JP2003004113A - Toroidal type continuously variable transmission with hydraulic thrusting mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To sufficiently maintain thrust between a disc and a power roller by surely preventing leakage from an oil pressure chamber even in the case of the elastic deformation of an input disc. SOLUTION: Two-stage outer periphery side seal portions 40, 42 separated from each other in the axial direction are provided between the inner periphery face of a peripheral wall 21a of a hydraulic cylinder 21 and the outer periphery of a first input disc 2a. The outer periphery side seal portions 40, 42 are constructed by forming two-streak circular grooves in the inner periphery face of the peripheral wall 21a and mounting seal members such as O-rings in the circular grooves. An inner periphery side seal portion 44 is provided between a fitting cylinder 26 of the hydraulic cylinder 21 and the inner periphery of the first input disc 2a. The inner periphery side seal portion 44 is constructed by forming a one-streak circular groove in the outer periphery face of the fitting cylinder 26 and mounting a seal member such as an O-ring in the circular groove.

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 equipped with a hydraulic pressing mechanism used as a transmission mechanism for automobiles and the like.

[0002]

2. Description of the Related Art FIG. 4 shows a double-cavity half-toroidal type continuously variable transmission using a hydraulic pressing mechanism.

In this toroidal type continuously variable transmission, a first input disk 2a and an output disk 3a which form a first cavity 1a in a housing 1 and a second input disk 2b which forms a second cavity 1b. And an output disc 3b. First input / output disk 2a, 3a
A pair of power rollers 5 is provided between them. The outer peripheral surface of the power roller 5 is in contact with the traction surface 4 of each of the disks 2a and 3a. The second input / output disk 2b,
A pair of power rollers 5 is also provided between 3b, and is in contact with the traction surface 4 thereof.

These power rollers 5 are rotatably attached to the trunnions 7 by power roller bearings 6. Each trunnion 7 is swingable about a trunnion shaft 8.

The traction surface 4 of each disk 2a, 2b, 3a, 3b has a concave shape obtained by rotating an arc centered on the trunnion shaft 8 about an axis perpendicular to the trunnion shaft 8. The first input disk 2a is attached to the input shaft 10 so as to be relatively movable in the axial direction of the input shaft 10 in a state in which the first ball spline 11 is used to prevent rotation.

The second input disk 2b is attached to the input shaft 10 so as to be relatively movable in the axial direction of the input shaft 10 in a state where the second ball spline 12 prevents rotation of the input shaft 10. Therefore, the input disks 2a,
2b rotates integrally with the input shaft 10. This input shaft 10
Is rotationally driven by a drive source such as an engine. The output disks 3a and 3b are provided between the input disks 2a and 2b. The first output disc 3a faces the first input disc 2a and the second output disc 3b is the second.
Facing the input disk 2b.

The output disks 3a and 3b are supported on the input shaft 10 through bearings 13 and 14 so as to be rotatable relative to each other. The output disks 3a and 3b are connected to the connecting member 1
They are connected by 5 and rotate in synchronization with each other. An output gear 16 is provided on the connecting member 15.

A hydraulic loading mechanism 20 is provided on the back side of the first input disk 2a. The loading mechanism 20 includes a hydraulic cylinder 21 attached to the input shaft 10 so as to face the back surface of the input disc 2a, and a peripheral wall 21a of the hydraulic cylinder 21 is provided on the outer periphery of the input disc 2a via a seal member 22. This hydraulic cylinder 2 is fitted liquid-tightly and slidably in the axial direction.
A hydraulic chamber 25 having a hermetically sealed structure is formed between 1 and the input disk 2a.

The hydraulic cylinder 21 integrally has a fitting cylinder 26 at the center thereof, and the input shaft 10 is fitted in the fitting cylinder 26. Then, an oil supply passage 27 that communicates from the inner hole 10a of the input shaft 10 to the hydraulic chamber 25 in the hydraulic cylinder 21 is formed,
The control valve 2 is controlled by the hydraulic pump 28 through the oil supply passage 27.
Oil is fed under pressure into the hydraulic chamber 25 via 9. A disc spring 30 is provided in the hydraulic chamber 25 as a preload applying means.

When the input shaft 10 and the input disks 2a, 2b rotate in conjunction with a drive source such as an engine, the hydraulic pump 28 passes through the control valve 29 and the hydraulic chamber 25.
Oil is supplied into the first input disk 2a by the oil pressure.
Is pressed toward the first output disk 3a, and the reaction force received by the hydraulic cylinder 21 is applied to the input shaft 10, so that the second input disk 2b becomes the second output disk 3b.
Is pressed toward. The power of rotation of the input disks 2a, 2b is transmitted via the power roller 5 to the output disks 3a, 3b.
b, and the output gear 16 rotates in conjunction with the output disks 3a and 3b.

When changing the rotation speed ratio between the input shaft 10 and the output gear 16, each power roller 5 is swung about the trunnion shaft 8. By this swing, the power roller 5 and the peripheral surface of each power roller 5 are swung. The contact position of the disks 2a, 2b, 3a, 3b with the traction surface 4 is changed, whereby the rotation speed ratio between the input disks 2a, 2b and the output disks 3a, 3b, that is, the rotation of the input shaft 10 and the output gear 16. The speed ratio changes.

[0012]

By the way, in the state shown in FIG. 4, the power roller 5 is swung so that the rotational torque is transmitted from the input shaft 10 to the output gear 16 in an increased state. The power roller 5 comes into contact with the traction surface 4a of the first input disk 2a at two points (positions indicated by A and B in FIG. 4) on the outer peripheral side thereof to generate a pressing force. Thus, when a pressing force is generated at two points on the outer peripheral side of the traction surface 4a, as shown in FIG. 5, the outer peripheral shape of the first input disc 2a, which was a perfect circle, is the first input disc 2a itself. It becomes an elliptical shape due to elastic deformation of.
At this time, the inner peripheral shape of the first input disk 2a, which was a perfect circle, also becomes an elliptical shape, although the deformation amount is not as great as the outer peripheral shape.

When the first input disk 2a is elastically deformed in this way, a large gap C1 is generated between the outer circumference of the first input disk 2a and the inner circumference of the peripheral wall 21a of the hydraulic cylinder 21, and the first input disk 2a is generated. A gap C2 may be generated between the inner circumference of the disk 2a and the outer circumference of the fitting cylinder 26, and the oil in the hydraulic chamber 25 may leak to the outside. When the oil in the hydraulic chamber 25 leaks, the pressing force from the first input disk 2a to the first output disk 3a and the pressing force from the second input disk 2b to the second output disk 3b are reduced, The peripheral surface of the power roller 5 and each disk 2a, 2b, 3
Slip may occur between the a and 3b traction surfaces 4 and normal torque transmission may become impossible.

Here, it is conceivable to increase the hydraulic pressure supplied from the hydraulic pump 28, but doing so is not preferable because the load on the hydraulic pump 28 increases and the fuel consumption deteriorates.

The present invention has been made in view of the above circumstances, and reliably prevents the hydraulic chamber from leaking even when the input disc is elastically deformed and ensures a sufficient pressing force between the disc and the power roller. An object of the present invention is to provide a toroidal type continuously variable transmission equipped with a hydraulic pressing mechanism capable of achieving the above.

[0016]

In order to achieve the above object, the invention according to claim 1 comprises an input disk and an output disk which are coaxially arranged to face each other, and the input disk and the output disk. An oscillating power roller provided between the input disk and the rear surface side of the input disk is pressed against the output disk to output the rotational power of the input disk through the power roller. In a toroidal type continuously variable transmission including a hydraulic pressing mechanism for transmitting to a disc, the hydraulic pressing mechanism is disposed on the back side of the input disc and forms a hydraulic chamber between the hydraulic cylinder and the input disc. And an oil supply means for supplying oil into the hydraulic chamber to press the input disc, and at the inner peripheral side of the hydraulic cylinder and the input disc. The inner peripheral side sealing portion provided in the moving parts,
At least two stages of outer peripheral seal portions axially separated from each other are provided on outer peripheral sliding portions of the hydraulic cylinder and the input disk.

According to the present invention, even if a pressing force is generated on the outer peripheral side of the input disk due to the contact with the power roller, and a large gap is generated between the outer peripheral side of the input disk and the hydraulic cylinder, the outer peripheral side of the two stages. The seal portion closes the gap to prevent oil in the hydraulic chamber from leaking to the outside. Further, the gap generated between the inner circumference of the input disk and the inner circumference of the hydraulic cylinder prevents the oil in the hydraulic chamber from leaking to the outside due to the inner seal portion closing the gap.

According to a second aspect of the present invention, an input disk and an output disk are arranged coaxially opposite to each other, and a swingable power roller provided between the input disk and the output disk. And a hydraulic pressing mechanism that is disposed on the back side of the input disc and that pushes the input disc toward the output disc to transmit the rotational power of the input disc to the output disc via the power roller. In the continuously variable transmission, the hydraulic pressure mechanism is provided on the back side of the input disc to form a hydraulic chamber between the hydraulic cylinder and the input disc; An oil supply means for pressing the disc, and an inner peripheral side seal part is provided on the inner peripheral side sliding part of the hydraulic cylinder and the input disc. The sliding portion of the cylinder and the outer peripheral side of the input disc, provided with an outer peripheral side sealing portion of the first stage having an increased axial dimension as compared to the inner peripheral side sealing portion.

According to the present invention, even if a pressing force is generated on the outer peripheral side of the input disk due to contact with the power roller and a large gap is generated between the outer peripheral surface of the input disk and the hydraulic cylinder, the axial dimension is reduced. The enlarged one-stage outer peripheral seal portion prevents the oil in the hydraulic chamber from leaking to the outside by closing the gap. Further, the gap generated between the inner circumference of the input disk and the inner circumference of the hydraulic cylinder prevents the oil in the hydraulic chamber from leaking to the outside due to the inner seal portion closing the gap.

Furthermore, the invention according to claim 3 is the same as claim 1.
In a toroidal type continuously variable transmission including the hydraulic pressing mechanism described above, the outer peripheral seal portion is provided with an annular groove formed on an outer peripheral surface of the input disk, and an inner peripheral surface of the hydraulic cylinder mounted in the annular groove. And a seal member that abuts the surface.

According to the present invention, the centrifugal force when the input disk rotates acts on the seal member, and the seal member comes into close contact with the inner peripheral surface of the hydraulic cylinder, so that the liquid tightness of the outer peripheral seal portion is further improved. .

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. The same components as those shown in FIGS. 4 and 5 are designated by the same reference numerals, and the description thereof will be omitted. FIG. 1 shows a hydraulic loading mechanism 20 of the first embodiment provided on the back side of the first input disk 2a.

The loading mechanism 20 of this embodiment has two axially spaced portions (2) between the inner peripheral surface of the peripheral wall 21a of the hydraulic cylinder 21 and the outer periphery of the first input disk 2a.
Outer peripheral side seal portions 40 and 42 are provided. The outer peripheral side seal portions 40 and 42 are configured by forming two annular grooves on the inner peripheral surface of the peripheral wall 21a and mounting a seal member such as an O-ring in the annular grooves.

Also between the fitting cylinder 26 of the hydraulic cylinder 21 and the inner circumference of the first input disc 2a, the inner circumference side seal portion 44 is formed.
Is provided. The inner peripheral side seal portion 44 is configured by forming a single annular groove on the outer peripheral surface of the fitting cylinder 26 and mounting a seal member such as an O-ring in the annular groove.

According to the above configuration, the first input disk 2
The power roller 5 comes into contact with two points on the outer peripheral side of the traction surface 4a of a to generate a pressing force, and as shown in FIG.
The first input disk 2a is elastically deformed, and a large gap C1 is generated between the outer circumference of the first input disk 2a and the inner circumference of the peripheral wall 21a of the hydraulic cylinder 21. Even if a gap C2 is generated between the outer periphery of the fitting cylinder 26, the large gap C1 is set to the outer peripheral side seal portion 4 of two stages.
The oil in the hydraulic chamber 25 is prevented from leaking to the outside by blocking with 0, 42. More specifically, the gap C1 has different sizes on the back surface side of the first input disk 2a and the traction surface 4a side, but of the two outer peripheral side seal portions 40, 42 located on the smaller gap side. One reliably prevents the oil from leaking from the hydraulic chamber 25 to the outside.

The inner circumference of the first input disk 2a and the fitting cylinder 2
The gap C2 generated between the outer periphery of the inner peripheral side 6 and the outer periphery of the inner peripheral side 6 prevents the oil in the hydraulic chamber 25 from leaking to the outside due to the inner peripheral side seal portion 44 being closed. Therefore, even if the first input disk 2a is elastically deformed, the leaks in the hydraulic chamber 25 are reliably prevented by the two-stage outer peripheral side seal portions 40, 42 and the inner peripheral side seal portion 44, and
A sufficient pressing force between the input disk 2a and the power roller 5 can be secured.

FIG. 2 shows a hydraulic loading mechanism 20 of the second embodiment. In the loading mechanism 20 of the present embodiment, the outer peripheral seal portion 46, which has a longer axial dimension than the inner peripheral seal portion 44, is formed between the inner peripheral surface of the peripheral wall 21a of the hydraulic cylinder 21 and the outer periphery of the first input disk 2a. It is provided in between. The outer peripheral side seal portion 46 is provided on the peripheral wall 2.
One annular groove having a long groove width is formed on the inner peripheral surface of 1a, and a sealing member such as a wide O-ring is mounted in the annular groove.

According to the above construction, as shown in FIG. 5, the first input disk 2a is elastically deformed and a large gap is formed between the outer circumference of the first input disk 2a and the inner circumference of the peripheral wall 21a of the hydraulic cylinder 21. C1 occurs and the first input disk 2
Even if a gap C2 is generated between the inner periphery of a and the outer periphery of the fitting cylinder 26, the large gap C1 is closed by the outer peripheral seal portion 46 having a long axial dimension and the oil in the hydraulic chamber 25 is closed. Is prevented from leaking to the outside, and the clearance C2 prevents the oil in the hydraulic chamber 25 from leaking to the outside due to the inner peripheral side seal portion 44 being closed.

Therefore, even if the first input disk 2a is elastically deformed, the outer peripheral side seal portion 46 and the inner peripheral side seal portion 44 surely prevent the hydraulic chamber 25 from leaking, and the first input disk 2a and the power source are protected. A sufficient pressing force between the rollers 5 can be secured.

FIG. 3 shows a hydraulic loading mechanism 20 of the third embodiment. The loading mechanism 20 of the present embodiment has the structure of the two-stage outer peripheral side seal portions 48 and 50 provided between the inner peripheral surface of the peripheral wall 21a of the hydraulic cylinder 21 and the outer periphery of the first input disk 2a. The input disk 2a is formed with two annular grooves on the outer peripheral surface thereof, and a seal member such as an O-ring is mounted in these annular grooves.

According to the above construction, as shown in FIG. 5, the first input disk 2a is elastically deformed and a large gap is formed between the outer circumference of the first input disk 2a and the inner circumference of the peripheral wall 21a of the hydraulic cylinder 21. C1 occurs and the first input disk 2
Even if a gap C2 is generated between the inner periphery of a and the outer periphery of the fitting cylinder 26, the large gap C1 is set to the outer peripheral side seal portion 4 of two stages.
8 and 50 are closed to prevent the oil in the hydraulic chamber 25 from leaking to the outside, and the clearance C2 prevents the oil in the hydraulic chamber 25 from leaking to the outside by closing the inner peripheral seal portion 44. .

Further, in this embodiment, since the seal member is mounted in the annular groove formed on the outer peripheral surface of the first input disk 2a, the centrifugal force when the first input disk 2a rotates is the seal member. The sealing member is brought into close contact with the inner peripheral surface of the peripheral wall 21a of the hydraulic cylinder 21. This allows
The liquid tightness of the outer peripheral side seal portions 48, 50 is improved.

Therefore, even if the first input disk 2a is elastically deformed, the outer peripheral seal portions 48, 50 and the inner peripheral seal portion 44 reliably prevent the hydraulic chamber 25 from leaking, and the first input disk 2a is prevented. And, the pressing force between the power rollers 5 can be sufficiently secured.

In the first to third embodiments described above,
Although the description has been given of the one-stage inner peripheral side seal portion 44, the gist of the present invention is not limited to this, and when two stages of the inner peripheral side seal portion axially separated are provided, the hydraulic chamber 25 is further provided.
It is possible to surely prevent the leakage.

[0035]

According to the toroidal type continuously variable transmission equipped with the hydraulic pressing mechanism of the present invention, even if the input disk is elastically deformed, leakage of the hydraulic chamber can be reliably prevented and the pressing force between the disk and the power roller can be reduced. You can secure enough.

[Brief description of drawings]

FIG. 1 is a diagram showing a hydraulic loading mechanism of a first embodiment provided on the back side of an input disc.

FIG. 2 is a diagram showing a hydraulic loading mechanism of a second embodiment provided on the back side of an input disc.

FIG. 3 is a diagram showing a hydraulic loading mechanism of a third embodiment provided on the back side of an input disc.

FIG. 4 is a diagram showing a double-cavity half-toroidal type continuously variable transmission using a hydraulic pressing mechanism.

FIG. 5 is a schematic view showing a state in which an input disk is elastically deformed by contact with a power roller.

[Explanation of symbols]

2a First input disc (input disc) 3a First output disc (output disc) 5 power rollers 20 Loading mechanism (hydraulic pressure mechanism) 25 hydraulic chamber 21 hydraulic cylinder 21a Perimeter wall 26 Fitting tube 44 Inner peripheral side seal part 40, 42, 46, 48, 50 Outer peripheral side seal part 28 hydraulic pump 29 Control valve

Claims (3)

[Claims] 1. An input disk and an output disk which are coaxially arranged opposite to each other, a swingable power roller provided between the input disk and the output disk, and a back side of the input disk. A toroidal type continuously variable transmission that is provided with a hydraulic pressing mechanism that presses the input disk toward the output disk to transmit the rotational power of the input disk to the output disk via the power roller, The hydraulic pressing mechanism includes a hydraulic cylinder arranged on the back side of the input disc to form a hydraulic chamber between the input disc and oil supply means for supplying oil into the hydraulic chamber to press the input disc. And an inner peripheral side seal portion is provided on an inner peripheral side sliding portion of the hydraulic cylinder and the input disk, and the hydraulic cylinder and the input disc are provided. The sliding portion of the outer peripheral side of the click, at least axially spaced 2
A toroidal type continuously variable transmission equipped with a hydraulic pressing mechanism, which is provided with a seal portion on the outer peripheral side of the step. 2. An input disk and an output disk arranged coaxially opposite to each other, a swingable power roller provided between the input disk and the output disk, and a back side of the input disk. A toroidal type continuously variable transmission that is provided with a hydraulic pressing mechanism that presses the input disk toward the output disk to transmit the rotational power of the input disk to the output disk via the power roller, The hydraulic pressing mechanism includes a hydraulic cylinder arranged on the back side of the input disc to form a hydraulic chamber between the input disc and oil supply means for supplying oil into the hydraulic chamber to press the input disc. And an inner peripheral side seal portion is provided on an inner peripheral side sliding portion of the hydraulic cylinder and the input disk, and the hydraulic cylinder and the input disc are provided. A toroidal type equipped with a hydraulic pressing mechanism, characterized in that a one-step outer peripheral seal part whose axial dimension is larger than that of the inner peripheral seal part is provided on the outer peripheral slide part Continuously variable transmission. 3. The outer peripheral seal portion is composed of an annular groove formed on the outer peripheral surface of the input disk, and a seal member mounted in the annular groove and abutting on the inner peripheral surface of the hydraulic cylinder. A toroidal type continuously variable transmission equipped with the hydraulic pressing mechanism according to claim 1.