JP7253089B2 - flexural mesh gearbox - Google Patents

Description

The present invention relates to a flexural mesh gear system.

A flexure mesh type gear device is known as a gear device that is compact and lightweight and can provide a high reduction ratio. Conventionally, a vibrating body shaft having a vibrating body, an external gear flexibly deformed by the vibrating body, a first internal gear meshing with the external gear, and an axially aligned gear with the first internal gear A second internal gear that is arranged and meshes with the external gear, a first internal gear that rotates integrally with the first internal gear, and a second internal gear that rotates integrally with the second internal gear. , a so-called flat-type flexible mesh gear device has been proposed (for example, Patent Document 1).

JP 2011-112214 A

The power consumption of the driving device for driving the flexural mesh gear system is affected not only by the friction loss of the flexural mesh gear system, but also by the moment of inertia of the flexural mesh gear system.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and an object of the present invention is to provide a flexural mesh gear system capable of reducing the moment of inertia.

In order to solve the above problems, a flexure mesh gear device according to one aspect of the present invention includes a vibrating body shaft having a vibrating body, an external gear that is flexurally deformed by the vibrating body, and an external gear. A first internal gear that meshes with the first internal gear, a second internal gear that is arranged axially in line with the first internal gear and meshes with the external gear, and a first internal gear that rotates integrally with the first internal gear. and a second internal tooth member that rotates integrally with the second internal gear, wherein the vibrating body shaft is a shaft part that rotates integrally with the vibrating body have. The flexural mesh gearbox further includes a first input bearing disposed between the shaft and the first internal tooth member, and a second input bearing disposed between the shaft and the second internal tooth member. And prepare. The outer diameters of the first input bearing and the second input bearing are smaller than the outer diameter of the vibration generator.

Arbitrary combinations of the above constituent elements, and mutual substitution of the constituent elements and expressions of the present invention in methods, devices, systems, etc. are also effective as aspects of the present invention.

According to the present invention, it is possible to provide a flexural mesh gear system capable of reducing the moment of inertia.

1 is a cross-sectional view showing a flexural mesh gear device according to a first embodiment; FIG. It is a cross-sectional view showing a flexural mesh gear device according to a second embodiment.

Hereinafter, the same or equivalent constituent elements, members, and steps shown in each drawing are denoted by the same reference numerals, and redundant description will be omitted as appropriate. In addition, the dimensions of the members in each drawing are appropriately enlarged or reduced for easy understanding. Also, in each drawing, some of the members that are not important for explaining the embodiments are omitted.

(First embodiment)
FIG. 1 is a cross-sectional view showing a flexural mesh gear device 100 according to the first embodiment. The bending mesh type gear device 100 decelerates and outputs the input rotation. The flexural mesh gear device 100 is a so-called flat type flexural mesh gear device, and includes a wave generator 2 , an external gear 4 that is flexurally deformed by the wave generator 2 , and a second gear that meshes with the external gear 4 . 1 internal gear 6, a first internal gear member 7 that rotates integrally with the first internal gear 6, and an axial direction (that is, a direction parallel to the rotation axis R) with the first internal gear 6 ( adjacent to each other) and mesh with the external gear 4, a second internal gear 9 rotating integrally with the second internal gear 8, a first internal gear 7 and a second a main bearing 16 arranged between the internal toothed member 9 . Lubricant (for example, grease) is enclosed in the meshing gear device 100, and meshing portions between the external gear 4 and the first internal gear 6 and the second internal gear 8 (hereinafter simply referred to as "meshing It lubricates each bearing, etc.

The wave generator 2 includes a vibration generator shaft 22, a first vibration generator bearing 21a arranged between the vibration generator shaft 22 and a first external tooth portion 4a (described later) of the external gear 4, and a vibration generator. and a second vibration generator bearing 21b arranged between the vibration body shaft 22 and a second external tooth portion 4b (described later) of the external gear 4 .

The vibration generator shaft 22 has a shaft portion 221 , a vibration generator 222 that rotates integrally with the shaft portion 221 , and a connection portion 223 that connects the shaft portion 221 and the vibration generator 222 .

The shaft portion 221 is an input shaft, is connected to a drive device (not shown) such as a motor, and rotates around the rotation axis R. As shown in FIG. One side (the right side in FIG. 1) of the shaft portion 221 penetrates the first internal tooth member 7 and protrudes to the outside. Hereinafter, the end portion of the shaft portion 221 that protrudes outward from the first internal tooth member 7 (the right end portion in FIG. 1) is referred to as a protruding side end portion 221a, and the shaft portion on the side opposite to the protruding side end portion 221a. The end of 221 (the left end in FIG. 1) is called the anti-protrusion side end 221b. The driving device is arranged on one side in the axial direction of the projecting side end portion 221a.

The shaft portion 221 has a hollow portion 221c. The hollow portion 221c is open at the end portion 221b opposite to the projecting side, and communicates with the meshing portion, each bearing, etc. through this opening. Therefore, the hollow portion 221c can function as a lubricant reservoir for storing lubricant to be supplied to the meshing portion, each bearing, and the like. A projecting end 221a of the hollow portion 221c is closed so that the lubricant does not leak to the outside. The hollow portion 221c may be closed with the seal cap 48 while the protruding side end portion 221a is open as shown in the drawing, or the protruding side end portion 221a is not open, that is, it is a bottomed hollow portion. good too.

The shaft portion 221 has a radial lubrication passage 221d penetrating the shaft portion 221 in the radial direction. The radial lubrication passage 221d opens into a gap between the shaft portion 221 and the first extension portion 58 where the first input bearing 30 is arranged. Therefore, the hollow portion 221c and the gap between the first extending portion 58 and the shaft portion 221 are bypassed by the radial lubrication passage 221d. The number of radial lubrication passages 221d is not particularly limited, and for example, a plurality of radial lubrication passages 221d may be provided at regular intervals in the circumferential direction.

The vibration generator 222 includes a first vibration generator 222a and a second vibration generator 222b. The first vibration generator 222a and the second vibration generator 222b respectively surround the first extension part 58 and the second extension part 68 (both described later), and the outer peripheral shape of the cross section perpendicular to the rotation axis R is Almost elliptical. The term "ellipse" as used herein is not limited to geometrically strict ellipses, and includes substantially ellipses.

The connecting portion 223 has a substantially disk shape and connects the shaft portion 221 to the first vibrating body 222a and the second vibrating body 222b. The connecting portion 223 has an axial lubrication passage 223 a axially penetrating the connecting portion 223 at the same radial position as the first input bearing 30 and the second input bearing 32 . Therefore, the axial lubrication passage 223a creates a gap between the first extension portion 58 where the first input bearing 30 is arranged and the shaft portion 221, and the second extension portion 68 where the second input bearing 32 is arranged and the shaft. The gap with the portion 221 is bypassed.

Further, the connection portion 223 has a radial lubrication passage 223b that radially extends from the axial lubrication passage 223a to the outer peripheral end of the connection portion 223 . The radial lubrication passage 223b communicates the axial lubrication passage 223a with the outer peripheral surface 222c of the first vibrating body 222a and the outer peripheral surface 222d of the second vibrating body. The radial lubrication passage 223b may further extend radially inward and communicate with the hollow portion 221c.

The number of axial lubrication passages 223a and radial lubrication passages 223b is not particularly limited, and for example, a plurality of axial lubrication passages 223a and radial lubrication passages 223b may be provided at regular intervals in the circumferential direction.

The first vibration generator bearing 21a includes a plurality of first rolling elements 24a, a first retainer 26a that holds the plurality of first rolling elements 24a, and a first outer ring member 28a that is internally fitted to the external gear 4. ,including. The second vibration generator bearing 21b includes a plurality of second rolling elements 24b, a second retainer 26b that holds the plurality of second rolling elements 24b, and a second outer ring member 28b that is internally fitted into the external gear 4. including.

Each of the plurality of first rolling elements 24a has a substantially cylindrical shape, and is provided at intervals in the circumferential direction with the central axis facing in a direction substantially parallel to the direction of the rotation axis R. The first rolling element 24a is rotatably held by the first retainer 26a and rolls on the outer peripheral surface 222c of the first vibrating body 222a. In other words, the inner ring of the first vibrating body bearing 21a is formed integrally with the outer peripheral surface 222c of the first vibrating body 222a. may be provided. The second rolling element 24b is configured similarly to the first rolling element 24a. The plurality of second rolling elements 24b are rotatably held by a second retainer 26b arranged so as to be aligned with the first retainer 26a in the axial direction, and roll on the outer peripheral surface 222d of the second vibrating body 222b. do. In other words, the inner ring of the second vibrating body bearing 21b is formed integrally with the outer peripheral surface 222d of the second vibrating body 222b. may be provided. Henceforth, the 1st rolling element 24a and the 2nd rolling element 24b are also collectively called "rolling element 24." Also, the first retainer 26a and the second retainer 26b are collectively referred to as the "retainer 26".

The first outer ring member 28a surrounds the plurality of first rolling elements 24a. The first outer ring member 28a is flexible and elliptically bent by the vibrating body 222 via the plurality of first rolling elements 24a. The first outer ring member 28a is continuously flexurally deformed according to the shape of the vibration generator 222 when the vibration generator 222 (that is, the vibration generator shaft 22) rotates. The second outer ring member 28b is configured similarly to the first outer ring member 28a. The second outer ring member 28b is formed separately from the first outer ring member 28a. The second outer ring member 28b may be formed integrally with the first outer ring member 28a. Henceforth, the 1st outer ring member 28a and the 2nd outer ring member 28b are also collectively called "outer ring member 28."

The external gear 4 is an annular member having flexibility, and the vibrating body 222, the rolling elements 24 and the outer ring member 28 are fitted inside thereof. The external gear 4 is bent in an elliptical shape by fitting the vibration generator 222, the rolling elements 24, and the outer ring member 28 therein. When the vibrating body 222 rotates, the external gear 4 is continuously flexurally deformed according to the shape of the vibrating body 222 . The external gear 4 includes a first external tooth portion 4a positioned outside the first outer ring member 28a, a second external tooth portion 4b positioned outside the second outer ring member 28b, and a base material 4c. The first external tooth portion 4a and the second external tooth portion 4b are formed on the base material 4c, which is a single base material, and have the same number of teeth.

The first internal gear 6 is an annular member having rigidity, and a first internal tooth portion 6a is formed on the inner periphery thereof. The first internal toothed portion 6a surrounds the first externally toothed portion 4a of the externally toothed gear 4 bent in an elliptical shape, and the first externally toothed portion 6a surrounds the first externally toothed portion 4a in a predetermined region (two regions) near the major axis of the vibrating body 222. It meshes with the tooth portion 4a. The first internal toothing 6a has more teeth than the first external toothing 4a.

The second internal gear 8 is arranged axially side by side (adjacent to) the first internal gear 6 . The second internal gear 8 is a rigid cylindrical member, and a second internal tooth portion 8a is formed on the inner periphery thereof. The second internal toothed portion 8a surrounds the second external toothed portion 4b of the external gear 4 bent in an elliptical shape, and the second external toothed portion 8a surrounds the second external toothed portion 4b in a predetermined region (two regions) in the longitudinal direction of the vibrating body 222. It meshes with the tooth portion 4b. The second internal toothing 8a has the same number of teeth as the second external toothing 4b. Therefore, the second internal gear 8 rotates in synchronization with the rotation of the second external gear 4b and thus the external gear 4. As shown in FIG.

The first internal tooth member 7 includes a first body portion 52 , an encircling portion 54 , a first restricting portion 56 and a first extension portion 58 . In the present embodiment, the first main body portion 52, the first restricting portion 56 and the first extending portion 58 are integrally formed, but may be configured by connecting a plurality of members. The first body portion 52 is an annular member, and the first internal gear 6 is provided on the inner peripheral side thereof. In the present embodiment, the first internal gear 6 and the first body portion 52 are integrally formed. Therefore, the first body portion 52 and the first internal tooth member 7 rotate integrally with the first internal gear 6 . Note that the first internal gear 6 and the first body portion 52 may be formed separately and then joined together.

The surrounding portion 54 is a substantially cylindrical member. The first body portion 52 is spigot-fitted to the surrounding portion 54 and integrated with the surrounding portion 54 by means of bolts (not shown). The surrounding portion 54 extends from the first body portion 52 to the radially outer side of the second internal gear 8 and surrounds the second internal gear 8 and the second internal tooth member 9 .

The first restricting portion 56 extends radially inward from the side of the first body portion 52 opposite to the second internal tooth member 9 . The first restricting portion 56 has the external gear 4 and the outer ring member 28 on its axial inner side (on the same side as between the first external toothed portion 4a and the second externally toothed portion 4b with respect to the first restricting portion 56). and a facing surface 56a facing the retainer 26 in the axial direction. The first restricting portion 56 restricts axial movement of the external gear 4 , the outer ring member 28 and the retainer 26 together with a second restricting portion 66 which will be described later.

The first extending portion 58 extends axially from the radially inner side of the first restricting portion 56 . The first extending portion 58 particularly extends to the radially inner side of the first vibrating body 222a. That is, the first extending portion 58 and the first vibrating body 222a overlap when viewed from the radial direction.

The second internal tooth member 9 includes a second body portion 62 , a cover portion 64 , a second restriction portion 66 and a second extension portion 68 . In the present embodiment, the second main body portion 62, the cover portion 64, the second restriction portion 66 and the second extension portion 68 are integrally formed, but may be configured by connecting a plurality of members. The second body portion 62 is an annular member, and the second internal gear 8 is provided on the inner peripheral side thereof. In this embodiment, the second internal gear 8 and the second main body portion 62 are integrally formed. Therefore, the second body portion 62 and thus the second internal tooth member 9 rotate integrally with the second internal gear 8 . Note that the second internal gear 8 and the second main body portion 62 may be formed separately and then joined together.

The cover portion 64 is a substantially disc-shaped member, and is provided with a driving device in the axial direction so as to close the opening of the second body portion 62 on the side opposite to the first body portion (the left side in FIG. 1). is formed integrally with the second main body portion 62 radially inwardly of the second main body portion 62 so as to close the opening of the flexural mesh gear device 100 on the opposite side (that is, the non-input side) of the side on which the second main body portion 62 is engaged. be. The shaft portion 221 does not pass through the cover portion 64 (that is, the second internal tooth member 9).

The second restricting portion 66 is radially inside the second body portion 62 and axially inside the cover portion 64 (between the first external tooth portion 4a and the second external tooth portion 4b with respect to the cover portion 64). (same side). The second restricting portion 66 has, on its axial inner side (the same side as between the first external toothed portion 4a and the second external toothed portion 4b with respect to the second restricting portion 66), the external gear 4, the outer ring member 28 and the It has a facing surface 66a that faces the retainer 26 in the axial direction. The second restricting portion 66 restricts axial movement of the external gear 4, the outer ring member 28 and the retainer 26 together with the first restricting portion 56 as described above.

The second extension 68 extends axially from the cover portion 64 . The second extending portion 68 particularly extends to the radially inner side of the second vibrating body 222b. That is, the second extending portion 68 and the second vibrating body 222b overlap when viewed from the radial direction.

The first input bearing 30 is arranged between the shaft portion 221 and the first internal tooth member 7 , and the second input bearing 32 is arranged between the shaft portion 221 and the second internal tooth member 9 . Both the first input bearing 30 and the second input bearing 32 have outer diameters smaller than the minimum outer diameter (that is, the minor axis diameter) of the vibrating body 222 . The first internal tooth member 7 and the second internal tooth member 9 rotatably support the shaft portion 221 via the first input bearing 30 and the second input bearing 32 .

Preferably, the first input bearing 30 is arranged between the shaft portion 221 and the first extension 58 of the first internal toothed member 7 and the second input bearing 32 is positioned between the shaft portion 221 and the second internal toothed member. 9 and the second extension 68 . At least one of the first input bearing 30 and the second input bearing 32 is arranged so that at least a portion thereof is positioned radially inside the vibrating body 222 (that is, at least a portion of the vibrating body 222 when viewed in the radial direction). ) are arranged. More preferably, the first input bearing 30 and the second input bearing 32 are positioned entirely inside the vibrating body 222 in the radial direction as shown in the drawing (i.e., as seen from the radial direction, the entirety of the first input bearing 30 and the second input bearing 32 ) are arranged.

The main bearing 16 is arranged between the surrounding portion 54 of the first internal toothed member 7 and the second main body portion 62 of the second internal toothed member 9 so that its axial direction coincides with the rotation axis R. The first internal tooth member 7 supports the second internal tooth member 9 via the main bearing 16 so as to be relatively rotatable.

An oil seal 40 is arranged between the shaft portion 221 of the vibration generator shaft 22 and the first extension portion 58 of the first internal toothed member 7 to surround the first body portion 52 of the first internal toothed member 7 . An O-ring 36 is arranged between the portion 54 and an oil seal 42 between the surrounding portion 54 of the first internal toothed member 7 and the second body portion 62 of the second internal toothed member 9 . As a result, it is possible to prevent the leakage of the lubricant in the flexural meshing gear device 100 .

The operation of the flexural mesh gear device 100 configured as described above will be described. Here, the number of teeth of the first external tooth portion 4a is 100, the number of teeth of the second external tooth portion 4b is 100, the number of teeth of the first internal tooth portion 6a is 102, and the number of teeth of the second internal tooth portion 8a is 100. A case will be described as an example. Also, a case where the second internal gear 8 is connected to the driven member will be described as an example.

When the vibrating body shaft 22 rotates in a state where the first external toothed portion 4a is meshed with the first internal toothed portion 6a at two points in the long axis direction of the elliptical shape, the first external toothed portion 4a and the first external toothed portion 4a are rotated. The meshing position with the first internal tooth portion 6a also moves in the circumferential direction. Since the first external toothed portion 4a and the first internal toothed portion 6a have different numbers of teeth, at this time, the first external toothed portion 4a rotates relative to the first internal toothed portion 6a. Since the first internal gear 6 is in a fixed state, the first external toothed portion 4a rotates by an amount corresponding to the difference in the number of teeth. In other words, the rotation of the vibration generator shaft 22 is significantly decelerated and output to the first external toothed portion 4a. The reduction ratio is as follows.
Reduction ratio=(number of teeth of first external tooth 4a-number of teeth of first internal tooth 6a)/number of teeth of first external tooth 4a=(100-102)/100
=-1/50

Since the second external toothed portion 4b is integrally formed with the first external toothed portion 4a, it rotates integrally with the first external toothed portion 4a. Since the second external toothed portion 4b and the second internal toothed portion 8a have the same number of teeth, relative rotation does not occur, and the second external toothed portion 4b and the second internal toothed portion 8a rotate integrally. Therefore, the same rotation as the rotation of the first external toothed portion 4a is output to the second internal toothed portion 8a. As a result, it is possible to take out an output from the second internal gear 8 by reducing the rotation of the vibrating body shaft 22 to -1/50.

Next, the effects of this embodiment will be described. According to the present embodiment, first input bearing 30 and second input bearing 32 have outer diameters smaller than the minimum outer diameter of vibrating body 222 . As a result, the first input bearing 30 and the second input bearing 32 can be made small while the desired torque is achieved by relatively increasing the outer diameter of the vibrating body 222 . In other words, the moment of inertia and friction loss can be reduced while achieving the desired torque.

In addition, since the first input bearing 30 and the second input bearing 32 have outer diameters smaller than the minimum outer diameter of the vibrating body 222, at least a part of the first input bearing 30 and the second input bearing 32 have diameters. It is possible to make the bending gear device 100 compact in the axial direction by arranging it so as to overlap the vibrating body 222 in the direction. The axial compactness reduces the moment of inertia.

Preferably, the first input bearing 30 is located between the first extension 58 and the shank 221 and the second input bearing 32 is located between the second extension 68 and the shank 221 . The first extension portion 58 and the second extension portion 68 extend radially inward of the vibrating body 222 . Therefore, each input bearing is arranged radially inside the vibrating body 222 , that is, at a position overlapping the vibrating body 222 when viewed from the radial direction. This makes the flexural mesh gear system 100 more compact in the axial direction and further reduces the moment of inertia.

Further, according to the present embodiment, shaft portion 221 has hollow portion 221c. As a result, the weight of the shaft portion 221 is reduced, and the moment of inertia is reduced.

Further, according to the present embodiment, the connecting portion 223 has the axial lubrication passage 223a and the radial lubrication passage 223b. As a result, the length of the path from the hollow portion 221c to each bearing or the like is shortened, so that, for example, when lubricant is enclosed in the hollow portion 221c, the lubricant is easily supplied to each bearing or the like. As a result, the service life of the flexural mesh gear device 100 can be extended.

Further, according to the present embodiment, the first body portion 52, the first restricting portion 56 and the first extending portion 58 of the first internal tooth member 7 are integrally formed. Further, the second main body portion 62, the cover portion 64, the second restricting portion 66 and the second extending portion 68 of the second internal tooth member 9 are integrally formed. As a result, the first internal tooth member 7 and the second internal tooth member 9, as well as the flexural meshing gear device 100, can be made relatively thin in the axial direction. As a result, the moment of inertia is reduced.

(Second embodiment)
FIG. 2 is a cross-sectional view showing a flexural mesh gear device 100 according to a second embodiment. Focus on the differences from Figure 1.

In the present embodiment, the bending gear device 100 further includes a first restricting member 12 and a second restricting member 14 . The first restricting member 12 is a flat ring-shaped member, and has a surface 12a on the inner side in the axial direction (on the same side as between the first external toothed portion 4a and the second externally toothed portion 4b with respect to the first restricting member 12). is arranged to face the external gear 4, the first outer ring member 28a and the first retainer 26a. The second restricting member 14 is a flat ring-shaped member, and has a surface 14a on the inner side in the axial direction (the same side as between the first external toothed portion 4a and the second externally toothed portion 4b with respect to the second restricting member 14). is arranged to face the external gear 4, the second outer ring member 28b and the second retainer 26b.

In the first internal tooth member 7, the first body portion 52 is formed separately from the first restricting portion 56 and the first extending portion 58, and the first body portion 52 and the first extending portion 58 are integrated with each other by bolts. Similarly, in the second internal tooth member 9, the second main body portion 62 is formed separately from the cover portion 64, the second restricting portion 66 and the second extending portion 68, and these are integrated by bolts.

The first restricting portion 56 of the first internal tooth member 7 restricts axial movement of the first restricting member 12, and the second restricting portion 66 of the second internal tooth member 9 restricts axial movement of the second restricting member 14. to regulate. That is, the first restricting portion 56 and the second restricting portion 66 restrict axial movement of the external gear 4, the outer ring member 28, and the retainer 26 via the first restricting member 12 and the second restricting member 14. .

According to the flexural mesh gear device 100 according to the present embodiment, it is possible to obtain the same effects as those of the first embodiment. In addition, according to the bending gear device 100 according to the present embodiment, the first main body portion 52 of the first internal tooth member 7, the first restricting portion 56 and the first extending portion 58 are separated from each other. Since it is formed, the shape is relatively simple compared to the case where they are integrally formed, and processing is easy. Similarly, since the second body portion 62 of the second internal toothed member 9, the cover portion 64, the second restricting portion 66 and the second extending portion 68 are formed as separate bodies, when they are integrally formed Compared to , the shape is relatively simple, so processing is easy.

The flexural mesh gear device according to the embodiment has been described above. Those skilled in the art will understand that these embodiments are merely examples, and that various modifications can be made to combinations of each component and each treatment process, and such modifications are also within the scope of the present invention. By the way.

4 external gear 6 first internal gear 7 first internal tooth member 8 second internal gear 9 second internal tooth member 22 vibrator shaft 30 first input bearing 32 second input bearing , 100 flexural mesh gear device, 221 shaft, 222 vibrating body.

Claims (6)

a vibration generator shaft having a vibration generator; an external gear that is flexurally deformed by the vibration generator; a first internal gear that meshes with the external gear; A second internal gear that is arranged and meshes with the external gear, a first internal gear that rotates integrally with the first internal gear, and a second internal gear that integrally rotates with the second internal gear. A flexural mesh gear system comprising a tooth member,
The vibration generator shaft has a shaft portion that rotates integrally with the vibration generator,
The flexure mesh gear device further comprises:
a first input bearing disposed between the shaft portion and the first internal tooth member;
a second input bearing disposed between the shaft portion and the second internal tooth member;
the outer diameters of the first input bearing and the second input bearing are smaller than the outer diameter of the vibration generator;
the vibration generator shaft has a connecting portion that connects the shaft portion and the vibration generator;
A flexural mesh gear device, wherein the connecting portion has an axial lubrication passage penetrating in the axial direction, and a radial lubrication passage communicating between the axial lubrication passage and the outer periphery of the vibration generator. The first internal tooth member has a first extending portion extending radially inward of the vibrating body,
2. A flexural mesh gear device according to claim 1, wherein said first input bearing is arranged between said shaft portion and said first extension portion. the second internal tooth member has a second extending portion extending radially inward of the vibrating body;
3. A flexural mesh gear device according to claim 2, wherein said second input bearing is arranged between said shaft portion and said second extension portion. The external gear has a first external tooth portion that meshes with the first internal gear and a second external tooth portion that meshes with the second internal gear,
A first vibration generator bearing arranged between the vibration generator and the first external tooth, and a second vibration generator bearing arranged between the vibration generator and the second external tooth. and further comprising
2. The radial lubrication passage communicates with the outer circumference of the vibration generator between the rolling element of the first vibration generator bearing and the rolling element of the second vibration generator bearing. 4. A flexible mesh gear device according to any one of 3. The shaft portion penetrates the first internal tooth member and protrudes to the outside, and has a hollow portion,
5. The flexural mesh gear device according to claim 1, wherein the protruding side end of said hollow portion is closed and the non-protruding side end of said hollow portion is open. the second internal tooth member closes the non-input side opening of the flexural mesh gear device;
6. The flexural mesh gear unit according to claim 1, wherein the shaft portion does not pass through the second internal tooth member.

Images