JPH10252852A - Friction roller type transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a sufficient quantity of oil exist in a contact part, prevent the occurrence of metallic contact, and improve durability by arranging a recessed part capable of freely holding lubricating oil on an outer peripheral surface of the specific number of intermediate rollers among intermediate rollers. SOLUTION: Spiral grooves 49 and 49 are formed on an outer peripheral surface of a guide roller 32 and at least a single wedge roller 31a of a wedge roller being an intermediate roller, and these are formed as a recessed part capable of freely holding lubricating oil. The oil taken in the spiral grooves 49 is sent into respective inside diameter side contact parts 40 by centrifugal force on the basis of autorotating motion of the rollers even after an outside drum 11b slips out of oil gathered on the lower side of a housing 29a. Therefore, a sufficient quantity oil is made to always exist in the vicinity of a contact part of a first cylindrical surface 10a arranged on an outer peripheral surface of a central roller 9b and a third cylindrical surface 18a arranged on the outer peripheral surface of the guide roller 32 and the wedge roller 31a, and the occurrence of metallic contact can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a friction roller type transmission which transmits rotational motion while reducing or increasing speed by being incorporated in various types of mechanical devices. This realizes a structure having a characteristic.

[0002]

2. Description of the Related Art A friction roller type transmission has a planetary gear type or the like.
The noise generated even when operating at high speed is smaller than that of the gear type transmission. For this reason, a structure in which a friction roller type transmission is assembled to an output portion of an electric motor and used as a speed reducer, and the rotational movement of the electric motor is reduced and the torque is increased is described in, for example, Japanese Patent Application Laid-Open No. Hei 8-210455. Have been. 6 and 7 show an electric motor with a friction roller type reduction gear described in this publication.

[0003] A motor case 2 constituting the electric motor 1
Consists of a bottomed cylindrical case body 3 and a lid 4 that closes an opening of one end (lower end in FIG. 6) of the case body 3. The rotation drive shaft 5 is rotatably supported at the center of the inside of the motor case 2. A stator 6 is fixed on the inner peripheral surface of the case body 3, and a rotor 7 is fixed on a portion of the intermediate peripheral surface of the rotary drive shaft 5 facing the inner peripheral surface of the stator 6. The rotation shaft 5 is freely rotatable on the basis of the energization of. A friction roller type speed reducer 8 is provided on the outer surface of the lid 4 (the lower surface in FIG. 6).

This friction roller type speed reducer 8 has one end (the lower end in FIG. 6) of the rotary drive shaft 5 which is the first rotary shaft.
The portion protruding from the outer surface of the lid 4 functions as the center roller 9. The center roller 9 is concentric with the rotation drive shaft 5 and has an outer peripheral surface as a first cylindrical surface 10. An outer drum 11 is provided around the center roller 9.
Are arranged rotatably relative to the center roller 9. In the illustrated example, the outer drum 11 is fitted inside a cylindrical wall portion 12 formed on the outer surface of the lid 4 near the outer diameter, and the outer drum 11 is fixed by a plurality of fixing bolts 21, 21. It is fixed to the lower surface of the lid 4. That is, in the illustrated example, the center roller 9 rotates inside the fixed outer drum 11. The inner peripheral surface of such an outer drum 11 is a second cylindrical surface 13.

[0005] In an annular space 14 between the second cylindrical surface 13 and the first cylindrical surface 10, a plurality of (four in the illustrated example) pivots 15, 15 are partially inserted. doing. These pivots 15 are arranged in parallel with the rotary drive shaft 5, respectively. Further, intermediate rollers 16, 16 are rotatably supported by the radial needle bearings 17, 17 at portions of the respective pivots 15, 15 which are located inside the annular space 14 by radial needle bearings 17, 17. ing. The outer peripheral surface of each of the intermediate rollers 16 is a third cylindrical surface 18 that comes into contact with the first cylindrical surface 10 and the second cylindrical surface 13, respectively. Further, the portions protruding from the annular space 14 at the ends of the pivots 15 and 15 are connected and fixed to a ring-shaped connecting plate 19 serving as a support member. The base end of the output shaft 20, which is the second rotating shaft, is fixedly connected to the center of the connecting plate 19. The output shaft 20 is provided with a pair of ball bearings 2 inside a cylindrical portion 24 provided at the center of a cover 23 fixedly connected to the distal end of the cylindrical wall portion 12 by a plurality of connecting bolts 22.
5 and 25 support it rotatably.

The operation of the friction roller type electric motor with a speed reducer constructed as described above is as follows. When the rotation drive shaft 5 rotates based on the energization of the stator 6,
Based on the friction between the first outer peripheral surface 10 of the center roller 9 and the third cylindrical surfaces 18, 18 of the intermediate rollers 16, these intermediate rollers 16, 16 around the central roller 9. Revolves while rotating. This revolving motion is transmitted to the output shaft 20 via the pivots 15 and 15 and the connecting plate 19, and the output shaft 20 rotates at a lower speed than the rotary drive shaft 5.

In order to secure the transmission efficiency of the friction roller type transmission, in order to prevent slippage between the third cylindrical surfaces 18, 18 and the first and second cylindrical surfaces 10, 13, It is necessary to secure the contact pressure between these cylindrical surfaces 18, 10, 13 together. In order to secure this contact pressure, in the case of the structure shown in FIGS.
6 is inserted into an annular space 14 between the first cylindrical surface 10 and the second cylindrical surface 13. That is, by heating the outer drum 11 provided with the second cylindrical surface 13 and thermally expanding the outer drum 11, the intermediate rollers 16 are expanded in a state where the diameter of the second cylindrical surface 13 is expanded. , 1
6 is inserted into the annular space 14. After the insertion, when the outer drum 11 is cooled and the diameter of the second cylindrical surface 13 is reduced, the cylindrical surfaces 18, 10, 13 are connected to each other of the members 9, 11, Based on the elastic deformation of No. 16, it comes into contact with a sufficiently large pressure.

On the other hand, US Pat. No. 4,709,589 discloses a friction roller type transmission as shown in FIGS. The friction transmission of the second example of this conventional structure comprises an inner half of a center roller 9a in a fixed housing 29 comprising a bottomed cylindrical main body 25 and a lid 26 closing a base end opening of the main body 25. 8 (right half of FIG. 8) is inserted through a through hole 27 formed at a substantially central portion of the lid 26. still,
The through hole 27 is provided at a position slightly deviated from the center of the lid 26. An end of an input shaft 28, which is a first rotation shaft, is fixedly connected to a portion of the center roller 9a that protrudes from the lid 26 at the outer half (the left half in FIG. 8).

Also, three pivots 15a and 15 are provided inside the housing 29 and around the center roller 9a.
b and 15c are arranged in parallel with the center roller 9a, respectively. That is, each of these pivots 15a, 15b, 15
One end of c (the left end in FIG. 8) is supported by the lid 26, and the other end (the right end in FIG. 8) is supported by the connecting plate 19a. Note that these three pivots 15a, 15b, 15
9c, one pivot 15a located at the upper center of FIGS. 9 to 10 has both ends thereof covered by the lid 26 and the connecting plate 19a.
Is press-fitted and fixed in the fitting hole formed in the hole. Therefore, the pivot 15a is not displaced in the housing 29 in the circumferential direction or the diameter direction.

On the other hand, the remaining two pivots 15b and 15c located on the left and right sides of the lower part in FIGS. 9 to 10 have both ends in the circumferential direction of the housing 29 with respect to the lid 26 and the connecting plate 19a. And, it is supported so as to be slightly displaceable in the diameter direction. For this purpose, the lid 26 and the connecting plate 19a
As shown in FIG. 10, the two pivots 15 b, 15 c
The support holes 30, 30 having an inner diameter larger than the outer diameter of the pivot shaft 15 are formed in the respective support holes 30, 30.
Both ends of b and 15c are loosely engaged. A guide roller 32 and wedge rollers 31a and 31b, which are intermediate rollers, are rotatably supported by radial needle bearings 17 around the intermediate portions of the respective pivots 15a, 15b and 15c. The connecting plate 19a is a part of the inner surface of the lid 26 (the surface on the space side where the guide roller 32 and the wedge rollers 31a and 31b are installed, and the right surface in FIG. 8).
2 and the projections 33 protruding from the wedge rollers 31a, 31b.
By 34, it is connected and fixed to the lid 26.

An annular outer drum 11a is rotatably provided inside the housing 29 at a portion surrounding the guide roller 32 and the wedge rollers 31a and 31b. A central portion of the inner peripheral surface of the outer drum 11a is projected inward in the diametrical direction to form a bank-shaped convex portion 35, and the inner peripheral surface of the convex portion 35 is a second cylindrical surface 13a. The second cylindrical surface 13a and the third cylindrical surfaces 18a, 18a, which are the outer peripheral surfaces of the guide roller 32 and the wedge rollers 31a, 31b, can freely contact each other. The outer diameter side end of the connecting bracket 36 is externally fitted and fixed to the outer drum 11a.
6, the inner end of the output shaft 20a is connected and fixed. The output shaft 20a is rotatably inserted through a second through hole 37 formed in the center of the main body 25 constituting the housing 29, and protrudes outside the housing 29.

The outer peripheral surfaces of the guide roller 32 and the wedge rollers 31a and 31b are in contact with the outer peripheral surface of the center roller 9a and the inner peripheral surface of the outer drum 11a. The center of the center roller 9a and the centers of the output shaft 20a and the outer drum 11a are eccentric to each other. That is, as described above, the through hole 2 through which the center roller 9a is inserted
7 is provided at a position slightly shifted from the center of the housing 29, whereas the second through hole 37 through which the output shaft 20 a is inserted is provided at the center of the housing 29. The output shaft 20a rotatably supported inside the second through hole 37 and the outer drum 11a are concentric with each other. Therefore, the center roller 9a and the outer drum 1
The output shaft 1a and the output shaft 20a are eccentric from each other by the amount of deviation δ (see FIG. 8) of the through hole 27 from the center of the housing 29. The guide roller exists between the first cylindrical surface 10a which is the outer peripheral surface of the center roller 9a and the second cylindrical surface 13a which is the inner peripheral surface of the convex portion 35 formed on the outer drum 11a. 32 and wedge roller 3
The width dimension of the annular space 14a provided with 1a, 31b is
By the amount corresponding to the eccentric amount of δ, the eccentricity is not uniform in the circumferential direction.

As described above, the outer diameters of the guide roller 32 and the wedge rollers 31a, 31b are made different by the amount of the width of the annular space 14a being made uneven in the circumferential direction. That is, the center roller 9 with respect to the outer drum 11a
The wedge rollers 31a and 31b located on the side where "a" is eccentric (the lower side in FIGS. 8 to 10) have the same diameter and have a relatively small diameter. On the other hand, the diameter of the guide roller 32 located on the opposite side (upper side in FIGS. 8 to 10) of the center roller 9a to the outer drum 11a is eccentric to that of the two wedge rollers 31a and 31b. I'm making it big. The third cylindrical surfaces 18a, 18a, 1b, which are the outer peripheral surfaces of the three guide rollers 32 and wedge rollers 31a, 31b, respectively, are intermediate rollers.
8a is in contact with the first and second cylindrical surfaces 10a and 13a.

The above-mentioned 1 is an intermediate roller.
Guide rollers 32 and two wedge rollers 31
a, 31b, the pivot 1 supporting the guide roller 32
5a is fixed in the housing 29 as described above. On the other hand, the pivots 15b and 15c supporting the wedge rollers 31a and 31b freely support a slight displacement in the circumferential direction and the diametric direction in the housing 29 as described above. Therefore, the wedge rollers 31a and 31b are also slightly displaceable in the circumferential direction and the diametrical direction in the housing 29. The wedge rollers 31a, 31b are supported by elastic members such as compression coil springs 39, 39 mounted in the cylinder holes 38, 38 of the lid 26.
5c is rotatably supported on each of these pivots 15b, 15c.
It is elastically lightly pressed in order to move it toward the narrow portion a.

In the case of the friction roller type transmission of the second example having the conventional structure configured as described above, the rotation of the center roller 9a connected to the input shaft 28 is caused by the rotation of the first roller on the outer peripheral surface of the center roller 9a. A cylindrical surface 10a and a third cylindrical surface 1 which is an outer peripheral surface of the guide roller 32 and the wedge rollers 31a and 31b.
8a, 18a, each inner diameter side contact portion 40,
The light is transmitted to the guide roller 32 and the wedge rollers 31a and 31b through the reference numeral 40. Further, the rotation of the guide roller 32 and the wedge rollers 31a, 31b is caused by the rotation of the third cylindrical surfaces 18a, 18a and the outer drum 11
The power is transmitted to the outer drum 11a via the outer diameter side abutting portions 41, 41, which are abutting portions with the second cylindrical surface 13a provided on the inner peripheral surface of a. Then, the output shaft 20a fixedly connected to the outer drum 11a rotates.

When the center roller 9a rotates clockwise (or counterclockwise) in FIGS. 9 to 10, and the outer drum 11a also rotates counterclockwise (or clockwise), respectively, the right pivot in FIGS. 15b (or left pivot 15c)
Roller 31a (or 31) rotatably supported
b) in the annular space 14a existing between the first and second cylindrical surfaces 10a and 13a,
Move toward a narrow portion (the lower central portion in FIGS. 9 to 10). As a result, the wedge roller 31a (or 31b) rotatably supported on the pivot 15b (or 15c).
The third cylindrical surface 18a, which is the outer peripheral surface of, strongly presses the first cylindrical surface 10a and the second cylindrical surface 13a. The inner diameter side contact portion 40, which is a contact portion between the third cylindrical surface 18a of the wedge roller 31a (or 31b) and the first cylindrical surface 10a, and the wedge roller 31a (or 31b). The outer diameter side contact portion 4 which is a contact portion between the third cylindrical surface 18a and the second cylindrical surface 13a.
The contact pressure of No. 1 increases.

The one wedge roller 31a (or 3)
When the contact pressure between the inner and outer diameter contact portions 40 and 41 with respect to 1b) increases, the center roller 9a and the outer drum 1
At least one of the members 1a and 1a is slightly displaced in the diametrical direction based on an assembling gap or elastic deformation. As a result, the third cylindrical surfaces 18a, 18a, which are the outer peripheral surfaces of the guide rollers 32 and the wedge rollers 31b (or 31a), which are the remaining two intermediate rollers.
And a first cylindrical surface 10 which is an outer peripheral surface of the center roller 9a.
a, the two inner diameter side contact portions 40, 40,
And the third cylindrical surfaces 18a, 18a, 1b which are the outer peripheral surfaces of these wedge rollers 31b (or 31a) and guide rollers 32
8a and the second cylindrical surface 1 which is the inner peripheral surface of the outer drum 11a
Two outer diameter side contact portions 41, 41 which are contact portions with 3a
Contact pressure increases.

The force for moving the wedge roller 31a (or 31b) rotatably supported by the one pivot 15b in the annular space 14a toward the narrow portion of the annular space 14a is the force described above. It changes according to the magnitude of the torque transmitted from the center roller 9a to the outer drum 11a. That is, as the driving torque of the center roller 9a increases, the force for moving the wedge roller 31a (or 31b) toward the narrow portion of the annular space 14a increases. And, as this force increases, the contact pressure of the inner diameter side and outer diameter side contact portions 40 and 41 increases. Conversely, when the driving torque is small, the contact pressures of the inner and outer contact portions 40 and 41 are small.

In the case of each friction roller type transmission configured and operated as described above, oil such as grease or traction oil is put in the housings 29 and 29a, and the first and second cylindrical surfaces 10, 10a and 13 are filled. , 13a and a third cylindrical surface 18,
Power transmission to and from the motor 18a is performed via this oil. These cylindrical surfaces 10, 10a, 13, 13a, 1
Since the oil film existing between 8, 8a is extremely thin, the above-described power transmission can be performed based on a large shearing force acting on the oil film. In addition, this oil film transmits power at the same time
Each of the cylindrical surfaces 10, 10a, 13, 13a, 18, 18
a is prevented from coming into direct contact with each other, thereby preventing significant wear due to metal contact.

[0020]

When the friction roller type transmission as described above is operated at a high speed, the rotation of the center rollers 9, 9a, the intermediate rollers 16, 16, the wedge rollers 31a, 31b, the guide rollers Due to the centrifugal force based on the rotation and revolution of 32, the oil put in the housings 29 and 29a is blown down to the outer diameter portions of the housings 29 and 29a. For this reason, the oil present near the inner diameter side contact portions 40, 40, which are the contact portions between the first cylindrical surfaces 10, 10a and the third cylindrical surfaces 18, 18a, tends to be insufficient. As a result, metal contact easily occurs at these inner diameter side contact portions 40, 40, and if it occurs, damage to the first and third cylindrical surfaces 10, 10a, 18, 18a such as flaking is caused. Is generated, and the durability of the friction roller type transmission is impaired. The friction roller type transmission of the present invention has been invented to solve the above-mentioned problems.

[0021]

In each of the friction roller type transmissions of the present invention, like the above-mentioned conventional friction roller type transmission, a first rotating shaft and one end of the first rotating shaft are provided. A central roller whose outer peripheral surface is a first cylindrical surface, which is fixed concentrically with the first rotating shaft, and which is disposed around the central roller so as to be rotatable relative to the central roller, and whose inner peripheral surface is An outer drum that is a second cylindrical surface, each of which is disposed in parallel with the first rotation axis, and a part of each is disposed in an annular space between the second cylindrical surface and the first cylindrical surface. The inserted plurality of pivots, and a part of each of the pivots, which is located inside the annular space, is rotatably supported with respect to each of the pivots. A plurality of intermediate rollers having a third cylindrical surface in contact with the second cylindrical surface A supporting member that supports a portion protruding from the annular space at an end of each of the pivots, and a second rotating shaft having one end coupled and fixed to one of the supporting member and the outer drum. .

In particular, in the friction roller type transmission of the present invention, in the friction roller type transmission according to the first aspect, at least one of the intermediate rollers has at least one intermediate roller on the outer peripheral surface thereof. A recess capable of holding lubricating oil is provided.

Further, in the friction roller type transmission according to the present invention, a holding hole capable of holding lubricating oil is provided inside the center roller, and the holding hole and an outer peripheral surface of the center roller are provided. And a supply hole for supplying the lubricating oil is provided on the outer peripheral surface.

[0024]

According to the friction roller type transmission of the present invention configured as described above, a sufficient amount of oil can be present at the contact portion between the first cylindrical surface and the third cylindrical surface, The occurrence of metal contact at this contact portion can be prevented.

[0025]

1 to 3 show a first embodiment of the present invention corresponding to claim 1. FIG. The feature of the present invention resides in the structure and operation of a portion that rotatably supports an intermediate roller around a plurality of pivots. Since the structure and operation of the other parts are basically the same as those of the second example of the conventional structure shown in FIGS. 8 to 10 described above, the same parts are denoted by the same reference numerals and redundant description is omitted. Or, for simplicity, the following description is based on the features of the present invention and FIGS.
The following description focuses on the differences from the second example of the conventional structure shown in FIG.

One guide roller 32 and two wedge rollers 31a,
Deep groove-type outer ring raceways 42, 42 are formed on the inner peripheral surface of the intermediate portion with 1b. On the other hand, each axis 15a, 15
b, 15c, the outer ring raceways 42, 42
, Deep groove type inner ring raceways 43 are formed. A plurality of balls 44, 44 are provided between the outer raceways 42, 42 and the inner raceways 43, 43, respectively, in such a manner as to freely roll. Each of these balls 4
4 and 44 are rotatably held by retainers 45 and 45, respectively. Therefore, each of the rollers 32, 31
The a and 31b are rotatably supported on the pivots 15a, 15b and 15c by the deep groove type ball bearings 46 and 46 in a state where displacement in the thrust direction is prevented.

Preferably, a desired preload is applied to each of the balls 44, 44 so that no positive internal gap is provided in each of the ball bearings 46, 46 (a negative internal gap is provided). The rattling of the bearings 46, 46 is eliminated. The cages 45, 45 are provided to prevent the rolling surfaces of the adjacent balls 44, 44 from rubbing against each other, and to prevent the rotational resistance of the ball bearings 46, 46 from increasing. However, when the radial load or thrust load applied to these ball bearings 46, 46 is large, the retainers 45, 45 are omitted and the outer raceways 42, 42 and the inner raceways 43, 4 are omitted.
The number of the balls 44 provided between the ball bearings 3 and 3 can be increased to provide a so-called full ball type ball bearing. In this case, the work of providing the balls 44, 44 between the outer raceways 42, 42 and the inner raceways 43, 43 is performed by shrink fit or cold fit.

Further, in the case of the friction roller type transmission of the present invention, spiral grooves 49, 49 are formed on the outer peripheral surfaces of the one guide roller 32 and the two wedge rollers 31a, 31b. The spiral grooves 49, 49 are formed as concave portions capable of holding lubricating oil. Such spiral grooves 49, 49 are formed by performing cutting such as lathing on the outer peripheral surfaces of the rollers 32, 31a, 31b. The burrs formed at the opening edges of the spiral grooves 49, 49 accompanying the cutting are removed by liquid honing or the like.

Although not related to the gist of the present invention, in the illustrated example, the coupling structure between the outer drum 11b and the output shaft 20b as the second rotating shaft is a conventional structure shown in FIGS. Is different from the second example. That is, in the illustrated example, the opening of one end (the left end in FIG. 1) of the outer drum 11b is closed by the disk portion 47, and the center of the outer surface (the left side surface in FIG. 1) of the disk portion 47 is connected to the output shaft 20b. Is fixed concentrically with the outer drum 11b.
Further, in the illustrated example, a center roller 9b provided integrally with the output shaft 20b and the input shaft 28a, which is the first rotating shaft, at the tip (left end in FIG. 1) of the input shaft 28a is attached to the housing 29a. And deep groove ball bearings 48, 4
8 rotatably supported.

According to the friction roller type transmission of the present invention constructed as described above, the first cylindrical surface 10a provided on the outer peripheral surface of the center roller 9b and the one guide rollers 32 and 2 are provided.
A sufficient amount of oil can be made to exist in the vicinity of the contact portions with the third cylindrical surfaces 18a, 18a provided on the outer peripheral surfaces of the wedge rollers 31a, 31b. That is, during operation of the friction roller type transmission, the center roller 9a and the guide roller 3
Due to the centrifugal force based on the rotation of the housing 2 and the wedge rollers 31a and 31b, the oil put in the housing 29a is dropped off to the outer diameter portion of the housing 29a.

A portion of the oil that has thus fallen to the outer diameter portion of the housing 29a flows down in the housing 29a and accumulates inside the lower portion of the housing 29a. The position of the lower inner side varies depending on the installation direction of the friction roller type transmission, but in any case, a part of the outer drum 11b passes through the oil accumulated in the lower inner side of the housing 29 based on the rotational motion. A large amount of oil is made to adhere to the second cylindrical surface 13b which is the inner peripheral surface of the outer drum 11b. The oil adhering to the second cylindrical surface 13b in this manner is applied to the third cylindrical surface 18a, which contacts the second cylindrical surface 13b.
It is taken into spiral grooves 49, 49 formed on the outer peripheral surface of the rollers 32, 31a, 31b, which are 18a. Then, the oil taken in the spiral grooves 49, 49 on the outer peripheral surfaces of the rollers 32, 31a, 31b in this manner is retained even after the outer drum 11b escapes from the oil accumulated inside the lower portion of the housing 29a. , These rollers 32, 31
The third cylindrical surfaces 18a, 18a provided on the outer peripheral surface of each of the rollers 32, 31a, 31b and the second cylinder provided on the inner peripheral surface of the outer drum 11b by centrifugal force based on the rotation of the a, 31b. It is sent to the contact portion with the surface 13a.
For this reason, each of the inner diameter side contact portions 40, 4, which are contact portions between the third cylindrical surfaces 18 a, 18 a and the second cylindrical surface 13 a, are provided.
Since there is always an appropriate amount of oil at zero, it is possible to prevent metal contact between these inner contact portions 40, 40.

The spiral directions of the spiral grooves 49, 49 are as follows.
The guide roller 32 and each wedge roller 31a, 3
Based on the rotation of 1b, the oil existing on the opening side of the outer drum 11b (on the inner surface side of the lid 26 of the housing 29a and on the right side in FIGS. 1 and 3) is formed in a direction of being scraped into the spiral grooves 49, 49. Things are preferred. For example, if the guide roller 32 and the wedge rollers 31a, 31b are controlled to rotate in a direction in which the front surface shown in FIG. 3 is displaced upward from the bottom in FIG. The oil present on the opening side can be efficiently spread over the entire width of the third cylindrical surfaces 18a, 18a. That is, if the directions of the spiral grooves 49, 49 are regulated as described above, the mist-like oil floating in the housing 29a is taken in and used for lubrication of the respective inner diameter side contact portions 40, 40. Can be.

In the illustrated example, the outer raceways 42, 42 formed on the inner peripheral surface of the intermediate portion between the one guide roller 32 and the two wedge rollers 31a, 31b, and the respective pivots 15a, 15b, 15c Inner raceways 43, 43 formed on the outer peripheral surface of the intermediate portion of the vehicle, and a plurality of balls 44 provided between the inner raceways 43, 43 and the outer raceways 42, 42;
44 form deep groove ball bearings 46, 46. Then, these ball bearings 46, 46 are provided around the respective rollers 32, 3 around the respective pivots 15a, 15b, 15c.
1a and 31b are rotatably supported.

Each of the deep groove ball bearings 46 supports not only a radial load but also a thrust load. Because of this,
Even if a thrust load is applied to the rollers 32, 31a, 31b, the rollers 32, 31a, 31b can be prevented from being displaced in the thrust direction. Therefore, both ends in the axial direction of the rollers 32, 31a and 31b are opposite to each other, and the inner surface (the left surface in FIG. 1) or the connecting plate 19a of the lid 26 constituting the housing 29a.
Does not rub against the inner side (right side in FIG. 1). Incidentally, both ends of the rollers 32, 31a, 31b in the axial direction and the cover 2
It is not particularly necessary to provide a thrust bearing between the inner surface of 6 and the inner surface of the connecting plate 19a. However, the gap between these opposing surfaces is particularly small, and when a large thrust load is applied, if there is a possibility that these two surfaces may rub, if desired, polyamide resin, polytetrafluoroethylene resin, It is also possible to provide a thrust slide bearing formed of a resin having a low coefficient of friction, such as a polyacetal resin, so as to be thin.

In the above embodiment, two of the three intermediate rollers are used as wedge rollers 31a and 31b,
The case where the present invention is applied to a structure in which the remaining one intermediate roller is the guide roller 32 has been described. With such a structure, even when the input shaft 28a and the output shaft 20b rotate in any direction, the contact pressure of each inner diameter side contact portion 40, 40 and each outer diameter side contact portion 41, 41 can be secured. . However, the present invention is not limited to such a structure, and can be applied to various friction roller type transmissions. For example, if the rotation directions of the input shaft and the output shaft are always constant, a structure in which one of the three intermediate rollers is a wedge roller and the remaining two intermediate rollers are guide rollers is sufficient. The present invention can be applied to such a structure. Also, as in the first example of the conventional structure shown in FIGS.
The present invention can also be applied to a structure in which 1 is concentrically arranged. Further, the present invention can be applied to a structure in which the input shaft and the output shaft are reversed from the illustrated example and used as a gearbox.

Next, FIG. 4 shows a second embodiment of the present invention, which also corresponds to claim 1. In the case of this example, the guide roller 32 (or the wedge roller 31)
a, 31b), a large number of spherical concave portions 50, 50 are formed on the outer peripheral surface, and oil can be held in each of the concave portions 50, 50. Such concave portions 50, 50
Formed on the outer peripheral surface of 2, 31a, 31b by forging. After forging, these rollers 32, 31a, 31b
By performing a grinding process on the outer peripheral surface of each of the concave portions 50,
Eliminate the floating around the periphery of the roller 50
The outer peripheral surface of 2, 31a, 31b is a third cylindrical surface 18a having a desired shape.

In the case of the structure of the present embodiment constructed as described above, the oil taken into each of the concave portions 50, 50 with the rotation of each of the rollers 32, 31a, 31b is applied to each of these rollers 3.
By centrifugal force based on the rotation of 2, 31a, 31b,
The rollers 32, 31a, and 31b are fed into a contact portion between a third cylindrical surface 18a provided on the outer peripheral surface and a second cylindrical surface 13a (FIGS. 1 and 2) provided on the inner peripheral surface of the outer drum 11b. . For this reason, each inner diameter side contact portion 40 (FIG. 1 to FIG. 1) which is a contact portion between the third cylindrical surface 18a and the second cylindrical surface 13a.
In (2), an appropriate amount of oil is always present to prevent the occurrence of metal contact at each of the inner diameter side contact portions 40. The configuration and operation of the other parts are the same as in the case of the first example described above.

Next, FIG. 5 shows a third embodiment of the present invention corresponding to claim 2. In the case of this example, a holding hole 51 capable of holding grease, which is a kind of lubricating oil, is provided inside the center roller 9c. One or more supply holes 52 are provided between the inner peripheral surface of the holding hole 51 and the outer peripheral surface of the center roller 9c. The supply hole 52 is a part of the first cylindrical surface 10 (10a) provided on the outer peripheral surface of the center roller 9c, and is formed by the intermediate roller 16 (or the guide roller 32 or the wedge rollers 31a, 31a).
An opening is provided at a position slightly deviated in the axial direction from a portion facing the third cylindrical surface 18 (18a) provided on the outer peripheral surface of b).

In the case of this embodiment, at the time of assembling the friction roller type transmission, the holding hole 51 is filled with grease having a desired viscosity from the opening on the tip end side of the center roller 9c. . When the center roller 9c rotates during the operation of the friction roller type transmission, the grease filled in the holding hole 51 is separated from the supply holes 52, 5 by the centrifugal force.
2 to the first cylindrical surface 10 (10a), and gradually to the third cylindrical surface 18 (18a) provided on the outer peripheral surface of the intermediate roller 16 (or the guide roller 32 or the wedge rollers 31a, 31b). Adhere to. For this reason, an appropriate amount of oil always exists in each inner diameter side contact portion 40 which is a contact portion between the third cylindrical surface 18 (18a) and the second cylindrical surface 13 (13a). The occurrence of metal contact at the inner diameter side contact portion 40 can be prevented.

[0040]

Since the present invention is constructed and operates as described above, it is possible to effectively prevent the occurrence of damage such as premature abrasion on each component, and to improve the durability and reliability of the friction roller type transmission. Can be improved.

[Brief description of the drawings]

FIG. 1A shows a first example of an embodiment of the present invention,
-A sectional drawing.

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

FIG. 3 is a view of a guide roller or a wedge roller taken out and viewed from the same direction as FIG. 1;

FIG. 4 is a view similar to FIG. 3, showing a second example of the embodiment of the present invention;

FIG. 5 is an essential part cross-sectional view showing a third example of the embodiment of the present invention.

FIG. 6 is a sectional view of a friction roller type electric motor with a speed reducer, showing a first example of a conventional structure.

7 is a sectional view taken along the line CC of FIG. 6, showing only a friction roller type speed reducer.

FIG. 8 is a sectional view showing a second example of the conventional structure.

FIG. 9 is a sectional view taken along the line DD in FIG. 8;

FIG. 10 is a sectional view taken along the line EE in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electric motor 2 Motor case 3 Case main body 4 Lid 5 Rotation drive shaft 6 Stator 7 Rotor 8 Friction roller type reduction gear 9, 9a, 9b, 9c Center roller 10, 10a First cylindrical surface 11, 11a, 11b Outer drum 12 cylindrical wall portion 13, 13a second cylindrical surface 14, 14a annular space 15, 15a, 15b, 15c pivot 16 intermediate roller 17 radial needle bearing 18, 18a third cylindrical surface 19, 19a connecting plate 20, 20a, 20b Output shaft 21 Fixing bolt 22 Connection bolt 23 Cover 24 Cylindrical part 25 Main body 26 Lid 27 Through hole 28, 28a Input shaft 29, 29a Housing 30 Support hole 31a, 31b Wedge roller 32 Guide roller 33 Projection 34 Connection bolt 35 Projection 36 Connecting bracket 37 Second through hole 38 Cylinder hole 3 9 Compression Coil Spring 40 Inner Diameter Contact Section 41 Outer Diameter Contact Section 42 Outer Ring Track 43 Inner Ring Track 44 Ball 45 Cage 46 Ball Bearing 47 Disk Section 48 Ball Bearing 49 Spiral Groove 50 Recess 51 Holding Hole 52 Supply Hole

Claims (2)

[Claims] A first rotating shaft, a center roller fixed to one end of the first rotating shaft concentrically with the first rotating shaft and having an outer peripheral surface as a first cylindrical surface; An outer drum whose inner peripheral surface is a second cylindrical surface, which is disposed around the center roller so as to be rotatable relative to the center roller, each is disposed parallel to the first rotation axis, and a part of each is disposed. A plurality of pivots inserted into the annular space between the second cylindrical surface and the first cylindrical surface, and a part of each of these pivots located inside the annular space, A plurality of intermediate rollers which are rotatably supported with respect to the pivot, and each outer peripheral surface of which is a third cylindrical surface abutting on the first cylindrical surface and the second cylindrical surface, and an end of each of the pivots; A support member that supports a portion protruding from the annular space; And a second rotating shaft having one end coupled and fixed to one of the drums, wherein at least one of the intermediate rollers is provided.
A friction roller type transmission, wherein a concave portion capable of holding lubricating oil is provided on an outer peripheral surface of each of the intermediate rollers. 2. A first rotating shaft, a center roller fixed to one end of the first rotating shaft concentrically with the first rotating shaft and having an outer peripheral surface as a first cylindrical surface; An outer drum whose inner peripheral surface is a second cylindrical surface, which is disposed around the center roller so as to be rotatable relative to the center roller, each is disposed parallel to the first rotation axis, and a part of each is disposed. A plurality of pivots inserted into the annular space between the second cylindrical surface and the first cylindrical surface, and a part of each of these pivots located inside the annular space, A plurality of intermediate rollers which are rotatably supported with respect to the pivot, and each outer peripheral surface of which is a third cylindrical surface abutting on the first cylindrical surface and the second cylindrical surface, and an end of each of the pivots; A support member that supports a portion protruding from the annular space; In a friction roller type transmission having a second rotating shaft having one end coupled and fixed to one of the drums, a holding hole capable of holding lubricating oil is provided inside the center roller, A friction roller type transmission, wherein the holding hole is communicated with the outer peripheral surface of the center roller, and a supply hole for supplying the lubricating oil is provided on the outer peripheral surface.