CN110762169B

CN110762169B - Flexible meshing gear device

Info

Publication number: CN110762169B
Application number: CN201910203489.5A
Authority: CN
Inventors: 石塚正幸; 南云稔也; 石田悠朗; 刘媛媛
Original assignee: Sumitomo Heavy Industries Ltd
Current assignee: Sumitomo Heavy Industries Ltd
Priority date: 2018-07-25
Filing date: 2019-03-18
Publication date: 2023-05-02
Anticipated expiration: 2039-03-18
Also published as: JP7034026B2; CN110762169A; JP2020016278A; DE102019117853A1

Abstract

The purpose of the present invention is to provide a flexible meshing gear device using a roller bearing as a starter bearing, wherein the occurrence of skew in the rollers can be suppressed and appropriate intervals can be ensured between a plurality of rollers that roll within a predetermined range. The flex-meshing gear device includes a space ensuring member that rotates integrally with the oscillating body. The oscillating body bearing has a plurality of rollers including a roller sandwiched between a 1 st rolling surface on the inner peripheral side and a 2 nd rolling surface on the outer peripheral side in a relaxed state and a roller sandwiched between the 1 st rolling surface on the inner peripheral side and the 2 nd rolling surface on the outer peripheral side in a tight state, and the gap securing member is a member that applies a braking force to the revolution movement of the 1 st roller in the direction of the 2 nd roller to secure a gap between the 1 st roller and the 2 nd roller, and is opposed to both ends of the roller in the axial direction, in the case where the roller in the relaxed state and the roller in the tight state adjacent to each other among the plurality of rollers are referred to as the 1 st roller and the 2 nd roller, respectively.

Description

Flexible meshing gear device

The present application claims priority based on japanese patent application No. 2018-138939 filed on 25 th 7 th 2018. The entire contents of this japanese application are incorporated by reference into the present specification.

Technical Field

The present invention relates to a flex engagement gear device.

Background

Patent document 1 discloses a flex-meshing gear device in which an external gear having flexibility meshes with an internal gear having rigidity to transmit rotational motion. In this flex-meshing gear device, the wave generator for flexing the external gear includes a rigid pin (corresponding to the oscillating body) and a wave bearing (corresponding to the oscillating body bearing). The rigid pin has an elliptical outer peripheral surface, which is embedded in the external gear via a wave bearing, and deforms the external gear into an elliptical shape. The wave bearing is a full ball bearing. The plurality of rolling elements (balls) of the wave bearing include rolling elements sandwiched between an inner ring and an outer ring in a tight state and rolling elements sandwiched between the inner ring and the outer ring in a loose state.

The flex-mesh gear device of patent document 1 also discloses a space ensuring member that applies a braking force to rolling elements so as to ensure a space between a plurality of rolling elements sandwiched in a tight state between an inner ring and an outer ring.

Patent document 1: international publication No. 2018/025296

In the flexible meshing gear device of patent document 1, a braking force is applied to the revolution motion of the rolling elements (balls) by the interval ensuring member. However, when such a space ensuring member is used in a roller bearing, there arises a problem that the rollers are skewed (inclined) due to braking force applied from one side. If skew occurs, normal rolling of the rollers is blocked, and the life of the oscillating body bearing is shortened.

Disclosure of Invention

The purpose of the present invention is to prevent the rollers from being skewed and to ensure proper spacing between the rollers in a flexible meshing gear device using a roller bearing as a vibrator bearing.

A flexible meshing gear device according to the present invention includes: an internal gear; an external gear engaged with the internal gear; a vibration starting body for deforming the external gear; and a starting body bearing disposed between the starting body and the external gear, wherein the flexible meshing gear device further includes a space ensuring member integrally rotating with the starting body, the starting body includes a plurality of rollers including a roller interposed between a 1 st rolling surface on an inner peripheral side and a 2 nd rolling surface on an outer peripheral side in a relaxed state and a roller interposed between the 1 st rolling surface on the inner peripheral side and the 2 nd rolling surface on the outer peripheral side in a tight state, and the space ensuring member is a member for applying a braking force to a revolution movement of the 1 st roller in a direction toward the 2 nd roller to ensure a space between the 1 st roller and the 2 nd roller, and the space ensuring member is opposed to both end portions of the roller in an axial direction when the roller in the relaxed state and the roller in the tight state of the plurality of rollers are referred to as the 1 st roller and the 2 nd roller, respectively.

Another flexible meshing gear device according to the present invention includes: an internal gear; an external gear engaged with the internal gear; a vibration starting body for deforming the external gear; and a vibrator bearing disposed between the vibrator and the external gear, wherein the flexible meshing gear device further includes a space ensuring member integrally rotating with the vibrator, the vibrator has a plurality of rollers including a roller interposed between a 1 st rolling surface on an inner peripheral side and a 2 nd rolling surface on an outer peripheral side in a relaxed state and a roller interposed between the 1 st rolling surface on the inner peripheral side and the 2 nd rolling surface on the outer peripheral side in a tight state, and the space ensuring member is a member for applying a braking force to a revolution movement of the 1 st roller in a direction toward the 2 nd roller to ensure a space between the 1 st roller and the 2 nd roller, and the space ensuring member is opposed to a range including a center in an axial direction of the roller when the roller in the relaxed state and the roller in the tight state of the plurality of rollers are referred to as the 1 st roller and the 2 nd roller, respectively.

According to the present invention, the following effects can be obtained: in a flexible meshing gear device using a roller bearing as a vibrator bearing, skew of rollers can be suppressed and an appropriate interval between the rollers can be ensured.

Drawings

Fig. 1 is a cross-sectional view showing a flex-meshing gear device according to a first embodiment of the present invention.

Fig. 2 is a view of the gear mechanism of the first embodiment as seen from the axial direction.

Fig. 3 is an enlarged view showing the periphery of the interval securing member according to the first embodiment.

Fig. 4 is a cross-sectional view showing a flex-meshing gear device according to a second embodiment of the present invention.

Fig. 5 is an enlarged view showing the periphery of the interval securing member according to the second embodiment.

Fig. 6 is a cross-sectional view showing a flex-meshing gear device according to a third embodiment of the present invention.

Fig. 7 is an enlarged view showing the periphery of the interval securing member according to the third embodiment.

Fig. 8 is a cross-sectional view showing a flex engagement gear device according to a fourth embodiment of the present invention.

Fig. 9 is a view of the gear mechanism of the fourth embodiment as seen from the axial direction.

Fig. 10 is an enlarged view showing the periphery of the interval securing member according to the fourth embodiment.

In the figure: 1. 1A, 1B, 1C-flex-mesh gear device, 10-oscillating body shaft, 10A-oscillating body, 12-external gear, 15-oscillating body bearing, 15A, 15 Aa-roller, 22 g-1 st internal gear, 23 g-2 nd internal gear, 19 a-19 h, 19 n-19 q-interval securing member, S1, S2-rolling surface.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present specification, unless otherwise specified, the axial direction, the radial direction, and the circumferential direction refer to respectively: along the direction (axial direction) of the rotation axis O1, the direction (radial direction) perpendicular to the rotation axis O1, and the rotation direction (circumferential direction) around the rotation axis O1.

(first embodiment)

Fig. 1 is a cross-sectional view showing a flex-meshing gear device according to a first embodiment of the present invention. Fig. 2 is a view of the gear mechanism of the first embodiment as seen from the axial direction. Fig. 2 schematically shows the starting body shaft 10, the external gear 12, the starting body bearing 15, and the 1 st internal gear 22g, and in this figure, only the starting body shaft 10 shows a cross section cut at the interval securing member 19 a. Fig. 3 is an enlarged view showing the periphery of the interval securing member according to the first embodiment.

As shown in fig. 1, the flexible meshing gear device 1 according to the first embodiment includes a vibrator shaft 10, a flexible outer gear 12, a 1 st inner gear 22g and a 2 nd inner gear 23g meshing with the outer gear 12, a vibrator bearing 15, and space ensuring members 19a to 19d. The flexible meshing gear device 1 further includes a 1 st housing 22, an internal gear member 23 having a 2 nd internal gear 23g, a 2 nd housing 24, a 1 st cover 26, a 2 nd cover 27,

bearings

31 and 32, and a main bearing 33. The flexible meshing gear device 1 further includes

spacer rings

35a, 35b, 36a, 36b, 37a, 37b. In addition, the

spacer rings

36a, 37a and 37b may be eliminated to increase the axial length of the roller 15A.

The vibrator shaft 10 has a hollow shaft shape, and includes: a vibration starting body 10A having an elliptical cross section perpendicular to the rotation axis O1; and

shaft portions

10B and 10C provided on both sides in the axial direction of the oscillation starting body 10A and having a circular outer shape in a cross section perpendicular to the rotation axis O1. The ellipse need not be geometrically strictly elliptical, but includes a substantially elliptical shape. The vibrator shaft 10 rotates about a rotation axis O1.

The external gear 12 is a flexible cylindrical metal, and has teeth provided on its outer periphery.

The 1 st internal gear 22g and the 2 nd internal gear 23g are axially aligned and meshed with the external gear 12. The 1 st internal gear 22g is constituted by providing teeth on a part of the inner periphery of the 1 st casing 22. The 2 nd internal gear 23g is formed by providing teeth on a part of the inner periphery of the internal gear member 23.

The oscillating body bearing 15 has a plurality of rolling bodies (i.e., a plurality of rollers 15A) and an outer ring 15B.

The oscillating body bearing 15 is a full-load roller bearing that does not have a retainer that moves in the circumferential direction together with the plurality of rollers 15A and that retains the intervals between the plurality of rollers 15A. The number of rollers 15A may be increased to reduce the load borne by one roller 15A corresponding to omission of the retainer, so that the life of the oscillating body bearing 15 can be prolonged. The oscillating body bearing 15 is disposed between the oscillating body 10A and the external gear 12. The plurality of rollers 15A roll with the outer peripheral surface of the oscillating body 10A and the inner peripheral surface of the outer ring 15B as rolling surfaces S1 and S2 (see fig. 2 and 3). The rolling surface may also be referred to as a raceway surface. The structure of the vibration-generating body bearing 15 is not limited to this, and the vibration-generating body bearing 15 may have an inner ring formed separately from the vibration-generating body 10A. Further, the outer ring 15B may not be provided, and the inner peripheral surface of the outer gear 12 may be a rolling surface. The oscillating body bearing 15 does not have to have a retainer at all, and a retainer may be provided in a part of the range.

The plurality of rollers 15A include a 1 st row of rollers 15A that move along the inner circumference of the 1 st internal gear 22g and a 2 nd row of rollers 15A that move along the inner circumference of the 2 nd internal gear 23g. Each roller 15A of the first embodiment has a cylindrical shape, and has convex portions at both end portions in the axial direction thereof to suppress excessive concentration of stress on the edges of the roller 15A. The convex part means: the curvature of the outer peripheral surfaces of the axial ends of the roller 15A is gradually set away from the rolling surfaces S1 and S2. The axial direction of the roller 15A means: along the direction of the central axis of rotation of the roller 15A. In addition, the roller of the present invention is a concept including a needle roller.

The 1 st casing 22 and the 2 nd casing 24 cover the outer peripheral side of the portion of the 1 st internal gear 22g and the 2 nd internal gear 23g meshing with the external gear 12. The 2 nd casing 24 is coupled to the 1 st casing 22 integrated with the 1 st internal gear 22 g. The 2 nd casing 24 rotatably supports the internal gear member 23 with respect to the 2 nd casing 24 via a main bearing 33. The main bearing 33 is, for example, a cross roller bearing.

The 1 st cover 26 is coupled to the 1 st housing 22 and covers the outer peripheral portion of the oscillating body shaft 10 on the opposite side to the load. The opposite side of the load refers to: on the opposite side of the axial direction from the side to which the driven member is coupled.

The 1 st cover 26 rotatably supports the shaft portion 10B of the oscillating body shaft 10 with respect to the 1 st cover 26 via a bearing 31. The 2 nd cover 27 is coupled to the internal gear member 23 and covers the load-side outer peripheral portion of the oscillating body shaft 10. The load side means: one side of the axial driven member is connected. The 2 nd cover 27 rotatably supports the shaft portion 10C of the oscillating body shaft 10 with respect to the 2 nd cover 27 via a bearing 32. The

bearings

31, 32 are, for example, ball bearings.

The spacer rings 35a and 35B are disposed on both sides of the external gear 12 and the outer ring 15B in the axial direction, respectively, and suppress axial displacement of the external gear 12 and the outer ring 15B.

The spacer rings 36a and 36b are disposed on both sides in the axial direction of the plurality of rollers 15A in the 1 st row of the oscillating body bearing 15, respectively, and suppress the plurality of rollers 15A in the 1 st row from moving in the axial direction. The spacer rings 37a and 37b are disposed on both sides in the axial direction of the plurality of rollers 15A in the 2 nd row of the oscillating body bearing 15, respectively, and suppress the plurality of rollers 15A in the 2 nd row from moving in the axial direction.

< description of deceleration action >

When a rotational motion from a motor (not shown) or the like is input to the vibrator shaft 10 to rotate it, the motion of the vibrator 10A is transmitted to the external gear 12. As shown in fig. 2, the oscillating body 10A is fitted inside the external gear 12 via the oscillating body bearing 15, and the external gear 12 is deflected into an elliptical shape having a major axis portion and a minor axis portion by being restricted by the outer peripheral shape of the oscillating body 10A. Further, the external gear 12 meshes with the fixed 1 st internal gear 22g at the long shaft portion thereof. Therefore, the external gear 12 does not rotate at the same rotation speed as the rotation speed of the oscillating body 10A, and the oscillating body 10A relatively rotates inside the external gear 12. Then, with this relative rotation, the external gear 12 is deformed so as to move in the circumferential direction in the major axis position and the minor axis position. The period of this deformation is proportional to the rotation period of the vibrator shaft 10.

When the external gear 12 is deformed by bending, the long axis position thereof moves, and therefore, the meshing position of the external gear 12 and the 1 st internal gear 22g changes in the rotation direction. Here, when the number of teeth of the external gear 12 is 100 and the number of teeth of the 1 st internal gear 22g is 102, the meshing teeth of the external gear 12 and the 1 st internal gear 22g are offset for each rotation of the meshing position, and the external gear 12 is rotated (rotated). If the number of teeth is set as described above, the rotational motion of the oscillating body shaft 10 is decelerated at a reduction ratio of 100:2 and then transmitted to the external gear 12.

On the other hand, since the external gear 12 is also meshed with the 2 nd internal gear 23g, the meshing position of the external gear 12 and the 2 nd internal gear 23g also changes in the rotation direction with the rotation of the vibrator shaft 10. Here, if the number of teeth of the 2 nd internal gear 23g is the same as the number of teeth of the external gear 12, the external gear 12 and the 2 nd internal gear 23g do not rotate relatively, and the rotational motion of the external gear 12 is transmitted to the 2 nd internal gear 23g at a reduction ratio of 1:1. In this way, the rotational motion of the vibrator shaft 10 is decelerated at a reduction ratio of 100:2, and then output to the driven member from the internal gear member 23 and the 2 nd cover 27, for example.

Detailed description of the interval ensuring Member and roller bearing

As shown in fig. 2, the plurality of rollers 15A of the vibrator bearing 15 are different in magnitude in load received in a range W1 near the long axis portion of the vibrator 10A and a range W2 near the short axis portion of the vibrator 10A. In the range W1, the rollers 15A receive a large load from the outer peripheral surface of the starting body 10A and the inner peripheral surface of the outer ring 15B so as to be sandwiched therebetween in a compact state. Hereinafter, this roller 15A is also referred to as a compact roller 15A. In the range W2, the roller 15A does not receive a large load from the outer peripheral surface of the starting body 10A and the inner peripheral surface of the outer ring 15B, sandwiching them in a relaxed state. Hereinafter, this roller 15A is also referred to as a loose roller 15A.

In fig. 2, the roller 15A in the compact state is shown in white, and the roller 15A in the relaxed state is shown in dark. The roller 15A in a tight state rolls in a state of being in contact (line contact) with the two rolling surfaces S1, S2 on the inner peripheral side and the outer peripheral side. On the other hand, the loose roller 15A is in a freely rolling state with a gap between the inner peripheral side and the outer peripheral side of the roller and the two rolling surfaces S1 and S2. The moving direction of the plurality of rollers 15A can also be switched between the clockwise direction and the counterclockwise direction in fig. 2, depending on the rotating direction of the oscillating body shaft 10.

The gap securing members 19a to 19d are made of, for example, rubber, resin, or the like (that is, a material having a young' S modulus lower than that of the material (steel) constituting the rolling surface S1 on which the roller 15A rolls. The interval securing members 19a to 19d are attached to the oscillating body 10A and rotate together with the oscillating body 10A. That is, the plurality of rollers 15A rotate by the portions where the interval securing members 19a to 19d are arranged. The interval securing members 19a to 19d are bonded and fixed to grooves 10ma to 10md (see fig. 3) provided on the outer peripheral surface of the oscillating body 10A, for example.

The interval securing members 19a to 19d are disposed at a plurality of locations (for example, four locations) between the range W1 and the range W2, and more specifically, at a plurality of locations (for example, four locations) each including both end sections in the circumferential direction of the range W2 (refer to fig. 2). The interval securing members 19a are shown in fig. 2, but other interval securing members 19b to 19d are also arranged at the same position in the circumferential direction.

As shown in fig. 3, the

gap securing members

19a, 19b are opposed to (the outer periphery of) both ends in the axial direction of the row 1 roller 15A in the radial direction. The

gap ensuring members

19a and 19b are provided so as to protrude radially beyond the outer peripheral surface (rolling surface S1) of the vibration body 10A so as to be in contact with (the outer periphery of) both end portions of the roller 15A when the roller 15A passes therethrough. The

interval securing members

19a and 19b are provided so as to protrude so as to contact with the convex surface portion of the roller 15A away from the rolling surface S1. The two axial end portions of the roller 15A may be regarded as portions on both sides of the portion that axially bisects the roller 15A, and the "opposite end portions" may be formed so as to be opposite to at least a part of the two end portions. That is, the structure facing the both end portions includes a structure facing a range excluding both end points. The axial direction of the roller 15A almost coincides with the axial direction of the rotation shaft O1.

The

interval securing members

19a, 19b have a shape symmetrical to each other on one side and the other side in the axial direction with the center of the roller 15A of the 1 st row interposed therebetween, and are arranged symmetrical to each other. In addition, these symmetries may be structures that are not completely symmetrical, or may be asymmetric structures.

The configuration of the

space ensuring members

19c and 19d is the same as that of the

space ensuring members

19a and 19b except that the space ensuring members are arranged corresponding to the rollers 15A of the 2 nd row.

< action of interval ensuring means >)

First, it is assumed that the vibrator shaft 10 continuously rotates in the clockwise direction in fig. 2. At this time, the plurality of rollers 15A move in the counterclockwise direction with respect to the oscillating body 10A. That is, the plurality of rollers 15A move from the range W2 to which the large load is not applied to the range W1 to which the large load is applied, or conversely, from the range W1 to which the large load is applied to the range W2 to which the large load is not applied, respectively, depending on the positions thereof.

The roller 15A moving from the range W2 to the range W1 receives braking forces from the interval securing members 19a to 19d during movement. Since the roller 15A is in a state of being freely scrolled between the rolling surfaces S1, S2 while being in a relaxed state in the range W2, the roller 15A is delayed from entering the range W1 by the braking force. Thereby, a space is ensured between the roller 15A and the roller 15A that has first entered the range W1. In other words, when the one roller 15A in a relaxed state and the one roller 15A in a compact state adjacent to each other are referred to as the 1 st roller and the 2 nd roller, respectively, the interval securing members 19a to 19d apply braking force to the revolution motion of the 1 st roller in the direction of the 2 nd roller. Thereby, a gap is ensured between the 1 st roller and the 2 nd roller.

When braking force is applied to the roller 15A from the interval securing members 19a to 19d, the interval securing members 19a to 19d apply braking force from both end portions in the axial direction of the roller 15A. This suppresses skew of the roller 15A.

Further, since the roller 15A entering the range W1 rolls in contact with the inner and outer rolling surfaces S1, S2, the roller 15A entering the range W1 moves within the range W1 with a gap maintained between the roller 15A and the preceding roller 15A. By securing the interval, in the range W1 where a large load is generated, the adjacent rollers 15A can be prevented from rubbing against each other with a large resistance, and the fatigue life of the oscillating body bearing 15 can be prolonged. When a large load is applied to the roller 15A that is tilted, the roller 15A and the rolling surfaces S1 and S2 deteriorate. However, in the present embodiment, since the occurrence of skew can be suppressed, the occurrence of degradation of the roller 15A and the rolling surfaces S1 and S2 can be suppressed, and the fatigue life of the oscillating body bearing 15 can be prolonged.

Thereafter, when the roller 15A moves from the range W1 to the range W2, the roller 15A is allowed to roll freely between the rolling surfaces S1 and S2, and the distance between the roller 15A and the preceding roller 15A is narrowed and moves in the range W2.

Even if the vibrator shaft 10 rotates irregularly in the clockwise direction and the counterclockwise direction, the interval securing members 19a to 19d act on the rollers 15A moving between the range W1 and the range W2 as well, so that the intervals between the plurality of rollers 15A are properly secured in the range W1. When braking force is applied to the roller 15A from the interval securing members 19a to 19d, the roller 15A is prevented from being skewed.

As described above, according to the flex-mesh gear device 1 of the first embodiment, the interval securing members 19a to 19d that integrally rotate with the oscillating body 10A are provided. When one roller 15A in a relaxed state and one roller 15A in a tight state, which are adjacent to each other, of the plurality of rollers 15A of the oscillating body bearing 15 are referred to as a 1 st roller and a 2 nd roller, respectively, the interval securing members 19a to 19d apply braking force to the revolution motion of the 1 st roller in the direction of the 2 nd roller. This ensures that the intervals between the rollers 15A are ensured in the range W1. The gap securing members 19a to 19d are disposed so as to face both ends of the roller 15A in the axial direction (so as to face each other in the radial direction), and can suppress the roller 15A from being skewed when a braking force is applied. Therefore, in the range W1 in which the load is applied to the rollers 15A, the plurality of rollers 15A can be suppressed from colliding with each other, and the rollers 15A can be suppressed from being skewed, so that the fatigue life of the oscillating body bearing 15 can be prolonged.

In the flexible meshing gear device 1 according to the first embodiment, the space ensuring members 19a to 19d are disposed at positions facing the outer peripheral surface of the end portion of the roller 15A on the rolling surface S1 on which the roller 15A rolls, and the young 'S modulus thereof is smaller than the young' S modulus of the rolling surface. According to this structure, a stable braking force can be applied to the roller 15A so that the roller 15A does not skew. Further, when the gap ensuring members 19a to 19d are in contact with the roller 15A, deterioration of the roller 15A due to friction is less likely to occur.

In the flexible meshing gear device 1 according to the first embodiment, the space securing members 19a to 19d protrude further toward the space where the roller 15A rolls than the rolling surface S1. According to this configuration, a stable braking force can be applied from the interval securing members 19a to 19d so that the roller 15A does not skew.

Further, according to the flexspline gear 1 of the first embodiment, the roller 15A has a convex surface portion that is not in contact with the rolling surface S1, and the space ensuring members 19a to 19d are in contact with the convex surface portion. According to this configuration, the stress concentration on the edge of the roller 15A can be suppressed by the convex portion, and even if there is a convex portion, the braking force can be applied to the roller 15A by the space ensuring members 19a to 19d and the occurrence of skew can be suppressed.

(second embodiment)

Fig. 4 is a cross-sectional view showing a flex-meshing gear device according to a second embodiment of the present invention. Fig. 5 is an enlarged view showing the periphery of the interval securing member according to the second embodiment.

The flex-meshing gear device 1A of the second embodiment is different from the first embodiment mainly in the

distance securing members

19e, 19f, and other constituent elements are the same as those of the first embodiment. Therefore, the same components are denoted by the same reference numerals, and detailed description thereof will be omitted.

The

interval securing members

19e and 19f are attached to the oscillating body 10A and rotate together with the oscillating body 10A. The

gap securing members

19e and 19f are bonded and fixed to grooves 10me and 10mf (fig. 5) provided in the oscillating body 10A, for example. The arrangement of the

interval securing members

19e, 19f in the axial direction is the same as that of the interval securing members 19a to 19d (refer to fig. 2) of the first embodiment.

The

space ensuring members

19e and 19f are made of, for example, rubber, resin, or the like (i.e., a material having a young' S modulus lower than that of the rolling surface S1 (steel) on which the roller 15A rolls).

The

gap ensuring members

19e and 19f are disposed so as to face the range including the center in the axial direction of the outer peripheral surface of the roller 15A. Specifically, the

gap securing members

19e and 19f are opposed to the central range in the axial direction of the outer peripheral surface of the roller 15A in the radial direction. Further, the

interval securing members

19e, 19f are provided to protrude further in the radial direction than the outer peripheral surface (rolling surface S1, refer to fig. 5) of the vibration body 10A so as to be in contact with the outer peripheral surface of the roller 15A when the roller 15A passes therethrough.

The

gap securing members

19e and 19f may have a curvature in the axial direction corresponding to the convex surface portion of the roller 15A on the surface facing the roller 15A, or may be configured to be in surface contact with the outer peripheral surface of the roller 15A by being deflected. The

gap securing members

19e and 19f may be provided in a range facing only the central portion of the roller 15A other than the both end portions in the axial direction.

As in the first embodiment, the

gap ensuring members

19e and 19f contact the roller 15A moving from the range W2 (see fig. 2) to the range W1, and apply a braking force to the roller 15A, thereby ensuring a gap between the roller 15A entering the range W1 and the preceding roller 15A. Further, when braking force is applied, the

gap ensuring members

19e and 19f contact the range including the center in the axial direction of the roller 15A, so that the roller 15A can be prevented from being skewed.

As described above, according to the flexible meshing gear device 1A of the second embodiment, the skew of the rollers 15A can be suppressed and the intervals between the plurality of rollers 15A can be ensured in the range W1. Therefore, the fatigue life of the oscillating body bearing 15 can be prolonged.

Further, according to the flexible meshing gear device 1A of the second embodiment, the

space ensuring members

19e, 19f are arranged so as to face the range including the center in the axial direction of the roller 15A. Therefore, when the

gap ensuring members

19e and 19f contact the roller 15A, the roller 15A can be prevented from being skewed. Further, compared with the configuration of the first embodiment, the number of parts of the

space ensuring members

19e and 19f can be reduced, and the number of assembly steps of the

space ensuring members

19e and 19f can be reduced.

(third embodiment)

Fig. 6 is a cross-sectional view showing a flex-meshing gear device according to a third embodiment of the present invention. Fig. 7 is an enlarged view showing the periphery of the interval securing member according to the third embodiment.

The flex-meshing gear device 1B of the third embodiment is different from the first embodiment mainly in the

distance securing members

19g, 19h, and other constituent elements are the same as those of the first embodiment. Therefore, the same components are denoted by the same reference numerals, and detailed description thereof will be omitted.

In the roller 15Aa of the third embodiment, the area of the convex surface portion having curvature at the end in the axial direction is narrow in the outer shape of the cross section taken along the central axis, and the surface in contact with the oscillating body 10A has a linear shape in the same cross section. The roller 15Aa of the third embodiment may have the same shape as the roller 15A of the first embodiment.

The

gap securing members

19g, 19h are made of, for example, rubber or resin (i.e., a material having a young' S modulus lower than that of the rolling surface S1 (steel) on which the rollers 15Aa roll). The

interval securing members

19g, 19h are attached to the oscillating body 10A and rotate together with the oscillating body 10A. The

gap securing members

19g and 19h are bonded and fixed to grooves 10mg and 10mh (see fig. 7) provided in the oscillating body 10A, for example. The arrangement of the

interval securing members

19g, 19h in the circumferential direction is the same as that of the interval securing members 19a to 19d (refer to fig. 2) of the first embodiment.

The

gap ensuring members

19g and 19h of the third embodiment are disposed so as to be opposed to the entire region in the axial direction of the roller 15Aa in the radial direction. The

gap ensuring members

19g, 19h protrude radially more than the outer peripheral surface of the vibrator 10A, and contact almost the entire area in the axial direction of the roller 15Aa when the roller 15Aa passes therethrough. Specifically, the

gap ensuring members

19g and 19h are in contact with a central portion of the roller 15Aa in the axial direction, a partial range of one end portion in the axial direction, and a partial range of the other end portion except for edge portions of both ends of the roller 15Aa distant from the rolling surface S1.

By adopting the above-described configuration, as in the first embodiment, the

gap ensuring members

19g, 19h are brought into contact with the roller 15Aa moving from the range W2 (refer to fig. 2) to the range W1, and apply a braking force to the roller 15Aa, thereby ensuring a gap between the roller 15Aa entering the range W1 and the preceding roller 15 Aa. When braking force is applied, the

gap ensuring members

19g and 19h contact the axial center and both ends of the roller 15Aa, and therefore, the roller 15Aa can be prevented from being skewed.

As described above, according to the flexible meshing gear device 1B of the third embodiment, the skew of the rollers 15Aa can be suppressed, and the intervals between the plurality of rollers 15Aa can be ensured in the range W1. Therefore, the fatigue life of the oscillating body bearing 15 can be prolonged.

Further, according to the flexible meshing gear device 1B of the third embodiment, the

space ensuring members

19g, 19h are arranged so as to face the entire area in the axial direction of the roller 15 Aa. Therefore, when the

gap ensuring members

19g, 19h contact the roller 15Aa, the roller 15Aa can be prevented from being skewed. Further, compared with the configuration of the first embodiment, the number of parts of the

gap securing members

19g and 19h can be reduced, and the number of assembly steps of the

gap securing members

19g and 19h can be reduced.

(fourth embodiment)

Fig. 8 is a cross-sectional view showing a flex engagement gear device according to a fourth embodiment of the present invention. Fig. 9 is a view of the gear mechanism of the fourth embodiment as seen from the axial direction. Fig. 9 schematically shows the oscillating body shaft 10, the external gear 12, the oscillating body bearing 15, and the 1 st internal gear 22g, and in this figure, only the oscillating body shaft 10 shows a cross section cut at the interval securing member 19 n. Fig. 10 is an enlarged view showing the periphery of the interval securing member according to the fourth embodiment.

The flex-meshing gear device 1C according to the fourth embodiment is different from the third embodiment mainly in the distance securing members 19n to 19q, and other constituent elements are the same as those of the third embodiment. Therefore, the same components are denoted by the same reference numerals, and detailed description thereof will be omitted.

The interval securing members 19n to 19q are made of, for example, elastic members such as rubber, resin, and springs (leaf springs). When rubber, resin, or the like is used, the young 'S modulus of the space ensuring members 19n to 19q is lower than the young' S modulus of the rolling surface S1 on which the roller 15Aa rolls. When the space ensuring members 19n to 19q are made of leaf springs, the young 'S modulus of the space ensuring members 19n to 19q may be equal to or higher than the young' S modulus of the rolling surface S1.

The interval securing members 19n to 19q are attached to the oscillating body 10A and rotate together with the oscillating body 10A. The gap securing members 19n to 19q are bonded and fixed to grooves 10mn to 10mq (see fig. 10) provided in the oscillating body 10A, for example. The grooves 10mn to 10mq have an annular shape along the outer periphery of the oscillating body 10A and are provided at positions near both end portions of the roller 15Aa in the axial direction.

The interval securing members 19n to 19q each include a base portion B at least a part of which is accommodated in the grooves 10mn to 10mq, and a protruding portion T protruding outside the grooves 10mn to 10 mq. As shown in fig. 9, the base B has a shape of a ring connected. A part of the base B may protrude outward from the outer peripheral surface of the oscillating body 10A within a range not in contact with the roller 15 Aa. The protruding portion T is arranged at a plurality of locations (for example, four locations) between the range W1 and the range W2 in the circumferential direction of the oscillating body shaft 10. More specifically, the protruding portion T is disposed at a plurality of locations (for example, four locations) including both end sections in the circumferential direction of the range W2.

As shown in fig. 10, the protruding portion T is axially opposed to both end portions (end faces in the axial direction) of the roller 15Aa passing therethrough, and is in contact with both end portions of the roller 15 Aa. In other words, the distance L1 between the contact portion of the protrusion T capable of contacting one end surface in the axial direction of the roller 15Aa and the contact portion of the protrusion T capable of contacting the other end surface in the pair of protrusions T opposing the one roller 15Aa is shorter than the length L2 in the axial direction of the roller 15 Aa. The distance L1 is a distance between the protruding portions T (indicated by two-dot chain lines in fig. 10) in the case where the roller 15Aa does not enter between the protruding portions T.

In fig. 8 and 9, the spacer rings 36a, 36b, 37a, 37b (refer to fig. 1) that suppress the plurality of rollers 15Aa from moving in the axial direction are omitted. However, the spacer rings 36a, 36b, 37a, 37b may be circumferentially divided into a plurality of sections or provided with notches so as to avoid the protruding portion T, and may be disposed on both sides in the axial direction of the roller 15Aa within a range not overlapping the protruding portion T.

With the above-described configuration, each of the protruding portions T of the interval securing members 19n to 19q contacts the roller 15Aa moving from the range W2 (refer to fig. 9) to the range W1, and applies a braking force to the roller 15Aa, thereby securing an interval between the roller 15Aa entering the range W1 and the preceding roller 15 Aa. When braking force is applied, the protruding portions of the interval securing members 19n to 19q are in contact with both end surfaces of the roller 15Aa in the axial direction, and therefore, the roller 15Aa can be prevented from being skewed.

As described above, according to the flexible meshing gear device 1C of the fourth embodiment, the skew of the rollers 15Aa can be suppressed and the intervals between the plurality of rollers 15Aa can be ensured in the range W1. Therefore, the fatigue life of the oscillating body bearing 15 can be prolonged.

Further, according to the flexible meshing gear device 1C of the fourth embodiment, the space ensuring members 19n to 19q are arranged to be in contact with both end surfaces in the axial direction of the roller 15 Aa. Therefore, when the gap ensuring members 19n to 19q contact the roller 15Aa, the roller 15Aa can be stably prevented from being skewed. Further, since the interval securing members 19n to 19q have a shape continuous in the circumferential direction, the number of parts is reduced as compared with the configuration of the first embodiment, and the number of assembly steps of the interval securing members 19n to 19q can be reduced.

The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments. For example, the first to third embodiments show the interval securing members 19a to 19h having a young' S modulus lower than that of the rolling surface S1, and the fourth embodiment shows the interval securing members 19n to 19q having elasticity. However, the present invention is not limited to this, and any interval securing member may be used as long as it applies a braking force to the revolution movement of the 1 st roller in the direction of the 2 nd roller to secure the interval between the 1 st roller and the 2 nd roller, and for example, an interval securing member described in international publication No. 2018/025296 may be used. For example, leaf springs, and the like may be used for the interval securing members 19a to 19h of the first to third embodiments. The interval securing members 19a to 19h, 19n to 19q of the first to fourth embodiments may be constituted by magnets, and may apply braking force to the magnetic rollers 15A, 15Aa based on magnetic force. In this case, when the arrangement of the first to third embodiments is adopted, the interval securing members may be provided so as to be recessed inward of the rolling surface S1 or so that the outer surfaces thereof are flush with the rolling surface S1 so as not to interfere with the rolling of the

rollers

15A, 15 Aa. Alternatively, when the arrangement of the fourth embodiment is adopted, the interval securing member constituted by the magnet may be provided with a play between it and the roller 15Aa so as not to interfere with the rolling of the roller 15 Aa. In the drawings of the above embodiments, the portions of the interval securing members 19a to 19h, 19n to 19q that contact the rollers 15A, 15Aa are formed in a flat shape, but claw portions protruding at acute angles may be provided at the contact portions. The distance securing member according to the present invention may be configured such that the width of the fixing portion fixed to the oscillating body 10A and supporting the contact portion is smaller than the width of the portion in contact with the rollers 15A, 15Aa, so that the portion in contact with the rollers 15A, 15Aa swings in the traveling direction of the

rollers

15A, 15 Aa.

In the first to fourth embodiments, the cross-sectional shape of the oscillating body 10A is elliptical, and the external gear 12 is deflected into an elliptical shape. However, the shape of the vibrator 10A is not limited to this, and for example, a three-lobe (lobe) shape may be employed in which a gentle curvature is added to the corners and sides of a regular triangle in cross-sectional shape. At this time, the rollers are clamped in a tight state at the portions corresponding to the corners of the regular triangle, and therefore, the space securing members need only be provided at six positions in the circumferential direction.

While the above-described first to fourth embodiments have shown the configuration in which the distance securing member is attached to the vibration starting body 10A, the distance securing member may be attached to another portion and rotated integrally with the vibration starting body 10A. For example, when the oscillating body bearing has an inner ring, the interval securing member may be attached to the inner ring.

In the first to fourth embodiments, the rollers of the oscillating body bearing are arranged in two rows in the axial direction, but the rollers may be arranged in one row. The end surfaces of the roller in the axial direction may be planar end surfaces or curved end surfaces as in the embodiment.

In the first to fourth embodiments, the present invention is applied to a so-called cylindrical flex-meshing gear device, but the present invention is not limited to this, and the present invention can be similarly applied to a so-called cup-type flex-meshing gear device or a top hat-type flex-meshing gear device. In addition, the details shown in the embodiments can be changed appropriately without departing from the gist of the present invention.

Claims

1. A flexible meshing gear device is provided with: an internal gear; an external gear engaged with the internal gear; a vibration starting body for deforming the external gear; and a vibration starting body bearing disposed between the vibration starting body and the external gear, wherein the flexible meshing gear device is characterized by further comprising a gap ensuring member integrally rotating with the vibration starting body, the vibration starting body comprises a plurality of rollers, the plurality of rollers comprise rollers which are clamped between a 1 st rolling surface on the inner circumference side and a 2 nd rolling surface on the outer circumference side in a loose state and rollers which are clamped between the 1 st rolling surface on the inner circumference side and the 2 nd rolling surface on the outer circumference side in a tight state, when the rollers in the loose state and the rollers in the tight state which are adjacent to each other in the plurality of rollers are respectively referred to as the 1 st roller and the 2 nd roller, the gap ensuring member is a member which applies braking force to the revolution motion of the 1 st roller in the direction of the 2 nd roller so as to ensure a gap between the 1 st roller and the 2 nd roller, and the gap ensuring member is disposed intermittently along the circumferential direction of the vibration starting body between the rollers and the two ends of the rollers in the axial direction, and the gap ensuring member is disposed intermittently along the rolling surface of the vibration starting body, and the gap ensuring member is disposed in a range of the gap between the 1 st rolling surface and the roller in the contact position W which is disposed between the roll surface W and the gap ensuring member is disposed intermittently along the circumferential surface W in the contact between the gap between the two opposite surfaces between the two rollers in the roll surface 1 and the roll surface in the contact position between the roll surface.

2. The flexible meshing gear device according to claim 1, wherein the young's modulus of the space ensuring member is smaller than the young's modulus of the 1 st rolling surface.

3. The flexible meshing gear device according to claim 2, wherein the space ensuring member protrudes further toward a space side in which the roller rolls than the 1 st rolling surface.

4. A flexspline gear according to claim 3, wherein both ends of the plurality of rollers in the axial direction have convex surface portions that are not in contact with the 1 st rolling surface but in contact with the space ensuring member.

5. The flexible meshing gear device according to claim 1, wherein the space ensuring member is opposed to an entire area in an axial direction of the roller.

6. A flexible meshing gear device is provided with: an internal gear; an external gear engaged with the internal gear; a vibration starting body for deforming the external gear; and a vibration starting body bearing disposed between the vibration starting body and the external gear, wherein the vibration starting body is further provided with a gap ensuring member integrally rotating with the vibration starting body, the vibration starting body is provided with a plurality of rollers, the plurality of rollers include rollers which are clamped between a 1 st rolling surface on the inner circumference side and a 2 nd rolling surface on the outer circumference side in a loose state and rollers which are clamped between the 1 st rolling surface on the inner circumference side and the 2 nd rolling surface on the outer circumference side in a tight state, when the rollers in the loose state and the rollers in the tight state which are adjacent to each other in the plurality of rollers are respectively referred to as the 1 st roller and the 2 nd roller, the gap ensuring member is a member which applies braking force to the revolution motion of the 1 st roller in the direction of the 2 nd roller so as to ensure a gap between the 1 st roller and the 2 nd roller, and the gap ensuring member is disposed along the circumferential direction opposite to the roller, the gap ensuring member is disposed along the gap between the 1 st rolling surface and the 2 nd roller in the loose state and the gap ensuring member is disposed along the circumferential direction opposite to the circumferential surface of the roller, and the gap ensuring member is disposed along the gap between the roll surface W1 and the gap ensuring member is disposed along the gap between the circumferential surface and the gap between the roll surface W and the roll surface and the circumferential surface.