (hereinafter referred to as "first invention"), a roller disposed in a press-contact state between an input disk and an output disk is tilted. By using only a toroidal speed change mechanism that changes the gear ratio between the two discs, a first transmission path that transmits the driving torque of the engine to the drive wheels using the toroidal speed change mechanism and the planetary gear mechanism, and a toroidal speed change mechanism. Transmission path switching means for selectively switching the path between the transmission path and the second transmission path, and the toroidal transmission mechanism and the transmission path switching means in accordance with a transmission characteristic set in advance based on a traveling state of the vehicle. Control means for controlling the toroidal-type continuously variable transmission, wherein the control means has the same transmission ratio in the first and second transmission paths. The transmission path switching means is controlled so that the transmission path is switched at a certain point, and the toroidal transmission mechanism is controlled such that the same transmission ratio is maintained while the transmission path is switched by the switching means. It is characterized by the following.

Further, the invention according to claim 2 (hereinafter referred to as “second
Invention ". In the first aspect, the toroidal speed change mechanism has a trunnion that supports the roller,
The roller is tilted by the trunnion receiving the pressure difference between the two hydraulic pressures and moving with respect to the disk, and slides in the valve body as a control valve for adjusting the pressure difference. A three-layer valve having a sleeve slidably housed in the sleeve and a spool slidably housed in the sleeve, wherein the sleeve of the three-layer valve slides in the valve body to provide a toroidal transmission mechanism. The control means fixes the sleeve of the three-layer valve so that the tilt angle of the roller does not change during the switching of the transmission path by the transmission path switching means, so that the first and second valves are fixed. The toroidal transmission mechanism is controlled such that the same transmission ratio is maintained in the two transmission paths.

With the above arrangement, the following effects can be obtained according to the present invention.

First, according to the first aspect of the invention, while the first and second transmission paths are being switched, the toroidal transmission mechanism is controlled such that the same transmission ratio is maintained between the transmission paths. Even if it takes time to switch between the low mode and the high mode and the vehicle speed and the throttle opening change during that time, the rotation is not synchronized at the end of the switching of the mode, and a shock due to a sudden change in the gear ratio is not caused. Is avoided.

According to the second aspect of the present invention, a configuration for maintaining the same speed ratio is further embodied. When the sleeve of the three-layer valve moves, the trunnion moves with respect to the input / output disk and the roller tilts. When the transmission path is switched, the sleeve is fixed so as not to move the trunnion during the switching of the transmission path, so that the inclination angle of the roller does not change, and the first and the second The same gear ratio is maintained between the two control modes.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a mechanical configuration, a hydraulic control circuit configuration, and a specific operation of shift control of a continuously variable transmission according to an embodiment of the present invention will be described.

[0020] Mechanical Configuration FIG. 1 is a skeleton view showing a mechanical structure of the toroidal type continuously variable transmission according to the present embodiment, the transmission 10, the torsional damper 3 to the output shaft 2 of the engine 1 An input shaft (first shaft) 11 connected via
A hollow primary shaft (third shaft) 12 loosely fitted to the outside of the shaft 11;
Secondary shafts (second
Shafts 13), and these shafts 11 to 13
However, both are arranged so as to extend in the lateral direction of the vehicle.

In the continuously variable transmission 10, a toroidal type first and second continuously variable transmission mechanism 2 is provided on the axis of the input shaft 11 and the primary shaft 12.
0, 30 and a loading cam 40, and a planetary gear mechanism 50, a low mode clutch (first clutch mechanism) 60 and a high mode clutch (second clutch) Mechanism) 70 are provided. A low-mode gear train 80 and a high-mode gear train 90 are provided between the axis of the input shaft 11 and the primary shaft 12 and the axis of the secondary shaft 13.

The first and second continuously variable transmission mechanisms 20 and 30 have substantially the same structure, and each of the input and output disks 21 and 31 and the output disk 2 has a toroidal surface.
2 and 32, and both discs 2
Two rollers 23 and 33 for transmitting power between the first and second 22 and the first and second 31, 32, respectively, are provided.

The first continuously variable transmission mechanism 20 arranged farther from the engine 1 has an input disk 21 on the opposite side to the engine and an output disk 22 on the engine side.
The second continuously variable transmission mechanism 30 arranged closer to the engine 1 has an input disk 31 on the engine side and an output disk 32 on the opposite side to the engine side. The 30 input disks 21 and 31 are respectively coupled to both ends of the primary shaft 12, and the output disks 22 and 32 are integrated and rotatably supported by an intermediate portion of the primary shaft 12.

A first gear 81 constituting the low mode gear train 80 is connected to an end of the input shaft 11 on the side opposite to the engine, and the first gear 81 and the first continuously variable transmission mechanism 20 are connected to each other. A loading cam 40 is interposed between the input disk 21 and the output disks 22 and 33 (hereinafter, referred to as an “integrated output disk 34”) integrated with the first and second continuously variable transmission mechanisms 20 and 30. "
) Is provided on the outer periphery of the first gear 91 that constitutes the high-mode gear train 90.

On the other hand, a second gear 82 constituting the low-mode gear train 80 is rotatably supported at an end of the secondary shaft 13 on the side opposite to the engine.
3 and is connected to the first gear 81 via
The planetary gear mechanism 50 is disposed at an intermediate portion of the secondary shaft 13. And, the planetary gear mechanism 50
A low mode clutch 60 for connecting or disconnecting the pinion carrier (third rotating element) 51 and the second gear 82 of the low mode gear train 80 is provided between the pinion carrier 51 and the second gear 82 of the low mode gear train 80.

On the engine side of the planetary gear mechanism 50, a high mode gear train 9 provided on the outer periphery of the integrated output disk 34 of the first and second continuously variable transmission mechanisms 20 and 30 is provided.
A second gear 92 meshing with the first gear 91 is rotatably supported, and the second gear 92 and the sun gear (first rotating element) 52 of the planetary gear mechanism 50 are connected to each other. 50 internal gears (second rotating element)
53 is connected to the secondary shaft 13, and the second gear 92 of the high mode gear train 90 and the secondary shaft 13 are provided on the engine side of the planetary gear mechanism 50.
And a high mode clutch 70 for connecting or disconnecting the clutch.

A differential device 5 is connected to an end of the secondary shaft 13 on the engine side via an output gear train 4 including first and second gears 4a and 4b and an idle gear 4c. Power is transmitted to left and right drive wheels (not shown) from the differential device 5 via drive shafts 6a and 6b extending left and right.

Next, the components of the transmission 10 will be described in detail with reference to FIGS.

First, the first and second continuously variable transmission mechanisms 20,
30 will be described.
30 has substantially the same configuration, as described above, has input disks 21 and 31 whose opposing surfaces are toroidal surfaces, and output disks 22 and 32 (integrated output disk 34). In between, input and output disks 21, 22
Two rollers 23 and 33 for transmitting power between the rollers and between the rollers 31 and 32, respectively, are provided.

Referring to FIG. 3, the first continuously variable transmission mechanism 2
0 is taken as an example, the configuration will be described in more detail. The pair of rollers 23, 23
2 are supported by trunnions 25, 25 via two substantially radially extending shafts 24, 24, respectively, and are substantially horizontally oriented on the opposite sides of the toroidal surfaces of the input and output disks 21, 22 opposite to each other by 180 °. The disks are vertically arranged in parallel, and are in contact with the toroidal surfaces of the discs 21 and 22 at two positions on the opposite side of the peripheral surface by 180 °.

The trunnions 25, 25 are connected to left and right support members 26,
26, and is rotated about a horizontal axis X, X in the tangential direction of the two disks 21, 22 and orthogonal to the shafts 24, 24 of the rollers 23, 23.
A linear reciprocating motion in the X direction is enabled. Rods 27, 27 extending to one side along the axes X, X are connected to the trunnions 25, 25, and the rods 27, 27 are provided on the side surface of the transmission case 100. 27 and the transmission control unit 11 for tilting the rollers 23, 23 via the trunnions 25, 25.
0 is attached.

The shift control unit 110 has a hydraulic control unit 111 and a trunnion drive unit 112,
The trunnion driving section 112 includes a piston 113 _1, 114 ₁ of the attached increasing speed and deceleration with the first trunnion 25 ₁ of the rod 27 located above, the second trunnion 25 ₂ rods located below 27 Pistons 113 ₂ , 114 ₂ also mounted on
Bets are placed, the upper piston 113 _1, 114 ₁ of opposing a speed increasing on the surface side and the deceleration hydraulic chambers 115 _1,
116 _{1 also} has a speed-increasing and deceleration hydraulic chamber 115 on the opposing surfaces of the lower pistons 113 ₂ and 114 _2.
2, 116 _2, respectively.

The first trunnion 25 located above
_With respect to ₁ , the speed-increasing hydraulic chamber 115 ₁ is disposed on the roller 23 side, and the deceleration hydraulic chamber 116 ₁ is disposed on the opposite side of the roller 23, and the second trunnion 25 located below is disposed.
For _2, speed increasing hydraulic chamber 115 ₂ in a counter roller 23 side, the deceleration hydraulic chamber 116 ₁ is arranged on the roller 23 side.

[0034] Then, the speed increase hydraulic P _H generated by the hydraulic control unit 111, through the oil passage 117, the hydraulic pressure chamber for increasing speed of the first trunnion 25 ₁ is located above 11
5 ₁ and the speed increasing hydraulic chamber 115 _{2 of} the second trunnion 25 ₂ located below.
Decelerating hydraulic P _L generated by 11, via an oil passage (not shown), a speed reduction hydraulic chamber 116 of the _first trunnion 25 ₁ is located above, the second trunnion located below 25 ₂
It is supplied to a speed reduction hydraulic chambers 116 _2.

The relationship between the supply control of the speed-increasing and deceleration hydraulic pressures P _H and P _L and the shifting operation of the continuously variable transmission mechanism 20 will be briefly described taking the first continuously variable transmission mechanism 20 as an example. .

Firstly, by the operation of the hydraulic control unit 111 shown in FIG. 3, first, second trunnions 25 _1, 25 speed increasing hydraulic chamber 115 ₁ of _2, 115 hydraulic P _H for speed increase, which is supplied to the ₂
But first, becomes relatively higher than the predetermined neutral condition relative to the second trunnion 25 _1, 25 deceleration hydraulic chamber 116 ₁ of _2, 116 ₂ to the supply has been decelerated hydraulic P _L has, above the first 1 trunnion 25 ₁ is on the drawing, to the right, the second trunnion 25 ₂ lower will be respectively the left moves horizontally.

At this time, the output disk 2 shown in FIG.
When 2 is assumed to rotate in the x-direction, the first roller 23 ₁ upward, output disk 2 by the movement to the right
2 receives a downward force, and receives an upward force from the input disk 21 which is on the near side of the drawing and is rotating in the anti-x direction. In addition, the lower second roller 23
₂ receives an upward force from the output disk 22 and a downward force from the input disk 21 by moving to the left. As a result, the upper and lower rollers 23 ₁ , 2
3 ₂ both the outer contact position in the radial direction of the input disk 21, the contact position between the output disk 22 to tilt to move radially inward, the speed ratio of the continuously variable transmission mechanism 20 is small (Speed increase).

Further, contrary to the above, first, second trunnions 25 _1, 25 deceleration hydraulic chamber 116 ₁ of _2, 116 deceleration hydraulic P _{L 2} is supplied to the first, second trunnions 2
5 _1, 25 speed increasing hydraulic chamber 115 ₁ of _2, 115 becomes relatively higher than the predetermined neutral condition relative to the speed increase hydraulic P _{L 2} is supplied to, over the first trunnion 25 ₁ is drawings on the left side, the second trunnion 25 ₂ lower respectively horizontally moved to the right.

[0039] At this time, the upward force the first roller 23 ₁ upward from the output disk 22, receives a downward force from the input disk 21, and the second roller 23 of the lower ₂
Receives a downward force from the output disk 22 and an upward force from the input disk 21. As a result, the upper and lower rollers 23 _1, 23 ₂ both the inner contact position in the radial direction of the input disk 21, the contact position between the output disk 22 is tilted so as to move outward in a radial direction, the Mu The speed ratio of the step transmission mechanism 20 increases (deceleration).

The operation of supplying the speed increasing and decelerating oil pressures P _H and P _L by the oil pressure control unit 111 will be described in detail in the explanation of the oil pressure control circuit described later.

The structure and operation of the first continuously variable transmission mechanism 20 are the same as those of the second continuously variable transmission mechanism 30.

As shown in FIG. 2, the input discs 21 and 31 of the first and second continuously variable transmission mechanisms 20 and 30 are provided at both ends of the hollow primary shaft 12 loosely fitted on the input shaft 11. Are spline-fitted so that these input disks 21 and 31 always rotate the same, and as described above, the output disks 22 and 32 of both continuously variable transmission mechanisms 20 and 30 are integrated. Therefore, the rotational speeds on the output side of both the continuously variable transmission mechanisms 20 and 30 are always the same. In association with this, the first and the second by the tilt control of the rollers 23 and 33 as described above.
The control of the speed ratio of the continuously variable transmission mechanisms 20 and 30 is also performed such that the speed ratio is always kept the same.

Here, as shown in an enlarged manner in FIG. 4, the outer peripheral surface of the integrated output disk 34 is provided with a high mode gear train 9.
A first gear 91 formed in a ring shape of 0 is fitted and fixed by welding. In this case, on one side of the integrated output disk 34, the outer periphery of the disk 34 and the first gear 91 are fixed. A counterbore Y is provided over the inner periphery of the gear 91, and the disk 34 and the gear 91 are welded in the counterbore Y.

Therefore, even if the welding metal Z rises from the welding surface during welding, this does not interfere with the toroidal surface 34a on the one side surface, and the roller can be tilted over a wide range. Becomes Further, since the first gear 91 is fixed to the outer periphery of the integrated output gear 34 by welding as described above, the backlash in the axial direction of the first gear 91 is suppressed, and the support thereof is stabilized. Become.

On the other hand, as shown in FIGS. 5 and 6, the loading cam 40 is connected to the first
It has a cam disk 41 interposed between the gear 81 and the input disk 21 of the first continuously variable transmission mechanism 20, and the surfaces of the cam disk 41 and the input disk 21 facing each other are repeatedly uneven in the circumferential direction. As a cam surface, a plurality of rollers 43... 43 held on a retainer disk 42 are arranged between these cam surfaces.

The cam disc 41 is provided with a plurality of pin members 44... 44 arranged in the axial direction on the first gear 81 of the low mode gear train 80 spline-fitted to the end of the input shaft 11 on the side opposite to the engine. 6, and a disc spring 45, between the cam disc 41 and the flange portion 12a provided on the primary shaft 12, as shown in FIG.
45, a needle thrust bearing 46, and its bearing race 47 are interposed.
The cam disk 41 is pressed toward the input disk 21 by the spring forces of 5 and 45.

Thus, the rollers 43... 43 are formed in the concave portions 21 a, 41 a of the cam surfaces of the disks 21, 41.
Between the input shaft 11 and the cam disk 41 via the first gear 81 of the low mode gear train 80.
Is transmitted to the input disk 21 of the first continuously variable transmission mechanism 20, and further transmitted to the input disk 31 of the second continuously variable transmission mechanism 30 via the primary shaft 12.

In particular, as shown by the chain line in FIG.
The rollers 43... 43 roll from the concave portions 21 a and 41 a of the cam surfaces of the discs 21 and 41 toward the convex portions 21 b and 41 b according to the magnitude of the input torque and bite between these cam surfaces. As a result, the input disk 21, the roller 23, the integrated output disk 34 of the first continuously variable transmission mechanism 30 and the roller 33 of the second continuously variable transmission mechanism 30 are sequentially moved to the input disk 31 side of the second continuously variable transmission mechanism 30. Press. Thereby, the first and second continuously variable transmission mechanisms 20, 3
The clamping pressure of the rollers 23 and 33 at 0 is automatically adjusted according to the input torque.

In the loading cam 40, the pin members 44... 44 connecting the cam disk 41 and the first gear 81 of the low mode gear train 80 are formed by convex portions on the cam disk 41 where the wall pressure is increased. 41b
.., 41b. Therefore, the overall thickness of the cam disc 41 is made unnecessarily thick to increase its axial dimension, or the pin members 44.
And the recesses 41a... 41a of the cam surface come close to each other to prevent the strength of the cam disk 41 from being reduced.

Further, according to FIG. 6, the primary shaft 12 loosely fitted to the outside of the input shaft 11
In the description of the support structure, the end of the primary shaft 12 on the engine side is supported by the transmission case 100 via a bearing 131. On the other hand, the end of the primary shaft 12 on the opposite side to the engine is the 1 gear 8
1 is spline-fitted, and the gear 81
2, and is supported by a cover 101 on the side opposite to the engine of the transmission case 100.

The first gear 81 is provided between the first gear 81 and the flange 12a of the primary shaft 12 for supporting the disc springs 45 of the loading cam 40.
The primary shaft 12 and the first shaft 12 are connected to each other through a needle thrust bearing 133 and a bearing race 134.
Disc spring 13 for urging gear 81 in a direction away from each other
5 are arranged.

Therefore, when the primary shaft 12 expands and contracts due to thermal expansion or the like, the end of the shaft 12 on the engine side cannot move in the axial direction.
The end on the opposite side to the engine that is spline-fitted to the shaft is displaced in the axial direction. At this time, the displacement is absorbed by the disc spring 135 and the first gear 81 is displaced.
Is always pressed against the bearing 132 by an appropriate force corresponding to the spring force of the disc spring 135. Therefore,
The first gear 81 is strongly pressed against the bearing 132 by the extension of the primary shaft 12, or conversely, the first gear 8 is compressed by the contraction of the primary shaft 12.
A state in which 1 rattles in the axial direction is avoided.

The bearings 131 and 13 on the engine side and on the opposite side to the engine receive the spring force of the disc spring 135 via the primary shaft 12 and the first gear 81.
2, a moderate axial force is always applied. Particularly, when these bearings 131 and 132 are tapered roller type thrust bearings as shown in the drawing, the axial preload is appropriately maintained. Therefore, problems such as rattling when this is too small and increase in rotational resistance when this is too large are prevented.

An oil pump 102 is attached to the non-engine side cover 101, and the first low-speed gear train 80 which rotates integrally with the input shaft 11 is provided.
It is designed to be driven by a gear 81.

Next, referring to FIG.
3 and the configuration of the planetary gear mechanism 50, the low mode clutch 60, the high mode clutch 70, etc. on the shaft 13 will be described.

The end of the secondary shaft 13 on the engine side is the engine side cover 10 of the transmission case 100.
3, the end opposite to the engine side is the cover 1 opposite to the engine side.
01 is rotatably supported via bearings 141 and 142, respectively. A second gear 92 constituting the high-mode gear train 90 is disposed at the center of the secondary shaft 13, and the planetary gear mechanism 50 is arranged adjacent to and behind the second gear 92 (opposite the engine side, the same applies hereinafter).
And the second gear 92 is connected to the sun gear 52 of the planetary gear mechanism 50. At the rear, a flange member 54 connected to the internal gear 53 of the planetary gear mechanism 50 is spline-fitted to the secondary shaft 13.

Further, a low mode clutch 60 is disposed behind the planetary gear mechanism 50. This clutch 6
0 is rotatably supported by the secondary shaft 13,
Also, a drum member 61 to which the second gear 82 of the low-mode gear train 80 is fixed, and a hub disposed radially inside and connected to the pinion carrier 51 of the planetary gear mechanism 50 via a flange member 55 Member 6
2, a plurality of clutch plates 63... 63 alternately splined with these, and a piston 64 disposed inside the drum member 61.

A space between the piston 64 and the drum member 61 at the back of the piston 64 is defined as a hydraulic chamber 65.
When the engagement hydraulic pressure generated by the clutch control unit 120 shown in FIG. 3 is supplied, the piston 64 strokes forward (toward the engine side, the same applies hereinafter) against the spring 66, so that the clutch plates 63. Is connected to the second gear 82 of the low mode gear train 80 and the planetary gear mechanism 50 via the clutch 60.
Is connected to the pinion carrier 51.

A balance piston 67 is disposed on the front side of the piston 64, and the lubricating oil is introduced into a balance chamber 68 provided between the pistons 64, 67, whereby the operation in the hydraulic chamber 65 is performed. The pressure acting on the piston 65 is offset by the centrifugal force acting on the oil.

A high mode clutch 70 is disposed in front of the second gear 92 of the high mode gear train 90. This clutch 70 is also used for the secondary shaft 13
A drum member 71 coupled via a parking mechanism gear 4d to a first gear 4a of an output gear train 4 spline-fitted to
A hub member 72 connected to the gear 92 and a plurality of clutch plates 73 alternately splined to the hub member 72.
73, and a piston 74 disposed inside the drum member 71.

When the engagement hydraulic pressure generated by the clutch control unit 120 is supplied to a hydraulic chamber 75 provided at the back of the piston 74,
.. 73 are tightened by the rearward stroke against the spring 76, whereby the second gear 92 of the high mode gear train 90 and the secondary shaft 13 or An output gear train 4 spline-coupled to the shaft 13
And the first gear 4a.

The high mode clutch 70 also has
A balance piston 77 is provided behind the piston 74, and lubricating oil is introduced into the balance chamber 78 between the pistons 74, 77, and acts on the piston 74 by centrifugal force acting on hydraulic oil in the hydraulic chamber 75. It is designed to offset pressure.

On the other hand, the end of the secondary shaft 13 on the side opposite to the engine is provided with a recess 13 extending axially forward from the end face.
a boss 101a provided on the anti-engine side cover 101 and protruding forward is fitted into the recess 13a so as to be relatively rotatable. The engine-side cover 103 is also provided with a boss 103a projecting rearward, and is fitted in a recess 13b at the front end of the secondary shaft 13 so as to be relatively rotatable.

The two clutch engagement oil passages 15 for the low mode clutch 60 and the high mode clutch 70 are provided on the boss 101a of the opposite engine side cover 101.
1, 161 are bored in the axial direction, and the clutch control unit
Oil passages 152 and 162 that pass through the inside and are guided upward are connected to these clutch engagement oil passages 151 and 161, respectively.

Of these oil passages, the oil passage 151 for the low mode clutch 60 is provided on the opposite side of the engine-side cover 1.
01 of the boss 101a in the radial direction.
3. A circumferential groove 15 provided on the outer peripheral surface of the boss 101a
4. A radial through hole 1 formed in the peripheral wall of the concave portion 13a of the secondary shaft 13 fitted to the boss portion 101a.
55, a circumferential groove 156 provided on the outer peripheral surface of the shaft 13
And drum member 61 in low mode clutch 60
Of the clutch 6 through a through hole 157 provided in the boss portion of the clutch 6.
0 hydraulic chamber 65. Thus, the low mode clutch engagement hydraulic pressure generated by the clutch control unit 120 is supplied to the hydraulic chamber 65 of the clutch 60.

The oil passage 1 for the high mode clutch 70
Numeral 61 is open at the front end face of the boss 101a, and communicates with a space 163 between the front end face of the boss and the inner end face of the recess 13a of the secondary shaft 13. Further, an oil passage 164 which is bored in the secondary shaft 13 in the axial direction and whose rear end is opened at the inner end surface of the concave portion 13a.
And the hydraulic chamber 75 of the high mode clutch 70 via radial through holes 165 and 166 provided in the secondary shaft 13 and the first gear 4 a of the output gear train 4, respectively. Thus, the high mode clutch engagement hydraulic pressure generated by the clutch control unit 120 is supplied to the hydraulic chamber 75 of the clutch 70.

As described above, the engagement oil passages 151 and 16 for the low mode clutch 60 and the high mode clutch 70 are provided.
1 are guided from the non-engine side cover 101 side where the oil pump 102 is provided, and the hydraulic chambers 65, 70 of the clutches 60, 70 via the secondary shaft 13.
75, the oil pressure is supplied to the hydraulic chambers 65 and 75 more quickly than in the case where one oil path is led from the engine-side cover 103, for example. Responsiveness of the engagement control is improved.

An oil passage 171 is also provided in the boss portion 103a of the engine side cover 103, and an oil passage 172 is guided from the clutch control unit 120 through the cover 103 and upward (see FIG. 2). It is connected to the.
The lubricating oil passage 1 extends in the axial direction from the recess 13b at the front end of the secondary shaft 13 fitted to the boss 103a, and has a rear end closed by a plug 173.
74 and the secondary shaft 1
3 are provided with a plurality of radial through holes 175... 175 communicating with the oil passage 174. Thus, the lubricating oil supplied from the clutch control unit 120 is supplied to the balance chambers 68 and 78 in the low mode clutch 60 and the high mode clutch 70 and other lubricating parts.

As shown in FIG. 3, a transmission control unit 110 is provided on the side of the transmission case 100, and a clutch control unit 120 for controlling the low mode clutch 60 and the high mode clutch 70 is provided below. Although the control unit is divided in this way, the control unit is divided, and one of the control units is attached to the side of the transmission case 100 and the other is attached to the lower portion. The amount of downward projection from the transmission case is smaller than when the transmission case is mounted on the lower part. Therefore, it is advantageous in securing the minimum ground clearance of the vehicle.

As described above, the transmission control unit 1
10 is one side of the transmission case 100 (the left side in FIG. 3).
And the upper and lower rods 27, 27 extending horizontally from the trunnion drive unit 112 of the unit 110 toward the inside of the transmission case 100.
5 and 25 respectively, and these trunnions 2
5 and 25 are operated along the horizontal axis X, X, so that the trunnion drive unit is arranged at the upper part of the transmission case as in the case of operating the trunnion in the vertical direction. It does not occupy a large space in the width direction.

Therefore, when arranging the secondary shaft 13 in which the planetary gear mechanism 50, the low mode clutch 60 and the high mode clutch 70 are arranged, the axes thereof are brought close to the axes of the input shaft 11 and the primary shaft 12. Therefore, the entire transmission 10 is reduced in size accordingly.

The control of the supply of the engagement hydraulic pressure to the low mode clutch 60 and the high mode clutch 70 by the clutch control unit 120 will be described in detail later in the description of the hydraulic control circuit.

Next, the continuously variable transmission 10 having the above configuration will be described.
Will be described.

First, when the vehicle is stopped, FIG.
2 and FIG. 2, a state in which the low mode clutch 60 is engaged and the high mode clutch 70 is released,
That is, in the low mode state, the rotation from the engine 1 is transmitted from the end of the input shaft 11 on the side opposite to the engine via the low mode gear train 80 including the first gear 81, the idle gear 83 and the second gear 82. The power is transmitted to the pinion carrier 51 of the planetary gear mechanism 50 via the low mode clutch 60.

The rotation of the engine 1 input to the input shaft 11 is transmitted from the first gear 81 of the low mode gear train 80 to the input of the first continuously variable transmission mechanism 20 via the loading cam 40 adjacent thereto. At the same time as being input to the disk 21 and transmitted to the integrated output disk 34 via the rollers 23, 23, the input disk 21 is disposed on the engine side end of the shaft 12 via the primary shaft 12. It is also input to the input disk 31 of the second continuously variable transmission mechanism 30 and transmitted to the integrated output disk 34 via the rollers 33, 33, similarly to the first continuously variable transmission mechanism 20. In that case, FIG.
By controlling the speed-increasing and deceleration hydraulic pressures P _H and P _L by the shift control unit 110 shown in FIG. The gear ratios of the mechanisms 20, 30 are controlled to the same predetermined gear ratio.

The first and second continuously variable transmission mechanisms 2
The rotation of the 0, 30 integrated output disk 34 is performed via a high-mode gear train 90 including a first gear 91 provided on the outer periphery of the disk 34 and a second gear 92 on the secondary shaft 13. The power is transmitted to the sun gear 52 of the mechanism 50.

Therefore, the planetary gear mechanism 50 includes:
The rotation is input to the pinion carrier 51 and the sun gear 52. At this time, the rotation speed ratio is set to a predetermined ratio by the speed ratio control of the first and second continuously variable transmission mechanisms 20 and 30. As a result, the planetary gear mechanism 5
The rotation of the internal gear 53 of 0, that is, the rotation input from the secondary shaft 13 to the differential device 5 via the output gear train 4 is set to zero, and the transmission 10 is in a geared neutral state.

From this state, the speed ratio of the first and second continuously variable transmission mechanisms 20 and 30 is changed to change the ratio between the input rotation speed to the pinion carrier 51 and the input rotation speed to the sun gear 52. By doing so, the internal gear 53 or the secondary shaft 13 moves in the forward or backward direction in a state where the transmission 10 as a whole (hereinafter referred to as “final transmission ratio”) is large, that is, in a low mode state. The vehicle turns and the vehicle starts.

After starting in the forward direction as described above, the low mode clutch 60 is driven at a predetermined timing.
Is released and the high mode clutch 70 is engaged, the engine 1
From the loading cam 40 in the same manner as in the low mode described above.
0, 30 input discs 21, 31 and integrated output disc 34 via rollers 23, 33 respectively.
And from the high mode gear train 90 to the secondary shaft 13 via the high mode clutch 70.

At this time, the planetary gear mechanism 50 is in the idling state, and the final speed ratio corresponds only to the speed ratios of the first and second continuously variable transmission mechanisms 20 and 30. Is controlled steplessly in a small state, that is, in a high mode state.

According to the transmission 10, the low mode gear train 80 transmitting the rotation from the input shaft 11 to the planetary gear mechanism 50 on the secondary shaft 13 side in the above-described geared neutral or low mode state.
Is arranged at the end of the input shaft 11 and the secondary shaft 13 on the side opposite to the engine.
This gear train 80 does not interfere with the differential device 5 disposed at the end of the secondary shaft 13 on the engine side or the output gear train 4 that transmits power to the device 5, so that this interference is avoided. Thus, an increase in the axial dimension of the transmission 10 due to, for example, offsetting these gear trains in the axial direction is avoided.

Incidentally, as in the continuously variable transmission 10,
First and second continuously variable transmission mechanisms 20 and 30 are provided as toroidal-type continuously variable transmission mechanisms. Input disks 21 and 31 are connected to both ends of primary shaft 12, and output disks 22 and 32 are connected to primary shaft 12. When the low-mode gear train 80 that transmits the rotation to the secondary shaft 13 is disposed at the end of the input shaft 11 on the side opposite to the engine and the input portion to the input shaft 11 and the continuously variable transmission mechanisms 20 and 30. The problem is how to place the loading cam 40 interposed therebetween.

That is, as shown in FIG. 8, the loading cam 40 'is connected to the input shaft 11' and the engine 1 '.
Input disk 31 'of the continuously variable transmission mechanism 30' located on the side
In the low mode, the torque from the engine 1 ′ is transmitted from the end of the input shaft 11 ′ on the side opposite to the engine to the secondary shaft 13 ′ via the gear train 80 ′ in the low mode, as indicated by an arrow a. While being transmitted, torque as a reaction force generated in the planetary gear mechanism 50 'on the secondary shaft 13' is transmitted to the continuously variable transmission mechanisms 20 'and 30' via the gear train 90 'as shown by an arrow b. When the circulating torque is returned to the output disk 34 'to form a circulating torque, the circulating torque is transmitted to the input disks 21', 31 'of the continuously variable transmission mechanisms 20', 30 ', and then transmitted to the engine-side continuously variable transmission mechanism 30. ′ Is input to the input shaft 11 ′ again via the loading cam 40 ′ through the input cam 31 ′, and the gear at the end opposite to the engine side via the input shaft 11 ′. It will be transmitted back to the 80 '.

Therefore, the torque (arrow a) from the engine 1 'and the circulating torque (arrow b) flow through the input shaft 11' in parallel, and the diameter of the shaft 11 'is increased. The strength must be increased. As a result, the weight of the transmission 10 increases, the rigidity of the input shaft 11 'increases, and the vibration of the engine 1' is easily transmitted to the output side, and the vibration and noise of the vehicle increase. It will be.

On the other hand, according to the continuously variable transmission 10 of this embodiment, the low-mode gear train 80 for transmitting the rotation to the secondary shaft 13 is disposed at the end of the input shaft 11 opposite to the engine. The loading cam 40 interposed between the input shaft 11 and the continuously variable transmission mechanisms 20 and 30 is also provided at the end of the input shaft 11 on the side opposite to the engine. Problems of strength and rigidity are avoided.

That is, in this case, as shown in FIG. 9, the torque from the engine 1 is transmitted from the end opposite to the engine side of the input shaft 11 to the secondary shaft 13 via the low mode gear train 80 as shown by an arrow c. Meanwhile, the circulating torque from the planetary gear mechanism 50 on the secondary shaft 13 is transmitted to the first and second continuously variable transmission mechanisms 20 via the high mode gear train 90, as shown by the arrow d.
After being returned to the output disk 34 at 30, the first continuously variable transmission mechanism 20 directly sends the low mode gear train 80 from the input disk 21 via the loading cam 40.
In the first gear 81, and on the second continuously variable transmission mechanism 30 side, from the input disk 31 to the primary shaft 12
Are transmitted from the loading cam 40 to the first gear 81 of the low mode gear train 80.

Therefore, the first and second continuously variable transmission mechanisms 2
The circulating torque returned to either 0 or 30 does not pass through the input shaft 11, and the input shaft 11 only needs to transmit torque from the engine 1. As a result, the input shaft 11
Of the transmission 10 can be reduced, the transmission 10 can be reduced in weight, the rigidity of the input shaft 11 can be reduced, and the vibration of the engine 1 can be effectively absorbed. And noise will be reduced.

Hydraulic control circuit Next, the continuously variable transmission 1 constituted by the shift control unit 110 and the clutch control unit 120 shown in FIG.
The hydraulic control circuit of 0 will be described.

As shown in FIG. 10, this hydraulic control circuit 2
00, a regulator valve 202 for adjusting the pressure of the hydraulic oil discharged from the oil pump 102 to a predetermined line pressure and outputting the adjusted line pressure to the main line 201, and a line pressure supplied from the main line 201 as a base pressure for a predetermined period. And a relief valve 204 for outputting the relief pressure to a relief pressure line 203, and a range switching operation performed by a driver of the vehicle. 205,
206, the first and third output lines 205,
207 and N range and P
Manual valve 208 that shuts off line pressure in the range
And are provided.

The regulator valve 202 and the relief valve 204 are provided with a linear solenoid valve 209 for line pressure and a linear solenoid valve 210 for relief pressure, respectively. Valve 2
The linear solenoid valves 209 and 210 each generate a control pressure based on the constant pressure generated by the reducing valve 211. The control pressures are supplied to the control ports 202a and 204a of the regulator valve 202 and the relief valve 204, so that the regulated values of the line pressure and the relief pressure are controlled by the linear solenoid valves 209 and 210, respectively. Will be.

[0091] Further, in the hydraulic control circuit 200, as transmission control, based on the line pressure and relief pressure, in each of the time of forward and during retraction, the hydraulic pressure P _H and deceleration hydraulic P _L for speed increasing Producing three-layer valve for advance 22
0 and reversing three-layer valves 230 and these three-layer valves 22
0, 230 is selectively operated.

In the shift valve 241, the position of the spool is determined by whether or not a line pressure is supplied as a control pressure to a control port 241a at one end. When the line pressure is not supplied, the spool moves to the right side. Position, the main line 201 is communicated with a line pressure supply line 242 communicating with the forward three-layer valve 220, and when line pressure is supplied, the spool is located on the left side and the main line 201 is moved backward. The line pressure supply line 243 communicating with the three-layer valve 230 is connected.

Further, the three-way valve 22 for forward and backward movement
Reference numerals 0 and 230 have the same configuration, and all have bores 221 and 231 provided in the valve body 111a of the hydraulic control unit 111 in the transmission control unit 110 shown in FIG.
(See FIG. 11), and sleeves 222, 232 fitted to be movable in the axial direction, and spools 223, 23 fitted to the sleeves 222, 232 to be also movable in the axial direction.
And 3.

The shift valve 241 is located at the center.
Line pressure ports 224, 234 connected to the line pressure supply lines 242, 243 led from the first line are connected to the first and second relief pressure ports 225, 226 to which the relief pressure line 203 is branched and connected at both ends. , 23
5 and 236, respectively, and the line pressure ports 224 and 234 and the first relief pressure port 22 are provided.
5 and 235, speed-increasing pressure ports 227 and 237
Similarly, between the line pressure ports 224, 234 and the second relief pressure ports 226, 236, a deceleration pressure port 228,
238 are provided respectively.

The operation of the three-layer valves 220 and 230 will be described with reference to the forward three-layer valve 220 as an example. As shown in FIG. 10, the sleeve 222 and the spool 223 are shifted from the neutral position to the sleeve 222 as shown in FIG. Is relatively on the drawing,
When moved to the right, the communication between the line pressure port 224 and the speed increasing pressure port 227 and the second relief pressure port 22
6 and the communication between the deceleration pressure port 228 increase,
Conversely, when the sleeve 222 moves relatively to the left, the degree of communication between the line pressure port 224 and the deceleration pressure port 228 and the degree of communication between the first relief pressure port 225 and the speed increasing pressure port 227 increase. It has become.

Further, the forward and backward three-layer valve 220,
Lines 244 and 245 respectively derived from the pressure-increasing pressure ports 227 and 237 of the 230 and deceleration pressure ports 228 and 238 of the three-way valves 220 and 230 for forward and backward movement.
Are connected to the shift valve 241.

When the spool of the shift valve 241 is located on the right side, the lines 244 and 246 led from the speed-up pressure port 227 and the deceleration pressure port 228 of the three-way forward valve 220 correspond to the speed change shown in FIG. Control unit 11
0 hydraulic chamber 11 in the trunnion drive unit 112
5 _1, 115 ₂ speed increasing pressure line 248 and the deceleration hydraulic chambers 116 ₁ leading to, 116 passed through each with the deceleration pressure line 249 leading to _2, on the contrary, when the spool of the shift valve 241 is positioned to the left, retract The lines 245 and 247 led from the speed-increasing pressure port 237 and the deceleration pressure port 238 of the three-layer valve 230 correspond to the speed-increasing hydraulic chamber 115 ₁ ,
So that the respective communicates with the speed increasing pressure line 248 and the deceleration hydraulic chambers 116 _1, 116 the deceleration pressure line 249 leading to the ₂ leading to 115 _2.

As shown in FIG. 11, the sleeves 222, 2 of the three-way valves 220, 230 for advance and retreat are provided.
Reference numeral 32 is driven in the axial direction by step motors 251 and 252, respectively. In addition, the sleeve 222 by these step motors 251 and 252,
A cam mechanism 260 for moving the spools 223 and 233 in the axial direction against the spring force of the springs 229 and 239 in accordance with the movement of the 232 is provided.

As shown in FIGS. 11 and 12, this cam mechanism 260 has a cam surface 261a having a spiral end on one end surface, and is provided with a predetermined trunnion, specifically, the second continuously variable transmission mechanism 30. precess cam 261 attached to an end of the first trunnion 35 ₁ of the rod 37 positioned above
And a shaft 262 that is disposed at one end of the spools 223 and 233 of the forward and backward three-layer valves 220 and 230 in a direction perpendicular to these, and is rotatably supported by the valve body 111a of the hydraulic control unit 111. A driven lever 263 attached to one end of the shaft 262 and having a swinging end abutting on the cam surface 261a of the precess cam 261; and a driven lever 263 similarly attached to the shaft 262 and having a swinging end Notch 2 provided at one end of spools 223, 233 of three-way reversing valves 220, 230
Drive levers 264 and 265 for forward and backward movement engaged with 23a and 233a.

[0100] Then, the first roller 33 ₁ of tilt in the second continuously variable transmission mechanism 30, the first trunnion 3
When 5 ₁ and the rod 37 is integrally rotated in the axis X direction, the precess cam 261 be integrally rotated with these, the driven lever 263 to the oscillation end on the cam surface 261a is in contact with Drive levers 264 and 265 for forward and backward movement while swinging by a predetermined amount via shaft 262.
By swinging by the same angle, the spools 223 and 233 of the forward and backward three-layer valves 220 and 230 are moved in the axial direction by an amount corresponding to the swing angle.

Accordingly, these spools 223, 2
The position of the roller 33 is the roller 33 of the second continuously variable transmission mechanism 30.
(And the roller 23 of the first continuously variable transmission mechanism 20), that is, always corresponds to the gear ratio of these continuously variable transmission mechanisms 20 and 30.

Here, according to the cam mechanism 260, as described above, the forward and backward three-layer valves 220, 230
Of the single precess cam 26
1 and the driven lever 263, the configuration of the cam mechanism is simplified as compared with the case where a precess cam or the like is provided for each of the spools 223 and 233.

As shown in FIG. 11, the step motors 251 and 252 are provided with a hydraulic control unit 1 in the shift control unit 110 in which the three-layer valves 220 and 230 are built.
11 is attached directly to the side surface of the valve body 111a with the axial center aligned with the corresponding three-layer valve 220, 230, and the two three-layer valves 220, 23 are connected by connecting members 253, 254.
Since the three-layer valve is directly connected to the sleeves 222 and 232 of the transmission case, for example, the step motor is disposed independently of the three-layer valve on a cover member of a transmission case or an oil pan, for example, and the two are connected via an interlocking mechanism. In comparison with the case, the mechanism for driving the sleeves 222 and 232 of the three-layer valves 220 and 230 by the step motors 251 and 252 is significantly simplified, and the position of the sleeves 222 and 232 can be controlled with high accuracy. It is possible to do well.

Further, in this transmission control unit 110, two three-layer valves 220, 2 for forward and backward movement are provided.
Since the shift valve 241 is disposed in the middle of the oil pump 30, the oil passage between the shift valve 241 and the three-layer valves 220 and 230, specifically, the lines 242 to 247 in the hydraulic control circuit of FIG. Therefore, the responsiveness of control using these three-layer valves 220 and 230 is improved.

On the other hand, as shown in FIG. 10, the hydraulic control circuit 200 is provided with first and second solenoid valves 271 and 272 for clutch control. 1 output line 2
05 is connected to the first solenoid valve 271, and the second output line 206 is connected to the second solenoid valve 272.

When the first solenoid valve 271 is opened, the clutch engagement pressure based on the line pressure from the first output line 205 is applied to the Felsafe valve 27.
3 and the low mode clutch line 274 is supplied to the hydraulic chamber 65 of the low mode clutch 60 to fasten the clutch 60, and when the second solenoid valve 272 is opened, the line pressure from the second output line 206 is increased. The high mode clutch line 27
5 to the hydraulic chamber 75 of the high mode clutch 70 so that the clutch 70 is engaged.

Here, the low mode clutch line 2
Accumulators 276 and 277 are provided in the high mode clutch line 74 and the high mode clutch line 275, respectively, so that the engagement pressure is gradually supplied to the low mode clutch 60 and the high mode clutch 70, so that these clutches 60 and 70 can be fastened. The occurrence of a shock at the time is suppressed.

The third output line 207 led from the manual valve 208 is connected to the control port 24 of the shift valve 241 via the fail-safe valve 273.
1a, when the manual valve 208 moves to the position of the R range, the line pressure is supplied to the control port 241a of the shift valve 241, and the spool of the shift valve 241 is moved to the left, It is designed to be moved to a position.

Also, the fail-safe valve 273
278 for fail-safe solenoid valve
The spool of the fail-safe valve 273 is located on the right side by the control pressure from the solenoid valve 278, and the first output line 205 and the low-mode clutch line 274 communicate with each other.

Here, the first and second solenoid valves 271 and 272 and the fail-safe solenoid valve 278 are all three-way valves, and when the upstream and downstream sides of the line are shut off, the downstream side is closed. Drain the side line.

Further, the first and second solenoid valves 2
Clutch control unit 12 in which 71, 272, etc. are arranged
0, as shown in FIG. 13, the upper member 121, the intermediate member 122, and the lower member 123 are connected to a plurality of bolts 124.
The first and second solenoid valves 271 and 272 are attached to the side surface of the intermediate member 122 by using the attachment plate 125 in a configuration integrated and integrated at 124.

In that case, the solenoid valves 271, 271
72, flanges 271a, 272 provided on the outer periphery
The solenoid valves 271 and 272 are fixed by sandwiching “a” between the mounting plate 125 and the side surface of the intermediate member 122. The mounting plate 125 is fixed to the upper member 121 by bolts 126 and 126. And the lower member 123, respectively, so that the upper member 121 and the lower member 123 are connected via the mounting plate 125, whereby the clutch control having a three-layer structure is achieved. The overall rigidity of the unit 120 will be improved.

In addition to the above configuration, a lubrication line 281 is provided in the hydraulic control circuit 200 shown in FIG.
The lubrication line 281 is guided from a drain port of the regulator valve 202, and is connected to the first and second transmissions 10 of the transmission 10.
A line 282 for supplying lubricating oil to each lubricating portion in the continuously variable transmission mechanisms 20 and 30; a continuously variable transmission mechanism 20 such as a planetary gear mechanism 50 and balance chambers 68 and 78 of the low mode clutch 60 and the high mode clutch 70; It branches into a line 283 for supplying lubricating oil to each part of the transmission other than 30, and a relief valve 284 for adjusting the lubricating oil pressure to a predetermined value is connected to the line 281.

The upstream of the line 282 leading to the above-described continuously variable transmission mechanisms 20 and 30 is connected to a cooling line 286 provided with a cooler 285 for cooling the lubricating oil and a bypass line 287 bypassing the cooler 285. An orifice 288 and a first on-off valve 289 are arranged in parallel on the cooling line 286 upstream of the cooler 285 in the cooling line 286.
A second opening / closing valve 29 for opening and closing the line 287 is provided at 87.
0 is set.

Here, the first and second on-off valves 28
The control of lubricating oil supply to the continuously variable transmission mechanisms 20, 30 by the control units 9, 290 will be described.

First, a control unit 30 described later is used.
0 (see FIG. 14), the second on-off valve 2
90 is opened when the temperature of the hydraulic oil is lower than a predetermined value and when the pressure of the hydraulic oil is higher than a predetermined value. At these times, the lubricating oil is supplied to the continuously variable transmission mechanisms 20 and 30 without passing through the cooler 285. Is supplied. This is because it is not necessary to cool the lubricating oil by the cooler 285 when the oil temperature is low, so that it can be efficiently supplied to the bypass line 287 having a small resistance. The reason for not performing this is to prevent the cooler 285 from being damaged by high pressure and from being deteriorated in durability.

In other cases, the second opening / closing valve 290 is closed, and the lubricating oil is cooled by the cooler 285 and then supplied to the continuously variable transmission mechanisms 20 and 30. Input and output disks 21 and
The oil film of the lubricating oil on the toroidal surfaces 2, 31, and 32 is well maintained, and the durability of the toroidal surfaces and the peripheral surfaces of the rollers 23 and 33 that come into contact with the toroidal surfaces are secured.

The first opening / closing valve 289 is also operated by a signal from the control unit 300 in a state where the second opening / closing valve 290 is closed, when the rotation speed of the engine 1 is lower than a predetermined value, and when the speed of the vehicle is reduced. It is controlled to close when it is lower than a predetermined value. This is because the required amount of lubricating oil in the continuously variable transmission mechanisms 20 and 30 is reduced at low speeds and low revolutions, while the required amount of lubricating oil is required on the clutches 60 and 70 side. At these times when the amount is originally small, the amount of lubricating oil supplied to the continuously variable transmission mechanisms 20 and 30 is suppressed, and the amount of supply to the clutches 60 and 70 is ensured.

As shown in FIG. 3, the lubricating oil supplied to the continuously variable transmission mechanisms 20 and 30 through the line 282 is supplied to the bearings of the rollers 23 and 33 by an oil passage 282a and the nozzle 282b. And are ejected to the toroidal surfaces of the output disks 21, 22, 31, 32.

Shift Control (1) Basic Operation of Control The continuously variable transmission 10 according to the present embodiment has the above-described mechanical configuration and the configuration of the hydraulic control circuit 200, and also controls the hydraulic control circuit 200. To control the speed ratio of the first and second continuously variable transmission mechanisms 20 and 30 and to control the clutch 6
The control unit 300 controls the transmission 10 as a whole by performing the engagement control of 0, 70.
Having.

As shown in FIG. 14, the control unit 300 includes a vehicle speed sensor 301 for detecting the vehicle speed of the vehicle, an engine speed sensor 302 for detecting the speed of the engine 1, and a throttle opening for the engine 1. In addition to a throttle opening sensor 303 for detecting a range of the operating oil, a range sensor 304 for detecting a range selected by a driver, an oil temperature sensor 305 for detecting a temperature of hydraulic oil, and a continuously variable transmission mechanism 20, 30 for various controls. An input speed sensor 306 and an output speed sensor 307 for detecting an input speed and an output speed, respectively, an idle switch 308 for detecting release of an accelerator pedal, a brake switch 309 for detecting depression of a brake pedal, and traveling of the vehicle. A signal from a gradient sensor 310 or the like that detects a gradient of a road surface is input. It has become way.

The linear solenoid valves 209 and 210 for line pressure control and relief pressure control and the low mode clutch 6 are controlled in accordance with the operating state of the vehicle or engine indicated by signals from these sensors and switches.
First and second solenoid valves 271 and 272 for zero and high mode clutch 70, fail-safe solenoid valve 278, first and second on-off valves 289 and 290 for lubrication control, and forward three-layer valve 220 Further, a control signal is output to the step motors 251 and 252 for the reverse three-layer valve 230 and the like.

Next, the basic operation of the shift control by the hydraulic control circuit 200 and the control unit 300 will be described. It should be noted that here, except when necessary, FIG.
Is located in the D range position,
Along with this, the spool of the shift valve 241 is
A description will be given of a case in which the vehicle is in the right forward position, and the continuously variable transmission mechanism is a first continuously variable transmission mechanism 20 shown in FIG.
It will be described as the first example roller 23 ₁ to the first trunnion 25 ₁ is positioned above.

First, the gear ratio control of the continuously variable transmission mechanisms 20 and 30 using the hydraulic control circuit 200 will be described. The signal from the control unit 300 controls the linear solenoid valve 209 for the regulator valve and the relief valve in the hydraulic control circuit 200. The linear solenoid valve 210 is operated to generate control pressures for line pressure control and relief pressure control, respectively, which are regulated by the regulator valve 202 and the relief valve 204.
Are supplied to the control ports 202a and 204a, respectively, to generate predetermined line pressure and relief pressure.

Of these oil pressures, the line pressure is transmitted from the main line 201 via the shift valve 241 and the line 242 to the line pressure port 224 of the forward three-layer valve (hereinafter simply referred to as “three-layer valve”) 220. Supplied to In addition, the relief pressure is supplied to the three-layer valve 220
Are supplied to the first and second relief pressure ports 225, 226.

Then, based on the line pressure and the relief pressure, the three-layer valve 220 is used to transfer the speed increasing hydraulic chamber 115 (115 ₁ , 115 ₂ , the same applies hereinafter) and the deceleration hydraulic chamber 116 of the transmission control unit 110, respectively. control of the differential pressure ΔP of the supplied increasing speed hydraulic P _H and deceleration hydraulic _{P L (= P H -P L} ) is performed.

This differential pressure control holds the trunnion 25 or the roller 23 at a predetermined neutral position against the traction force T acting on the trunnion 25 of the continuously variable transmission mechanism 20, and also changes the trunnion 25 and the This is performed to change the speed ratio of the continuously variable transmission mechanism 20 by moving the roller 23 along the axis X and tilting the roller 23.

Here, the traction force T will be described. As shown in FIG. 15, when the roller 23 is driven by the rotation of the input disk 21 in the direction e in the continuously variable transmission mechanism 20, as shown in FIG. These are input to the input disc 21 in the trunnion 25 supporting the
A force acts to drag in the same direction as the rotation direction e of. When the output disk 22 is driven in the g direction (x direction in FIG. 3) by the rotation of the roller 23 in the f direction, a force in a direction opposite to the rotation direction g of the output disk 22 is used as a reaction force. Acts on 23 to trunnion 25. As a result, the roller 23 and the trunnion 2
5, a traction force T acts in the illustrated direction.

Therefore, in order to hold the roller 23 at the neutral position against the traction force T, the piston 1 attached to the trunnion 25 via the rod 27
The pressure-increasing hydraulic pressure P _{H is applied to the} speed-increasing hydraulic chamber 115 and the deceleration hydraulic chamber 116 formed by the pressure-increasing hydraulic pressure P _H so that the differential pressure ΔP is equal to the traction force T.
And the deceleration hydraulic pressure P _L are respectively supplied.

Now, from this state, for example, the speed ratio of the continuously variable transmission mechanism 20 is reduced (increased speed).
11 is moved to the left side in FIG. 11 (the right side in FIG. 10), the communication between the line pressure port 224 and the speed-up pressure port 227 of the three-layer valve 220, and the second relief pressure port 226 and the deceleration pressure The degree of communication with the port 228 increases.

Therefore, the speed increasing pressure line 24 shown in FIG.
The hydraulic P _H for speed increase, which is supplied to the hydraulic chamber 115 for the speed increase from 8, together with the boosted by the line pressure of the relatively high pressure, the decelerating hydraulic chamber from the deceleration pressure line 249 11
Decelerating hydraulic P _L supplied to the 6 is depressurized by the relief pressure of the relatively low pressure, the differential pressure ΔP is increased,
As a result, the differential pressure ΔP overcomes the traction force T, and the trunnion 25 or the roller 23 moves in the h direction shown in FIG. By this movement, the roller 23 tilts in a direction in which the contact position with the input disk 21 moves outward in the radial direction and the contact position with the output disk 22 moves inward in the radial direction. The speed ratio of the speed change mechanism 20 is increased.

The tilting of the roller 23 is shown in FIG.
2 also occurs in the second continuously variable transmission mechanism 30 shown in FIG.
Due to the movement of the trunnion 35 in the i direction due to the differential pressure ΔP that overcomes the traction force T, the roller 33 moves the contact position with the input disk 31 to the outside in the radial direction and the contact position with the output disk 32 to the inside in the radial direction. The precess cam 261 of the cam mechanism 260 rotates by the same angle in the same direction (the direction j shown in FIG. 11) integrally with the tilt, thereby causing the cam mechanism 260 to tilt. Is the driven lever 263,
The shaft 262 and the drive lever 264 are both shown in FIG.
It rotates in the k direction shown in FIG.

As a result, the spool 223 of the three-layer valve 220
Moves in the l direction, that is, the left direction in FIG. 11 by the spring force of the spring 229. This direction is the direction in which the sleeve 222 is moved by the step motor 251. Therefore, as described above, Once the increased degree of communication between the line pressure port 224 and the speed increasing pressure port 227 and the degree of communication between the second relief pressure port 226 and the deceleration pressure port 228 return to the initial neutral state.

As a result, the differential pressure ΔP becomes in balance with the traction force T again, and the above-described shift operation ends, and the speed ratio of the continuously variable transmission mechanism 20 (and 30) changes by a predetermined amount. Will be fixed.

In this case, this speed change operation ends when the spool 223 moves to a position where the spool 223 reaches a predetermined neutral state in relation to the sleeve 222. 222 is moved to the position where the cam mechanism 26 is moved.
The position of the sleeve 222 corresponds to the tilt angle of the roller 23 and the trunnion 25 because the position is associated with the tilt angle of the roller 23 and the trunnion 25 through 0. As a result, the control amount of the step motor 251 corresponds to the speed ratio of the continuously variable transmission mechanism 20, and the pulse control of the step motor 251 allows the continuously variable transmission mechanism 20 (the same applies to the continuously variable transmission mechanism 30). Is controlled.

The above operation is performed by the step motor 251.
The same operation is performed when the sleeve 222 of the three-layer valve 220 is moved to the opposite side.
Gear ratio is increased (decelerated).

Here, the continuously variable transmission mechanism 2 with respect to the number of pulses of the control signal outputted to the step motors 251 and 252
The characteristics of the change in the speed ratio of 0 and 30 are as shown in FIG. 16, for example, and the speed ratio is changed (increased) so as to decrease as the number of pulses increases.

Next, the continuously variable transmission mechanisms 20 and 3 as described above
Control of the overall speed ratio (final speed ratio) of the transmission 10 using the zero speed ratio control will be described.

As described above, the speed ratio of the continuously variable transmission mechanisms 20 and 30 is controlled by the step control of the step motors 251 and 252. At this time, whether the transmission 10 is in the low mode or the high mode is determined. , That is, depending on which of the low mode clutch 60 and the high mode clutch 70 is engaged, a different final gear ratio can be obtained.

First, in the high mode, as described above, the output rotation of the continuously variable transmission mechanisms 20 and 30 is directly transmitted to the secondary shaft 13 via the high mode gear train 90 and the high mode clutch 70, and the planetary gear mechanism As shown in FIG. 17, the characteristic H with respect to the pulse number of the final transmission ratio is different from that of the continuously variable transmission mechanism 2 shown in FIG.
It becomes the same as the characteristic of the gear ratio of 0,30. However, the first gear 91 and the second gear 92 constituting the high mode gear train 90
Needless to say, the value of the gear ratio itself differs depending on the diameter or the number of teeth.

On the other hand, in the low mode, as described above, the rotation of the engine 1 is input from the input shaft 11 to the pinion carrier 51 of the planetary gear mechanism 50 via the low mode gear train 80 and the low mode clutch 60, and is continuously variable. The output rotation of the transmission mechanisms 20, 30 is transmitted to the sun gear 5 of the planetary gear mechanism 50 via the high mode gear train 90.
2 is input. In that case, the continuously variable transmission mechanisms 20, 30
By setting the ratio of the rotation speed input to the pinion carrier 51 to the rotation speed input to the sun gear 52 to a predetermined value by controlling the gear ratio of the planetary gear mechanism 50, The rotation speed of a certain internal gear 53 becomes zero, and a geared neutral state is obtained.

At this time, the final gear ratio becomes infinite as indicated by reference numerals a and b in FIG. 17, but from this state, the number of pulses of the control signals for the step motors 251 and 252 is reduced so that the final gear ratio becomes infinite. Step transmission mechanisms 20, 30
If the input rotation speed to the sun gear 52 is reduced by increasing the speed ratio of the sun gear 52 (deceleration), the internal gear 53 of the planetary gear mechanism 50 starts rotating in the forward direction, and the number of pulses decreases. , A characteristic L in which the final speed ratio becomes smaller is obtained, and a low mode in the D range is realized.

The low mode characteristic L and the high mode characteristic H of the D range are, as shown by reference numeral c in the figure, a predetermined number of pulses (around 500 pulses in the example), that is, the continuously variable transmission mechanism 20. , 30 at predetermined gear ratios (around 1.8 in the example in the figure). Therefore, at this intersection c, the low mode clutch 6
If the 0 and the high mode clutch 70 are switched, the mode can be switched while the final gear ratio is continuously changed.

By increasing the number of control signal pulses for the step motors 251 and 252 from the geared neutral state, the continuously variable transmission mechanism 20
By changing the speed ratio of 30 to a smaller direction (increased speed),
If the input rotation speed to the sun gear 52 is increased, the internal gear 51 of the planetary gear mechanism 50 starts to rotate in the reverse direction, and the characteristic R of the R range in which the final speed ratio increases as the number of pulses increases is obtained. .

Based on the above control characteristics,
The control unit 300 controls the final gear ratio according to the driving state of the vehicle as follows.

That is, the control unit 300
Are the vehicle speed sensor 301 and the throttle opening sensor 30
3, the vehicle speed V and the throttle opening .theta. At the present time are read out, and from these values and a map set in advance as shown in FIG.
Set o. And this target engine speed Neo
(The value corresponding to the angle α in FIG. 18)
In order to obtain the low mode clutch 60 and the high mode by the pulse control for the step motors 251 and 252 and the control for the first and second solenoid valves shown in FIG. 10 based on the control characteristics of FIG. The engagement control of the clutch 70 is performed.

On the other hand, the step motor 25 as described above
Continuously variable transmission mechanisms 20, 30 by pulse control of 1,252
In addition to the gear ratio control (hereinafter referred to as "three-layer valve control"),
The control unit 300 in the transmission 10
Is configured to directly generate a predetermined differential pressure ΔP by controlling the relief pressure by a linear solenoid valve 210 to control the speed ratio of the continuously variable transmission mechanisms 20 and 30 (hereinafter, this control is referred to as “direct control”). Control)). The reason is as follows.

The three-layer valve control includes a step motor 251,
It is premised that there is a certain correlation between the number of pulses 252, that is, the amount of movement of the sleeves 222 and 232 and the differential pressure ΔP generated therewith.
For example, as shown in FIG. 19, when the sleeve is moved in the direction in which the differential pressure ΔP is increased, and when the sleeve is moved in the direction in which the differential pressure is decreased, as shown in FIG. Hysteresis may occur between them. Due to such hysteresis, for example, at a point near the geared neutral (GN) as indicated by a reference sign D, the differential pressure ΔP is inverted across the geared neutral position. Drive rotation occurs.

To cope with such a problem, the differential pressure ΔP may be directly generated and supplied to the speed-increasing hydraulic chamber 115 and the deceleration hydraulic chamber 116. For this purpose, it is necessary to control the line pressure. However, since the line pressure is generally as large as the control width of about 4 to 16 kg, a fine differential pressure ΔP
In addition, the line pressure must be increased in order to generate the predetermined differential pressure ΔP, and the oil pressure in the entire circuit increases, resulting in an increase in oil pump loss.

Therefore, if the same differential pressure ΔP is generated, it is more advantageous to reduce the relief pressure, which is a hydraulic pressure equal to or less than the line pressure, and the control range of the relief pressure is generally about 0 to 4 kg. Therefore, it can be suitably used for precise control of the differential pressure ΔP.

In this direct control, the speed increasing hydraulic chamber 1
As 15 and the hydraulic P _H for speed increase is supplied to the speed reduction hydraulic chamber 116 and the speed reduction hydraulic P _L, is directly supplied without the line pressure and the relief pressure is pressure regulated three layers valve 220. Now, assuming that the sleeve 222 and the spool 223 of the three-layer valve 220 are in the neutral state shown in FIG. 10 and the speed ratio of the continuously variable transmission mechanism 20 is to be reduced (increased) from this state, first, the sleeve 222 Is moved to the right side in the drawing by a predetermined amount to increase the communication between the line pressure port 224 and the speed increasing pressure port 227 and the communication between the second relief pressure port 226 and the deceleration pressure port 228, thereby increasing the line pressure. The pressure is supplied from the high speed line 248 to the speed increasing hydraulic chamber 115, and the relief pressure is reduced by the deceleration line 249.
From the hydraulic chamber 116 for deceleration.

[0152] As a result, the roller 23 moves the trunnion 25 or the roller 23 is in the accelerating direction by the pressure difference ΔP between the relief pressure of the deceleration hydraulic P _L to the line pressure as these increasing speed hydraulic P _H The roller 23
The spool 223 moves in the moving direction of the sleeve 222 by the cam mechanism 260 according to the tilt angle of
In this case, the inclination angle of the roller 23 or the spool 223
Is determined by the differential pressure ΔP, and is not determined by the initial movement of the sleeve 222. Therefore, the movement of the sleeve 222 is If the communication relationship between the ports is maintained even if the spool 223 moves, or if the sleeve 222 is moved in such a manner, the sleeve 222 is further moved in a predetermined direction, and If the communication relationship between the ports is maintained, even after the roller 23 is tilted and the spool 223 is moved, the direct shift control by the differential pressure ΔP is always possible.

In this transmission 10, the direct control is performed especially near geared neutral, which is liable to be affected by hysteresis in the three-layer valve control, that is, at a low vehicle speed. Further, the control unit 300 of the transmission 10 generates creep force as in an automatic transmission having a torque converter when the direct control is performed at a low vehicle speed and the idle switch 308 is on. Control (hereinafter, referred to as "creep control") that does not intentionally realize the geared neutral state is performed. The reason is as follows.

That is, the geared neutral is input to the sun gear 52 of the planetary gear mechanism 50 via the high mode gear train 90 and to the pinion carrier 51 of the planetary gear mechanism 50 via the low mode gear train 80. The internal gear 53 of the planetary gear mechanism 50 is prevented from rotating by setting the ratio with respect to the rotation speed to be set to a predetermined value. Therefore, the toroidal speed ratio in the low mode is controlled by the three-layer valve control. The gears and the sun gear 52 and the pinion carrier 5 for realizing such geared neutral are controlled by direct control.
The value of the rotational speed ratio with 1 is one, and therefore, the value of the toroidal speed ratio is also unique. As a result, very precise control of the toroidal gear ratio is required, and sometimes the vehicle is shifted in the forward direction or the backward direction.

Considering the case of starting after a temporary stop, in geared neutral, the vehicle does not start just by releasing the brake pedal, but must step on the accelerator. Therefore, in order to ensure good starting performance by always applying a certain amount of driving force to the vehicle as in an automatic transmission having a torque converter, for example, in a forward traveling range such as a D range, the driving force in the forward direction is slightly increased. The toroidal speed ratio is controlled by shifting the gear neutral from the geared neutral so that the vehicle operates in the reverse range and the driving force in the reverse direction slightly acts in the reverse range. In such creep control, precise control is not so required, which is advantageous in terms of control operation.

As described above, in the transmission 10, the creep control is executed at a low vehicle speed at which the direct control is performed and when the idle switch 308 is turned on. If the vehicle speed decreases with the foot released, the vehicle switches from three-layer valve control to direct control and enters creep control at the same time.On the other hand, the vehicle speed decreases when the accelerator pedal is depressed on an uphill road or the like. In such a case, after the normal shift control based on the shift map is performed by direct control, the creep control is started when the accelerator pedal is released to depress the brake pedal or the like.

When the vehicle is stopped, the creep force is reduced as much as possible to save fuel economy. At the time of starting, the creep control is started from the beginning, and the operation shifts to the normal direct control by depressing the accelerator pedal. ,
When the vehicle speed becomes equal to or higher than the predetermined vehicle speed, the control is switched to the three-layer valve control.

(2) Specific Operations of Each Control As shown in FIG. 20, the control unit 300 stores various control programs for coping with various situations based on the above-described shift operation. Each control is executed independently or in association with another control and executed when necessary.

(2-1) Line Pressure Control As described above, the pressure of the hydraulic oil discharged from the oil pump 102 is adjusted to a predetermined line pressure by the linear solenoid valve 209 via the regulator valve 202 and the main line is controlled. The line pressure is supplied to the relief pressure line 203 through the relief valve 204, and the line pressure is adjusted to a pressure lower than the line pressure by the linear solenoid valve 210 and supplied to the relief pressure line 203. The trunnions 25, 35 are guided in the predetermined direction while being guided to the three-layer valves 220, 230 and maintaining the rollers 23, 33 or the trunnions 25, 35 of the continuously variable transmission mechanisms 20, 30 at the neutral position against the traction force T. It is important to generate a differential pressure ΔP for shift control in which the rollers 23 and 33 are tilted by moving. It is used as a force.

Therefore, the differential pressure ΔP for holding the trunnions 25 and 35 at the neutral position is controlled in accordance with the increase or decrease of the traction force T. For example, if the relief pressure is fixed, the line By increasing the pressure, the differential pressure ΔP can be increased to oppose a larger traction force T. Conversely, when the line pressure is constant, the differential pressure ΔP can be increased by decreasing the relief pressure. As a result, it is possible to face a larger traction force T.

In this case, the traction force T does not simply change depending on the magnitude of the engine torque or the like, but also changes depending on the tilt angles of the rollers 23 and 33. That is, the first continuously variable transmission mechanism 20 shown in FIG.
Tilting the first roller 23 _1, as shown in the example, if the roller 23 ₁ as a result of the shift control is tilted to the deceleration side as shown by a solid line in the diagram, the acceleration side as shown by a chain line as compared with the case where rolling was, since the radius r1 of the contact position between the roller 23 ₁ and the input disc 21 decreases, the rollers at this time torque Tz from the input disk 21 side 2
3 assuming that are transferred to _1, even the size of the torque Tz are the same, the roller 2 at the contact position
Force to Hikizuro 3 ₁ becomes larger, and also increases the reaction force at the contact position between the roller 23 ₁ and the output disk 22. Therefore roller 23 ₁ traction force T as a whole increases as tilts on the deceleration side.

The direction in which the torque Tz is transmitted is as described above when the low mode clutch 60 is released and the high mode clutch 70 is engaged in the high mode (H mode). Sometimes, the relief pressure is kept constant so that the differential pressure ΔP facing the traction force T increases as the speed ratio of the continuously variable transmission mechanism 20.30 (hereinafter also referred to as “toroidal speed ratio”) increases. Performs control to increase the line pressure and decrease the relief pressure when the line pressure is kept constant.

On the other hand, in the low mode (L mode), the continuously variable transmission mechanism 2 receives the reaction force from the planetary gear mechanism 50 described above.
The direction of torque transmission is opposite to that in the high mode due to the circulating torque recirculated to the 0.30 side (see FIG. 9). Therefore, the low mode, when the roller 23 ₁ is tilted to the acceleration side as shown by the chain line in FIG. 21, the roller 2
3 from ₁ and the traction force T radius r2 is smaller in the contact position between the output disk 22 is increased, as the toroidal speed ratio becomes smaller, so the differential pressure ΔP facing the traction force T is enlarged, the relief pressure Is constant, the line pressure is increased, and when the line pressure is constant, the relief pressure is reduced.

The specific operation of the line pressure control performed by the control unit 300 is as shown in FIG. 22, for example. In step S11, the engine speed Ne and the throttle opening θ
Then, the toroidal speed ratio Rtd is calculated from the engine torque Te, the oil pump loss Loss in step S12, and the input speed and output speed of the continuously variable transmission mechanisms 20 and 30 in step S13.
Then, using these calculated values and modes as parameters,
For example, the value of the transmission torque Tz is obtained from a map as shown in FIG. As shown, in this map, in the low mode D range, the transmission torque Tz increases as the toroidal speed ratio Rtd increases, and in the high mode, the transmission torque Tz is fixed at 1.0.

Next, in step S15, a value of the line pressure PL is obtained from a map such as that shown in FIG. 24 based on the transmission torque Tz, and in step S16, the linear solenoid valve 20 is set so that the line pressure PL is obtained.
9 is controlled. In the above-mentioned map, the line pressure PL increases when the transmission torque Tz is equal to or more than a predetermined value so that the transmission pressure Tz can be opposed to the traction force T. , The line pressure PL is set to be larger as the state becomes, and in the high mode, the line pressure PL is set to be larger as the toroidal speed ratio Rtd is on the deceleration side.

When the transmission torque Tz is less than a predetermined value, the line pressure PL is fixed at a constant value, but within this range, the relief pressure is increased or decreased to control the differential pressure ΔP. That is, in the low mode, the relief pressure is further reduced as the toroidal speed ratio Rtd increases, and in the high mode, the relief pressure is further reduced as the toroidal speed ratio Rtd decreases.

(2-2) Engage Control As described above, in the N range, the main line 201 for supplying the line pressure and the first to third output lines 205 to 207
Is shut off by the manual valve 208,
Both the low mode clutch 60 and the high mode clutch 70 are in a released state. From this state, when the driver switches the range to the forward travel range such as the D range, the S range, or the L range, or the reverse travel range of the R range, first, the low mode clutch 60 is set to achieve the low mode. Is concluded. At this time, if the toroidal speed ratio is controlled to a speed ratio that realizes geared neutral, the rotation is synchronized between the pinion carrier 51 of the planetary gear mechanism 50 and the second gear 82 of the low mode gear train 80. Therefore, even if the low mode clutch 60 that connects or disconnects these clutches is engaged, almost no shock occurs due to the engagement.

However, since the N range is usually selected when the vehicle is stopped in an idle state or at a low vehicle speed, the engagement operation of ND or NR is performed during the aforementioned creep control. become. Therefore,
Since the geared neutral state is not established during the creep control, a shock due to the creep torque occurs when the low mode clutch 60 is engaged.

Therefore, the control unit 300
In order to suppress such an engagement shock, the engagement control according to the flowchart shown in FIG. 25 is performed. Next, this engagement control will be described with reference to the relationship diagram between the number of pulses of the step motor 251 and the final gear ratio shown in FIG. 26, the relationship diagram between the relief pressure and the output torque shown in FIG. 27, and the time chart shown in FIG. I will explain it.

That is, the control unit 300
First, in step S21, it is determined whether or not the range is the N range in the previous control cycle, and if YES, it is determined in step S22 whether or not the current range is the travel range such as D, S, L, R, etc. judge. If NO, that is, if the N range is continued, the relief pressure Prf is set to 0 in step S23, and the pulse PULS of the step motor 251 is set to PN for realizing geared neutral in step S24. In S25, the timer value TIM is set to 0.

Here, during the continuation of the N range, the relief pressure Prf
Is set to 0 because the relief pressure Prf becomes 0 when the relief pressure control linear solenoid valve 210 is not operated, which is advantageous because excess power is not consumed. Also,
PN that realizes pulse PULS by geared neutral
The reason is that the sleeve 222 is returned to the reference position in preparation for generating the creep force in the next engagement operation by the direct control, and is not necessarily limited to this position. Any position may be used as long as the positional relationship between the sleeve 222 and the spool 223 in the valve 222 is in a predetermined neutral state and communication between the ports is interrupted.

On the other hand, if the current range is D,
When the travel range is set to S, L, R, or the like, while the timer value TIM is equal to the predetermined time TIMx required for engaging the low mode clutch 60 in step S26, the relief pressure Prf is increased to a relatively high predetermined oil pressure Prf (on) in step S27. In addition, step S is performed so that the communication between the ports in the three-layer valve 222 is maintained and the direct control can be performed.
If the pulse PULS of the step motor 251 is switched to the forward travel range such as the D range at 28, the PN
If the final speed ratio is switched to the high speed side reversing travel range from the final speed ratio to the high speed side PD1, the final speed ratio is similarly set to the high speed side PR1 and then the timer value TIM is increased by one in step S29.

That is, during the predetermined time TIMx required for engaging the low mode clutch 60, the relief pressure Prf is increased, and as a result, the pressure difference ΔP from the line pressure is reduced to approach geared neutral, and the creep force (output torque) Is set lower. Therefore, the engagement shock in the engagement operation is suppressed.

Then, in step S26, the timer value TI
M is a predetermined time T required for engaging the low mode clutch 60
If it exceeds IMx, at step S31 the relief pressure P
rf is set to a relatively low predetermined oil pressure Prf (off), and the direct control can be executed so that the communication state between the ports of the three-layer valve 222 is maintained and the direct control can be executed.
In step 2, the pulse PULS of the step motor 251 is switched from the above-mentioned PN to PD0 on the low-speed side when the pulse PULS is switched to the forward traveling range such as the D range. After the final gear ratio is set to PR0 on the low speed side, the timer value TIM is set to 0 in step S33.

That is, after the low mode clutch 60 is engaged, the relief pressure Prf is lowered, and as a result, the differential pressure ΔP from the line pressure is increased, the deviation from geared neutral is increased, and the creep force (output) torque)
Will be set higher. Therefore, good startability is ensured.

(2-3) Direct Control Although the basic operation of the direct control itself is as described above, the control unit 300 of the transmission 10 is particularly operated when the brake pedal is depressed or during creep. Special control is performed on the vehicle speed. A specific control operation in that case is as shown in a flowchart of FIG. 28. This will be described with reference to a time chart of FIG. 31. First, in step S41, the vehicle speed V is increased by a predetermined amount ΔV from the target vehicle speed Vo in creep control. When the vehicle speed falls below a large vehicle speed, the control shifts from the three-layer valve control to the direct control. In this case, if the brake switch 309 is on in step S42 (the idle switch 308 is on at this time and the creep control is started) ), The relief pressure Pr in step S43
f is set to a relatively high predetermined oil pressure Prf (on), and step S4 is performed so that the relief pressure Prf (on) is obtained.
In step 4, the linear solenoid valve 210 is controlled. That is, when the brake pedal is depressed, it is preferable to decelerate early, so that the relief pressure Prf is increased and the creep force is reduced.

On the other hand, when the brake switch 309 is off in step S42, the relief pressure P is determined in step S45.
rf is set to a relatively low predetermined oil pressure Prf (off). When the idle switch 308 is turned on in step S46, a deviation dV between the current vehicle speed V and the target vehicle speed Vo in the creep control is obtained in step S47. Then, in step S48, the deviation dV is obtained from the map shown in FIG. Feedback pressure ΔPr of the relief pressure based on
Find f. Then, in step S49, a relief pressure Prf obtained by adding the feedback oil pressure ΔPrf is obtained.
Step S44 so that this relief pressure Prf is obtained.
Controls the linear solenoid valve 210. As a result, when the brake pedal is not depressed, the vehicle speed is maintained at the target vehicle speed Vo by feedback control without reducing the creep force.

Note that the time chart of FIG. 31 shows feedback control of the vehicle speed to the target vehicle speed Vo from the stop of the vehicle to the start of the vehicle. In step S41, the start condition of the direct control is set to the target vehicle speed V.
The reason why the vehicle speed is set to be larger by a predetermined amount ΔV than o is to prevent overshooting during feedback control of the vehicle speed V and switching to the three-layer valve control.

When the idle switch 308 is turned off in step S46, that is, when the accelerator pedal is depressed, the relief pressure Prf is determined in step S50 according to the throttle opening θ, and the relief pressure Prf is obtained. Next, in step S44, the linear solenoid valve 210 is controlled (the period of Δt when the vehicle starts in FIG. 31). In this case, as shown in FIG. 30, the relationship between the relief pressure Prf and the throttle opening θ is set in a map such that the relief pressure Prf increases as the throttle opening θ increases. As a result, the creeping force decreases as the amount of depression of the accelerator increases, in other words, approaches the geared neutral state, and as a result,
The gear ratio is increased, the engine speed is increased, good acceleration is obtained, and switching to three-layer valve control is performed smoothly.

When the vehicle speed V becomes equal to or higher than the vehicle speed which is the start condition of the direct control in step S41, the process proceeds to step S51, where the differential pressure ΔP during the three-layer valve control is generated between the vehicle and the line pressure. The relief pressure Prf is set to 0, and the linear solenoid valve 210 is controlled in step S52 so as to obtain the relief pressure Prf.
At 53, the control shifts to three-layer valve control.

Note that the number of pulses of the step motor 251 at the time of switching between the three-layer valve control and the direct control is not always the same, and when the direct control is started, the position of the sleeve 222 at the end of the three-layer valve control is changed. Moving the position (pulse number PD0) of the sleeve 222 at the end of the direct control (pulse number PD0) to the position corresponding to the three-layer valve control when the three-layer valve control is started. become.

In the direct control, when the brake switch 309 is turned on in step S42,
Control is performed to increase the relief pressure Prf to reduce the creep force. For example, when the vehicle stops on a slope such as an uphill road instead of a flat road, the creep is immediately turned on when the brake switch 309 is turned on. When the force is reduced, there is a concern that the forward driving force is reduced and the vehicle runs backward. Therefore, the control unit 30 in the transmission 10
0 stores a second direct control program for dealing with such a problem.

Next, the second direct control including the gradient control will be described with reference to the flowchart shown in FIG. 32 and the time chart shown in FIG. The flowchart in FIG. 32 is the same as the flowchart in FIG. 28 except that step S40 is added before step S41 and step S43 is changed.

First, before judging the start or end condition of the direct control in step S41, the delay time Tcd and the relief pressure Prf are determined in step S40 according to the road surface gradient k detected by the gradient sensor 310. In this case, as shown in FIG. 33, the steeper the ascending gradient, the longer the delay time Tcd and the smaller the relief pressure Prf (the larger the creep force). In addition, the relief pressure Prf0 when the vehicle is on a flat road is a value that generates a normal creep force.

Then, the direct control is started in step S41, and the brake switch 309 is set in step S42.
Is ON, the process first proceeds to step S43a,
It is determined whether or not the count number count is 0, and in the case of YES, that is, when the process proceeds to step S43a for the first time, in step S43b, as in the case where the brake switch 309 is off, the relief pressure Prf (provided that the gradient Determined) is changed to a relatively low predetermined oil pressure Prf (of
f), the count is incremented by 1 in step S43c, and in step S43d, the count is
A comparison is made with the delay time Tcd determined according to the gradient.

If it is still within the delay time Tcd, in step S43e, the relatively low predetermined oil pressure P
If rf (off) is maintained while the delay time Tcd is exceeded, in step S43f, a calculation is performed to increase the relief pressure Prf according to the count number. The correction coefficient Ck used for the calculation is set so that the steeper the slope is, as shown in FIG. 34, the smaller it is, that is, the relief pressure Prf is slowly increased (the creep force is slowly decreased). Then, the linear solenoid valve 210 is controlled in step S44 so as to obtain the relief pressure Prf determined as described above.

According to this control, the steeper the vehicle climbs on the road surface, the greater the creep force after depressing the brake pedal, and the longer the delay time, which is the holding time, Even when the creep force is reduced after the delay time has elapsed, the vehicle is slower as the ascending gradient is steeper, so that the vehicle is effectively prevented from returning on a sloping road surface. .

(2-4) DR Return Control For example, in the case of garage parking, the range is switched to the R range in an attempt to reverse while the vehicle is still moving forward (DR), and vice versa. (RD) may be performed. Considering the state at this time with the gear train of the transmission 10, the manual valve 2
08 passes through the N-range position while moving between the D-range position and the R-range position, but for a very short time, the low-mode clutch 60 remains engaged.

In this state, the toroidal speed ratio changes across the geared neutral. At this time, the toroidal speed ratio is changed so that the internal gear 53 or the secondary shaft 13 is rotated in the direction opposite to the current rotation direction. By controlling, the rotation speed of the sun gear 52 is changed. Therefore, the rollers 23 and 33 of the continuously variable transmission mechanisms 20 and 30 are discs 21, 22, and
A large force is required to incline the rollers 31 and 32, and as a result, the rollers 23 and 33 and the discs 21 and 32 are required.
There is a possibility that slips may occur on 2, 31, 32 and cause damage.

Therefore, the control unit 300
At the time of switching back and forth between forward and backward, the following control is performed according to the flowchart shown in FIG. 36 so as not to apply a large load to the continuously variable transmission mechanisms 20 and 30.

First, when the D range is set in step S61, normal three-layer valve control by sleeve movement based on a shift diagram (shift map) as shown in FIG. 18, for example, is performed in step S62, while step S61 is performed. If the range is not the D range and the range is the N range in step S63, the low mode clutch 60 is released in step S64, and the
After moving the sleeve 222 of the three-layer valve 220 to a position near the geared neutral at 65, step S66
, The origin of the step motor 251 is corrected. It should be noted that the reason for moving the sleeve 222 to a position near the geared neutral rather than the geared neutral position in the above step S65 is due to the aforementioned reason that it is difficult to accurately move the sleeve 222 to the geared neutral position. It goes without saying that the sleeve 222 may be moved to the geared neutral position (the position at which the sleeve 222 is moved in this step S65 is referred to as a “reference position”).

As a result, in the N range, the power transmission path is cut off, the sleeve 222 is moved to the reference position, and the origin of the step motor 251 is corrected here. The origin correction of the step motor 251 is performed roughly as follows. First, the input rotation sensor 306 is provided on the low mode clutch drum 61, and the output rotation sensor 307 is provided on the second gear 92 of the high mode gear train 90. The toroidal speed ratio at the reference position is calculated. Also, the sleeve 222
The number of pulses when is moved to the reference position is defined as the number of origin pulses (for example, about 1360 in FIG. 17). Then, the calculated actual speed ratio of the toroid is compared with the ideal speed ratio of the toroid at a preset reference position, and the sleeve 222 is moved in a direction in which the difference is eliminated. The movement of the sleeve 222 is feedforward control, and the number of pulses of the step motor 251 after moving the sleeve 222 by the number of pulses is replaced with the number of pulses of the origin.

Returning to FIG. 36, if it is not the D range in step S61 and if it is not the N range in step S63, it is determined in step S67 whether or not the R range. If NO, the S range or the L range is used. If yes, the process proceeds to step S62, while if YES, it is determined in step S68 whether the vehicle is traveling backward. When the vehicle is traveling backward, normal three-layer valve control is performed in step S62. On the other hand, in the case of NO, it is determined whether or not the vehicle speed is not 0 in step S69. When the vehicle is traveling forward, steps S64 to S66 performed in the above-mentioned N range are executed.

On the other hand, if NO in step S69, that is, if the vehicle is stopped in the R range, the process proceeds to step S70 to move the sleeve 222 of the three-layer valve 220 to the reverse start position. Specifically, the internal gear 53 or the secondary shaft 1
3 is moved to the position at the time of creep start, which is the reverse rotation. Then, the low mode clutch 60 is engaged in step S71.

According to this control, when switching back to the R range is performed during forward running, step S61,
Proceed to S63, S67, S68, S69, and step S
After the low mode clutch 60 is disengaged at 64, the stop of the vehicle is confirmed at step S69, and then the sleeve is moved in the retreating direction at step S70.
Since the low mode clutch 60 is connected at 71, the sun gear 52 of the planetary gear mechanism 50 rotates with a small load while the low mode clutch 60 is disengaged.
Since the roller 23 of the continuously variable transmission 20 is tilted so as to change the rotation speed of the sun gear 52, the tilt can be performed with a small load, and as a result, the rollers 23 and 33 and the disk 21 can be rotated. , 22, 31, and 32, and there is no possibility of causing damage.

(2-5) RD Switchback Control Although the flowchart shown in FIG. 36 relates to the DR switchback control, the reverse RD switchback control is performed in accordance with this. FIG. 37 shows the control flow.

(2-6) Reverse Shift Control In the continuously variable transmission 10, the toroidal speed ratio can be controlled in a stepless manner. As a result, by changing the rotation speed of the sun gear 52, the vehicle can move forward from geared neutral. It is possible to arbitrarily change the final gear ratio in both the direction and the reverse direction. Therefore, it is possible to set an infinite number of gears even when the vehicle is traveling backwards, but particularly when the vehicle is traveling backwards, unlike the forward traveling that requires good start acceleration, special attention is required when starting the vehicle. .

Therefore, as shown in FIG. 38, when the range is the R range in step S101, the control unit 300 in the continuously variable transmission 10 proceeds to step S1.
At step S02, the shift control is performed using the reverse speed shift map, and when the range is the D range, at step S103, the shift control is performed using the forward speed shift map.

In this case, as shown in FIG. 39, the shift map for the reverse speed has a lower value than the shift map for the forward speed even at the same vehicle speed V and the same throttle opening θ. The engine speed is determined as the target value Neo. In other words, the final gear ratio is shifted to the higher gear side as a whole, thereby suppressing a sudden jump when the vehicle retreats.

It should be noted that the characteristics of such a reverse speed shift map may be applied only when the vehicle speed is equal to or lower than a predetermined vehicle speed. In such a case, the running at the same final gear ratio as in the case of the forward running is realized except at the time of starting where special attention is required.

In FIG. 39, the shift characteristics are not set below the determined vehicle speed Vo + .DELTA.V in the direct control described above, but this is added according to the time chart of FIG. At the time of switching from the control to the direct control, the idle switch 308 has already been turned on, and thus the creep control is immediately started.
The following shows that normal shift control is not performed, and that this kind of shift map is not used.

(2-7) Low Mode / High Mode Switching Control As described above with reference to FIG. 17, the low mode characteristic and the high mode characteristic of the D range intersect at a predetermined pulse number or toroidal speed ratio. Characteristics. This is represented as a mode switching line in the shift map of FIG. 18 or FIG. That is, the low mode clutch 60
And the high mode clutch 70 is changed. As a result, it is possible to realize a mode switching without a shock without causing a sudden change in the gear ratio.

However, since it takes some time to change the clutches 60 and 70, when the mode switching is completed, the running state of the vehicle is not already on the mode switching line. A change in the ratio will occur.

Therefore, the control unit 300
In order to deal with such a problem, the mode switching control according to the flowchart shown in FIG. 40 is performed. First, in step S111, the control unit 300 multiplies the actual engine speed Ne detected by the engine speed sensor 302 by the final speed ratio Go of the mode switching line and the vehicle speed V detected by the vehicle speed sensor 302. It is determined whether or not the obtained value is approaching. That is, it is determined whether the current final gear ratio is substantially the same as the mode switching line.

Then, in the case of YES, step S11
At 2, the toroidal speed ratio is controlled so that the current final speed ratio G is maintained while the clutches 60 and 70 are being changed. Next, at step S113, the final gear ratio G is set.
The difference ΔN between the target engine speed Neo and the actual speed Ne for maintaining the engine speed Ne is calculated, and in step S114, the feedback of the pulse PULS from the map shown in FIG. 41 set so as to eliminate the rotation error ΔN Quantity ΔPU
LS is obtained, and finally, the feedback amount ΔPULS is output to the step motor 251 in step S115.

As a result, the sleeve 22 of the three-layer valve 220
The two positions are feedback-controlled, and the rotational deviation ΔN
Is resolved, and as a result, the final gear ratio G is fixed at a constant value. Since the mode is switched during that time, there is no change in the gear ratio before and after the mode switching, and a smooth mode switching without shock is realized.

[0207]

As described above, according to the first aspect of the present invention, during switching between the first and second transmission paths, the same transmission ratio is maintained between the transmission paths. Since the toroidal transmission mechanism is controlled, even if it takes time to switch between the low mode and the high mode and the vehicle speed and the throttle opening change during that time, the rotation may be out of synchronization at the end of the switching of the mode. Thus, the occurrence of a shock due to a sudden change in the gear ratio is avoided.

Further, according to the second aspect of the invention, a configuration for maintaining the same speed ratio is realized, and the trunnion moves with respect to the input / output disk by moving the sleeve of the three-layer valve, so that the roller tilts. When the transmission path is switched, the sleeve is fixed so as not to move the trunnion during the switching of the transmission path, so that the inclination angle of the roller does not change, and the first and the second The same gear ratio is maintained between the two control modes.

[Brief description of the drawings]

FIG. 1 is a skeleton diagram showing a mechanical configuration of a toroidal-type continuously variable transmission according to an embodiment of the present invention.

FIG. 2 is a development view showing a specific structure of a main part of the transmission.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a cross-sectional view showing a mode of assembling the gears constituting the high mode gear train.

FIG. 5 is a partially cutaway view showing an assembling relationship between a loading cam, gears forming a low mode gear train, and an input disk.

FIG. 6 is an enlarged sectional view showing a configuration on an input shaft.

FIG. 7 is an enlarged sectional view showing a configuration on a secondary shaft.

FIG. 8 is a schematic diagram illustrating a problem due to a circulation torque.

FIG. 9 is a schematic diagram illustrating a flow of a circulating torque in the transmission according to the embodiment of the present invention.

FIG. 10 is a circuit diagram of hydraulic control of the transmission.

FIG. 11 is a partial cross-sectional view of a three-layer valve that generates a hydraulic pressure for speed change control as viewed from a direction B in FIG. 3;

FIG. 12 is a partial cross-sectional view of the cam mechanism as viewed from a direction C in FIG. 3;

FIG. 13 is a sectional view showing a lower structure of the transmission case.

FIG. 14 is a control system diagram in the transmission according to the embodiment of the present invention.

FIG. 15 is an explanatory diagram of traction force that is a premise of gear shift control.

FIG. 16 is a characteristic diagram showing a relationship between the number of pulses of a step motor and a toroidal speed ratio.

FIG. 17 is a characteristic diagram showing a relationship between the number of pulses of a step motor and a final gear ratio.

FIG. 18 is a characteristic diagram used for speed change control.

FIG. 19 is an explanatory diagram of a problem in speed change control by a three-layer valve.

FIG. 20 is a main flowchart of the control performed by the control unit.

FIG. 21 is an explanatory diagram of features of line pressure control performed by the control unit.

FIG. 22 is a flowchart of the line pressure control.

FIG. 23 is a characteristic diagram in the line pressure control.

FIG. 24 is a characteristic diagram in the line pressure control.

FIG. 25 is a flowchart of the engagement control performed by the control unit.

FIG. 26 is a characteristic diagram in the engagement control.

FIG. 27 is a characteristic diagram in the same engagement control.

FIG. 28 is a flowchart of direct control performed by the control unit.

FIG. 29 is a characteristic diagram in the direct control.

FIG. 30 is a characteristic diagram in the direct control.

FIG. 31 is a time chart diagram of the direct control and the engagement control.

FIG. 32 is a flowchart of a second direct control including a gradient control.

FIG. 33 is a characteristic diagram in the second direct control.

FIG. 34 is a characteristic diagram in the second direct control.

FIG. 35 is a time chart according to the second direct control.

FIG. 36 is a flowchart of the switching control performed by the control unit.

FIG. 37 is a flowchart of another return control.

FIG. 38 is a flowchart of a reverse shift control performed by the control unit.

FIG. 39 is a shift characteristic diagram in the reverse shift control.

FIG. 40 is a flowchart of mode switching control performed by the control unit.

FIG. 41 is a characteristic diagram in the mode switching control.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Engine 10 Toroidal continuously variable transmission 11 Input shaft 12 Primary shaft 13 Secondary shaft 20, 30 Continuously variable transmission mechanism 21, 31 Input disk 22, 32 Output disk 23, 33 Roller 25 Trunnion 50 Planetary gear mechanism 51 Pinion carrier 52 Sun gear 53 Internal gear 60 Low mode clutch 70 High mode clutch 80 Low mode gear train 90 High mode gear train 100 Transmission case 110 Transmission control unit 111 Hydraulic control unit 112 Trunnion drive unit 115 Hydraulic chamber for speed increase 116 Hydraulic chamber for deceleration 120 Clutch control Unit 220, 230 Three-layer valve 241 Shift valve 271, 272 Solenoid valve

Claims (2)

[Claims] 1. A toroidal speed change mechanism for changing a speed ratio between two disks by tilting a roller disposed in a pressure-contact state between an input disk and an output disk, and a toroidal speed change mechanism for controlling a driving torque of an engine. And a first transmission path for transmitting to the drive wheels using the planetary gear mechanism and a second transmission path for transmitting using only the toroidal transmission mechanism.
Transmission path switching means for selectively switching between the transmission path and the transmission path, and control means for controlling the toroidal transmission mechanism and the transmission path switching means in accordance with a shift characteristic set in advance based on the running state of the vehicle. A control device for a toroidal-type continuously variable transmission, wherein the control means switches the transmission path at a point where the first and second transmission paths have the same speed ratio. A transmission path switching means for controlling the transmission path switching means and controlling the toroidal transmission mechanism such that the same transmission ratio is maintained during the switching of the transmission path by the switching means. Control device. 2. The toroidal speed change mechanism has a trunnion that supports a roller, and the trunnion is moved relative to a disc by receiving a pressure difference between two hydraulic pressures, whereby the roller tilts. As a control valve for adjusting the differential pressure, a three-layer valve having a sleeve slidably housed in a valve body and a spool slidably housed in the sleeve is provided. As the sleeve of the three-layer valve slides in the valve body, the differential pressure with respect to the toroidal transmission mechanism is adjusted, and the control means changes the sleeve of the three-layer valve while the transmission path is being switched by the transmission path switching means. Controlling the toroidal transmission mechanism so that the same transmission ratio is maintained in the first and second transmission paths by fixing the inclination angle of the roller so as not to change. The control device for a toroidal-type continuously variable transmission according to claim 1, wherein: