JP2002070972A - Friction roller type transmission - Google Patents

Abstract

(57) Abstract: To improve lubricity between each end face of a guide roller 10a and a wedge roller, and between an inner peripheral surface of each roller 10a and an outer peripheral surface of each pivot 7a. A washer (2) is provided between both axial end surfaces of each roller (10a) and side surfaces of a lid (2a) and a connecting plate (8a).
8a, 28a are provided on at least one side face with concave grooves 37, 3
7 is provided. Through the respective concave grooves 37, 37, the side surfaces of the respective washers 28a, 28a and the respective rollers 10a
And the radial needle bearings 12 existing between the rollers 10a and the pivots 7a.
In addition, the lubricant is easily distributed. As a result, even when a high-speed operation or a long-time operation is performed, for example, the sliding portions and the radial needle bearing 12 can be sufficiently lubricated, and excellent durability can be realized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a friction roller type transmission which transmits a rotary motion while reducing or increasing speed by being incorporated in a rotary drive portion of, for example, an electric vehicle, a hybrid vehicle, an electric wheelchair, and a machine tool. Regarding improvement. In particular, the present invention realizes a friction roller type transmission having excellent durability by lubricating a portion where a lubricant is difficult to spread.

[0002]

2. Description of the Related Art A friction roller type transmission generates less noise even when operated at a high speed than a gear type transmission such as a planetary gear type. For this reason, for example, a friction roller type transmission is mounted on the output portion of the electric motor and used as a speed reducer,
A structure for reducing the rotational movement of the electric motor and increasing the torque is described in, for example, JP-A-8-210455. The general friction roller type transmission described in this publication and the like, the contact pressure between the peripheral surfaces of each roller,
Regardless of the fluctuation of the torque to be transmitted, it is always kept constant.

On the other hand, for the purpose of ensuring good transmission efficiency, the contact pressure is reduced when the torque to be transmitted is small, and the contact pressure is reduced when the torque to be transmitted is large. U.S. Pat.
No. 89 describes a friction roller type transmission as shown in FIGS. In this conventional friction roller type transmission, an inner half portion of a center roller 4 (FIG. 7) is fixed in a fixed housing 3 comprising a bottomed cylindrical main body 1 and a lid 2 closing a base end opening of the main body 1. Of the cover 2 is inserted through a through hole 5 formed substantially in the center of the lid 2. The through hole 5 is provided at a position slightly deviated from the center of the lid 2. The end of the input shaft 6 is connected and fixed to the outer half (left half of FIG. 7) of the center roller 4 protruding from the lid 2.

Also, three pivots 7a, 7b, 7c are provided inside the housing 3 and around the center roller 4.
Are arranged in parallel with the center roller 4.
That is, one end (the left end in FIG. 7) of each of the pivots 7a, 7b, 7c is supported by the lid 2, and the other end (FIG. 7).
At the right end of the support plate 8 is supported by the connecting plate 8. Of these three pivots 7a, 7b, 7c, one pivot 7a located at the upper center of FIGS. 8 to 9 has a fitting hole formed at both ends thereof in the lid 2 and the connecting plate 8. Press fit. Therefore, the pivot 7a is not displaced in the circumferential direction or the diametrical direction in the housing 3.

On the other hand, the remaining two pivots 7b and 7c located on the lower left and right sides in FIGS. 8 and 9 have both ends with respect to the lid 2 and the connecting plate 8 in the circumferential direction of the housing 3. And it is supported so that it can be displaced slightly in the diameter direction. For this purpose, the pivots 7b, 7
As shown in FIG. 9, support holes 9, 9 having an inner diameter larger than the outer diameters of the pivots 7b, 7c are formed in portions corresponding to both ends of the support holes 9c. Both ends of the pivots 7b and 7c are loosely engaged. And
A guide roller 10 and wedge rollers 11a and 11b, which are intermediate rollers, are rotatably supported by radial needle bearings 12, respectively, around intermediate portions of the pivots 7a, 7b and 7c. The connecting plate 8 is an inner surface of the lid 2 (a surface on the space side where the guide roller 10 and the wedge rollers 11a and 11b are installed,
A part of the right side of FIG. 7) collides with the projections 13, 13 projecting from the guide roller 10 and the wedge rollers 11 a, 11 b and is connected to the lid 2 by connection bolts 14, 14. It is fixed.

An annular outer ring 15 is rotatably provided inside the housing 3 at a portion surrounding the guide roller 10 and the wedge rollers 11a and 11b.
The central portion of the inner peripheral surface of the outer ring 15 is projected inward in the diameter direction to form a bank-shaped convex portion 16, and the inner peripheral surface of the convex portion 16 is a second cylindrical surface 17. The second cylindrical surface 17 and a third cylindrical surface 18, which is the outer peripheral surface of the guide roller 10 and the wedge rollers 11a and 11b,
18 is freely contactable. Also, the outer ring 15 has
The outer diameter end of the coupling bracket 19 is externally fitted and fixed, and the inner end (the left end in FIG. 7) of the output shaft 20 is coupled and fixed to the center of the coupling bracket 19. This output shaft 20
A second through hole 21 formed in the center of the main body 1 constituting the housing 3 is rotatably inserted through the second through hole 21 and protrudes out of the housing 3.

Each of the third cylindrical surfaces 1 as outer peripheral surfaces of the guide roller 10 and the wedge rollers 11a and 11b.
Reference numerals 8 and 18 respectively contact a first cylindrical surface 22 provided on the outer peripheral surface of the center roller 4 and a second cylindrical surface 17 provided on the inner peripheral surface of the outer ring 15. The center of the center roller 4 and the centers of the output shaft 20 and the outer ring 15 are eccentric to each other. That is, as described above, the through hole 5 through which the center roller 4 is inserted is provided at a position slightly deviated from the center of the housing 3, whereas the second through hole through which the output shaft 20 is inserted. The hole 21 is provided in the housing 3
Is provided at the center. The output shaft 20 and the outer ring 15 rotatably supported inside the second through hole 21 are concentric with each other. Therefore, the center roller 4 and the outer ring 15
The output shaft 20 is eccentric to the output shaft 20 by an amount δ (see FIG. 7) of the through hole 5 from the center of the housing 3. The guide roller 10 and the wedge rollers 11a, 11b are present between the first cylindrical surface 22 provided on the outer peripheral surface of the center roller 4 and the second cylindrical surface 17 provided on the outer ring 15. The width dimension of the annular space 23 provided with is uneven in the circumferential direction by an amount corresponding to the eccentric amount of δ.

As described above, the outer diameters of the guide roller 10 and the wedge rollers 11a and 11b are made different from each other by the difference in the width of the annular space 23 in the circumferential direction. That is, the wedge roller 1 located on the side where the center roller 4 is eccentric with respect to the outer ring 15 (the lower side in FIGS. 7 to 9).
The diameters of 1a and 11b are the same and relatively small. On the other hand, the diameter of the guide roller 10 located on the opposite side (upper side in FIGS. 7 to 9) of the outer ring 15 with respect to the eccentricity of the center roller 4 is made larger than those of the two wedge rollers 11a and 11b. I have. Then, these three guide rollers 1 each being an intermediate roller.
0 and the third cylindrical surfaces 18, 18 which are the outer peripheral surfaces of the wedge rollers 11a, 11b,
2 and 17 are abutted.

The above-mentioned 1 is an intermediate roller.
Guide rollers 10 and two wedge rollers 11
a, 11b, the pivot 7 supporting the guide roller 10
a is fixed in the housing 3 as described above. On the other hand, the pivots 7b and 7c supporting the wedge rollers 11a and 11b freely support a slight displacement in the circumferential direction and the diametric direction in the housing 3 as described above. Therefore, the wedge roller 11
a and 11b are also slightly displaceable in the circumferential direction and the diametrical direction in the housing 3. A compression coil spring 25 mounted in the cylinder holes 24, 24 of the lid 2,
Each of the wedge rollers 11a,
Each of the pivots 7b and 7c that support the
b, wedge roller 11a rotatably supported by 7c,
In order to move 11b toward the narrow portion of the annular space 23, it is elastically lightly pressed.

In the case of the conventional friction roller type transmission constructed as described above, the rotation of the center roller 4 connected to the input shaft 6 is caused by rotation of the first cylindrical surface provided on the outer peripheral surface of the center roller 4. 22, guide roller 10 and wedge roller 1
Via respective inner diameter side contact portions 26, 26 which are contact portions with the third cylindrical surfaces 18, 18 which are outer peripheral surfaces of 1a, 11b,
These guide roller 10 and any wedge roller 1
It is transmitted to 1a and 11b. Further, these guide rollers 10
And the rotation of one of the wedge rollers 11a, 11b
Each of the third cylindrical surfaces 18, 18 is in contact with a second cylindrical surface 17 provided on the inner peripheral surface of the outer ring 15, and each outer diameter side contact portion 27, 27 It is transmitted to the outer ring 15. Then, the output shaft 20 fixedly connected to the outer ring 15 rotates.

When the center roller 4 rotates clockwise (or counterclockwise) in FIGS. 8 and 9 and the outer race 15 also rotates counterclockwise (or clockwise), the right pivot 7b in FIGS. The wedge roller 11a (or 11b) rotatably supported by the (or left pivot 7c) is provided in the annular space 23 existing between the first and second cylindrical surfaces 22, 17 in the annular space 23. The narrow part of
9 (lower central portion of the image No. 9). On the other hand, the wedge roller 11b (or 11a) rotatably supported by the left pivot 7c (or the right pivot 7b) in FIGS. 8 to 9 (or the right central part in FIGS. 8 to 9). As a result, the right pivot 7b
The third cylindrical surface 18, which is the outer peripheral surface of the wedge roller 11a (or 11b) rotatably supported on the (or left pivot 7c), strengthens the first cylindrical surface 22 and the second cylindrical surface 17 with each other. Press. Then, the wedge roller 11a
(Or 11b), an inner diameter side contact portion 26 which is a contact portion between the third cylindrical surface 18 and the first cylindrical surface 22;
The contact pressure of the outer diameter side contact portion 27 which is the contact portion between the third cylindrical surface 18 and the second cylindrical surface 17 with respect to the wedge roller 11a (or 11b) increases.

When the contact pressure of the inner and outer contact portions 26 and 27 with respect to the wedge roller 11a (or 11b) increases, at least one of the center roller 4 and the outer ring 15 is formed. However, they are slightly displaced in the respective diametrical directions based on an assembling gap or elastic deformation. As a result, an inner diameter side contact portion 26 which is a contact portion between the third cylindrical surface 18 which is the outer peripheral surface of the guide roller 10 and the first cylindrical surface 22 which is the outer peripheral surface of the center roller 4, and The contact pressure of the outer diameter side contact portion 27 which is the contact portion between the third cylindrical surface 18 which is the outer peripheral surface of the guide roller 10 and the second cylindrical surface 17 which is the inner peripheral surface of the outer ring 15 is high. Become.

The right pivot 7b (or the left pivot 7)
c) The force for moving the wedge roller 11a (or 11b) rotatably supported in the annular space 23 toward the narrow portion of the annular space 23 in the annular space 23 is applied from the center roller 4 to the outer ring 15 Changes according to the magnitude of the torque transmitted to the motor. That is, as the driving torque of the center roller 4 increases, the wedge roller 11a (or 11
The force for moving b) toward the narrow portion of the annular space 23 increases. The greater the force, the greater the contact pressure between the inner and outer diameter contact portions 26 and 27. Conversely, when the driving torque is small, these inner and outer diameter side contact portions 26, 27
Contact pressure is small.

In the conventional structure described above, of the three intermediate rollers, only one intermediate roller is used as the guide roller 10, and the remaining two intermediate rollers are used as the wedge rollers 11a and 11a.
1b. On the other hand, a structure in which two intermediate rollers among the three intermediate rollers are used as guide rollers and only the remaining one intermediate roller is used as a wedge roller is conventionally known. In the case of a friction roller type transmission having such a structure, it is possible to transmit only a rotational force in one direction, and slip occurs internally for a rotational force in the opposite direction,
It does not transmit this torque. In other words, it has a clutch function of transmitting torque only in one direction.

[0015]

In the case of the conventional friction roller type transmission as described above, the guide roller 10 and the wedge roller 11 which are respectively intermediate rollers are used as they are.
The sliding speed between the axial end surfaces of the a and 11b and the side surfaces of the lid 2 and the connecting plate 8 facing these end surfaces is increased,
The rotational resistance of each of the intermediate rollers 10, 11a, 11b increases. As shown in FIG. 10, each of the intermediate rollers 10, 11a, 11b (11a, 11a, 11b, 11a, 11b) is used to prevent the rotation resistance from increasing due to such a cause and to smoothly rotate the intermediate rollers 10, 11a, 11b. 11b is FIG.
9) between the axial end faces and the side faces of the lid 2 and the connecting plate 8 are partially provided.

However, when the washers 28, 28 are provided in this manner, the gaps between the intermediate rollers 10, 11a, 11b and the side surfaces of the lid 2 and the continuous plate 8 are closed by the washers 28, 28. The lubricant, such as traction oil and traction grease, existing in the housing 3 (see FIGS. 7 to 9) is used for the intermediate rollers 10, 11a,
11b, each pivot 7a, 7b, 7c (7b, 7c
8 to 9). In addition, each of the intermediate rollers 10, 11a, and 11b is reduced by the amount of the clearance.
It is also difficult to take in the lubricant at the respective sliding contact portions between both end surfaces of the washer and the side surfaces of the washers. As a result, the sliding portions of the intermediate rollers 10, 11a, 11b and the washers 28, 28, and the intermediate rollers 10, 11a, 11b,
11a, 11b and the above-mentioned pivots 7a, 7b, 7c
Radial needle bearing 12 between the outer peripheral surface of
At 12, the lubricant tends to be depleted. Then, when the lubricant is depleted, the friction roller type transmission is subjected to severe conditions,
For example, when a high-speed operation or an operation is performed for a long time, damages such as peeling and seizure are likely to occur in the sliding contact portions and the radial needle bearings 12 and 12, and sufficient durability may not be exhibited. There is. In view of such circumstances, the present invention has been made to realize a friction roller type transmission having excellent durability.

[0017]

A friction roller type transmission according to the present invention comprises a center roller having an outer peripheral surface as a first cylindrical surface, similarly to the above-described conventionally known friction roller type transmission. An outer ring provided with an inner peripheral surface as a second cylindrical surface around the center roller so as to freely rotate relative to the center roller, and an annular ring between the first cylindrical surface and the second cylindrical surface. In the space, a plurality of pivots arranged in parallel with the center roller, a plurality of intermediate rollers rotatably supported by each of the pivots, and each having an outer peripheral surface as a third cylindrical surface, A ring-shaped washer is provided between both end surfaces in the axial direction of the intermediate roller and members facing the respective end surfaces. Then, based on the frictional engagement between the third cylindrical surface and the first cylindrical surface and the second cylindrical surface, rotation of one of the center roller and the outer ring from the member to the other member is performed. The transmission of power is free. In particular, in the friction roller type transmission of the present invention, at least one concave groove is provided on at least one side surface of each of the above-mentioned washers so as to be continuous from the inner peripheral edge to the outer peripheral edge.

[0018]

In the case of the friction roller type transmission of the present invention constructed as described above, at least one side surface of a washer provided between both end surfaces in the axial direction of the intermediate roller and members opposed to these end surfaces. The sliding grooves between the side surfaces of the washers and both end surfaces of the intermediate rollers, and the pivots that rotatably support the intermediate rollers and the intermediate rollers are provided through the concave grooves. In the meantime, the lubricant is easily distributed. Therefore, the friction roller type transmission is subject to severe conditions,
For example, even when a high-speed operation or a long-time operation is performed, sufficient lubrication can be achieved between the inner peripheral surface of each of the sliding contact portions and each of the intermediate rollers and the outer peripheral surface of each pivot to ensure excellent durability. it can.

[0019]

1 to 4 show a first embodiment of the present invention, corresponding to claims 1 to 3. FIG. still,
In the illustrated example, two intermediate rollers of the three intermediate rollers are used as guide rollers 10a and 10b, and only one intermediate roller is used as a wedge roller 11, so that a one-way friction roller type transmission can be provided. This figure shows a case where the present invention is implemented with a structure having a clutch function.

The friction roller type transmission of this embodiment also has a bottomed cylindrical body 1a made of steel or aluminum alloy and a base opening of the body 1a, similarly to the above-described conventional structure. A stationary housing 3a comprising a steel lid 2a
Having. The inner half (left half in FIG. 1) of the center roller 4a is inserted into the housing 3a through a through hole 5a formed in the center of the lid 2a. In the illustrated example, the center roller 4a is provided in the through hole 5a,
9 rotatably supports. In addition, this through hole 5a
Is located substantially at the center of the lid 2a, and the housing 3a
It is provided at a position slightly deviated from the center of (the main body 1a). At the outer end (right end in FIG. 1) of the center roller 4a, a drive shaft 30 constituting a rotating shaft of an electric motor (not shown) is provided integrally with the center roller 4a.

Also, three pivots 7a, 7b, 7 are provided inside the housing 3a and around the center roller 4a.
c are arranged in parallel with the center roller 4a. That is, one end (the right end in FIG. 1) of each of the pivots 7a, 7b, 7c is supported by the lid 2a, and the other end (the left end in FIG. 1) is supported by the connecting plate 8a. Of these pivots 7a, 7b, 7c, the two pivots 7a, 7b located at the lower center and upper left side in FIG. 2 have both ends formed on the lid 2a and the connecting plate 8a. It is press-fitted and fixed in the holes 31, 31. Therefore, these pivots 7a and 7b are not displaced in the circumferential direction or the diametrical direction in the housing 3a. On the other hand, the remaining one pivot 7c located on the upper right side in FIG. 2 has both ends slightly displaceable with respect to the lid 2a and the connecting plate 8a in the circumferential direction and the diametric direction of the housing 3a. I support it. For this reason, a part of the lid 2a and a part of the connecting plate 8a which is aligned with both ends of the pivot 7c is provided with the pivot 7
A supporting hole 9a having a width and a length larger than the outer diameter of the supporting shaft 9c is formed, and both ends of the pivot 7c are loosely engaged with the supporting holes 9a.

Guide rollers 10a, 10b and wedge rollers 11, which are intermediate rollers, are rotatably supported by radial needle bearings 12, respectively, around the intermediate portions of the pivots 7a, 7b, 7c. . The connecting plate 8a is connected to the inner surface of the lid 2a (the guide rollers 10a and 10b and the wedge roller 11a).
1 and a part of the left side of FIG. 1) against the projections 13 and 13 projecting from the guide rollers 10a and 10b and the wedge roller 11, and connecting bolts 14 and 14, it is connected and fixed to the lid 2a. Also, washers 28a, 28a are provided between the axial end surfaces of the guide rollers 10a, 10b and the wedge roller 11 and the connecting plate 8a and the lid 2a, respectively, and these intermediate rollers 10a, 10b, 11 The rotation of is performed smoothly.

In the case of this example, as shown in FIG. 4, each of the washers 28a, 28a is formed by forming a metal plate material such as steel or copper alloy into an annular shape. (B) in the left-right direction of the intermediate rollers 10a,
A plurality of (four in the illustrated example) concave grooves 37, 37 are provided on the side surface 38 on the side that comes into sliding contact with the end surfaces of Ob, 11 so as to be continuous from the inner peripheral edge to the outer peripheral edge. These concave grooves 37 are formed by press working, and FIG.
As shown in the figure, the side surface 38 of the washer 28a and the concave curved surface 39 forming the bottom of each of the concave grooves 37, 37 are smoothly connected by the convex curved surfaces 40, 40 having an arc-shaped cross section.

The washer 28a, 28a
Are externally fitted to the pivots 7a, 7b, 7c, and are clamped between the end faces of the intermediate rollers 10a, 10b, 11 and the side surfaces of the lid 2a and the connecting plate 8a. In this state, the side surfaces 38, 38 of the washers 28a, 28a provided with the concave grooves 37, 37 and the end surfaces of the intermediate rollers 10a, 10b, 11 are in sliding contact with each other. Accordingly, the lubricant such as traction oil and traction grease existing in the housing 3a passes through the respective grooves 37, 37, and through the washers 28a, 2c.
8a and the intermediate rollers 10a,
0b, 11 and the sliding surfaces of the intermediate rollers 10a, 10b, 11 and the pivots 7
The radial needle bearings 12, 12 existing between the outer peripheral surfaces of the a, 7b, 7c are efficiently fed.

A cylindrical outer ring 15a having a bottom is provided in a portion surrounding the guide rollers 10a and 10b and the wedge roller 11 inside the housing 3a.
A second cylindrical surface 17 is provided on the inner peripheral surface of 5a. The second cylindrical surface 17 and the guide roller 10
a, 10b and the third cylindrical surfaces 18, 18, which are the outer peripheral surfaces of the wedge roller 11, can be in contact with each other. The inner end (right end in FIG. 1) of the output shaft 20a is connected to the center of the outer surface (left surface in FIG. 1) of the bottom plate portion 32 of the outer ring 15a. The output shaft 20a is inserted through the inside of a support cylinder 33 formed at the center of the main body 1a constituting the housing 3a, and the output shaft 20a is inserted inside the support cylinder 33.
Are rotatably supported by ball bearings.

The third cylindrical surfaces 18, 18 which are the outer peripheral surfaces of the guide rollers 10a, 10b and the wedge roller 11, are first cylindrical surfaces provided on the outer peripheral surface of the center roller 4a, respectively. 22 and the second cylindrical surface 17 provided on the inner peripheral surface of the outer ring 15a.
The center of the center roller 4a and the centers of the output shaft 20a and the outer ring 15a are eccentric to each other. That is, as described above, the through-hole 5a through which the center roller 4a is inserted is provided at a position slightly deviated from the center of the housing 3a, whereas the support cylindrical portion 3 through which the output shaft 20a is inserted.
3 is provided at the center of the housing 3a. Further, the output shaft 20 rotatably supported inside the support cylindrical portion 33.
a and the outer ring 15a are concentric with each other. Therefore, the center roller 4a, the outer ring 15a, and the output shaft 20a are eccentric with respect to each other by an amount of deviation δ (see FIG. 1) of the through hole 5a from the center of the housing 3a. And
The guide rollers 10a, 10b and the wedge roller 11 are provided between the first cylindrical surface 22 provided on the outer peripheral surface of the center roller 4a and the second cylindrical surface 17 provided on the outer ring 15a. The width dimension of the formed annular space 23 is unequal in the circumferential direction by an amount corresponding to the eccentric amount of δ.

The width of the annular space 23 is made uneven in the circumferential direction.
a, 10b and the wedge roller 11 have different outer diameters. That is, the guide roller 1 located on the side (upper side in FIG. 2) where the center roller 4a is eccentric with respect to the outer ring 15a.
Ob and the wedge roller 11 have the same diameter and are relatively small. On the other hand, the diameter of the guide roller 10a located on the opposite side (the lower side in FIG. 2) of the center roller 4a to the eccentricity with respect to the outer ring 15a is
It is larger than the guide roller 10b and the wedge roller 11. The third cylindrical surfaces 18, 18 which are the outer peripheral surfaces of the three guide rollers 10a, 10b and the wedge roller 11, each of which is an intermediate roller.
Are in contact with the first and second cylindrical surfaces 22 and 17.

The above-mentioned 2 is an intermediate roller.
Among the guide rollers 10a and 10b and the one wedge roller 11, the pivots 7a and 7b supporting both the guide rollers 10a and 10b are connected to the housing 3 as described above.
a. In contrast, wedge roller 1
The pivot 7c supporting the first member 1 freely supports a slight displacement in the circumferential direction and the diametric direction in the housing 3a as described above. Therefore, the wedge roller 11 is also slightly displaceable in the circumferential direction and the diametrical direction in the housing 3a. And the lid 2a
And the elastic member such as a compression coil spring 25 mounted in the cylinder hole 24a of the connecting plate 8a.
1 is elastically pressed so as to move the wedge roller 11 rotatably supported on the pivot 7c toward a narrow portion of the annular space 23.
In the illustrated example, the compression coil springs 25 press the pressing pins 36 having the outwardly flanged flanges 35 at the respective ends (the lower left end in FIG. 2). Both ends of the pivot 7c are pressed in the same direction.

An insertion hole 41 for inserting a rod-shaped tool is provided in a part of the lid 2a facing the pivot 7c.
Is provided. That is, when the center roller 4a is inserted inside the guide rollers 10a, 10b and the wedge roller 11, the rod-shaped tool is inserted into the insertion hole 41, and the pivot 7c is resilient to the compression coil spring 25. Press against. Then, the wedge roller 11 supported on the pivot 7c is displaced to a wide portion of the annular space 23, and the diameters of the guide rollers 10a and 10b and the inscribed circle of the outer peripheral surface of the wedge roller 11 are set to the center. It is made larger than the outer diameter of the roller 4a. Therefore, when assembling the center roller 4a, the center roller 4a
It is possible to prevent the first cylindrical surface 22 provided on the outer peripheral surface and the third cylindrical surfaces 18, 18 which are the outer peripheral surfaces of the guide rollers 10a, 10b and the wedge roller 11 from being scratched. The insertion hole 41 is closed after the assembly is completed.

In the friction roller type transmission of the present invention having the above-described structure, the rotation of the center roller 4a provided integrally with the drive shaft 30 is performed by rotating the center roller 4a provided on the outer peripheral surface of the center roller 4a. One cylindrical surface 22, guide rollers 10a,
Each inner diameter side contact portion 2 which is a contact portion between the outer peripheral surface of the wedge roller 11 and the third cylindrical surface 18, 18.
6 and 26, the guide rollers 10a and 10b
And transmitted to the wedge roller 11. Further, the rotation of the guide rollers 10a and 10b and the wedge roller 11 is a contact portion between the third cylindrical surfaces 18 and 18 and the second cylindrical surface 17 provided on the inner peripheral surface of the outer ring 15a. The power is transmitted to the outer ring 15a via the outer diameter side contact portions 27, 27. The output shaft 2 coupled to the outer ring 15a
0a is driven to rotate in the opposite direction to the center roller 4a.

When the center roller 4a rotates counterclockwise in FIG. 2 so that the output shaft 20a is driven to rotate by the drive shaft 30, the wedge roller 11 causes the force applied from the center roller 4a and the compression coils to rotate. Due to the resiliency of the spring 25, the annular space 23 moves between the first and second cylindrical surfaces 22 and 17 toward a narrow portion (the upper central portion in FIG. 2) of the annular space 23. I do. As a result, the third cylindrical surface 18 as the outer peripheral surface of the wedge roller 11 strongly presses the first cylindrical surface 22 and the second cylindrical surface 17. Then, an inner diameter side contact portion 26 which is a contact portion between the third cylindrical surface 18 related to the wedge roller 11 and the first cylindrical surface 22, and the third cylindrical surface 18 related to the wedge roller 11 and Second cylindrical surface 17
The contact pressure of the outer diameter side contact portion 27 which is the contact portion with the contact hole increases.

The inner diameter side of the wedge roller 11;
When the contact pressure between the outer diameter side contact portions 26 and 27 increases, at least one of the center roller 4a and the outer ring 15a is displaced in the diametrical direction based on an assembling clearance or elastic deformation. Slightly displaced with respect to. As a result,
Guide rollers 10a, 10 as the remaining two intermediate rollers
The two inner diameter side contact portions 26, 26, which are the contact portions between the third cylindrical surfaces 18, 18 which are the outer peripheral surface of the center roller b and the first cylindrical surface 22 provided on the outer peripheral surface of the center roller 4a. And two outer diameter sides which are abutting portions of the third cylindrical surfaces 18 and 18 which are the outer peripheral surfaces of the guide rollers 10a and 10b and the second cylindrical surface 17 provided on the inner peripheral surface of the outer ring 15a. Contact part 27,
27, the contact pressure increases. Then, the outer ring 15a and the output shaft 20a rotate clockwise in FIG.

The force for moving the wedge roller 11 in the annular space 23 toward the narrow portion of the annular space 23 is applied from the center roller 4a to the outer ring 1.
It changes according to the magnitude of the torque transmitted to 5a. That is, as the driving torque of the center roller 4a increases,
The force for moving the wedge roller 11 toward the narrow portion of the annular space 23 increases. The greater the force, the greater the contact pressure between the inner and outer diameter contact portions 26 and 27. Conversely, when the driving torque is small, the contact pressures of the inner and outer contact portions 26 and 27 are small. For this reason, the contact pressure between the inner and outer diameter contact portions 26 and 27 is adjusted to an appropriate value according to the magnitude of the torque to be transmitted between the drive shaft 30 and the output shaft 20a. As a result, the transmission efficiency of the friction roller type transmission can be increased. In this state, the clutch mechanism is turned on.

On the other hand, while the driving shaft 30 is stopped, the outer ring 15a rotates clockwise in FIG.
When the rotation speed of the output shaft 20a is higher than the speed corresponding to the rotation speed of the drive shaft 30, the wedge roller 11 causes the compression coil springs 25, 25 to move by the force applied from the outer ring 15a. In the annular space 23, the annular space 23 moves toward a wide portion (the central portion on the right side in FIG. 2). As a result, the third cylindrical surface 18 which is the outer peripheral surface of the wedge roller 11 is formed.
Does not press the first cylindrical surface 22 and the second cylindrical surface 17. The wedge roller 11 and the inner cylindrical contact portions 26, 26, which are the contact portions of the third cylindrical surfaces 18, 18 with the guide rollers 10a, 10b and the first cylindrical surface 22; Wedge roller 11
In addition, the contact pressure of the outer diameter side contact portions 27, 27, which are the contact portions between the third cylindrical surfaces 18, 18 and the second cylindrical surface 17, with respect to the guide rollers 10a, 10b is reduced or lost. I do. As a result, the rotation of the outer ring 15a is not transmitted to the drive shaft 30. In this state, the clutch mechanism is turned off.

Further, in the case of this embodiment, each of the washers 2
8a, 28a, the respective sliding contact portions between the side surfaces 38, 38 of the washers 28a, 28a and the end surfaces of the intermediate rollers 10a, 10b, 11 and the intermediate portions thereof. The lubricant is easily distributed to the radial needle bearings 12, 12 existing between the rollers 10a, 10b, 11 and the pivots 7a, 7b, 7c. In addition, the concave curved surface 39 forming the bottom of each of the concave grooves 37, 37 and the side surface 38 of the washer 28a, 28a are smoothly connected by the convex curved surfaces 40, 40 having an arc-shaped cross section. The lubricant can be effectively fed into the contact portion. Further, each of the intermediate rollers 10a, 10
The end faces of b and 11 are not damaged by the opening edges of the concave grooves 37 and 37. Therefore, even when the friction roller type transmission is subjected to severe conditions, for example, a high-speed operation or an operation for a long time, each of the sliding contact portions and each of the radial needle bearings 1 are required.
Lubrication of 2, 12 can be sufficiently achieved, and excellent durability can be exhibited. Further, since the formation of the grooves 37, 37 is performed all at once by pressing, the formation of the grooves 37, 37 can be performed efficiently, and the cost increase due to the provision of the grooves 37, 37 can be reduced. Can be kept low. Further, if the operations of forming the concave grooves 37, 37 and the operations of forming the washers 28a, 28a are performed at the same time, the cost can be further reduced.

In the illustrated example, the shape and the number of the grooves 37 are four in the radial direction.
The shape and the number of 7, 37 are not limited to such. For example, various shapes and numbers as shown in FIGS. 5A to 5F can be adopted. For example, FIG. 1A shows a groove 3 in which two parallel grooves are arranged as a set.
Figure 7 (b), in which four sets of 7, 37 are arranged in the radial direction.
In FIG. 3C, four sets of concave grooves 37, 37 arranged as one set of three parallel grooves are arranged in the radial direction, and in FIG. Those arranged in the radial direction and those shown in FIG.
7 are arranged in the radial direction. Further, FIG.
The one shown in FIG. 3 has four concave grooves 37, 37 provided in a state inclined with respect to the rotation direction, and the one shown in FIG. The grooves 37 are provided so as to be inclined with respect to the rotation direction. As described above, the shapes and the numbers of the concave grooves 37, 37 are optimized in consideration of the use state and the like.

Next, FIG. 6 shows a second example of the embodiment of the present invention, which also corresponds to claims 1 to 3. In the case of this example, both axial side surfaces 3 of the washers 28b, 28b
8 and 38 are provided with a plurality of concave grooves 37 and 37, respectively. In this manner, the intermediate rollers 10a, 10b, 11 (10b,
11 is shown in FIG. 2) and each of the pivots 7a, 7b, 7c.
(See FIG. 2 for 7b and 7c) Lubrication of each radial needle bearing 12 existing between the outer peripheral surface and the outer peripheral surface can be more sufficiently achieved. In addition, lubrication between the washers 28b, 28b, the lid 2a and the connecting plate 8a can be improved. As the shape and number of the concave grooves 37 provided on the both side surfaces 38, 38, of course, various shapes and numbers as shown in FIG. 5 described above can be adopted. Other configurations and operations are the same as those of the first example.

[0038]

Since the present invention is constructed and operates as described above, it is possible to secure the lubrication of the portion where the lubricant hardly spreads, and to realize a friction roller type transmission having excellent durability.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first example of an embodiment of the present invention.

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

FIG. 3 is an enlarged view of part B of FIG.

4A and 4B are views showing the washer taken out, wherein FIG. 4A is a front view, FIG. 4B is a cross-sectional view taken along line CC of FIG. 4A, and FIG. 4C is a cross-sectional view taken along line DD of FIG.

FIG. 5 is a view similar to FIG. 4 (a), showing six examples of different shapes of concave grooves.

FIG. 6 is a view similar to FIG. 3, showing a second example of the embodiment of the present invention.

FIG. 7 is a sectional view showing a first example of a conventional structure.

FIG. 8 is a sectional view taken along the line EE of FIG. 7;

FIG. 9 is a sectional view taken along the line FF in FIG.

FIG. 10 is a view similar to FIG. 3, showing a second example of the conventional structure.

[Explanation of symbols]

 1, 1a main body 2, 2a lid 3, 3a housing 4, 4a center roller 5, 5a through hole 6 input shaft 7a, 7b, 7c pivot 8, 8a connecting plate 9, 9a support hole 10, 10a, 10b guide roller 11 , 11a, 11b Wedge roller 12 Radial needle bearing 13 Projection 14 Connection bolt 15, 15a Outer ring 16 Projection 17 Second cylindrical surface 18 Third cylindrical surface 19 Coupling bracket 20, 20a Output shaft 21 Second through hole 22 First cylindrical surface 23 Annular space 24, 24a Cylinder hole 25 Compression coil spring 26 Inner diameter contact portion 27 Outer diameter contact portion 28, 28a, 28b Washer 29 Ball bearing 30 Drive shaft 31 Fitting hole 32 Bottom plate 33 Support tube part 34 Ball bearing 35 Flange part 36 Press pin 37 Depressed groove 38 Side surface 39 Concave curved surface 40 Convex curved surface 41 Insertion hole

Continued on the front page F-term (reference) 3J051 AA01 BA03 BB08 BC02 BC03 BD01 BE03 BE04 EA02 EB03 EC03 ED03 ED08 FA02 FA07 FA10 3J063 AB35 AC01 BA11 CA01 CD02 CD04 CD61 XD03 XD42 XD62 XD73 XE14

Claims (3)

[Claims] 1. A center roller having an outer peripheral surface as a first cylindrical surface, and an outer ring having an inner peripheral surface as a second cylindrical surface and provided around the center roller so as to be rotatable relative to the center roller. A plurality of pivots arranged in parallel with the center roller in an annular space between the first cylindrical surface and the second cylindrical surface, and each pivotally supported by each of the pivots, A plurality of intermediate rollers having an outer peripheral surface as a third cylindrical surface, and a ring-shaped washer provided between axially opposite end surfaces of each of the intermediate rollers and a member opposed to each of these end surfaces, Based on the frictional engagement between the third cylindrical surface, the first cylindrical surface, and the second cylindrical surface, the rotational force from one member of the center roller and the outer ring to the other member is In a friction roller type transmission capable of freely transmitting, each of the above washers 3. A friction roller type transmission, wherein at least one groove is provided on at least one side surface of the groove from the inner peripheral edge to the outer peripheral edge. 2. The concave groove of the washer is formed by press working, and the side surface of the washer and the concave curved surface forming the bottom of the concave groove are smoothly connected by a convex curved surface having an arc-shaped cross section. The friction roller type transmission according to claim 1. 3. The center of the center roller and the center of the outer ring are decentered to make the width of the annular space unequal in the circumferential direction, so that at least one of the plurality of intermediate rollers is at least one intermediate roller. The wedge roller is supported by being displaceable in the circumferential direction of the annular space, and the remaining intermediate roller is used as a guide roller, so that when the center roller and the outer ring rotate in a predetermined direction, the wedge roller and the wedge roller are rotated. The friction roller type transmission according to claim 1, wherein the intermediate roller is movable toward a narrow portion of the annular space.