JP2001254795A - Toroidal type continuously variable transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the durability of a race face etc., of a disk by preventing a roller from becoming high temperature in a toroidal type continuously variable transmission. SOLUTION: Lubricating oil is spread from first and second pipes 32 and 33 extending to positions near torque transmission ranges T1 and T2 of the circumferential face 17b of the roller 17 toward the torque transmission ranges T1 and T2. This method can effectively lubricate and cool them in a small amount of the lubricating oil. The pipes 32 and 33 are formed into arc and one ends are supported by a carriage 18. The lubricating oil is guided to the respective pipes 32 and 33 via channels 36, 37, and 38 in the carriage 18.

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 in which rollers are disposed over a toroidal gap formed between an input disk and an output disk.

[0002]

2. Description of the Related Art In this type of toroidal type continuously variable transmission,
As shown in JP-A-6-502476, a plurality of groups of rollers whose positions are variable are partially toroidally formed on opposing surfaces of input and output coaxial disks rotating in opposite directions. Transfer traction between corresponding track surfaces. The input disk and the output disk have a center hole through which the input shaft connected to the power source is inserted, and the input disk is connected to the input shaft so as to be integrally rotatable, and the output disk rotates on the input shaft. It is freely supported.

The rotation speed transmitted from the input disk to the output disk changes as the position of the roller changes. That is, if the roller contacts the input disc at a relatively high radius and contacts the output disc at a relatively low radius, the output disc rotates faster than the input disc and the variator is high. The gear ratio is set. On the other hand, if the roller contacts the input disk at a relatively low radius and contacts the output disk at a relatively high radius, the output disk rotates slower than the input disk and the variator is low. The gear ratio is set.

[0004] Usually, the roller is rotatably supported by a carriage extending in a direction perpendicular to its support shaft.
The axis of the carriage is inclined at a predetermined caster angle with respect to a plane including the center circle of the torus.
The input disk and the output disk are urged in a direction approaching each other by a hydraulic cylinder, and the rollers are also urged in a direction pressed against the track surface of the disk by the hydraulic cylinder via a carriage that supports the rollers. Have been. By controlling the hydraulic pressure generated by these hydraulic cylinders, a force that balances the torque transmitting force received by the roller is provided to the roller via the carriage. This allows
The roller angle is changed so that the torque of the output disk is balanced with the torque of the input disk, and an appropriate torque ratio is maintained.

In practice, there are inherent torque loads on the rollers for various combinations of various essential parameters (eg, operator requirements, engine load, engine speed, final output speed, etc.), and the control system Receives the input representing all the essential parameters and sets the appropriate hydraulic pressure in the hydraulic cylinder that matches the torque reaction force received by the rollers when the torque ratio between the input disk and the output disk is properly maintained. I have.

[0006] In the above description, it has been described that the rollers contact the respective discs for transmitting the torque, but actually, they do not. Then, how to transmit the torque,
The lubricating oil interposed between the roller and the disc plays a role of transmitting power in addition to the usual role of lubricating and cooling to prevent wear of both. That is, in the related art, as shown in FIGS. 8A and 8B, a passage 9 penetrating through the carriage 90 along the direction in which the carriage 90 extends.
1 along a direction in which the carriage 90 extends, a supply zone 94 where the peripheral surface 93 intersects the carriage 90 in a side view with respect to the peripheral surface 93 which is the rolling surface of the roller 92.
, The lubricating oil is supplied by directly injecting the lubricating oil.

[0007] The lubricating oil supplied to the peripheral surface 93 of the roller 92 in the supply zone 94 is transmitted to the torque transmitting area of the peripheral surface 93 of the roller 92 when the roller 92 rotates 1/4 or 3/4. Reaches 95 and 96 and performs the functions of lubrication, cooling and power transmission.

[0008]

However, since the distance from the supply zone 94 to the torque transmission areas 95 and 96 is long, the lubricating oil is required to reach the lubrication required zones 95 and 96 due to the centrifugal force of the roller 92 and other influences. Is scattered, and the amount of lubricating oil that can reach the torque transmission areas 95 and 96 decreases. For this reason, lubrication and cooling become insufficient, the temperature of the roller rises due to frictional heat, and the evaporation of lubricating oil on the raceway surface is promoted, resulting in abnormalities such as separation of the raceway surface.
In addition, the torque transmission ability also decreases.

By the way, there is a demand to reduce the size and weight of the toroidal type continuously variable transmission mounted on the vehicle as much as possible. Therefore, each disk and each roller must be reduced in size. However, if the required torque is transmitted under such conditions, the contact pressure between the disk and the roller increases. In particular, when the surface area of the roller is reduced due to miniaturization, heat dissipation is deteriorated, so that the temperature of the roller is increased to accelerate the deterioration of the lubricating oil, and as a result, there is a possibility that the raceway surface may peel.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to prevent the roller from becoming hot and prevent the raceway surface from peeling off, thereby improving the durability. It is to provide.

[0011]

Means for Solving the Problems and Effects of the Invention As a means for solving the above-mentioned object, the invention according to claim 1 is a toroid formed between an input disk and an output disk. A toroidal-type continuously variable transmission in which rollers are disposed across a gap between the rollers, wherein a means for spraying lubricant to the rollers or the disks from a position near the torque transmission region between the rollers and the disks is provided. It is assumed that.

In this configuration, since lubricating oil can be supplied from a position near the torque transmitting region between the roller and the disk to the roller or the disk in the torque transmitting region, effective lubrication can be achieved with a relatively small amount of lubricating oil. I can do it. As a result, generation of frictional heat can be suppressed, and durability can be improved. Further, the torque transmission ability can be maintained high. This can substantially contribute to the reduction in size and weight of the continuously variable transmission. The region where the lubricating oil is sprayed may be the torque transmission region, or may be the region of the roller or the disk immediately before reaching the torque transmission region (the region on the upstream side in the rotation direction).

According to a second aspect of the present invention, in the first aspect, the spraying means includes a pipe supported by a carriage rotatably supporting a roller and extending to a position near a torque transmission area. It is. By using the pipe having this configuration, it is possible to supply the lubricating oil to the vicinity of the portion where the roller and the disk come into contact with each other by using the conventional configuration that provides a path for circulating the lubricating oil in the carriage. Substantially possible.

According to a third aspect of the present invention, there is provided a toroidal-type continuously variable transmission in which rollers are disposed across a toroidal gap formed between an input disk and an output disk. It is characterized in that a recess or a through hole is provided. In this configuration, since the surface area of the roller can be increased by providing the concave portion or the through hole, the heat radiation of the roller can be improved and the temperature rise can be suppressed. As a result, the consumption and evaporation of the lubricating oil can be prevented, and the durability of the raceway surface and the like can be improved.

According to a fourth aspect of the present invention, there is provided a toroidal-type continuously variable transmission in which rollers are disposed across a toroidal gap formed between an input disk and an output disk. A passage through which the lubricating oil passes through the rotating shaft that passes through the output disc coaxially, and a lubricating oil spray port that is provided on the peripheral surface of the rotating shaft and sprays the lubricating oil from the passage is provided. Is what you do. In this configuration, the centrifugal force of the rotation of the rotating shaft can be used to effectively supply the lubricating oil to the rollers arranged around the rotating shaft, and lubrication,
The effect of cooling can be enhanced.

According to a fifth aspect of the present invention, there is provided a toroidal-type continuously variable transmission in which rollers are disposed across a toroidal gap formed between an input disk and an output disk. A large number of grooves for retaining an oil film are formed on at least one of the surface and the peripheral surface of the roller. In this configuration, since the oil film can be held on the raceway surface or the rolling surface of the roller, the lubrication effect and the cooling effect can be enhanced, and the durability can be improved.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic sectional view of a toroidal type continuously variable transmission according to an embodiment of the present invention. Referring to FIG. 1, a variator 1 of the continuously variable transmission A includes an input shaft 3 driven by a power source 2 of a vehicle, and a spline for connecting to the power source 2 is provided at one end of the input shaft 3. 4
Are formed. The input shaft 3 supports input disks 5, 6 near both ends thereof. These input disks 5,
6 is coupled to the input shaft 3 using the key 7 so that
The rotation of the input disks 5, 6 with respect to the input shaft 3 is prevented. Because of the key combination, relative axial movement in a limited range is allowed between the input shaft 3 and the input disks 5 and 6. This is because a required “terminal load” is applied to the variator 1 by urging the input disk 6 toward the other input disk 5 by a hydraulic cylinder 9 connected to an appropriate hydraulic power source 8. Note that spline connection may be used instead of key connection.

A variator 1 is provided at the axial center of the input shaft 3.
The annular output disk 10 constituting the output section of the rolling bearing 1
1 and rotatably supported. This output disk 1
0 are formed on both side surfaces with a partially toroidal raceway surface 12. Gear teeth 1 are provided on the outer peripheral surface of the output disc 10.
The output shaft 16 is provided in parallel with the input shaft 3 and is provided with a gear 14 having gear teeth meshing with the gear teeth 13 so as to be integrally rotatable. A gear transmission mechanism B for transmitting torque from the output disk 10 to the output shaft 16 is constituted by the gear teeth 13 and the gear 14. The rotation of the output shaft 16 is transmitted to driving wheels of the vehicle.

A gap S between the orbital surfaces 12 of the output disk 10 and the corresponding input disks 5 and 6 is partially formed in a toroidal gap S, and is partially toroidal on the input disks 5 and 6. The traction force is transmitted between a plurality of rollers 17 between a raceway surface 15 of the output disk 10 and a partially toroidal raceway surface 12 on the output disk 10. The roller 17 is supported by a carriage 18 so as to be rotatable around a rotation axis K. Several sets of rollers / carriages are interposed between the input disc 5 and the output disc 10, but only one set is shown in FIG. Input disk 6
Similarly, only one set is shown between the power disk 10 and the output disk 10. In practice, it is usual that a set of three rollers is provided between a set of disks, and these three rollers are arranged on a circle around the center axis C of the input shaft 3. Placed at intervals. The positions of the six rollers are all controlled by a common hydraulic control device so that the same transmission ratio is always transmitted during operation.

The center 19 of each roller 17 is aligned with the raceway surface 12,1.
The five common toruses are set to lie on the imaginary center circle 20, but in operation, they can move a limited range back and forth along this circle. The hydraulic circuit 21 includes a hydraulic cylinder 22 and a roller 1 via the carriage 18.
7 is controlled. Next, referring to FIG. 2A, the carriage 18 is fixed to a first portion 25 to which a rolling bearing 24 that rotatably supports the support shaft 23 of the roller 17 is attached, and to the first portion 25. A second portion 26 in the form of a hollow link shaft. Although not shown, the second portion 26 is connected to a piston movable in the hydraulic cylinder. The hydraulic cylinder controls the force exerted on the roller by the piston, and this force balances the torque reaction force applied to the roller.

Referring to FIG. 2B, the carriage 18 has a pair of side plates 27 and 28 opposed to each other with a predetermined gap provided between a pair of side surfaces 17a of the roller 17, and a circumferential surface which is a rolling surface of the roller 17. It has a U-shaped cross section having a connecting portion 29 that opposes a part of the surface 17b with a predetermined gap and connects the base ends 30 of the side plates 27 and 28.
2A, a pair of regions where the peripheral surface 17b of the roller 17 intersects with the carriage 18 [hidden by the base end 30 and the end 31 of the side plate 27 in side view of FIG. The area rotated by 1/4 turn (90 degrees) from the area where the roller 17 is rotated becomes the torque transmission areas T1 and T2, respectively. become.

Then, from the base end portion 30 of the side plate 27, a 1/4 turn is made concentrically with the peripheral surface 17b of the roller 17 in the rotation direction (clockwise direction in the figure), and the torque transmission region T1
And a torque transmission area that makes a quarter turn in a rotational direction (clockwise direction in the figure) from the distal end portion 31 of the side plate 27 along the peripheral surface 17b of the roller 17 from the first pipe 32 extending to a position close to. A second pipe 33 extending to T2 is provided. Spray ports (not shown) are formed at the tips 34, 35 of the pipes 32, 33, and spray lubricating oil toward the torque transmission areas T1, T2.

The lubricating oil is guided to the first pipe 32 by the pressure pump P through a passage 36 passing through the second portion 26 and a passage 37 in the connecting portion 29 of the first portion 25. On the other hand, a passage 38 extending in the longitudinal direction of the side plate 27 branches off from the middle of the passage 37 in the connecting portion 29, and lubricating oil is guided to the second pipe 33 via the passage 38.
According to the present embodiment, the roller 17 and each of the disks 5, 6, 1
The lubricating oil is sprayed from the positions near the torque transmission regions T1 and T2 to 0 and toward the torque transmission regions T1 and T2 on the peripheral surface 17b of the roller 17, so that the effect is obtained with a relatively small amount of lubrication oil. Effective lubrication. As a result, since the generation of frictional heat can be suppressed, the occurrence of peeling of the raceway surfaces 12, 15 can be prevented, and the durability can be improved. Further, the torque transmission ability can be maintained high. As a result, it can substantially contribute to the reduction in size and weight of the continuously variable transmission.

Incidentally, in the embodiment of FIG.
The lengths of the pipes 32 and 33 may be slightly shortened so that lubricating oil may be sprayed on the peripheral surface 17b of the roller 17 immediately upstream of the torque transmission regions T1 and T2. Next, FIGS. 3A and 3B show another embodiment of the present invention. FIG.
As shown in FIGS. 2A and 2B, the present embodiment is different from FIG.
The main difference from the first embodiment is that the first and second pipes 39, extending parallel to the side surface 17a of the roller 17 from the longitudinal central portion of the side plate 27 to positions near the torque transmission zones T1, T2, respectively. 40 is provided.

The first and second pipes 39 and 40 are passed through a passage 36 in the second portion 26, a passage 41 in the side plate 27, and separate passages 42 and 43 branched from the passage 41, respectively. Lubricating oil is supplied. Also in the present embodiment,
The same operation and effect as the embodiment of FIGS. 2A and 2B can be obtained. Also, the pipes 39 and 40 can be shortened,
The size can be reduced. 4A and 4B show still another embodiment of the present invention. In the embodiment of FIG. 4A, the side surface 17a of the roller 17 is provided.
Is provided with a through hole 44 composed of a plurality of circular holes. The through holes 44 are arranged at equal intervals on a circumference around the rotation axis 45 of the roller 17.

According to the present embodiment, since the surface area of the roller 17 can be increased by providing the through-hole 44, the heat radiation of the roller 17 can be improved.
The temperature of the roller 17 can be prevented from rising. Therefore, even if each of the discs 5, 6, and 10 and the roller 17 are miniaturized, there is no possibility that the raceway surfaces 12 and 15 are separated due to deterioration of the lubricating oil. As a result, the size and weight of the continuously variable transmission 1 can be substantially reduced as much as possible. In particular, if the through holes 32 are used, the weight of the roller 17 can be further reduced.

On the other hand, in the embodiment of FIG. 4B, a plurality of fan-shaped through holes 46 are provided. Thus, the roller 17 has a structure in which the central boss 46 and the outer ring 47 are connected by the radial rib 48. In the present embodiment,
The heat radiation area of the roller 17 can be further increased to enhance the cooling effect. In each example of FIGS. 4A and 4B, a recess may be provided instead of the through holes 44 and 46. Next, FIG. 5 shows still another embodiment of the present invention. Referring to FIG. 5, in the present embodiment, a passage 50 that penetrates the input shaft 3 as a rotating shaft in the longitudinal direction and passes the lubricating oil is provided, and the passage 50 radially extends in the radial direction of the input shaft 3. A plurality of passages 51 extending are provided. Then, the lubricating oil from each passage 51 is
A lubricating oil spray port 52 for spraying toward the side surface 17 a of the input shaft 3 is provided on the peripheral surface 3 a of the input shaft 3.

In the present embodiment, the lubricating oil can be effectively supplied to each of the rollers 17 disposed around the input shaft 3 by using the centrifugal force of the rotation of the input shaft 3. , Can enhance the cooling effect. Then
FIG. 6 shows still another embodiment of the present invention. Referring to FIG. 6, in the present embodiment, each of disks 5, 6, 10
A large number of grooves 53 for holding the oil film are formed on the raceway surfaces 12 and 15. The groove 53 is preferably formed radially, but it is sufficient if it extends radially outward from the center of each of the disks 5, 6, and 10. In the present embodiment, the oil film holding on the raceway surfaces 12 and 15 can be improved, the generation of frictional heat can be suppressed, and the durability of the disks 5, 6, 10 and the rollers 17 can be improved.

As shown in FIGS. 7A to 7C, a large number of grooves 54 and 55 for retaining an oil film may be formed on the peripheral surface 17b of the roller 17. FIG. 7 (a)
In the figure, inverted V-shaped grooves 54 are formed at regular intervals in the circumferential direction of the roller 17. The V-shaped tip of the groove 54 extends in the anti-rotation direction of the roller 17. Thereby, the lubricating oil in the groove 54 is brought closer to the center in the width direction of the roller 17 with the rotation of the roller 17, and the lubricating oil holding property can be further improved.

In FIG. 7B, a pair of grooves 55, 55 having a C-shape are provided. Roller 1 is the tip of the letter "C"
7 is the same as that of the embodiment shown in FIG. As shown in FIG. 7C, only one of the pair of grooves 55 in FIG. 7B may be provided. Only one piece was provided. FIG. 7 (a),
In each of the examples (b) and (c), it is possible to contribute to oil film retention. 6 and 7 may be combined. In this case, a synergistic effect of retaining the oil film can be expected.

The present invention is not limited to the above embodiment, and various modifications can be made within the scope of the present invention.

[Brief description of the drawings]

FIG. 1 is a partially cutaway schematic view of a toroidal type continuously variable transmission according to an embodiment of the present invention.

2A is a schematic side view of a roller and a carriage according to the embodiment of FIG. 1, and FIG. 2B is a schematic plan view of the roller and the carriage.

FIG. 3A is a schematic side view of a roller and a carriage according to another embodiment of the present invention, and FIG. 3B is a plan view of a main part of the roller.

FIGS. 4A and 4B are schematic side views of a roller according to still another embodiment of the present invention.

FIG. 5 is a schematic side view of a main part of a continuously variable transmission according to yet another embodiment of the present invention.

FIG. 6 is a schematic side view of a disk according to still another embodiment of the present invention.

FIGS. 7 (a), (b) and (c) are plan views of rollers according to still another embodiment of the present invention.

FIGS. 8A and 8B are a partially cutaway side view and a schematic plan view of a conventional roller and carriage.

[Explanation of symbols]

A continuously variable transmission 1 variator 3 input shaft 5, 6 input disk 10 output disk 12, 15 track surface S toroidal gap 17 roller 17a side surface 17b peripheral surface 32 first piping 33 second piping 36, 37, 38, 41, 42, 43, 50, 51 Passage 39 First pipe 40 First pipe 44, 46 Through hole 52 Lubricating oil spray port 53, 54, 55 Groove

Claims (5)

[Claims] In a toroidal-type continuously variable transmission in which rollers are arranged across a toroidal gap formed between an input disk and an output disk, a torque transmission area between the rollers and each disk is provided. A means for spraying lubricating oil to a roller or a disk from a position near the toroidal type continuously variable transmission. 2. The toroidal-type continuously variable transmission according to claim 1, wherein said spraying means includes a pipe supported by a carriage rotatably supporting a roller and extending to a position near a torque transmission area. 3. A toroidal-type continuously variable transmission in which a roller is disposed across a toroidal gap formed between an input disk and an output disk, a concave portion or a through hole is provided on a side surface of the roller. A continuously variable toroidal transmission. 4. In a toroidal-type continuously variable transmission in which rollers are disposed across a toroidal gap formed between an input disk and an output disk, the input disk and the output disk are coaxial. A toroidal-type continuously variable transmission, comprising: a passage through which a lubricating oil passes through a rotating shaft, and a lubricating oil spray port provided on a peripheral surface of the rotating shaft and spraying the lubricating oil from the passage. Machine. 5. A toroidal-type continuously variable transmission in which rollers are disposed across a toroidal gap formed between an input disk and an output disk, and a raceway surface of the disks and a peripheral surface of the rollers. Wherein a plurality of grooves for retaining an oil film are formed in at least one of the toroidal type continuously variable transmissions.