JP2001041309A - Toroidal continuously variable transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain fail-safe at forward and backward traveling by certainly setting a geared neutral state, and to improve fuel consumption by extending a gear shift range as far as possible. SOLUTION: A hydraulic control system 51 is provided with a first and a second hydraulic control valves 60, 70. The first control valve 60 is provided with a regulating member 66 which regulates the movement of a sleeve 62 so as to exact shift control within only a ratio range of a forward traveling at a low mode and a low side at a high mode. The second control valve 70 is provided with a regulating member 76 which regulates the movement of a sleeve 72 so as to exact shift control within only a ratio range of a high side at the high mode and a backward traveling at the low mode.

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 technical field related to a geared neutral starting system.

[0002]

2. Description of the Related Art Hitherto, a toroidal-type continuously variable transmission of a geared neutral starting system has been known, and generally includes a toroidal transmission mechanism and a planetary gear mechanism. The toroidal speed change mechanism has an input disk connected to an engine output shaft, an output disk opposed to the input disk, and a power roller that is tiltably frictionally contacted between the input and output disks. The power roller is tilted steplessly between the input and output disks by the hydraulic control mechanism, so that the rotation of the input disk is steplessly changed and transmitted to the output disk.

[0003] The hydraulic control mechanism is, for example, a Japanese Patent Publication No. 7-1.
As shown in JP-A-13410, a sleeve provided in a casing and driven by a step motor, and a spool fitted in the sleeve and configured to feed back the amount of inclination of the power roller are provided. Hydraulic control valve (three-layer valve). The hydraulic control valve drives the piston by supplying different control hydraulic pressures to the two chambers of the hydraulic actuator having the two chambers defined by the pistons by moving the sleeve, and drives the pistons. The power roller is inclined by a predetermined amount. In the above-mentioned publication, when the input rotation to the toroidal transmission mechanism reverses during forward movement and reverse movement, two hydraulic control valves are provided so that they can be selectively used for forward movement and reverse movement.

On the other hand, the planetary gear mechanism includes a sun gear,
A planetary gear that meshes with the sun gear and revolves around the sun gear; a carrier that supports the planetary gear and rotates with the revolution of the planetary gear; and an internal gear that meshes with the planetary gear. This sun gear is connected to the output disk of the toroidal transmission mechanism, and the carrier is the first
The internal gear is connected to the transmission output shaft via the clutch. The sun gear (output disk) and the internal gear (transmission output shaft)
The second clutch is configured to be integrally rotated and fastened.

In the low mode, the first clutch is engaged and the second clutch is released to transmit the engine output to the transmission output shaft via the toroidal transmission mechanism and the planetary gear mechanism. On the other hand, in the high mode, the first clutch is disengaged and the second clutch is engaged to transmit the engine output to the transmission output shaft only through the toroidal transmission mechanism. I have.

Further, in the low mode, the forward, reverse and geared neutral states are achieved by controlling the speed ratio of the toroidal transmission mechanism. In other words, the carrier rotates at a constant rotational speed by the engine output shaft, while the sun gear rotates at the rotational speed changed by the toroidal transmission mechanism, and the rotational speed of the sun gear changes, thereby causing the internal gear (speed change). The rotation speed of the machine output shaft changes continuously from the forward side to the reverse side, and there is a point (geared neutral point) in the middle of which the rotation speed becomes zero.

[0007]

In the case where the geared neutral point exists as described above, in order to reliably set the geared neutral state and prevent the driver from moving forward and backward unintentionally, Shift control of the toroidal transmission mechanism by the hydraulic control mechanism must be performed accurately. However, step-out of the step motor of the hydraulic control valve or failure of the sensor or the like may occur, and it is difficult to reliably guarantee the geared neutral state. The same applies to the case where two hydraulic control valves are simply provided as described in the above-mentioned publication and used for forward and reverse.

Therefore, it is conceivable to provide a stopper for forcibly stopping the sleeve at the portion corresponding to the geared neutral point in each of the two hydraulic control valves for forward and reverse travel. However, merely providing the stopper limits the amount of inclination of the power roller, and thus cannot fully use the range in which the toroidal transmission mechanism can change the speed, and the range of the speed change is reduced.
For this reason, there is a problem that the maximum speed increase ratio is reduced particularly in the high mode, and the fuel efficiency is deteriorated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a hydraulic control mechanism for the above-described geared neutral start type toroidal type continuously variable transmission. It is an object of the present invention to improve the fuel economy by setting the gear shift neutral state assuredly and achieving forward-backward fail-safe, while widening the shift range as much as possible.

[0010]

In order to achieve the above object, according to the first aspect of the present invention, the hydraulic control mechanism comprises a first hydraulic control valve and a second hydraulic control valve. A hydraulic pressure control valve is provided with a regulating portion that regulates control oil pressure so that shift control can be performed only in a ratio range between the forward side in the low mode and the low side in the high mode, while the second hydraulic control valve has In addition, a restricting portion for restricting the control oil pressure is provided so that the shift control can be performed only in the ratio range between the high side in the high mode and the reverse side in the low mode.

More specifically, according to the first aspect of the present invention, an input disk connected to the engine output shaft, an output disk opposed to the input disk, and a frictionally tiltable friction between the input and output disks. A toroidal transmission mechanism having a power roller to be contacted, a hydraulic control mechanism for driving the power roller of the toroidal transmission mechanism to a predetermined inclined position to control a speed ratio of the toroidal transmission mechanism, a sun gear, and a sun gear; A planetary gear that meshes with a gear and revolves around the sun gear, a carrier that supports the planetary gear and rotates with the revolution of the planetary gear, and an internal gear that meshes with the planetary gear; Two components of the carrier and the internal gear are connected to the engine output shaft in a state via the toroidal transmission mechanism and in a state not through the toroidal transmission mechanism, respectively. And a planetary gear mechanism connected to the transmission output shaft, and transmits an engine output to the transmission output shaft via the toroidal transmission mechanism and the planetary gear mechanism in the low mode. On the other hand, in the high mode, the engine output is configured to be transmitted to the transmission output shaft only through the toroidal transmission mechanism, and by controlling the speed ratio of the toroidal transmission mechanism in the low mode, the forward, It is intended for a geared neutral start type toroidal type continuously variable transmission that achieves reverse and geared neutral states.

The hydraulic control mechanism includes a first hydraulic control unit having a control unit that controls the control hydraulic pressure so that the shift control can be performed only in a ratio range between the forward side in the low mode and the low side in the high mode. A second control valve having a control valve and a restricting portion for restricting a control hydraulic pressure so as to perform a shift control only in a ratio range between a high side in a high mode and a reverse side in a low mode
And a hydraulic control valve.

With the above arrangement, the geared neutral state can be reliably set by the respective restricting portions of the first and second hydraulic control valves. On the other hand, the control range of the first hydraulic control valve is limited by the restricting portion, and the shift control can be performed only in the low ratio range in the high mode,
In the high-side ratio range in the high mode, the shift control is performed by the second hydraulic control valve that controls the reverse side, so that the range in which the gear can be shifted by the toroidal transmission mechanism can be fully used. Therefore, it is possible to improve the fuel efficiency while achieving the forward-backward fail-safe.

According to a second aspect of the present invention, in the first aspect of the present invention, the first and second hydraulic control valves are both formed of three-layer valves.

Thus, the amount of inclination of the power roller can be fed back, and a hydraulic control valve most suitable for speed change control of the toroidal speed change mechanism can be obtained.

According to a third aspect of the present invention, in the second aspect of the present invention, the engine output shaft and a component connected to the engine output shaft in the planetary gear mechanism without the intermediary of the toroidal speed change mechanism are pressure-operated. When the high mode is switched from the low side to the high side, the hydraulic control path of the toroidal transmission mechanism is switched from the first hydraulic control valve to the second hydraulic control valve. It is assumed that the operating pressure in the control path of the clutch is drained.

That is, on the low side in the high mode, it is necessary to hold the operating pressure in the control path of the clutch in preparation for switching to the low mode so that the clutch can be operated immediately. On the high side in the high mode, there is no need to do so. Conversely, if an abnormality occurs in a solenoid or the like for supplying the operating pressure to the clutch and the clutch operates, the vehicle may move backward. But,
According to the present invention, since the operating pressure in the control path of the clutch is drained on the high side in the high mode, the clutch does not operate erroneously and the low mode is not performed, and it is ensured that the transmission is shifted erroneously to the reverse side. Can be prevented.

According to a fourth aspect of the present invention, in the second aspect of the present invention, the engine output shaft and the component connected to the engine output shaft in the planetary gear mechanism without the intermediary of the toroidal speed change mechanism are pressure-operated. And when the reverse is selected during forward travel, the operating pressure in the control path of the clutch is drained until the vehicle speed during forward travel falls below a predetermined value. Shall be

As a result, the clutch does not operate even if the driver selects reverse by using the select lever while the vehicle is moving forward at a vehicle speed higher than the predetermined value, and the vehicle does not go into reverse. As a result, it is possible to prevent the transmission from being damaged due to a driver's erroneous operation.

According to a fifth aspect of the present invention, an input disk connected to an engine output shaft, an output disk disposed opposite to the input disk, and a power roller that is tiltably frictionally contacted between the input and output disks. A toroidal transmission mechanism having: a hydraulic control mechanism that drives a power roller of the toroidal transmission mechanism to a predetermined inclined position to control a transmission ratio of the toroidal transmission mechanism; a sun gear; and a sun gear that meshes with the sun gear. A planetary gear that revolves around the gear,
A carrier that supports the planetary gears and rotates with the revolution of the planetary gears; and an internal gear that meshes with the planetary gears, wherein one of the sun gear and the internal gear is the toroidal gear with respect to the engine output shaft. A planetary gear mechanism that is connected to the transmission output shaft while being connected via a transmission mechanism, and the carrier is connected to the engine output shaft without passing through the toroidal transmission mechanism,
In the low mode, the engine output is transmitted to the transmission output shaft via the toroidal transmission mechanism and the planetary gear mechanism, while in the high mode, the engine output is transmitted to the transmission output shaft via the toroidal transmission mechanism only. The present invention is directed to a toroidal-type continuously variable transmission of a geared neutral starting system that is configured to transmit and control a gear ratio of the toroidal transmission mechanism in the low mode to achieve a geared neutral state.

The gear ratio of each gear of the planetary gear mechanism is set so that the maximum speed change point of the toroidal speed change mechanism is a geared neutral point, and a brake for fixing the carrier of the planetary gear mechanism so as not to rotate. Shall be provided.

According to the present invention, the geared neutral state can be reliably set by moving the sleeve of the hydraulic control valve to one end without providing the restricting portion in the hydraulic control valve, and furthermore, the shift range. Can be widely taken. On the other hand, if the carrier of the planetary gear mechanism is fixed by the brake so as not to rotate, the sun gear and the internal gear always rotate in opposite directions to each other, so that it is possible to easily bring the vehicle into reverse. Therefore, the same operation and effect as those of the first aspect of the invention can be obtained, and the forward and reverse speed change control can be performed by one hydraulic control valve, and the regulation part is not required, so that the cost can be reduced.

[0023]

(Embodiment 1) FIG. 1 shows a schematic configuration of a toroidal type continuously variable transmission according to Embodiment 1 of the present invention. This transmission has a toroidal transmission mechanism 1 and a planetary gear mechanism 2. And This toroidal transmission mechanism 1
Two input disks 6 and 6 connected to an engine output shaft 5 extending in the left-right direction of the drawing (the engine is not shown, but is provided at the right end of the engine output shaft 5).
And output disks 7, 7 arranged opposite to the input disks 6, 6, respectively. Opposing surfaces of the input / output disks 6 and 7 are formed as toroidal curved surfaces,
Between the opposing surfaces of the input / output disks 6 and 7, two power rollers 8 and 8 that are frictionally contacted so as to be tiltable are symmetrically arranged with respect to the axis of the engine output shaft 5.

The input disks 6, 6 are arranged at both axial ends of the engine output shaft 5 with respect to the output disks 7, 7, and are connected to the engine output shaft 5 via ball splines (not shown). On the other hand, it is locked in the rotation direction and mounted so as to be able to move smoothly in the axial direction. A loading cam device 11 is provided on the left side of the input disk 6 on the left side of the engine output shaft 5. The loading cam device 11 receives an engine rotation from the engine output shaft 5, and generates an engine according to the input torque. A pressing force in a direction along the output shaft 5 is generated. Although not shown, a disc spring is provided between the right input disk 6 and the engine output shaft 5 so that the pressing force generated by the loading cam device 11 is applied to the left input disk 6. In addition to the action, it also acts on the right input disk 6 via the engine output shaft 5 and the disc spring, and similarly, the pressing force of the disc spring also acts on both input discs 6, 6.

On the other hand, the respective output disks 7 are fitted to the engine output shaft 5 so as to be rotatable relative to each other, and are integrally connected to each other on the side opposite to the opposing surface of the respective input disks 6. At the same time, it is rotatably coupled to the first output gear 15 on the outer peripheral surface. This first output gear is
The rotational force transmitted from each input disk 6 to each output disk 7 via each power roller 8 is transmitted to the second output gear 16.

The planetary gear mechanism 2 includes a sun gear 21 and
A plurality of planetary gears 22, 22, ... which mesh with the sun gear 21 and revolve around the sun gear 21;
Carrier 2 that supports the planetary gears 2 and rotates with the revolution of the planetary gears 22, and an internal gear 24 that meshes with each planetary gear 22
It is composed of The internal gear 24 is connected to a connection member 27 provided integrally with the transmission output shaft 28 so as to rotate. The sun gear 21 is connected to the second output gear 16, and the second output gear 16 is connected to the transmission output shaft 28.
Are fitted so as to be relatively rotatable. That is, the sun gear 21 is connected to the engine output shaft 5 via the toroidal transmission mechanism 1. On the other hand, the carrier 23 is connected to the engine output shaft 5 without interposing the toroidal transmission mechanism 1. That is, a first transmission gear 30 is provided at the left end of the engine output shaft 5 so as to rotate integrally therewith, and the second transmission gear 31 is meshed with the first transmission gear 30.
The second transmission gear 31 is meshed with a third transmission gear 32 fitted to be rotatable relative to the transmission output shaft 28. And, the third transmission gear 3
Between the carrier 2 and the carrier 23, there is provided a hydraulically operated first clutch 41 which can be freely engaged and disengaged, and the third transmission gear 32 and the carrier 23 are separated by the operation of the first clutch 41. They are connected and rotate integrally.

The second output gear 16 and the transmission output shaft 28
And a hydraulically operated second clutch 42 that can be freely engaged and released.
Is fastened, the second output gear 16 (sun gear 21) and the transmission output shaft 28 (internal gear 24) are connected and rotate integrally.

In the low mode, the first clutch 41 is engaged and the second clutch 42 is released, as will be described later, so that the rotation of the engine output shaft 5 is prevented from being toroidal. Transmission mechanism 1 and first
The transmission is transmitted to the sun gear 21 of the planetary gear mechanism 2 via the second output gears 15 and 16, and is transmitted to the carrier 23 via the first to third transmission gears 30 to 32. 23 and the internal gear 24
, And the rotation of the internal gear 24 is transmitted to the transmission output shaft 28 via the connecting member 27. That is, in the low mode, the engine output is transmitted to the transmission output shaft 28 via the toroidal transmission mechanism 1 and the planetary gear mechanism 2.

On the other hand, in the high mode, the first
Is disengaged and the second clutch 42 is engaged, which allows the engine output shaft 5
Is transmitted to the transmission output shaft 28 via the toroidal transmission mechanism 1 and the first and second output gears 15 and 16. That is, in the high mode, the engine output is transmitted only through the toroidal transmission mechanism 1 to the transmission output shaft 2.
8.

In the low mode, the forward, reverse and geared neutral states are achieved by controlling the speed ratio of the toroidal transmission mechanism 1 as described later. That is, as shown in the planetary velocity diagram of FIG. 3, the carrier 23 rotates at a constant rotation speed N0 similarly to the engine output shaft 5, while the sun gear 21 (the second output gear 16) is rotated by the toroidal transmission mechanism 1. The sun gear 2 rotates at the changed rotation speed (N0 to N2).
1 increases from N0 to N2, the rotation speed of the internal gear 24 (transmission output shaft 28) becomes N
There is a point (the GN point in FIG. 3: a geared neutral point in FIG. 3) that continuously changes from 0 (forward) to the reverse side and the rotation speed becomes 0 on the way (the sun gear 21 at this time).
Is the rotation speed of N1). In FIG. 3, X is (number of teeth of the internal gear 24) / (number of teeth of the sun gear 21).
= (N1-N0) / N0.

As shown in FIG. 2, each power roller 8 of the toroidal transmission mechanism 1 is steplessly inclined between the input and output disks 6 and 7 by the hydraulic control mechanism 51. The speed of the rotation of the planetary gear mechanism is steplessly transmitted and transmitted to each output disk 7, and the sun gear 2
1 can be set to any value of N0 to N2.

The hydraulic control mechanism 51 includes hydraulic actuators 52 provided corresponding to the respective power rollers 8. Each of the hydraulic actuators 52
The upper chamber 54 and the lower chamber 55 are defined by a piston 53. The upper chamber 54 and the lower chamber 55 are connected to each other from one of first and second hydraulic control valves 60 and 70 described later. The piston 53 moves up and down by supplying different control oil pressures. The piston 53 is provided with a rotating shaft 56 that moves up and down together with the piston 53. Each of the power rollers 8 is rotatably mounted on each of the rotary shafts 56 via an eccentric shaft 57, and each power roller 8 is tilted by the vertical movement of each of the rotary shafts 56. At this time, each of the rotating shafts 56 rotates when each of the power rollers 8 is tilted due to the vertical movement of each of the rotating shafts 56, whereby the amount of tilt (tilting) of each of the power rollers 8 is adjusted. The angle) is determined by the amount of operation of each hydraulic actuator 52 (the amount of vertical movement of the rotary shaft 56), and in turn, the amount of rotation of the rotary shaft 56. In FIG. 1, the two left power rollers 8, 8 are inclined in the opposite direction by the same amount, and the two right power rollers 8, 8 are also inclined in the opposite directions by the same amount. The output disk 7 and the right output disk 7 have the same rotational speed.

When the rotational speed of each of the input and output disks 6 and 7 is the same as the reference (0), the inclination amount of each power roller 8 is -α to + β (the output disk 7 is The speed increasing side is defined as minus and the deceleration side is defined as plus. In the first embodiment, | -α |>
When the amount of inclination is -α, the rotation speed of the second output gear 16 (the sun gear 21 of the planetary gear mechanism 2) becomes N2, and when the amount of inclination is + β, it becomes N0.
Becomes Further, the amount of inclination when the rotation speed of the second output gear 16 becomes N1 (corresponding to the geared neutral point) is:
−γ (> −α). In the following description, when the magnitude of the inclination of each power roller 8 is referred to,
It shall include plus and minus, not absolute values.

In the high mode, when the inclination of each power roller 8 is increased from -α to + β, the rotation speed of the second output gear 16, that is, the rotation speed of the transmission output shaft 28 is increased. From N2 to N0,
When the inclination amount is + β, the mode is switched to the low mode, and the inclination amount is reduced from + β to −γ this time.
The rotation speed of the output gear 16, that is, the rotation speed of the sun gear 21 increases from N0 to N2. As a result, the rotation speed of the internal gear 24, that is, the rotation speed of the transmission output shaft 28 decreases from N0 to 0. Become. Then, when the inclination amount is further reduced from -γ to -α in the low mode, the transmission output shaft 28 rotates in the reverse direction and moves backward, and at the same time, the backward moving speed increases.

The hydraulic control mechanism 51 further includes first and second hydraulic control valves 60 and 70 and both hydraulic control valves 6 and 70.
0 and 70, and the upper chamber 54 and the lower chamber 5 of each of the hydraulic actuators 52 are selected from the selected one.
Switching valve 80 configured to supply control hydraulic pressure to the control valve 5
A manual valve 91 having a spool 91a that moves in the axial direction in conjunction with a select lever operable by a driver; and first and second shift valves 92 and 93.

The first and second hydraulic control valves 60, 70
Are the same and consist of a three-layer valve. That is, the first and second hydraulic control valves 60 and 70 are composed of substantially cylindrical casings 61 and 71 and casings 61 and 7.
Sleeve 1 reciprocally movable in the axial direction within 1
2,72, and sleeves 62,72 in the sleeves 62,72.
72, and spools 63 and 73 provided so as to be able to reciprocate in the axial direction with respect to 72. The above sleeves 62 and 72
The inner peripheral portion of the left end of the casing is screwed with drive rods 65 and 75 which are driven to rotate by step motors 64 and 74. The outer peripheral portion of the left end of the Engagement projections 62a and 72a are provided for engagement with the provided grooves 61a and 71a. Thus, when the drive rods 65 and 75 are rotated by the step motors 64 and 74, the sleeves 62 and 72 can move in the axial direction without rotating.

At the right end of the spools 63 and 73,
Notch 63 engaged with one end of an interlocking member (not shown)
a, 73a, and the other end of this interlocking member is
Are connected to one of the rotating shafts 56, 56,..., And the amount of vertical movement of the rotating shaft 56, that is, the amount of inclination of each power roller 8 is fed back.

The sleeves 62 and 72 have line pressure introduction ports 62b and 72b through which line pressure is introduced.
With the movement of the sleeves 62 and 72 with respect to the spools 63 and 73, the line pressure introduction ports 62b and 72b
First outlet port 62 for distributing the line pressure from the outlet port
c, 72c and second outlet ports 62d, 72d, and when in a stable state, the line pressure is equally distributed to the first outlet ports 62c, 72c and the second outlet ports 62d, 72d. The first outlet ports 62c, 72
c is the first and second introduction ports 80b of the switching valve 80,
80c, and the second outlet port 62
d and 72d are third and fourth introduction ports 80 of the switching valve 80.
d, 80e.

The switching valve 80 has a first communication port which communicates with one of the first and second introduction ports 80b and 80c.
The outlet port 80f and the third and fourth inlet ports 80
Second outlet port 8 communicating with one of d and 80e
0 g is provided. The first outlet port 80f of the switching valve 80 is connected to one of the upper chamber 54 and the lower chamber 55 of each of the hydraulic actuators 52 via the first output line 81, and the second outlet port 80g is connected to the second output line. It is connected to the other via 82. In FIG. 2, the first and second output lines 81 and 82 are connected to only one hydraulic actuator 52. However, in practice, the first and second output lines 81 and 82 are branched into four on the way to form four hydraulic actuators 52 and 82.
52,... Are connected to all. Also, in the same figure, the first output line 81 is connected to the upper chamber 54 of the hydraulic actuator 52,
The second output lines 82 are connected to the lower chamber 55, respectively.
The two hydraulic actuators 52, 52 corresponding to the two power rollers 8, 8, respectively, are reversed.

The switching valve 80 controls the speed change only in the ratio range between the forward side when the first hydraulic control valve 60 is in the low mode and the low side when the first hydraulic control valve 60 is in the high mode. Is switched only in the ratio range between the high side in the high mode and the reverse side in the low mode. In the state of FIG. 2, the spool 80a is shifted to the right by a spring (not shown) and The first and second outlet ports 80f, 80g are first and third introduction ports 80b, 80, respectively.
d and the first hydraulic control valve 6
0 indicates that the tilt amount of each power roller 8 can be controlled. On the other hand, when a line pressure is introduced into the control port 80h provided in the switching valve 80 as described later, the spool 80a of the switching valve 80 moves to the left, and the first and second outlet ports 80f and 80g are moved to the left. The second and fourth introduction ports 80c and 80e are in communication with each other.
The state in which the amount of inclination of each power roller 8 can be controlled by the hydraulic control valve 70 of FIG.

The sleeve 61 is formed in the groove 61a on the inner peripheral surface of the casing 61 of the first hydraulic control valve 60 so that the inclination amount of each power roller 8 can be set only in the range of -γ to + β. A restricting member 66 for restricting the movement of 62 is provided. In other words, even if the inclination amount of each power roller 8 is to be made smaller than -γ, the engagement protrusion 62a of the sleeve 62 abuts on the regulating member 66 and cannot move further rightward. It is restricted so that only the forward control can be performed in the low mode and only the low control can be performed in the high mode.

On the other hand, between the sleeve 72 and the step motor 74 of the second hydraulic control valve 70, the amount of inclination of each power roller 8 can be set only in the range of -α to -γ. A regulating member 76 for regulating the movement of the sleeve 72 is provided. In other words, even if the inclination amount of each power roller 8 is to be made larger than -γ, the sleeve 72 abuts on the regulating member 76 and cannot move further leftward, so that the control oil pressure is regulated. Only the reverse side control can be performed, and only the high side control can be performed in the high mode.

The line pressure is obtained by adjusting the pressure of the hydraulic oil discharged from the hydraulic pump 86 in the main line 85 to a predetermined value by the regulator valve 87.
The regulator valve 87 is also connected to a lubrication line 88 for each of the power rollers 8 and the like, so that hydraulic oil is also supplied to each of the power rollers 8 and the like.
The sleeve 6 of the first and second hydraulic control valves 60, 70
In the parts 2 and 72, a relief pressure whose pressure is adjusted to a considerably lower pressure by the control valve 90 is introduced into the right part of the first outlet ports 62c and 72c and the left part of the second outlet ports 62d and 72d. Pressure introduction ports 62e and 72e are provided.

The line pressure is adjusted by the manual valve 9
It is also supplied to one line pressure introduction port 91b. When the select lever is set to neutral (N range) or parking (P range), the line pressure introduction port 91b is provided with first and second outlet ports 91c provided on both axial sides of the line pressure introduction port 91b. , 91d
In the state set to the forward (D range), only the first outlet port 91c is communicated, and in the state set to the reverse (R range), the second outlet port 9 is set.
It is configured to communicate with only 1d.

The first outlet port 91c of the manual valve 91 is connected to the first inlet port 92b of the first shift valve 92, and the second outlet port 91d of the manual valve 91 is connected to the second outlet port of the first shift valve 92. The introduction port 92c is connected to the fourth introduction port 93e and the control port 93h of the second shift valve 93. When line pressure is supplied to the control port 93h of the second shift valve 93, the spool 93a which has been moved to the right by a spring (not shown) moves to the left. Also, the first to third lead-out ports 92 of the first shift valve 92
d, 92e, and 92f are connected to the third introduction port 93d, the first introduction port 93b, and the second introduction port 93c of the second shift valve 93, respectively. Further, a pressure reducing line 9 is connected to a control port 92g of the first shift valve 92.
The pressure reducing line 95 is provided with an ON / OFF solenoid 96. The ON / OFF solenoid 96 pressurizes the operating oil at a constant pressure reduced by a predetermined amount below the line pressure by the reducing valve 97.
When the ON / OFF solenoid 96 is turned on, the constant pressure reduction is supplied to the control port 92g of the first shift valve 92, and the spool is moved to the left by a spring (not shown). The constant decompression is not supplied to the control port 92g when the switch 92a is moved to the right while it is in the OFF state.

The second outlet port 93g of the second shift valve 93 is connected to the control port 80h of the switching valve 80, and connects the manual valve 91 and the first and second shift valves 92 and 93 as described later. The line pressure is supplied to the control port 80h of the switching valve 80 via the switching valve 80.

The first outlet port 93f of the second shift valve 93 is connected to the first clutch 41 via a first clutch control line 101. A first duty solenoid 102 is provided in the middle of the first clutch control line 101. The line pressure is supplied to the first duty solenoid 102, and the first duty solenoid 102 operates (when the low duty mode is set). ), The line pressure (or the adjustment pressure reduced from the line pressure by the ON / OFF duty ratio) is supplied to the first clutch 41, and the first clutch 41 is brought into the engaged state. I have. Note that a first accumulator 103 is provided between the first clutch 41 and the first duty solenoid 102 in the first clutch control line 101.

The second outlet port 91d of the manual valve 91 is connected to the second clutch 42 via a second clutch control line 106. In the middle of the second clutch control line 106, a second duty solenoid 107 is provided. When the line pressure is supplied to the second duty solenoid 107, the second duty solenoid 107 operates (when the high duty mode is set). ), The line pressure (or the adjusted pressure reduced from the line pressure by the ON / OFF duty ratio) is supplied to the second clutch 42 and the second clutch 42
2 is in a fastening state. Note that the first clutch control line 106 is provided between the second clutch 42 and the second duty solenoid 107.
A second accumulator 108 similar to accumulator 103 is provided.

The operation of the toroidal type continuously variable transmission having the above configuration will be described. FIG. 4 shows a state in which the select lever is set to the N range or the P range. In this state (geared neutral state), the engagement protrusion 62 a of the sleeve 62 of the first hydraulic control valve 60 The sleeve 72 of the second hydraulic control valve 70 is in contact with the regulating member 76. Then, the sleeves 62, in the first and second hydraulic control valves 60, 70,
Line pressure is supplied to the line pressure introduction ports 62b and 72b of the line 72 (the cross-hatched portion in the hydraulic line of FIG. 4 is the portion to which the line pressure is supplied (see FIGS. 5 to 8). This is the same), but this line pressure is equally distributed to the first outlet ports 62c and 72c and the second outlet ports 62d and 72d. The spool 80a of the switching valve 80 is shifted to the right,
The second outlet ports 80f and 80g communicate with the first and third inlet ports 80b and 80d, respectively, so that the first hydraulic control valve 60 can control the amount of tilt of each power roller 8. However, the first hydraulic control valve 6
0, the first outlet port 62c and the second outlet port 62
Since the pressure d is equal to the pressure PH in the first output line 81 and the pressure PL in the second output line 82, there is no pressure difference between the upper chamber 54 and the lower chamber 55 of each hydraulic actuator 52. The tilt amount of each power roller 8 is maintained at -γ.

Further, the line pressure is controlled by the manual valve 9.
Although it is also supplied to the first line pressure introduction port 91b, this line pressure introduction port 91b is not in communication with either of the first and second derivation ports 91c and 91d. And second shift valves 92, 9
3 and the first and second clutches 41 and 42 are not drained and are in a drained state.

Further, a constant pressure reduction O
It is supplied to the N / OFF solenoid 96 (the hatched portion in the hydraulic line of FIG. 4 is a portion to which a constant reduced pressure is supplied (FIGS. 5 to 8).
The same applies to the above))), but this ON / OFF solenoid 9
6 is in the OFF state, and the constant decompression is not supplied to the control port 92g of the first shift valve 92.

Next, when the driver sets the select lever to the D range, the mode is set to the low mode when the vehicle speed is low, and the first clutch 41 is engaged and the second clutch 42 is engaged as described below. In the open state, the engine output is transmitted to the transmission output shaft 28 via the toroidal transmission mechanism 1 and the planetary gear mechanism 2.

That is, as shown in FIG. 5, the spool 91a of the manual valve 91 moves to the right side of the N range or the P range by the operation of the select lever, and the line pressure introduction port 91b is moved to the first outlet. It communicates only with the port 91c. As a result, the line pressure is introduced into the first introduction port 92b of the first shift valve 92,
Since the first introduction port 92b communicates with the second outlet port 92e (the ON / OFF solenoid 96 is turned off).
The spool 9 of the first shift valve 92 remains in the state.
The line pressure is introduced into the first introduction port 93b of the second shift valve 93. The first introduction port 93b of the second shift valve 93 is connected to the first
Since it is in communication with the outlet port 93f, the first duty solenoid 10
Line pressure is supplied to the point 2. Since the low mode is set, the first duty solenoid 102 operates, and the line pressure is supplied to the first clutch 41. On the other hand, although the line pressure is also supplied to the second duty solenoid 107 in the second clutch control line 106, the second duty solenoid 107 is not operated, and the line pressure is supplied to the second clutch 42. Not done. Therefore, the first clutch 4
1 is in the engaged state, and the second clutch 42 is in the released state.

During forward traveling in the low mode, as the vehicle speed increases, the amount of inclination of each power roller 8 becomes -γ.
From. That is, the sleeve 62 of the first hydraulic control valve 60 is moved leftward by the step motor 64, and the first outlet port 62c is moved to the second outlet port 6c.
The pressure becomes higher than 2d, the pressure PH in the first output line 81 becomes higher than the pressure PL in the second output line 82, and the pressure difference between the upper chamber 54 and the lower chamber 55 of each hydraulic actuator 52 is reduced. As a result, the amount of inclination of each power roller 8 increases. The amount of tilt of each power roller 8 is determined by the spool 6
3 when the set position is reached and the stepping motor 64 is stopped, eventually the spool 63
Also moves to the left by the same amount as the sleeve 62 and becomes stable again.

On the other hand, when the amount of inclination of each power roller 8 is controlled by the first hydraulic control valve 60, the sleeve 72 of the second hydraulic control valve 70 is moved to the right by the step motor 74. At this time, the spool 73 of the second hydraulic control valve 70 moves to the left in conjunction with the spool 63 of the first hydraulic control valve 60 by an interlocking member for feeding back the amount of inclination of each power roller 8. Therefore, the line pressure introduction port 72b and the second outlet port 72
d is completely communicated, and the line pressure is introduced into the fourth introduction port 80e of the switching valve 80. Also, the right relief pressure introduction port 72e and the first outlet port 72c on the right side.
The relief pressure is introduced into the second introduction port 80c of the switching valve 80. However, the second and fourth introduction ports 80c and 80e are not connected to the first and second outlet ports 80.
The line pressure and the relief pressure are not supplied to the hydraulic actuators 52 because they are not communicated with the hydraulic actuators f and 80g, respectively.

Subsequently, the amount of inclination of each power roller 8 is + β
When the vehicle speed further increases at the stage when the vehicle speed has reached, the high mode is set. That is, as shown in FIG. 6, the second duty solenoid 107 operates to supply line pressure to the second clutch 42 to bring the second clutch 42 into the engaged state, while the first duty solenoid 102 does not operate. In this state, the first clutch 41 is released, and the engine output is transmitted to the transmission output shaft 28 only through the toroidal transmission mechanism 1. On the low side of the high mode, the line pressure is supplied up to the first duty solenoid 102 in the first clutch control line 101, so that the high mode can be immediately switched to the low mode. Conversely, on the forward side of the low mode, the second clutch control line 10
Since the line pressure is supplied to the second duty solenoid 107 at 6, the switching from the low mode to the high mode is also performed immediately.

In the high mode, as the vehicle speed increases, the amount of inclination of each power roller 8 decreases from + β. That is, the sleeve 62 of the first hydraulic control valve 60 is moved rightward by the step motor 64 this time, and the pressure of the second outlet port 62d becomes higher than that of the first outlet port 62c. Conversely, the amount of inclination of each power roller 8 is reduced.

When the amount of inclination of each power roller 8 reaches -γ again, the engaging projection 62a of the sleeve 62 of the first hydraulic control valve 60 comes into contact with the regulating member 66 and the N range or the P range. (The second hydraulic control valve 70 is also in the same state as the N range or the P range),
For this reason, the first hydraulic control valve 60 controls each power roller 8
Cannot be made smaller than -γ.
Therefore, when the vehicle speed further increases, the hydraulic control path is switched from the first hydraulic control valve 60 to the second hydraulic control valve 70, and the amount of inclination of each power roller 8 is changed to the second hydraulic control valve 7
0 is controlled. That is, the shift control is performed by the first hydraulic control valve 60 in the low ratio range in the high mode, and the shift control is performed by the second hydraulic control valve 70 in the high ratio range in the high mode.

More specifically, as shown in FIG.
The FF solenoid 96 is turned on, a constant pressure is supplied to the control port 92g of the first shift valve 92, and the spool 92a is moved to the right. Therefore, the first inlet port 92b of the first shift valve 92 is connected to the first outlet port 9
2d, and the line pressure is the third pressure of the second shift valve 93.
It is supplied to the introduction port 93d. Since the third inlet port 93d of the second shift valve 93 is in communication with the second outlet port 93g, the line pressure becomes lower than the second pressure.
The supply port 93g is supplied to the control port 80h of the switching valve 80, and the spool 80a of the switching valve 80 moves to the left. As a result, the first and second outlet ports 8 of the switching valve 80
0f and 80g are the second and fourth introduction ports 80c and 80e.
And the second hydraulic control valve 70 can control the amount of inclination of each power roller 8.

The spool 92 of the first shift valve 92
By moving a to the right, the second outlet port 92e communicates with the drain port, so that the line pressure (operating pressure) in the first clutch control line 101 is drained. As a result, even if the first duty solenoid 102 malfunctions, the first clutch 41 will not be in the engaged state, and will never be in the low mode. In other words, when the low mode is entered at this stage, the state becomes the same as a reverse state described later. Therefore, the line pressure in the first clutch control line 101 is drained, so that an erroneous shift to the reverse side is reliably prevented. In addition, by operating both the first and second clutches 41 and 42, it is possible to prevent an abnormally large force from being generated in each component of the planetary gear mechanism 2.

On the high side of the high mode, the inclination of each power roller 8 decreases as the vehicle speed increases.
Reduced from γ. That is, the sleeve 72 of the second hydraulic control valve 70 is moved rightward by the step motor 74, the pressure of the second outlet port 72d is higher than that of the first outlet port 72c, and the inclination of each power roller 8 is increased. The amount is smaller. As in the case of the first hydraulic control valve 60, the amount of inclination of each power roller 8 is fed back to the spool 73, and when the set motor reaches the set position and the step motor 74 is stopped, the spool 73 eventually becomes a sleeve. It moves to the right by the same amount as 72 and is again in a stable state.

On the other hand, when the amount of inclination of each power roller 8 is controlled by the second hydraulic control valve 70, the first hydraulic control valve 60 moves the sleeve 62 to the left by the step motor 64. At this time, the spool 63 of the first hydraulic control valve 60 moves to the right in conjunction with the spool 73 of the second hydraulic control valve 70, so that the line pressure introduction port 62b and the first outlet port 62c are completely The communication state is established, and the line pressure is introduced into the first introduction port 80b of the switching valve 80. Further, the relief pressure introduction port 62e on the left side communicates with the second outlet port 62d, and the relief pressure is introduced into the third introduction port 80d of the switching valve 80. However, the first and third introduction ports 80b, 80
Since d does not communicate with the first and second outlet ports 80f and 80g, the line pressure and the relief pressure are not supplied to the hydraulic actuators 52.

Next, the inclination of each power roller 8 is -α.
Is reached, the transmission output shaft 28 is in the state of maximum speed change, and no further speed change is possible. When the sleeve 72 of the second hydraulic control valve 70 is moved leftward by the step motor 74 from this state, the pressure of the first outlet port 72c becomes higher than that of the second outlet port 72d, and each power The amount of inclination of the roller 8 increases. Then, when the amount of inclination of each power roller 8 reaches -γ again, the sleeve 72 of the second hydraulic control valve 70 comes into contact with the regulating member 76 to be in the same state as the N range or the P range. When decelerating further from this state, the hydraulic control path is switched from the second hydraulic control valve 70 to the first hydraulic control valve 60, and control is performed in the same manner as described above according to the high mode and the low mode.

Then, when the amount of inclination of each power roller 8 is reduced in the low mode, the power amount reaches −γ, and the engagement projection 62 a of the sleeve 62 of the first hydraulic control valve 60 moves to the regulating member 66. Abut Therefore, the first
The reverse speed change control cannot be performed with the hydraulic control valve 60 of
The geared neutral state can be reliably set.

On the other hand, when the select lever is set to the R range, the hydraulic control path is moved from the first hydraulic control valve 60 to the second hydraulic control valve.
And the amount of inclination of each power roller 8 is controlled by the second hydraulic control valve 70. That is,
The ratio range on the forward side in the low mode is the first hydraulic control valve 6
The shift control is performed by 0, and the shift control is performed by the second hydraulic control valve 70 in the ratio range on the reverse side in the low mode.

More specifically, when the select lever is set to the R range, the spool 91a of the manual valve 91 is set to N by operating the select lever as shown in FIG.
It moves to the left from the range or the P range, and the line pressure introduction port 91b communicates only with the second derivation port 91d. Thus, the line pressure is supplied to the second introduction port 92c of the first shift valve 92 and the fourth introduction port 93e and the control port 93h of the second shift valve 93,
Since the second introduction port 92c of the first shift valve 92 is in communication with the third lead-out port 92f (ON / OFF
The solenoid 96 remains OFF, and the spool 92a of the first shift valve 92 is shifted to the left.) The line pressure is also supplied to the second introduction port 93c of the second shift valve 93. On the other hand, when the line pressure is supplied to the control port 93h of the second shift valve 93, the spool 93a of the second shift valve 93 shifts to the left side. 4 introduction ports 93c and 93e are the first and second outgoing ports 93
The line pressure is supplied to the first duty solenoid 102 in the first clutch control line 101 in communication with f and 93g. Since the low mode is set, the first duty solenoid 1
02 operates, and the line pressure is supplied to the first clutch 41. Further, the line pressure is also introduced into the control port 80h of the switching valve 80 via the fourth introduction port 93e and the second outlet port 93g of the second shift valve 93, and the switching valve 80 is shifted to the left side, and the second The hydraulic control valve 70 controls the amount of inclination of each power roller 8 in the range of -α to -γ.

The spool 91 of the manual valve 91
By moving a to the left, the first outlet port 91c communicates with the drain port, so that the line pressure in the second clutch control line 106 is drained. As a result, even if the second duty solenoid 107 malfunctions, the second clutch 42 will not be in the engaged state, and will never be in the high mode. That is, when the high mode is entered at this stage, the state becomes the same as the forward state as described above. Therefore, the line pressure in the second clutch control line 106 is drained, whereby the erroneous shift to the forward side is reliably prevented. .

When the selector lever is set to the D range and the vehicle is running at a vehicle speed greater than a predetermined value, and when the selector lever is suddenly set to the R range, the ON / OFF solenoid 96 is turned on and the first A constant reduced pressure is supplied to the control port 92g of the shift valve 92. Thereby, the first
The communication between the second introduction port 92c and the third outlet port 92f of the shift valve 92 is interrupted, the line pressure in the first clutch control line 101 is drained, and the first clutch 41 does not operate. As a result, it is possible to prevent the transmission from being damaged due to an erroneous operation by the driver without suddenly entering the reverse state. Then, when the vehicle speed at the time of forward movement becomes equal to or less than a predetermined value, the ON / OFF solenoid 96 is turned off and the vehicle is set in the reverse state.

Therefore, in the first embodiment, the first hydraulic control valve 60 in the hydraulic control mechanism 51 for controlling the gear ratio by driving each power roller 8 of the toroidal transmission mechanism 1 to a predetermined inclined position is set to the low mode. A restricting member 66 for restricting the movement of the sleeve 62 so that the speed change control can be performed only in the ratio range between the forward side of the time and the low side in the high mode. Since it has the regulating member 76 that regulates the movement of the sleeve 72 so that the shift control can be performed only in the ratio range between the high side and the reverse side in the low mode, the geared neutral state can be reliably set. It is possible to prevent the driver from unintentionally moving forward or backward. On the other hand, the control range of the first hydraulic control valve 60 is limited by the restricting member 66 so that the shift control can be performed only in the low-side ratio range in the high mode, but the high-side ratio range in the high mode is Since the shift control is performed by the second hydraulic control valve 70 that controls the reverse side, the range in which the toroidal transmission mechanism 1 can shift can be fully used. Therefore,
Fuel economy can be improved while achieving forward-backward failsafe.

In the first embodiment, the planetary gear mechanism 2
The sun gear 21 is connected to the engine output shaft 5 via the toroidal transmission mechanism 1, the carrier 23 is connected to the engine output shaft 5 without the toroidal transmission mechanism 1, and the internal gear 24 Is connected to the transmission output shaft 28. However, the present invention is not limited to this. Two components of the sun gear 21, the carrier 23, and the internal gear 24 are connected to the engine output shaft 5 via the toroidal transmission mechanism 1. It is only necessary to connect the remaining one component to the transmission output shaft 28 in a state in which the transmission output shaft 28 is not interposed.

(Embodiment 2) FIGS. 9 and 10 show Embodiment 2 of the present invention (note that the same parts as those in FIGS. 1 and 2 are denoted by the same reference numerals and detailed description thereof is omitted). The gear ratio of the sun gear 21, the planetary gear 22, and the internal gear 24 of the planetary gear mechanism 2 is set so that the maximum speed change point of the toroidal speed change mechanism 1 is a geared neutral point.

That is, in the second embodiment, the hydraulic control mechanism 51 does not include the second hydraulic control valve 70 and the switching valve 80 in the first embodiment, and the first hydraulic control valve 60 (hereinafter, referred to as the first hydraulic control valve 60). Only the hydraulic control valve 60). Further, the hydraulic control valve 60 does not have the regulating member 66 as in the first embodiment. Then, the tilt amount of each power roller 8 is set to −α to + β (α) by the one hydraulic control valve 60 in both the forward high mode and the low mode.
And β are the same values as in the above embodiment) when the inclination amount of each power roller 8 becomes −α in the low mode (when the maximum shift point is reached).
In the geared neutral state, the mode is switched between the low mode and the high mode at + β. That is, when the inclination amount becomes −α in the low mode, the rotation speed of the second output gear 16 (sun gear 21) becomes the maximum at N2, and at this time, as shown by the solid line in FIG. The rotational speed of the transmission output shaft 28) is 0
Becomes Further, when the inclination amount becomes + β in the low mode, the rotation speed of the sun gear 21 becomes N0 and the rotation speed of the internal gear 24 also becomes N0, as in the first embodiment. In FIG. 11, Y is (number of teeth of the internal gear 24) /
(The number of teeth of the sun gear 21), and Y = (N2-N0) /
It becomes N0.

On the other hand, the carrier 23 of the planetary gear mechanism 2
The third clutch 43 fixes the carrier 23 to the housing 120 of the planetary gear mechanism 2 so as not to rotate.
(Brake) is provided. This third clutch 4
Numeral 3 is provided for reverse travel. When the third clutch 43 is engaged, the rotation speed of the carrier 23 becomes zero. Therefore, if the rotation speed at the point C in FIG. As can be seen, the internal gear 24 always rotates in the reverse direction (see the broken line in FIG. 11).

The hydraulic control mechanism 51 is provided in the first embodiment.
The manual valve 111 is provided with first and second line pressure introduction ports 111b and 111c into which line pressure is introduced, and the first and second line pressure introduction ports 111b are provided. , 1
11c is the first and second lead-out ports 111d, 111d, when the select lever is set to the N range or the P range.
111e is not communicated with each other. Then, when the D range is set, the spool 111
When a moves to the left by one step, the first and second line pressure introduction ports 111b and 111c communicate with the first and second derivation ports 111d and 111e, respectively, and the spool 111a is set in the R range. But one more
By moving to the left side of the stage, the second line pressure introduction port 1
11c only communicates with the second outlet port 111e, and the first line pressure introduction port 111b does not communicate with the first outlet port 111d.

The first outlet port 111d of the manual valve 111 is connected to the control port 11 of the shift valve 112.
When the line pressure is introduced into the control port 112e of the shift valve 112, the spool 112a which has been moved to the left by a spring (not shown) moves to the right.

The second outlet port 111e of the manual valve 111 is connected to the first duty solenoid 10
2 is connected to the introduction port 112b of the shift valve 112 via a connection line 115 provided. The introduction port 112b of the shift valve 112 is connected to the first outlet port 11 when the spool 112a is shifted to the right.
2c and the second outlet port 1 in the state shifted to the left side.
It communicates with 12d. The first outlet port 112c of the shift valve 112 is connected to the first clutch 41 via the first clutch control line 101. The first outlet port 111d of the manual valve 111 is also connected to the second clutch 42 via the second clutch control line 106. The second clutch control line 106 is provided with a second duty solenoid 107. Further, the shift valve 1
The twelve second outlet ports 112d are connected to the third clutch 43 via a third clutch control line 116. Note that this third clutch control line 116 also has
A third accumulator 117 similar to the first and second accumulators 103 and 108 is provided.

Next, the operation of the toroidal type continuously variable transmission will be described. FIG. 12 shows a state in which the select lever is set to the N range or the P range. In this state, the line pressure is supplied to the line pressure introduction port 62b of the sleeve 62 in the hydraulic control valve 60 (FIG. 12).
In this hydraulic line, the cross-hatched portion is the portion to which the line pressure is supplied (the same applies to FIGS. 13 to 15), and this line pressure is applied to the first outlet port 62c and the second outlet port 62d. Therefore, there is no pressure difference between the upper chamber 54 and the lower chamber 55 of each hydraulic actuator 52, and the amount of inclination of each power roller 8 is maintained at -α. The line pressure is controlled by the first and second line pressure introduction ports 11 of the manual valve 111.
1b and 111c, the first and second line pressure introduction ports 111b and 111c are not in communication with the first and second outlet ports 111d and 111e, respectively. It is not introduced into the valve 112 and the first to third clutches 41 to 43 and is in a drained state.

Next, when the driver sets the select lever to the D range, the spool 1 of the manual valve 111 is set.
11a moves one step to the left, and the first and second line pressure introduction ports 111b and 111c communicate with the first and second derivation ports 111d and 111e, respectively. For this reason, the line pressure is supplied to the control port 112e of the shift valve 112 to move the spool 112a to the right, so that the inlet port 112b and the first outlet port 112c communicate. Also, the second outlet port 112d communicates with the drain port, and the line pressure of the third clutch control line 116 remains drained. Further, the line pressure is applied to the first duty solenoid 10
2 and at the second clutch control line 106 to the second duty solenoid 107. In the low mode, only the first duty solenoid 102 operates as shown in FIG.
The first clutch 41 is supplied to the first clutch 41 via the second introduction port 112b, the first outlet port 112c, and the first clutch control line 101. As a result, the first clutch 41
Only in the engaged state, the engine output is transmitted to the transmission output shaft 28 via the toroidal transmission mechanism 1 and the planetary gear mechanism 2. In the high mode, only the second duty solenoid 107 operates as shown in FIG.
As a result, the line pressure is reduced to the second clutch control line 106.
Is supplied to the second clutch 42 via the As a result,
Only the second clutch 42 is engaged, and the engine output is transmitted through the transmission output shaft 2 via the toroidal transmission mechanism 1 only.
8 is transmitted.

On the other hand, when the driver sets the select lever to the R range, as shown in FIG. 15, the spool 111a of the manual valve 111 moves to the left by one more stage, and the second line pressure introduction port 111c and the second The communication state with the outlet port 111e is maintained, but the first line pressure introduction port 111b and the first outlet port 111d are in a non-communication state. Therefore, no line pressure is introduced into the control port 112e of the shift valve 112, and the spool 112a is shifted to the left side.
b communicates with the second outlet port 112d. The first outlet port 112c of the shift valve 112 communicates with the drain port, and the line pressure of the first clutch control line 101 is drained. Further, the manual valve 111
Of the first outlet port 111d communicates with the drain port,
For this reason, the line pressure of the second clutch control line 106 is also drained. Then, the first duty solenoid 1
02 is operated to reduce the line pressure to the inlet port 112b, the second outlet port 112d and the third
The third clutch 43 via the clutch control line 116
To supply. As a result, only the third clutch 43 is engaged, the carrier 23 of the planetary gear mechanism 2 is fixed to the housing 120, and the vehicle can move backward.

Therefore, in the second embodiment, the gear ratio of each of the gears 21, 22, 24 of the planetary gear mechanism 2 is set such that the maximum speed change point of the toroidal speed change mechanism 1 is the geared neutral point. 2 carrier 23
Since the third clutch 43 is provided as a brake for fixing the hydraulic control valve 60 so as not to rotate, the sleeve 62 of the hydraulic control valve 60 does not need to be provided with the restricting member 66 as in the first embodiment. Is moved to one end, the geared neutral state can be reliably set, and the speed change range can be widened. On the other hand, the carrier 23 of the planetary gear mechanism 2 is connected to the third clutch 4
3, the internal gear 24 (transmission output shaft 2)
8) rotates in the opposite direction to the forward direction, so that the vehicle can easily be set in the reverse state. Therefore, similarly to the first embodiment, it is possible to improve the fuel efficiency while achieving the fail-safe of the forward and backward traveling. Moreover, forward and reverse speed change control can be performed by one hydraulic control valve 60, and a regulating member is not required. Therefore, cost can be reduced as compared with the first embodiment.

In the second embodiment, the planetary gear mechanism 2
Is connected to the engine output shaft 5 via the toroidal transmission mechanism 1 and the internal gear 24 is connected to the transmission output shaft 28. Conversely, the internal gear 24 is connected to the engine output shaft 5. 5, the sun gear 21 may be connected to the transmission output shaft 28 via the toroidal transmission mechanism 1. However, the configuration as in the second embodiment is preferable because it can be transmitted to the transmission output shaft 28 in a state where the speed is reduced by the planetary gear mechanism 2.

In the first and second embodiments, the first and second hydraulic control valves 60 and 70 (the hydraulic control valve 60 in the second embodiment) are three-layer valves. If the feedback of (1) is performed separately, it is not necessary to use a three-layer valve.

[0083]

As described above, according to the toroidal type continuously variable transmission of the geared neutral start system of the present invention, the hydraulic control mechanism has a ratio range between the forward side in the low mode and the low side in the high mode. A first hydraulic pressure control valve having a restricting portion that regulates the control oil pressure so that the shift control can be performed only in the first mode, and the shift control can be performed only in a ratio range between the high side in the high mode and the reverse side in the low mode. Or a second hydraulic control valve having a restricting portion for restricting the control hydraulic pressure, or setting the gear ratio of each gear of the planetary gear mechanism so that the maximum shift point of the toroidal transmission mechanism is the geared neutral point. Then, by providing a brake that fixes the carrier of the planetary gear mechanism so that it does not rotate, while ensuring the geared neutral state and achieving fail-safe, Widely as possible the speed range can be improved of the fuel economy.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a schematic configuration of a toroidal-type continuously variable transmission according to a first embodiment of the present invention.

FIG. 2 is a hydraulic circuit diagram showing a hydraulic control mechanism.

FIG. 3 is a planetary speed diagram of a planetary gear mechanism.

FIG. 4 is a diagram corresponding to FIG. 2, showing a geared neutral state or a parking state.

FIG. 5 is a view corresponding to FIG. 2, showing a state on the forward side in a low mode.

FIG. 6 is a diagram corresponding to FIG. 2, showing a low-side state in a high mode.

FIG. 7 is a diagram corresponding to FIG. 2, showing a high-side state in a high mode.

FIG. 8 is a diagram corresponding to FIG. 2, showing a state of a reverse mode in a low mode.

FIG. 9 is a view corresponding to FIG. 1 showing the second embodiment.

FIG. 10 is a hydraulic circuit diagram illustrating a hydraulic control mechanism according to a second embodiment.

FIG. 11 is a planetary speed diagram of the planetary gear mechanism according to the second embodiment.

FIG. 12 is a diagram corresponding to FIG. 10, showing a geared neutral state or a parking state.

FIG. 13 is a view corresponding to FIG. 10 showing a state of a low mode.

FIG. 14 is a diagram corresponding to FIG. 10 showing a state of a high mode.

FIG. 15 is a view corresponding to FIG. 10, showing a state of reverse travel.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Toroidal transmission mechanism 2 Planetary gear mechanism 5 Engine output shaft 6 Input disk 7 Output disk 8 Power roller 21 Sun gear 22 Planetary gear 23 Carrier 24 Internal gear 28 Transmission output shaft 41 First clutch (pressure-operated clutch) 43 Third clutch (brake) 51 Hydraulic control mechanism 60 First hydraulic control valve 66 Regulatory member (Regulator) 70 Second hydraulic control valve 76 Regulatory member (Regulator) 101 First clutch control line (Clutch control) Route)

Claims (5)

[Claims] 1. A toroidal transmission having an input disk connected to an engine output shaft, an output disk opposed to the input disk, and a power roller that is frictionally contacted between the input and output disks in a tiltable manner. A hydraulic control mechanism for controlling the speed ratio of the toroidal transmission mechanism by driving the power roller of the toroidal transmission mechanism to a predetermined inclined position; a sun gear; and a revolving gear around the sun gear meshing with the sun gear. A planetary gear, a carrier that supports the planetary gear and rotates with the revolution of the planetary gear, and an internal gear that meshes with the planetary gear. Two of the sun gear, the carrier, and the internal gear The components are connected to the engine output shaft via the toroidal transmission mechanism and without the toroidal transmission mechanism, respectively. A planetary gear mechanism connected to the transmission output shaft. In low mode, engine output is transmitted to the transmission output shaft via the toroidal transmission mechanism and the planetary gear mechanism. Is transmitted to the transmission output shaft only through the toroidal transmission mechanism, and controls the speed ratio of the toroidal transmission mechanism in the low mode to achieve forward, reverse, and geared neutral states. A toroidal-type continuously variable transmission with a neutral start system, wherein the hydraulic control mechanism regulates a control oil pressure so that gear shift control can be performed only in a ratio range between a forward side in a low mode and a low side in a high mode. A first hydraulic control valve having a restricting portion to be operated, and only in a ratio range between a high side in a high mode and a reverse side in a low mode. Toroidal type continuously variable transmission, characterized in that a second hydraulic control valve having a regulating portion for regulating the control oil pressure to be performed fast control. 2. The toroidal continuously variable transmission according to claim 1, wherein each of the first and second hydraulic control valves comprises a three-layer valve. 3. The toroidal-type continuously variable transmission according to claim 2, wherein the engine output shaft and a component connected to the engine output shaft without passing through the toroidal transmission mechanism in the planetary gear mechanism are pressure-operated. The hydraulic control path of the toroidal transmission mechanism is switched from the first hydraulic control valve to the second hydraulic control valve when switching from the low side to the high side in the high mode. A toroidal-type continuously variable transmission, wherein the operating pressure in the control path of the clutch is drained. 4. The toroidal-type continuously variable transmission according to claim 2, wherein the engine output shaft and a component connected to the engine output shaft without passing through the toroidal transmission mechanism in the planetary gear mechanism are pressure-operated. And when the reverse is selected during forward travel, the operating pressure in the control path of the clutch is drained until the vehicle speed during forward travel falls below a predetermined value. A toroidal-type continuously variable transmission characterized by the following. 5. A toroidal transmission having an input disk connected to an engine output shaft, an output disk opposed to the input disk, and a power roller that is frictionally contacted between the input and output disks in a tiltable manner. A hydraulic control mechanism for controlling the speed ratio of the toroidal transmission mechanism by driving the power roller of the toroidal transmission mechanism to a predetermined inclined position; a sun gear; and a revolving gear around the sun gear meshing with the sun gear. A planetary gear, a carrier that supports the planetary gear and rotates with the revolution of the planetary gear, and an internal gear that meshes with the planetary gear, wherein one of the sun gear and the internal gear is the engine output shaft. And the other is connected to the transmission output shaft via the toroidal transmission mechanism, and the carrier is connected to the engine output shaft. A planetary gear mechanism that is connected without passing through the toroidal transmission mechanism.In low mode, engine output is transmitted to the transmission output shaft via the toroidal transmission mechanism and the planetary gear mechanism, while in high mode. Transmitting the engine output to the transmission output shaft via only the toroidal transmission mechanism, and controlling a gear ratio of the toroidal transmission mechanism in the low mode to achieve a geared neutral state. A start-type toroidal-type continuously variable transmission, wherein a gear ratio of each gear of the planetary gear mechanism is set such that a maximum shift point of the toroidal transmission mechanism is a geared neutral point, and a carrier of the planetary gear mechanism. Characterized in that it has a brake for fixing the wheel so that it does not rotate Continuously variable transmission.