JP2002061727A - Differential frictoin roller reduction gear - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a quiet and compact differential friction roller reduction gear with a high reduction ratio, eliminating the lost of power transmitting ability even if a rolling bearing is worn. SOLUTION: The differential friction roller reduction gear comprises a casing for supporting an input shaft and an output shaft in a concentric and rotatable manner, the input shaft provided with an eccentric shaft being parallel to a center shaft thereof and having a width in an eccentric direction smaller than that in a perpendicular direction, a friction roller having a friction roller surface on the outer periphery and a plurality of through-holes opened in the side face, the rolling bearing provided in a space to the eccentric shaft at the center of the friction roller, a friction inner roller fixed into the casing, force-out means provided between the eccentric shaft and the rolling bearing for putting the friction roller in force contact with the friction inner roller, and an output shaft integrated with a disc on which a transmission shaft is fixed for transmitting torque from the friction roller with the engagement of the through-holes. Therefore, it has quite operation and long power transmitting performance with a high reduction ratio.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanical speed reducer, and more particularly, to a small, lightweight and quiet differential friction roller speed reducer having a large reduction ratio.

[0002]

2. Description of the Related Art Conventionally, a differential gear reducer using gears has been used as a compact mechanical speed reducer. However, since the gear reducer generates noise, it is used in a place where a quiet environment is required. Use was restricted.

[0003] As a speed reducer meeting such conditions, a planetary roller speed reducer has been provided in which a sun roller is directly connected to an input shaft, a plurality of planetary rollers are arranged on the outer periphery thereof, and the outside of the planetary roller is fastened by a fixed inner ring. However, the planetary roller speed reducer has a limitation in the reduction ratio and the transmission torque, and a high reduction ratio in one stage cannot be expected. To obtain a high reduction ratio and an appropriate transmission torque, a two-stage, three-stage reduction mechanism is required. Required, and there were difficulties in terms of cost.

[0004] The differential friction roller reduction device can obtain a high reduction ratio in one stage, and an example of a conventional one is disclosed in JP-A-53-72961. In this differential friction roller reduction device, an output planetary roller (friction roller) is rotatably fitted to an eccentric shaft provided on an input shaft via a rolling bearing, and an outer peripheral surface of the output planetary roller is shrink-fitted to a casing. The inner peripheral surface of the outer wheel (friction inner roller) comes in contact with the pressurized state, and the frictional force and the rotational force transmitted from the eccentric shaft to the planetary roller are combined, and the output torque is the power from the output shaft. Is taken out.

The reduction ratio 1 / R is 1 / R = (Do−D
r) / Dr (Do: outer raceway diameter of the outer wheel, Dr: output planetary roller diameter), and a larger reduction ratio is obtained as the output planetary roller diameter approaches the outer raceway diameter.

[0006]

As described above, in a planetary roller reduction device in which a plurality of planetary rollers are arranged at equal angle angles on a sun roller, it is difficult to increase the reduction ratio in a single stage, and a high reduction ratio is required. It is necessary to install two-stage and three-stage deceleration mechanisms to obtain, the device becomes large, the number of parts increases,
High cost.

A conventional differential friction roller reduction device using a large-diameter output planetary roller and an outer wheel slightly larger in inner diameter than the output planetary roller, as disclosed in Japanese Patent Application Laid-Open No. 53-72961, An output planetary roller is fitted to the eccentric shaft provided on the input shaft via a rolling bearing, and the outer peripheral surface of the output planetary roller is pressed against the inner peripheral surface of the outer wheel fixed to the casing, and power is transmitted by the frictional force. In addition, by assembling by shrink fitting or the like, members having high rigidity are mechanically restrained and brought into contact with each other to obtain the pressure contact force.

However, the rolling bearing is rotated by an eccentric shaft rotating at a high speed, and at the same time, the pressure contact force of an output planetary roller pressed against the outer ring is applied. Therefore, the rolling elements (rollers or balls) of the rolling bearing gradually wear. I do.

[0009] The friction transmission mechanism of the conventional differential friction roller reduction device described above is constituted by mechanical restraint and contact between members having high rigidity. The roller is used for the pressure contact force between the outer ring (the friction inner roller) and the outer wheel (friction inner roller). Therefore, as described above, if even a small amount of wear occurs on the rolling element of the rolling bearing, the pressure contact force is reduced, and the power transmission capability is lost. As a result, there were problems in durability and practicality.

According to the present invention, the eccentric shaft is rotated at a high speed,
It is an object of the present invention to provide a quiet and compact differential friction roller reduction device with a high reduction ratio that has a large range in which a rolling bearing that receives a load of an output planetary roller (friction roller) does not lose its power transmission capability even when worn. Is what you do.

[0011]

Means for Solving the Problems (1) The present invention has been made to solve the above-mentioned problems, and the
The input shaft provided with an eccentric shaft which is rotatably supported by a casing via a bearing and has an axis width in the eccentric direction parallel to the rotation center axis and smaller than an axis width perpendicular to the eccentric direction,
A disk-shaped friction roller having a friction roller surface formed on an outer periphery thereof and a plurality of through holes in the input axis direction formed at equal angles on the same pitch circle on the side surface and having a through hole in the center; A rolling bearing provided between the eccentric shaft and a press-fitted through-hole; a friction inner roller fixed in the casing at a position concentric with the input shaft and surrounding the friction roller; A pressurizing means provided between a shaft and the rolling bearing to press out the friction roller in an eccentric direction through the same rolling bearing to press the friction roller against the friction inner roller, and engage with each of the plurality of through holes. A disc in which a plurality of transmission shafts for transmitting torque from a friction roller are fixed at equiangular positions on a pitch circle having the same radius as the through-hole, and the disc is integrally formed with the casing through a bearing via a bearing. Supported concentrically with the input shaft Wherein providing differential friction roller reduction apparatus characterized by comprising an output shaft that.

According to the first means, when the friction roller externally fitted to the eccentric shaft of the input shaft via the rolling bearing by the rotation of the input shaft via the rolling bearing is eccentrically rotated by the rotation of the input shaft, the operation of the press-out means is performed. The friction roller surface is securely pressed against the inner surface of the friction inner roller fixed in the casing and rolls, quietly without generating noise, the friction force between the friction roller and the friction inner roller, and the input. The differential reduction rotation and the torque of the high reduction ratio of the friction roller generated by the force acting on the shaft center of the eccentric shaft due to the shaft torque are transmitted to the output shaft through the transmission shaft, and the rolling bearing of the rolling bearing is Even if the rolling elements wear, the surface pressure between the friction roller and the friction inner roller can be maintained, and the power transmission performance can be maintained for a long time.

(2) As a second means, in the differential friction roller reduction device of the first means, the eccentric shaft has an elliptical cross section, and the side surface on the side of the projecting side due to eccentricity when the rolling bearing is externally fitted. Alternatively, a gap is formed between the side surface on the retracting side and the inner surface of the same rolling bearing so that the same rolling bearing can be moved in the eccentric direction, and a quadrangular concave hole is provided on the side surface on the same extending side. Is a leaf spring pressurized and fitted between the inner surface of the rolling bearing and the rectangular recess.

According to the second means, in addition to the action of the first means, when the friction roller rotates eccentrically by the rotation of the input shaft, the inner surface of the rolling bearing and the rectangular recessed hole in the side surface of the eccentric shaft are formed. The pressure of the leaf spring pressurized in the gap is the force by which the friction roller presses the friction inner roller, and even if the rolling bearings are worn, the range in which the friction force between the rollers works reliably is large. Dynamic deceleration rotation and high transmission torque can be maintained.

(3) As a third means, in the differential friction roller reduction device of the first means, the eccentric shaft has a rectangular cross section having a parallel plane along an eccentric direction, and slides with the parallel plane. A square tube having a square hole which is capable of forming a gap between the side surface on the projecting side or the side surface on the retracted side due to the eccentricity of the eccentric shaft is externally fitted, and the square hole tube is pressurized inside the rolling bearing. A differential friction roller deceleration mechanism, wherein the pressing means is a leaf spring which is pressurized and fitted in a gap between the inner surface of the square hole cylinder and a side surface of the eccentric shaft on the protruding side. Provide equipment.

According to the third means, in addition to the action of the first means, when the friction roller rotates eccentrically by the rotation of the input shaft, the gap between the inner surface of the rectangular cylinder and the side surface of the eccentric shaft is pressurized. The pressure of the leaf spring becomes the force that the friction roller presses against the inner friction roller, and even if the rolling bearings are worn, the range in which the friction force between the rollers works reliably is large, and the differential reduction rotation at a high reduction ratio is high. It can hold the transmission torque.

(4) As a fourth means, in the differential friction roller reduction device of the first means or the second means, the eccentric shafts of the input shafts have the same eccentric dimensions and are sequentially 180 degrees in the axial direction of the input shafts. Change the eccentric phase angle by degrees and set the axial length to 1
Three sets of eccentric shafts provided in series at a ratio of two to one, wherein the friction roller, the rolling bearing and the pressing means are combined with each of the three sets of eccentric shafts and transmit the width thereof. Three sets of side-contacting friction rollers having the same outer diameter, three sets of side-contacting rolling bearings, and three sets of side-contacting pressing-out means in which the pressing force is set to a ratio of 1: 2: 1 in the above-mentioned order. The roller is a wide friction inner roller commonly circumscribing the three sets of friction rollers having the same outer diameter that are in contact with the side, and the output shaft is different from the three sets of friction rollers that are in contact with each other through the common transmission shaft. There is provided a differential friction roller reduction device characterized in that it is configured to take out dynamic deceleration rotation.

According to the fourth means, in addition to the action of the first means or the second means, the power transmission capacity is doubled.
Since the pressing force against the friction roller acts in opposition, the bending moment of the input shaft is balanced in the input shaft, and the load on the bearing of the input shaft is remarkably reduced. At the same time, the eccentric rotating weight is balanced and the rotating performance is improved. .

(5) As a fifth means, in the differential friction roller reduction device of the third means, the eccentric shaft of the input shaft has the same eccentric dimension and is 18 in the axial direction of the input shaft in order.
The eccentric phase angle is changed by 0 degree, and the length in the axial direction is 1: 2: 1.
And the friction roller, the rolling bearing, and the pressing means are combined with each of the three sets of eccentric shafts and transmit the pressing force transmitted with the width thereof. Side-contact 3 with the ratio of 1: 2: 1 in the above order
A pair of friction rollers having the same outer diameter, three sets of rolling bearings in contact with each other, and three sets of pressing means that are in contact with each other, wherein the inner friction roller is common to the three sets of friction rollers having the same outer diameter in contact with each other. A differential friction roller, wherein the output shaft is configured to take out differential deceleration rotation from the three sets of friction rollers which are in contact with each other through the common transmission shaft. A roller reduction device is provided.

According to the fifth means, in addition to the action of the third means, the power transmission capacity is doubled, and the pressing force against the friction roller acts in opposition, so that the bending moment of the input shaft is reduced. As a result, the load on the bearing of the input shaft is remarkably reduced, and at the same time, the eccentric rotation weight is balanced and the rotation performance is improved.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A differential friction roller reduction device according to a first embodiment of the present invention will be described with reference to FIGS. 1 is a side sectional view of the friction roller reduction device of the present embodiment, FIG. 2 is a front sectional view taken along the line AA in FIG. 1, and FIG.
FIG. 4 is a detailed view of the central portion of FIG. 2, and FIG. 4 is an explanatory view of the state of engagement between the eccentric shaft and the leaf spring of FIG.

In FIG. 1, a casing lid 2 is attached to a casing 1, and in a combined state thereof, an input shaft 3 and an output shaft 4 are rotatably supported concentrically. Casing 1
A friction inner roller 8 is press-fitted concentrically with the input shaft 3 and fastened by the casing lid 2, and its rotation direction is fixed to the casing 1.

Bearings 18 are mounted on the output shaft 4 by bearing nuts 21, and the output shaft 4 is supported by the casing lid 2 via the bearings 18. The bearings 18 are fixed to the casing lid 2 in the axial direction by a bearing cover 22.

The input shaft 3 is supported by the casing 1 via a bearing 13 and a separator 15, and is supported at a center hole of the output shaft 4 via a bearing 16 and a separator 17. The bearing 13 is axially fixed to the casing 1 by a bearing cover 14.

The input shaft 3 has an eccentric shaft 3a between the barrels 15 and 17, which is parallel to the center axis of rotation and eccentric by a distance e. The eccentric shaft 3a has its eccentric shaft width slightly larger than the shaft width perpendicular to the eccentric direction so that a fixed gap s1 can be provided between the inner surface of the rolling bearing 5 fitted on the extended side and the retracted side due to eccentricity. It has a reduced elliptical cross section.

For this reason, the rolling bearing 5 can move in the eccentric direction by the gap s1 in a state where the rolling bearing 5 is fitted around the outer periphery of the eccentric shaft 3a.

Further, a quadrangular concave hole 3b is provided on the side surface of the eccentric shaft 3a on the side of the overhang due to the eccentricity.
A leaf spring 6 made of a plurality of bent steel plates is fitted in the inside.

A disk-shaped friction roller 7 is fixed to the outer periphery of the rolling bearing 5 by press-fitting in a through hole provided at the center thereof, and the outer periphery of the friction roller 7 forms a friction roller surface. 4 is fitted into the rolling bearing 5 when the friction roller 7 is not combined with the friction inner roller 8 with the eccentric shaft 3a and the pressurized leaf spring 6 shown in FIG. Indicates a state of failure. In this state,
The side surface 3 c on the retracted side due to the eccentricity of the eccentric shaft 3 a is in contact with the rolling bearing 5.

However, when the friction roller 7 is combined with the friction inner roller 8 in the casing 1, as shown in FIG. 3, the side surface 3c on the retraction side due to the eccentricity of the eccentric shaft 3a.
Then, a gap s1 is formed between the inner peripheral surfaces of the rolling bearings 5, the leaf springs 6 are pressed and deformed, and a large elastic force in the eccentric direction is applied to the rolling bearings 5.

The rolling bearing 5 is fixed to the through hole at the center of the disk-shaped friction roller 7 by press-fitting. The outer periphery of the friction roller 7 forms a friction roller surface, and is formed on the disk-shaped side surface of the friction roller 7. A plurality of through-holes 7a in the axial direction of the input shaft 3 are formed at equal angles on the same radius (pitch circle radius).

When the friction roller 7 is eccentrically rotated by the rotation of the eccentric shaft 3a of the input shaft 3 in a state where the friction roller 7 is incorporated in the friction inner roller 8, the friction roller 7 has a concave hole 3b of the eccentric shaft 3a. Leaf spring 6 pressurized and fitted inside
Functions as a pressing-out means for pressing the friction roller 7 against the friction inner roller, and the pressure becomes a force of the friction roller 7 pressing the friction inner roller 8 via the rolling bearing 5.

Due to the pressure contact force, a frictional force is generated between the friction roller 7 and the friction inner roller 8, and the frictional force and the force acting on the eccentric shaft 3a by the torque of the input shaft 3 are combined. A rotational torque is generated on the friction roller 7.

At this time, if the rotation ratio (reduction ratio) of the friction roller 7 to the rotation speed of the input shaft 3 is 1 / R, 1 / R
R = (Do−Dr) / Dr (Do: inner diameter of inner friction roller 8, Dr: inner diameter of friction roller 7, Dr = Do−2e), and diameter Dr of friction roller 7 becomes inner diameter Do of inner friction roller 8
, The smaller the eccentric distance e, the higher the rotation ratio.

The surface pressure P ₁ between the friction roller 7 and the inner friction roller 8 is P ₁ = T / μ · Dr (T: output torque,
μ: friction coefficient between the friction roller 7 and the friction inner roller 8)
The surface pressure P ₁ is given by the spring force of the leaf spring 6.

The output shaft 4 is provided with a disk 4a having an integral structure. The disk 4a has a plurality of through holes 7
a and a plurality of transmission shafts 11 that engage with each other via the driven roller 12 and transmit torque from the friction roller 7 to the output shaft 4 at equal angles on the same radius (pitch circle radius) on the disk 4a. It is fixed to.

The pitch radius and pitch (or angle) of the plurality of transmission shafts 11 are the same as the pitch radius and pitch (or angle) of the plurality of through holes 7a of the friction roller 7. .

The driven roller 12 is rotatably mounted on each transmission shaft 11 and is locked by the retaining ring 9 so as not to come off.

Since the friction roller 7 has an eccentric distance of e with respect to the output shaft 4, the diameter of the through hole 7a of the friction roller 7 is 2e larger than the diameter of the driven roller 12 mounted on the transmission shaft 11. Only so that there is no interference when combined.

With the above configuration, in the differential friction roller reduction device of the present embodiment, the rotation and the torque of the friction roller 7 decelerated at the high reduction ratio are directly used as the output rotation and the output torque at the high reduction ratio. To the output shaft 4 via the transmission shaft 11.

On the other hand, in such a differential friction roller reduction device, the rolling bearing 5 is rotated by the eccentric shaft 3a which rotates at a high speed, and at the same time, the pressure contact force of the friction roller 7 which presses the friction inner roller 8 is applied. The rolling elements (rollers or balls) of the rolling bearing 5 gradually wear.

The friction roller 7, the friction inner roller 8, the rolling bearing 5, and the eccentric shaft 3a all have high rigidity and high abrasion resistance. Therefore, the wear is small in a good lubricating environment. In the case of a structure in which the eccentric shaft 3a and the rolling bearing 5 are directly fitted to each other and the frictional force is maintained by elasticity due to slight deformation of a high-rigidity component as in a roller reduction gear, there is no danger after the operation, and When the rolling elements of the bearing 5 wear, elasticity due to slight deformation of the high-rigidity parts is lost, and the surface pressure between the friction roller 7 and the inner friction roller 8 supported by this elasticity is reduced, so that the frictional force is lost. As a result, the power transmission torque decreases.

However, in the differential friction roller reduction device of the present embodiment, an elastic body such as a leaf spring 6 is interposed between the eccentric shaft 3a and the rolling bearing 5 so that the peripheral surface of the friction roller 7 is subjected to friction. As a pressing-out means for pressing against the inner surface of the roller 8, even if the rolling element of the rolling bearing 5 wears out, a configuration in which the surface pressure between the friction roller 7 and the friction inner roller 8 can be maintained is large, so that long-term power The transmission performance can be secured.

A differential friction roller reduction device according to a second embodiment of the present invention will be described with reference to FIGS. FIG.
6 is a side sectional view of the differential friction roller reduction device of the present embodiment, FIG. 6 is a front sectional view taken along the line BB in FIG. 5, and FIG. 7 is an engagement state between an eccentric shaft and a leaf spring at the center in FIG. FIG.

In FIGS. 5 to 7 of this embodiment, the same parts as those in FIGS. 1 to 4 of the first embodiment described above are denoted by the same reference numerals, and the description thereof will be omitted. The parts are mainly explained to facilitate understanding. This is the same in other embodiments described later.

The difference between the differential friction roller reduction device of the second embodiment and the differential friction roller reduction device of the first embodiment is that the eccentric shaft 23a of the input shaft 23 is replaced by a rectangular cross section instead of an elliptical cross section axis. This is to clarify the eccentric direction as the axis.

Further, since the eccentric shaft 23a has a rectangular cross section, the rolling bearing 25 cannot be directly mounted on the eccentric shaft 23a. Therefore, the square hole cylinder 27 that is fitted externally to the eccentric shaft 23a and internally fitted to the rolling bearing 25 is used. Since the leaf spring 26 is interposed between the eccentric shaft 23a and the square hole cylinder 27, other components are the same as those of the first embodiment.

In the drawing, a casing lid 2 is attached to a casing 1, and an input shaft 23 is
And the output shaft 24 are rotatably supported concentrically. Inside the casing 1, the friction inner roller 8 is press-fitted concentrically with the input shaft 23, and the rotation direction is fixed.

The output shaft 24 is mounted on the casing lid 2 with the bearing 1.
The bearing cover 2 can be rotated in the axial direction through
2. It is fixed and supported by the bearing nut 21. The input shaft 23 is supported by the casing 1 via the bearing 13, and is supported via a bearing 16 in a center hole of the output shaft 24.
The bearing 13 is axially fixed to the casing 31 by the bearing cover 14.

The input shaft 23 is formed with an eccentric shaft 23a which is parallel to the rotation center axis and eccentric by a distance e. The eccentric shaft 23a has a rectangular cross section having a parallel plane along the eccentric direction, and the axial width in the eccentric direction is slightly smaller than the axial width perpendicular to the eccentric direction.

A square cylinder 27 is fitted around the input shaft 23. The square cylinder 27 is slidable along a parallel plane along the eccentric direction of the eccentric shaft 23a. Clearance s between the side of the side or the side of the retraction side
2 has a square hole.

The rectangular cylinder 27 is press-fitted inside the rolling bearing 25, and a gap between the inner surface of the rectangular cylinder 27 and the side surface 23b on the projecting side due to the eccentricity of the eccentric shaft 23a is provided with a pressurized leaf spring. 26 is sandwiched. Square hole cylinder 27 is eccentric shaft 23a
And can slide in the eccentric direction by the gap s2.

Rolling bearing 2 with square hole cylinder 27 pressed inside
5 is fixed to the through hole at the center of the disc-shaped friction roller 28 by press-fitting, and the friction roller 28 is incorporated in the friction inner roller 8. FIG.
This shows a state in which the eccentric shaft 23a and the pressurized leaf spring 26 are fitted into the square hole cylinder 27 in a free state that is not combined with the eccentric shaft 23a. It is in contact with the hole cylinder 27.

When the friction roller 28 is combined with the friction inner roller 8 in the casing 1, as shown by a two-dot chain line in FIG.
A gap s2 is formed between 3c and the square hole cylinder 27, the leaf spring 26 is pressed and deformed, and a large elastic force is applied to the rolling bearing 25 via the square hole cylinder 27.

The rolling bearing 25 is a disk-shaped friction roller 28.
Is fixed to the through hole at the center of the roller by press-fitting.
Forms a friction roller surface, and a plurality of through-holes 28a in the axial direction of the input shaft 23 are formed on the disc-shaped side surface of the friction roller 28 at equal angles on the same radius (pitch circle radius). It is open.

When the friction roller 28 is incorporated in the friction inner roller 8 and the friction roller 28 is eccentrically rotated by the rotation of the eccentric shaft 23a of the input shaft 23, the overhanging surface 23b and the square hole due to the eccentricity of the eccentric shaft 23a are formed. A leaf spring 26 pressurized and fitted into the gap of the cylinder 27 functions as a pressing means for pressing the friction roller 28 against the friction inner roller, and the pressure is applied to the friction roller 28 via the rolling bearing 25 by the friction roller 28. It becomes the force to press.

Due to the pressing force, a frictional force is generated between the friction roller 28 and the friction inner roller 8, and the frictional force and the input shaft 2
The torque acting on the shaft center of the eccentric shaft 23a due to the torque of No. 3 is combined to generate a rotational torque on the friction roller 28.

The rotation ratio (reduction ratio) of the friction roller 28 to the rotation speed of the input shaft 23 according to the present embodiment,
The formula for calculating the surface pressure between the roller and the friction inner roller 8 is the same as that in the first embodiment, and the surface pressure is given by the spring force of the leaf spring 26.

The output shaft 24 is provided with a disk 24a in an integral structure. The disk 24a is engaged with each of the plurality of through holes 28a of the friction roller 28 via the driven roller 12, and the friction roller 28 A plurality of transmission shafts 11 for transmitting more torque to the output shaft 24 are fixedly mounted on the disk 24a at equal angles on the same radius (pitch circle radius).

The pitch radius and pitch (or angle) of the plurality of transmission shafts 11 are the same as the pitch radius and pitch (or angle) of the plurality of through holes 28 a of the friction roller 28. .

The driven roller 12 is rotatably mounted on each transmission shaft 11 and is locked by the retaining ring 9 so as not to come off.

Since the friction roller 28 has an eccentric distance e with respect to the output shaft 24, the through hole 2 of the friction roller 28
8a is the diameter of the driven roller 1 mounted on the transmission shaft 11.
It is made larger by 2e than the diameter of 2 so that there is no interference at the time of combination.

With the above-described configuration, in the differential friction roller reduction device of the present embodiment, the rotation and torque of the friction roller 28 decelerated at the high reduction ratio are directly used as the output rotation and output torque of the high reduction ratio. To the output shaft 24 via the transmission shaft 11.

In the present embodiment, the eccentric shaft 23a and the square tube cylinder 27 are provided in the same manner as described in the first embodiment.
An elastic body such as a leaf spring 26 is interposed in a gap between the friction roller 28 and the inner surface of the inner friction roller 8 as a pressing-out means. Because the range in which the surface pressure between the roller 28 and the friction inner roller 8 can be maintained is large, long-term power transmission performance can be ensured.

A differential friction roller reduction device according to a third embodiment of the present invention will be described with reference to FIG. FIG. 8 is a side sectional view of the differential friction roller reduction device of the present embodiment.

The differential friction roller reduction device of this embodiment has three sets of elliptical cross-sections similar to the eccentric shaft 3a formed on the input shaft 3 of the differential friction roller reduction device of the first embodiment. The eccentric shafts 33b, 33a, and 33c are shifted by 180 degrees in the axial direction of the input shaft 33 in the axial direction of the input shaft 33 with the same eccentric dimension e, and their axial lengths are set to 1: 2: 1.
And provided continuously.

Further, the respective eccentric shafts 33b, 33a, 3
3c, rolling bearings 35, 5, 35, friction rollers 37, 7, 37 having the same outer diameter, each friction roller 37,
The pressurized leaf springs 36, 6 and 36, which are pressing means for pressing the inner rollers 7 and 37 against the inner friction roller 38, also have a width (that is, a length in the input axis direction) and a pressing force of 1: 2.
Three sets are provided side by side at a ratio of 1: 1, and friction rollers 37,
7 and 37 are inscribed in a common wide friction inner roller 38, and take out a reduced rotation from the output shaft 4 via a common transmission shaft 41.

In the drawing, a casing lid 32 is attached to a casing 31, and in a combined state thereof, the input shaft 33 and the output shaft 4 are rotatably supported concentrically. Inside the casing 31, a friction inner roller 38 is fixedly press-fitted concentrically with the input shaft 33, and is fastened by the casing lid 32, and its rotation direction is fixed to the casing 31.

The output shaft 4 is rotatably supported by the casing lid 32 via the bearings 18, 18, and is fixed in the axial direction by the bearing cover 22 and the bearing nut 21.

The input shaft 33 is supported by the casing 31 via the bearing 13, and is supported by the center hole of the output shaft 4 via the bearing 16. The bearing 13 is axially fixed to the casing 31 by a bearing cover 14.

The input shaft 33 has eccentric shafts 33b, 33a and 33c which are parallel to the center axis of rotation and eccentric by the same distance e.
Are sequentially formed in the axial direction of the input shaft. Eccentric shaft 33
The axial length of b and the eccentric shaft 33c is half the axial length of the eccentric shaft 33a. The eccentric shaft 33b and the eccentric shaft 3
The eccentric phase angle 3c is an angular position rotated by 180 degrees with respect to the eccentric shaft 33a.

Each of the eccentric shafts 33b, 33a, 33c has a fixed gap s1 with the inner surface of the rolling bearings 35, 5, and 35, which are respectively fitted on the protruding side or the retracted side due to the eccentricity.
The shaft width in the eccentric direction is formed in an elliptical cross section slightly smaller than the shaft width perpendicular to the eccentric direction.

Each of the eccentric shafts 33b, 33a, and 33c is provided with a quadrangular concave hole on the overhanging outer surface.
The concave holes of 3b and 33c are half the width of the concave hole of the eccentric shaft 33a (that is, the axial length).

A leaf spring 6 made of a plurality of bent steel plates is fitted in the concave hole of the eccentric shaft 33a, and a leaf spring 36 having a half width of the leaf spring 6 is fitted in the concave holes of the eccentric shafts 33b and 33c. Have been.

The rolling bearing 5 is externally fitted on the outer periphery of the eccentric shaft 33a, and the rolling bearings 35 are externally fitted on the outer periphery of the eccentric shafts 33b and 33c, respectively, but the rolling bearing 5 and the rolling bearings 35, 35 are provided. Can move in the eccentric direction by a gap s1 with respect to the eccentric shaft on which each is fitted.

FIG. 4 shows a state in which the eccentric shaft 3a and the pressurized leaf spring 6 are fitted into the rolling bearing 5 when the friction roller 7 is not combined with the inner friction roller 8 in the first embodiment. As shown in FIG. 4, the eccentric shaft 33a and the pressurized leaf spring 6 are applied to the rolling bearing 5 when the friction roller 7 is not combined with the inner friction roller 38 in the present embodiment. The fitted state may also be indicated.

Further, the eccentric shafts 33b, 33c and the pressurized leaf springs 36, 36 are fitted into the rolling bearings 35, 35 when the friction rollers 37, 37 are not combined with the friction inner roller 38, respectively. The state can be similarly shown.

However, the friction roller 7
Is combined with the friction inner roller 38, a gap s1 is formed between the side surface on the retraction side due to the eccentricity of the eccentric shaft 33a and the inner peripheral surface of the rolling bearing 5, and the leaf spring 6 is pressed and deformed. A large elastic force is applied to the rolling bearing 5.

When the friction rollers 37, 37 are combined with the friction inner roller 38, the eccentric shafts 33b, 33
c and the rolling bearings 35, 3
5, a gap s1 is formed between the leaf springs 36 and 36.
Is pressed and deformed, and a large elastic force is applied to each rolling bearing 35,
35. These states are the same as the states shown in FIGS. 2 and 3 for the first embodiment.

The rolling cylinders 34, 17 and the partition plates 47, 47 are arranged such that the rolling bearings 35, 5, 35 have eccentric shafts 33b, 33a, 33c.
It is installed so that it does not shift in the axial direction above.

A disk-shaped friction roller 7 is fixed to the outer periphery of the rolling bearing 5 by press-fitting in a through hole at the center thereof, and disk-shaped friction rollers 37, 37 are mounted on the outer periphery of the rolling bearings 35, 35. Is fixed by press-fitting in a through hole at the center thereof, and the outer circumference of the friction rollers 37, 7, and 37 forms a friction roller surface, and each of the friction rollers has an equal angle (pitch circle radius) on the side surface. A plurality of the shafts 37a, 7a, 37a in the axial direction of the input shaft 33 are opened at the positions.

Each friction roller 3 is placed inside the friction inner roller 38.
The eccentric shaft 33 of the input shaft 33 is incorporated with 7, 7, 37
When eccentric rotation is caused by the rotation of b, 33a, 33c,
In the friction roller 7, the pressure of the leaf spring 6 pressurized and fitted into the concave hole of the eccentric shaft 33 a becomes a force for the friction roller 7 to press the friction inner roller 38 via the rolling bearing 5, and The pressure of the leaf springs 36, 36 pressurized and fitted in the concave holes of the eccentric shafts 33b, 33c is applied to the friction rollers 37, 3 via the rolling bearings 35, 35.
7 is a force for pressing the inner friction roller 38.

Because of this pressing force, each friction roller 37,
7, 37 and the friction inner roller 38, a friction force is generated, and the eccentric shafts 33b,
The forces acting on the axes of the shafts 3a and 33c are combined to generate rotational torque on each of the friction rollers 37, 7, and 37.

At this time, the formulas for calculating the rotation ratio (reduction ratio) of the friction rollers 37, 7, 37 to the rotation speed of the input shaft 33, and the surface pressure between the friction rollers 37, 7, 37 and the friction inner roller 38 are as follows. This surface pressure is given by the spring force of the leaf springs 36, 6, 36.

A plurality of through holes 37 a, 7 a of the friction rollers 37, 7, 37 are formed in a disk 4 a integral with the output shaft 4.
A plurality of transmission shafts 41 are provided which engage with the driving rollers 12a, 37a via the driven rollers 12a, 12, 12a and transmit torque from the friction rollers 37, 7, 37.

The transmission shaft 41 has a pitch circle radius and a pitch (or angle) corresponding to the pitch circle radius and the pitch (or angle) of the plurality of through holes 37a, 7a, 37a of the friction rollers 37, 7, 37, respectively. ) Is fixed so as to be the same as).

The driven rollers 12a, 12 and 12a have the same outer diameter, are rotatably mounted on the respective transmission shafts 41, are locked by the retaining ring 9 so as not to come off, and respectively have through holes 37a, 7a and 37a. Located within.

Since the friction rollers 37, 7, 37 have an eccentric distance of e with respect to the output shaft 4, the friction rollers 37, 7,
The diameter of each through hole 37a, 7a, 37a of 7, 37 is larger than the diameter of the driven rollers 12a, 12, 12a of the transmission shaft 41 by 2e so that there is no interference at the time of combination.

The friction roller 3 thus decelerated
The rotations and torques of 7, 7, and 37 are transmitted to the output shaft 4 via a plurality of transmission shafts 41 as output rotations and output torques as they are.

The seat rings 42, 4 provided on each transmission shaft 41
Reference numerals 2 and 42 are provided to prevent the positions of the friction rollers 37, 7, and 37 from shifting.

In the case of the present embodiment, the friction rollers 37,
Since the frictional force transmission width (length in the input shaft direction) of 7, 37 is twice as large as that of the first embodiment, the power transmission capacity is doubled.

The pressing force against the friction inner roller 38 is such that the friction rollers 37
The eccentric shafts 33b, 33a, 3
3c, the bending moment of the input shaft 33 loaded in the input shaft 33 can be balanced in the input shaft 33.
While significantly reducing the load on bearings 13 and 16
Friction rollers 37, 7, 37 and bearings 35, 5, 35
Eccentric rotating weight can be balanced.

A differential friction roller reduction device according to a fourth embodiment of the present invention will be described with reference to FIG. FIG. 9 is a side sectional view of the differential friction roller reduction device of the present embodiment.

The differential friction roller reduction device of the present embodiment is similar to the eccentric shaft 23a formed on the input shaft 23 of the above-described differential friction roller reduction device of the second embodiment shown in FIGS. Three sets of eccentric shafts 43b, 43 having a rectangular cross section
The phases a and 43c are sequentially changed by 180 degrees in the axial direction of the input shaft 43 with the same eccentric dimension e, and their lengths in the input shaft direction are connected at a ratio of 1: 2: 1.

Further, the respective eccentric shafts 43b, 43a, 4
3c, square bearings 44, 27, 44, rolling bearings 45, 25, 45, friction rollers 48, 2 having the same outer diameter.
8, 48, the pressurized leaf springs 46, 26, 46 which are pressing means for pressing the friction rollers 48, 28, 48 against the friction inner roller 38 also have their widths (namely, lengths in the input shaft direction). Three sets of pressing force are provided side by side at a ratio of 1: 2: 1, and the friction rollers 48, 28, 48 are inscribed in a common wide friction inner roller 38 and output through a common transmission shaft 41. The configuration is such that decelerated rotation is taken out from the shaft 24.

In the drawing, a casing lid 32 is attached to a casing 31, and in a combined state thereof, the input shaft 43 and the output shaft 24 are supported concentrically and freely to rotate. Inside the casing 31, a friction inner roller 38 is fixedly press-fitted concentrically with the input shaft 43, and is tightened by the casing lid 32, and its rotation direction is fixed to the casing 31.

The output shaft 24 is rotatably supported by the casing lid 32 via the bearings 18, 18, and is fixed in the axial direction by the bearing cover 22 and the bearing nut 21.

The input shaft 43 is supported by the casing 31 via the bearing 13, and is supported via the bearing 16 in the center hole of the output shaft 24. The bearing 13 is a casing 31
Is axially fixed by the bearing cover 14.

The input shaft 43 has eccentric shafts 43b, 43a, 43c parallel to the rotation center axis and eccentric by the same distance e.
Are sequentially formed in the axial direction of the input shaft 43. The axial length of the eccentric shaft 43b and the eccentric shaft 43c is set to half of the axial length of the eccentric shaft 43a. The eccentric phase angle between the eccentric shaft 43b and the eccentric shaft 43c is 180 degrees with respect to the eccentric shaft 43a.
The angle is turned by degrees.

Each of the eccentric shafts 43b, 43a and 43c forms a rectangular cross section having a parallel plane along the eccentric direction.
A square hole cylinder 27 is fitted on 3a. The rectangular cylinder 27 is slidable along a plane parallel to the eccentric direction of the eccentric shaft 43a, and a rectangular hole such that a gap s2 is formed between the eccentric shaft 43a and the flared side or the retracted side due to the eccentricity. have.

The square hole cylinder 27 is press-fitted inside the rolling bearing 25, and a pressurized leaf spring 26 is sandwiched in a gap between the inner surface of the square hole cylinder 27 and the side surface of the eccentric shaft 43a on the projecting side due to the eccentricity. ing. The square hole cylinder 27 is guided by the eccentric shaft 43a and can slide in the eccentric direction by the gap s2.

When the friction roller 28 is not combined with the friction inner roller 38 and the square hole cylinder 27 is free, the eccentric shaft 4
The eccentric shaft 23a in FIG. 7 may be replaced with an eccentric shaft 43a in the front view in a state where the plate spring 3a and the pressurized leaf spring 26 are fitted.

The eccentric shaft 43b and the eccentric shaft 43c are
3a, each part around the eccentric shaft 43b and the eccentric shaft 43c, square hole cylinders 44, 44, rolling bearings 45, 45,
The front shapes of the leaf springs 46, 46 and the friction rollers 48, 48 have the same shape as the shape around the eccentric shaft 43a shown in FIG.

Eccentric shaft 43b and eccentric shaft 43c viewed from the side
Surrounding parts, square hole cylinders 44, 44, rolling bearings 45, 4
5, the widths of the leaf springs 46, 46 and the friction rollers 48, 48 (that is, the lengths in the input axis direction) are all around the eccentric shaft 43a, the square cylinder 27, the rolling bearing 25, the leaf spring 26, and the friction roller 28. (Width in the input axis direction). The square hole cylinders 44, 44 are guided by the eccentric shafts 43b, 43c and can slide in the eccentric direction by the gap s2.

The rolling bearings 45, 25, and 45 have eccentric shafts 43b, 43a, and 43, respectively.
It is installed in order not to shift in the axial direction on c.

A disk-shaped friction roller 28 is fixed to the outer periphery of the rolling bearing 25 by press fitting, and disk-shaped friction rollers 48 are fixed to the outer periphery of the rolling bearings 45 by press fitting, respectively. The outer circumference of the friction rollers 48, 28, 48 forms a friction roller surface, and the input shaft 43 is located on the side surface of each of the friction rollers at an equal angle on the same radius (pitch circle radius).
A plurality of through holes 48a, 28a, 48a in the axial direction are provided.

Each of the friction rollers 48 in the friction inner roller 38
When the eccentric shafts 43b, 43a, and 43c of the input shaft 43 are eccentrically rotated by incorporating the eccentric shafts 43b, 43a, respectively, the pressure of the leaf spring 26 pressurized and fitted to the eccentric shaft 43a is applied to the friction roller 28. The friction roller 28 becomes a force for pressing the friction inner roller 38 via the rolling bearing 25, and the eccentric shafts 43b,
The pressure of the leaf springs 46, 46 pressurized and fitted into 3 c is applied to the friction rollers 48, 48 via the rolling bearings 45, 45.
Is the force for pressing the inner friction roller 38.

Due to this pressing force, each of the friction rollers 48, 2
8 and 48 and the friction inner roller 38, a frictional force is generated, and the eccentric shafts 43b and 43
The forces acting on the shaft centers a and 43c are combined to generate a rotational torque on each of the friction rollers 48, 28 and 48.

At this time, the formulas for calculating the rotation ratio (reduction ratio) of the friction rollers 48, 28, 48 to the rotation speed of the input shaft 43 and the surface pressure between the friction rollers 48, 28, 48 and the friction inner roller 38 are as follows. The surface pressure is given by the spring force of the leaf springs 46, 26, 46.

A plurality of through holes 48 of the friction rollers 48, 28, 48 are formed in a disk 24 a integral with the output shaft 24.
a, 28a, 48a and driven rollers 12a, 12, 12, 12
A plurality of transmission shafts 41 are provided which engage with each other via a to transmit torque from the friction rollers 28, 48, 48.

The transmission shaft 41 has a pitch circle radius and a pitch (or angle) corresponding to the pitch circle radius and the pitch (or angle) of the plurality of through holes 48a, 28a, 48a of the friction rollers 48, 28, 48, respectively. ) Is fixed so as to be the same as).

The driven rollers 12a, 12, 12a have the same outer diameter, are rotatably mounted on the respective transmission shafts 41, are locked by the retaining ring 9 so as not to come out, and are respectively provided with through holes 48a, 28a, 48a. Located within.

The friction rollers 48, 28, 48 are connected to the output shaft 24.
Has an eccentric distance of e with respect to
The diameter of each through hole 48a, 28a, 48a of 8, 28, 48 is determined by the driven rollers 12a, 12, 12a of the transmission shaft 41.
Is made larger by 2e than the diameter to prevent interference at the time of combination.

The friction roller 2 thus decelerated
The rotations and torques of 8, 48, 48 are transmitted to the output shaft 24 via a plurality of transmission shafts 41 as output rotation and output torque as they are.

Seat rings 42, 4 provided on each transmission shaft 41
Reference numerals 2 and 42 are provided to prevent the positions of the friction rollers 48, 28 and 48 from shifting.

In the case of the present embodiment, the friction rollers 48, 2
Since the frictional force transmission width (length in the input shaft direction) of 8, 8 is twice as large as that of the first and second embodiments, the power transmission capacity is doubled.

The pressing force against the friction inner roller 38 is applied to the friction roller 28 by the friction rollers 48, 180.
, The eccentric shafts 43b, 43a,
43c, the bending moment of the input shaft 43 loaded in the input shaft 43 can be balanced.
The load on the bearings 13, 16 is significantly reduced, while the friction rollers 48, 28, 48 and the rolling bearings 4
Eccentric rotational weights such as 5, 25, and 45 can be balanced.

[0117]

(1) According to the first aspect of the present invention, the differential friction roller reduction device is rotatably supported by the casing via the bearing, and the shaft width in the eccentric direction parallel to the rotation center axis is eccentric. An input shaft provided with an eccentric shaft smaller than a shaft width at right angles to the input shaft, and a plurality of through holes in the input shaft direction are formed at equal angular positions on the same pitch circle on the side surface with a friction roller surface formed on the outer periphery. A disk-shaped friction roller having a through hole in the
A rolling bearing provided between the eccentric shaft and a press-fitted through hole of the friction roller; and a friction inner roller fixed in the casing at a position concentric with the input shaft and surrounding the friction roller. Press-out means provided between the eccentric shaft and the rolling bearing to press out the friction roller in the eccentric direction via the rolling bearing and press against the friction inner roller;
A disk in which a plurality of transmission shafts that engage with each of the plurality of through holes and transmit torque from the friction roller are fixed at equiangular positions on a pitch circle having the same radius as the through hole; And an output shaft rotatably supported concentrically with the input shaft via a bearing in a casing through a bearing, so that the rotation of the input shaft causes the eccentric shaft of the input shaft via a rolling bearing. When the friction roller externally fitted via the rolling bearing rotates eccentrically, the friction roller surface is securely pressed against the inner surface of the friction inner roller fixed in the casing by the action of the pressing-out means and rolls. High speed reduction ratio differential reduction of the friction roller caused by the friction force between the friction roller and the friction inner roller and the force acting on the axis of the eccentric shaft due to the torque of the input shaft, quietly without generating noise Rotation and torque via transmission shaft To the output shaft, and even if the rolling elements of the rolling bearing wear, the pressing force can maintain the surface pressure between the friction roller and the friction inner roller, ensuring long-term power transmission performance. Can be.

(2) According to the invention of claim 2, claim 1
In the differential friction roller reduction gear transmission described in the above, the eccentric shaft has an elliptical cross-section, the clearance between the side surface on the overhang side or the side on the retraction side due to eccentricity and the inner surface of the same rolling bearing when the rolling bearing is externally fitted. And the same rolling bearing can be moved in the eccentric direction, and has a quadrangular concave hole on the side surface of the same protruding side, and the pressing means is provided between the inner surface of the rolling bearing and the rectangular concave hole. The frictional roller is eccentrically rotated by the rotation of the input shaft, so that the inner surface of the rolling bearing and the side surface of the eccentric shaft are provided. The pressure of the leaf spring pressurized in the gap with the square concave hole becomes a force for the friction roller to press the friction inner roller, and even if the rolling bearing or the like is worn, the friction force between the rollers works reliably, Differential speed reduction at high reduction ratio Large range that can be held and the high transmission torque, it is possible to ensure a more long-term power transmission performance.

(3) According to the invention of claim 3, claim 1
In the differential friction roller reduction gear device described in the above, the eccentric shaft has a rectangular cross section having a parallel plane along the eccentric direction, is slidable with the parallel plane, and is a side surface or a retracting side on the overhang side due to the eccentricity of the eccentric shaft. A square hole tube having a square hole forming a gap between the side surface of the rolling bearing, the square hole tube is press-fitted inside the rolling bearing, and the pressing-out means is the square hole tube. Since the plate spring is configured to be pressurized and fitted into the gap between the inner surface and the side surface of the eccentric shaft on the side where the eccentric shaft extends, in addition to the effect of the invention of claim 1, the eccentric shaft is changed to a rectangular shaft having a rectangular cross section. Formed, and the rolling bearing is externally fitted via the square hole cylinder, so that the eccentric direction of the friction roller is ensured, and when the friction roller rotates eccentrically by the rotation of the input shaft, the inner surface of the square hole cylinder and the side surface of the eccentric shaft The pressure of the pressurized leaf spring in the gap between The roller acts as a force to press the friction inner roller, and even if the rolling bearings wear, the frictional force between the rollers works reliably, and the range in which the differential reduction rotation at a high reduction ratio and the high transmission torque can be held is large. Long-term power transmission performance can be ensured.

(4) According to the invention of claim 4, claim 1
Alternatively, in the differential friction roller reduction device according to claim 2, the eccentric shaft of the input shaft changes the eccentric phase angle by 180 degrees in the axial direction of the input shaft with the same eccentric dimension in order to make the axial length one pair. Three sets of eccentric shafts provided in series at a ratio of two to one, wherein the friction roller, the rolling bearing, and the pressing means are combined with each of the three sets of eccentric shafts, and the pressing force transmitting the width thereof is transmitted. Three sets of side-contacting friction rollers having the same outer diameter, three sets of side-contacting rolling bearings, and three sets of side-contacting pressing-out means, wherein the set-out force is in the order of 1: 2: 1, Is a wide friction inner roller commonly circumscribing the three sets of friction rollers having the same outer diameter that are in contact with the side, and the output shaft is differentially driven from the three sets of friction rollers that are in contact with each other through the common transmission shaft. It is configured to take out deceleration rotation As a result, in addition to the effects of the first or second aspect of the present invention, the power transmission capacity is doubled, and the pressing force against the friction roller acts in opposition, so that the bending moment of the input shaft is reduced within the input shaft. The balance reduces the load on the bearing of the input shaft significantly, and at the same time balances the eccentric rotational weight, improves the rotational performance, and makes it possible to provide a reduction gear with less vibration and noise.

(5) According to the invention of claim 5, claim 3
In the differential friction roller reduction device described in the above, the eccentric shaft of the input shaft has the same eccentric dimension and is sequentially 1 in the axial direction of the input shaft.
The eccentric phase angle is changed by 80 degrees, and three sets of eccentric shafts are provided so that the axial lengths thereof are connected in a ratio of 1: 2: 1.
Three sets of friction rollers having the same outer diameter, three sets of rolling bearings, which are in contact with each other and have a ratio of 1 to 2 to 1 in which the width and the pressing force to be transmitted are combined with each of the sets of eccentric shafts, Three sets of side-contacting pressing means, wherein the inner friction roller is a wide inner friction roller commonly circumscribing the three sets of the same outer diameter friction rollers, and the output shaft is in side contact with the three inner rollers. Since the differential deceleration rotation is taken out from the three sets of friction rollers via the common transmission shaft, the power transmission capacity is doubled in addition to the effect of the invention of claim 3, and Since the pressure contact force against the friction roller works oppositely, the bending moment of the input shaft is balanced in the input shaft and the load on the bearing of the input shaft is remarkably reduced, and at the same time, the eccentric rotation weight is balanced and the rotation performance is improved. Less vibration and noise It becomes possible to device.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a differential friction roller reduction device according to a first embodiment of the present invention.

FIG. 2 is a front sectional view taken along the line AA in FIG.

FIG. 3 is a detailed view of a central portion of FIG. 2;

FIG. 4 is an explanatory view of an engagement state between an eccentric shaft and a leaf spring in FIG. 3;

FIG. 5 is a side sectional view of a differential friction roller reduction device according to a second embodiment of the present invention.

FIG. 6 is a front sectional view taken along line BB in FIG. 5;

FIG. 7 is an explanatory diagram of an engaged state between an eccentric shaft and a leaf spring at a central portion in FIG. 6;

FIG. 8 is a side sectional view of a differential friction roller reduction device according to a third embodiment of the present invention.

FIG. 9 is a side sectional view of a differential friction roller reduction device according to a fourth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Casing 2 Casing lid 3 Input shaft 3a Eccentric shaft 4 Output shaft 5 Rolling bearing 6 Leaf spring 7 Friction roller 7a Through hole 8 Friction inner roller 11 Transmission shaft 12, 12a Driven roller 23 Input shaft 23a Eccentric shaft 24 Output shaft 25 Rolling Bearing 26 Leaf spring 27 Square hole cylinder 28 Friction roller 28a Through hole 31 Casing 32 Casing lid 33 Input shaft 33a, 33b, 33c Eccentric shaft 35 Rolling bearing 36 Leaf spring 37 Friction roller 38 Internal friction roller 38a Through hole 41 Transmission shaft 43 Input Shafts 43a, 43b, 43c Eccentric shaft 45 Rolling bearing 46 Leaf spring 48 Friction roller 48a Through hole

Claims (5)

[Claims] An input shaft, which is rotatably supported by a casing via a bearing, and has an eccentric shaft parallel to the rotation center axis and having an eccentric shaft width smaller than an eccentric shaft width at right angles to the eccentric direction, and friction on the outer periphery. A disc-shaped friction roller having a roller surface formed therein and having a plurality of through-holes in the input axis direction formed at equal angles on the same pitch circle on the side surface and having a through-hole in the center; and a through-hole of the friction roller A rolling bearing provided between the shaft and the eccentric shaft; a friction inner roller fixed in the casing at a position concentric with the input shaft and surrounding the friction roller; Pressing means for pressing the friction roller in an eccentric direction and pressing against the friction inner roller provided between the friction roller and the friction roller through the same rolling bearing provided between the friction roller and the rolling roller; Multiple transmissions transmitting torque A disk having a shaft fixed at an equiangular position on a pitch circle having the same radius as the through hole, and an output which is rotatably supported concentrically with the input shaft via a bearing in a casing in an integral structure with the disk. A differential friction roller reduction device comprising: a shaft; 2. The differential friction roller reduction device according to claim 1, wherein the eccentric shaft has an elliptical cross-section, and the eccentric shaft has an overhanging side surface or a retracting side surface when the rolling bearing is externally fitted. A gap is formed between the rolling bearing and the inner surface of the rolling bearing so that the rolling bearing can be moved in the eccentric direction, and a side surface on the side of the protruding side has a rectangular recessed hole. A differential friction roller reduction device, comprising a leaf spring pressurized and fitted between the rectangular concave hole. 3. The differential friction roller reduction device according to claim 1, wherein the eccentric shaft has a rectangular cross section having a parallel plane along an eccentric direction, and is slidable with the parallel plane. A square hole cylinder having a square hole that forms a gap between the side surface on the overhanging side or the side surface on the retraction side due to eccentricity is externally fitted, and the square hole cylinder is press-fitted inside the rolling bearing, The differential friction roller reduction device according to claim 1, wherein the pressing means is a leaf spring pressurized and fitted in a gap between the inner surface of the square hole cylinder and a side surface of the eccentric shaft on the side of the protruding side. 4. The differential friction roller reduction device according to claim 1, wherein the eccentric shaft of the input shaft has an eccentric phase angle of 180 degrees in the axial direction of the input shaft with the same eccentric dimension. In other words, there are three sets of eccentric shafts provided so that the axial lengths are connected in a ratio of 1: 2: 1, and the friction roller, the rolling bearing and the pressing-out means are provided on each of the three sets of eccentric shafts. Three sets of friction rollers having the same outer diameter, three sets of rolling bearings in contact with one another, and three sets of compression in contact with one another, in which the width and the pressing force to be transmitted with the width thereof are in the order of 1: 2: 1 in the above order. Means, wherein the inner friction roller is a wide inner friction roller commonly circumscribing the three sets of friction rollers having the same outer diameter, and the output shaft is shared by the three sets of adjacent friction rollers. Differential deceleration rotation via the transmission shaft A differential friction roller reduction device characterized in that the differential friction roller reduction device is configured to be driven out. 5. The differential friction roller reduction device according to claim 3, wherein the eccentric shaft of the input shaft has the same eccentric dimension and changes the eccentric phase angle by 180 degrees in the axial direction of the input shaft in order. Three sets of eccentric shafts provided in series at a ratio of 1: 2: 1, wherein the friction roller, the rolling bearing, the square hole cylinder, and the press-out means are mounted on each of the three sets of eccentric shafts. The three sets of friction rollers having the same outer diameter, the three sets of rolling bearings, and the three sets of square bore cylinders, which are in contact with each other, are set in such a manner that the width and the pressing force to be transmitted are in a ratio of 1: 2: 1 in this order. And three sets of side-contacting pressing means, wherein the inner friction roller is a wide inner friction roller commonly circumscribing the three sets of side-contact friction rollers having the same outer diameter, and the output shaft is connected to the same side. Differential from three sets of contacting friction rollers via the common transmission shaft A differential friction roller reduction device configured to take out reduced speed rotation.