JP2020003017A - Wave speed reduction device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wave speed reducer capable of facilitating assembly by allowing a tilt at the time of assembly. A wave reduction gear transmission (1) is connected to an input shaft (10) extending in an axis (X1) direction, an output shaft (20) extending in an axis (X1) direction, a rotary pressing member (30) connected to the input shaft (10), and an output shaft (20). A flexible gear 50 having flexibility, a fixed gear 60 that faces the flexible gear 50 in the direction of the axis X1 and cannot rotate around the axis X1, and a pressing surface that faces the output side in the direction of the axis X1. The output-direction surface 70a as a surface is provided, and the rotation pressing member 30 is rotatable on the output-direction surface 70a and is movable in an annular shape around the axis X1. [Selection diagram] Fig. 4

Description

  The present invention relates to a wave reduction gear.

  2. Description of the Related Art Conventionally, a wave reduction gear has been used for a reduction gear that is small and requires a high reduction ratio. A conventional wave reduction device includes, for example, an elliptical disk-shaped rotating mechanism called a wave generator mounted on an input shaft, a flexible gear mounted on an output shaft, a rolling bearing, and a fixed gear. The fixed gear is formed on the cylindrical surface toward the inner peripheral side, and the flexible gear is pushed from the inner peripheral side by a wave generator rotating through a rolling bearing, and is partially attached to the fixed gear from the inner peripheral side. It is designed to mesh with each other. The fixed gear and the flexible gear have different numbers of teeth, and the difference in the number of teeth causes the rotation of the input shaft to be reduced and transmitted to the output shaft via the flexible gear (for example, See Patent Document 1.).

U.S. Pat. No. 2,906,143

  In the wave reduction gear, the meshing of the gears needs to be appropriately adjusted in order to transmit the power appropriately. For this reason, the wave generator is arranged parallel to the flexible gear without inclination, and it is necessary to press the flexible gear in parallel. However, in the conventional wave speed reducer, it is difficult to arrange the wave generator and the flexible gears in parallel without tilting during assembly, and the flexible gears are not pressed in parallel by the wave generator, so that the entirety of the gears is not provided. The meshing is not constant over the circumference, and there is a possibility that the operation of the gear may be stopped or the gear may be damaged. As described above, there has been a demand for a conventional wave speed reducer having a structure capable of allowing an inclination during assembly and facilitating assembly.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a wave reduction gear capable of allowing an inclination during assembly and facilitating assembly.

  In order to achieve the above object, a wave reduction gear transmission according to the present invention includes an input shaft extending in an axial direction, an output shaft extending in the axial direction, a rotation pressing member connected to the input shaft, and an output shaft. A connected flexible gear, a fixed gear that faces the flexible gear in the axial direction and that cannot rotate around the axis, and a surface facing the output side in the axial direction. A pressing surface, wherein the rotary pressing member is rotatable on the pressing surface and is annularly movable around the axis.

  The flexible gear has a tooth forming surface that is a surface facing the output side in the axial direction, a pressed surface that is a surface facing the tooth forming surface, and an annular shape around the axis on the tooth forming surface. The fixed gear has a tooth forming surface facing the input side in the axial direction, and the flexible gear has a ring shape around the axis on the tooth forming surface. A plurality of teeth arranged opposite to the teeth, wherein the number of teeth of the flexible gear is different from the number of teeth of the fixed gear; Has at least one pressing member that abuts against the pressed surface from the input side and engages a part of the teeth of the flexible gear with a part of the teeth of the fixed gear. The rotation pressing member is provided on the input side of the pressing member in the axial direction, and Member, the pressing member and is provided at different positions around the axis, the pressing member is movable annularly around said rotating the upper pressing surface axis and at least one has.

  In the wave reduction gear according to one aspect of the present invention, the pressing member is provided at a position different from the pressing member by 90 degrees in a rotation direction of the axis.

  The wave reduction gear according to one aspect of the present invention includes the two pressing members, and the pressing members are arranged to face each other across the axis.

  The wave speed reducer according to one aspect of the present invention includes the two pressing members, and the pressing members are arranged to face each other with the axis interposed therebetween.

  In the wave reduction gear according to one aspect of the present invention, the output shaft is rotatably supported by the fixed gear via a bearing, and the flexible gear biases the output shaft and the bearing. are doing.

  ADVANTAGE OF THE INVENTION According to the wave speed reducer which concerns on this invention, the inclination at the time of an assembly is permitted, and an assembly can be facilitated.

It is a perspective view showing roughly appearance composition of a wave reduction gear concerning an embodiment of the invention. It is a perspective view showing roughly the composition of the wave reduction gear which shows the wave reduction gear concerning the embodiment of the invention except for a case. FIG. 2 is an exploded perspective view schematically showing a configuration of the wave reduction gear, showing the wave reduction gear according to the embodiment of the present invention without a case. It is a sectional perspective view showing roughly composition of a wave reduction gear concerning an embodiment of the invention. It is AA sectional drawing in FIG. It is an expanded sectional view in FIG. It is BB sectional drawing in FIG. It is an expanded sectional view in FIG. It is a perspective view showing roughly composition of a rotation pressing member of a wave reduction gear concerning an embodiment of the invention. It is a side view which shows roughly the structure of the rotation pressing member of the wave reduction gear which concerns on embodiment of this invention. It is a perspective view showing roughly composition of a flexible gear of a wave reduction gear concerning an embodiment of the invention. It is an exploded perspective view showing roughly composition of a flexible gear of a wave reduction gear concerning an embodiment of the invention. It is the disassembled perspective view seen from another direction which shows roughly the structure of the flexible gear of the wave reduction gear which concerns on embodiment of this invention. It is a perspective view showing roughly composition of a fixed gear of a wave reduction gear concerning an embodiment of the invention. It is an expanded sectional view showing typically composition of a wave reduction gear concerning an embodiment of the present invention when an output direction surface of a contact part is not parallel to an input direction surface of a fixed gear. FIG. 16 is an enlarged cross-sectional view schematically illustrating the wave reduction device according to the embodiment of the present invention in a state where the rotation pressing member has rotated 90 degrees around an axis that is the center axis of the input shaft from the state illustrated in FIG. 15.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view schematically showing an external configuration of a wave speed reducer 1 according to an embodiment of the present invention. FIG. 2 is a wave speed reducer showing the wave speed reducer 1 without a case 2. 1 is a perspective view schematically showing a configuration of FIG. FIG. 3 is an exploded perspective view schematically showing the configuration of the wave reduction gear 1 showing the wave reduction gear 1 without the case 2, and FIG. 4 is a schematic view showing the configuration of the wave reduction gear 1. It is a sectional perspective view. FIG. 5 is an AA cross-sectional view in FIG. 1, and FIG. 6 is an enlarged cross-sectional view in FIG. FIG. 7 is a sectional view taken along the line BB in FIG. 1, and FIG. 8 is an enlarged sectional view in FIG. As shown in FIGS. 1 to 8, the wave reduction gear 1 according to the embodiment of the present invention includes an input shaft 10 extending in the direction of the central axis X <b> 1 of the wave reduction gear 1, an output shaft 20 extending in the direction of the axis X <b> 1, The rotation pressing member 30 connected to the shaft 10, the flexible gear 50 connected to the output shaft 20, and the flexible gear 50 facing the flexible gear 50 in the direction of the axis X1, and cannot rotate around the axis X1. A fixed gear 60, and an output direction surface 70a as a pressing surface that faces the output side in the direction of the axis X1. The rotation pressing member 30 rotates on the output direction surface 70a to form a ring around the axis X1. It is possible to move to.

  The flexible gear 50 has an output direction surface 51a (see FIG. 9 described later) as a tooth forming surface which is a surface facing the output side in the direction of the axis X1, and a pressed surface which is a surface facing the output direction surface 51a. It has an input direction surface 51b as a surface and a plurality of teeth 52 arranged annularly around the axis X1 on the output direction surface 51a. The fixed gear 60 is arranged opposite to the teeth 52 of the flexible gear 50 in an annular shape around the axis X1 on the input direction surface 61b as a tooth forming surface facing the input side in the direction of the axis X1. And a plurality of teeth 62. The number of teeth 52 of the flexible gear 50 is different from the number of teeth 62 of the fixed gear 60. The rotation pressing member 30 is in contact with the input direction surface 51 b of the flexible gear 50 from the input side to engage a part of the teeth 52 of the flexible gear 50 with a part of the teeth 62 of the fixed gear 60. At least one. The output direction surface 70a is provided on the input side of the pressing member 31 of the rotary pressing member 30 in the direction of the axis X1. The rotation pressing member 30 is provided at a position different from the pressing member 31 around the axis X1, and has at least one pressing member 45 that can rotate on the output direction surface 70a and move annularly around the axis X1. ing. 5 and 6 indicate the plurality of teeth 52 arranged on the output direction surface 51a of the flexible gear base 51 and the plurality of teeth 62 arranged on the input direction surface 61b of the fixed gear base 61. Are shown. Hereinafter, the configuration of the wave reduction device 1 will be specifically described.

  FIG. 9 is a perspective view schematically illustrating a configuration of the rotation pressing member 30 of the wave reduction gear 1 according to the embodiment of the present invention, and FIG. 10 is a schematic diagram illustrating a configuration of the rotation pressing member 30 of the wave reduction gear 1. FIG. As shown in FIGS. 1 to 10, in the wave reduction device 1, the rotation pressing member 30 is formed in, for example, a square plate shape or a substantially square plate shape whose four corners are chamfered, and is formed of, for example, metal. I have. In the rotation pressing member 30, the input shaft 10 is provided upright from the center of the input direction surface 30b on the input direction surface 30b which is a surface facing the input side in the direction of the axis X4 which is the center axis of the input shaft 10. The input shaft 10 is formed in an elongated cylindrical rod shape or a substantially cylindrical rod shape extending along the direction of the axis X4, and is formed of, for example, metal. The input shaft 10 is formed integrally with the rotation pressing member 30. The input shaft 10 and the rotation pressing member 30 are disposed coaxially, and have the axis X4 as the central axis. The input shaft 10 is rotatably supported by a bearing 11 such as a shield bearing. An outer peripheral surface 11a of the bearing 11 is fixed to a case 2 described later.

  In the present embodiment, the rotation pressing member 30 has two pressing members 31, and the pressing members 31 are arranged to face each other across the axis X4. Specifically, the rotation pressing member 30 has a pair of parallel rectangular or substantially rectangular flat surfaces 32, 33 extending in parallel with the direction of the axis X4. On the pair of flat surfaces 32, 33, a pair of columnar or substantially columnar bearing support portions 34, 35 centered or substantially centered on an axis X2 orthogonal to the pair of flat surfaces 32, 33, respectively, are provided upright. I have. The pair of bearing support portions 34, 35 are provided with a pair of ball bearings 36, 37, respectively, as the above-described pressing member 31. Inner peripheral surfaces 36a, 37a of the pair of ball bearings 36, 37 are fixed to outer peripheral surfaces 34a, 35a of the pair of bearing support portions 34, 35, respectively. The pair of ball bearings 36 and 37 are disposed coaxially, and have the axis X2 as the central axis. The outer peripheral surfaces 36b, 37b of the pair of ball bearings 36, 37 can contact the input direction surface 51b as the pressed surface of the flexible gear 50.

  In the rotation pressing member 30, the pressing member 45 is provided at a position different from the pressing member 31 by 90 degrees in the rotation direction of the axis X <b> 4. In the present embodiment, the rotation pressing member 30 has two pressing members 45, and the pressing members 45 are arranged to face each other across the axis X4. Specifically, the rotation pressing member 30 has a pair of parallel rectangular or substantially rectangular flat surfaces 38 and 39 extending in parallel with the direction of the axis X4. The pair of flat surfaces 38, 39 have a columnar or substantially columnar shape centered or substantially centered on an axis X3 orthogonal to the pair of flat surfaces 38, 39 at a position shifted from the axis X2 by a distance L toward the input side. A pair of bearing support portions 40 and 41 are provided upright. Note that the axis X3 may also extend perpendicular to the axis X2. A pair of ball bearings 42, 43 are provided on the pair of bearing support portions 40, 41, respectively. Inner peripheral surfaces 42a, 43a of the pair of ball bearings 42, 43 are fixed to outer peripheral surfaces 40a, 41a of the pair of bearing support portions 40, 41, respectively. The pair of ball bearings 42 and 43 are arranged coaxially, and have the axis X3 as the central axis. The outer peripheral surfaces 42b and 43b of the pair of ball bearings 42 and 43 are rotatably in contact with the output direction surface 70a. In addition, the output shaft 20 which spreads in a disk shape around the center or substantially the center of the output direction surface 30a and the flexible shaft to be described later are provided on the output direction surface 30a which is the surface where the rotation pressing member 30 faces the output side in the direction of the axis X4. An escape space 44 for the plate portion 53 of the gear base 51 is formed.

  FIG. 11 is a perspective view schematically showing a configuration of a flexible gear 50 of the wave reduction gear transmission 1 according to the embodiment of the present invention. FIG. 12 is an exploded perspective view schematically showing the configuration of a flexible gear 50 of the wave reduction gear 1, and FIG. 13 is another exploded view schematically showing the configuration of the flexible gear 50 of the wave reduction gear 1. It is the disassembled perspective view seen from the direction. As shown in FIGS. 1 to 8 and 11 to 13, in the wave reduction gear 1, the flexible gear 50 has a disk-shaped or substantially disk-shaped flexible gear base 51. The flexible gear base 51 is formed of a metal or the like having a thickness capable of bending in the direction of the axis X1. The flexible gear base 51 is formed of, for example, a leaf spring material. At the center or substantially the center of the flexible gear base 51, there are an input direction surface 51b as a pressed surface, which is a surface facing the input side in the direction of the axis X1 of the flexible gear base 51, and a surface facing the output side. A through hole 51c penetrating the flexible gear base 51 is formed between the output gear surface 51a and a certain tooth forming surface. The output shaft 20 is inserted into the through hole 51c of the flexible gear base 51. The output shaft 20 is formed in an elongated cylindrical rod shape or a substantially cylindrical rod shape extending along the direction of the axis X1, and is formed of, for example, metal. The diameter of the output shaft 20 is the same or substantially the same as the diameter of the through hole 51 c of the flexible gear base 51, and is larger than the diameter of the input shaft 10. The output shaft 20 may be formed integrally with the flexible gear base 51.

  An annular or substantially annular flange portion 21 a having a diameter larger than the diameter of the output shaft 20 is provided on the outer peripheral surface of the output shaft 20 near the input side end of the output shaft 20. The flexible gear 50 has an annular or substantially annular plate portion 53, and the plate portion 53 has the same or substantially the same size as the flange portion 21. The plate portion 53 has a through hole penetrating the plate portion 53 between an output direction surface 53a which is a surface facing the output side in the direction of the axis X1 of the plate portion 53 and an input direction surface 53b which is a surface facing the input side. A hole 53c is formed. The diameter of the through hole 53c of the plate portion 53 is the same or substantially the same as the diameter of the through hole 51c of the flexible gear base 51 and the output shaft 20. The input end 20a of the output shaft 20 is inserted into the through hole 53c of the plate portion 53.

  A plurality of screw holes 22 are formed in the flange portion 21a, and a through hole 51d and a through hole 54 are formed in the flexible gear base 51 and the plate portion 53 at positions corresponding to the screw holes 22, respectively. The flexible gear base 51 is sandwiched between the flange portion 21 a and the plate portion 53, and the bolt 55 inserted into the through holes 51 d and 54 is screwed into the screw hole 22, so that the flange portion 21 and the plate portion 53 and is fixed. The output shaft 20, the flexible gear base 51, and the plate portion 53 are coaxially arranged, and have the axis X1 as a central axis.

  In the vicinity of the end on the input side of the output shaft 20, an outer peripheral surface of the output shaft 20 is formed integrally with and adjacent to a surface of the flange 21 a facing the output side in the direction of the axis X <b> 1. Is provided with an annular or substantially annular flange portion 21b smaller than the diameter of the flange 21b. The output direction surface 21c of the flange portion 21b is in contact with an input direction surface 23b of an inner ring of the bearing 23 described later, and positions the output shaft 20 in the direction of the axis X1. The output shaft 20 is rotatably supported by bearings 23 and 24 such as ball bearings and shield bearings. The outer peripheral surfaces 23a and 24a of the bearings 23 and 24 are fixed to a fixed gear 60 described later.

  The flexible gear base 51 formed of a leaf spring material or the like has a plurality of teeth 52 arranged on the output direction surface 51a of the flexible gear base 51 and a plurality of teeth 52 arranged on the input direction surface 61b of the fixed gear base 61. In order to partially mesh with the tooth 62 of the rotary pressing member 30, the rotary pressing member 30 is bent in the direction of the axis X1 by a pair of ball bearings 36 and 37 which are the pressing portions 31 disposed on the rotary pressing member 30. That is, the flexible gear 50 is always urged in the output direction in the direction of the axis X1. At this time, since the flange portions 21a and 21b, the plate portion 53, and the output shaft 20 which are connected to the flexible gear base 51 integrally form the flexible gear 50, the output shaft 20 and the flange portion are formed. An urging force is also applied to 21b in the output direction in the direction of the axis X1. Further, the output direction surface 21c of the flange portion 21b is in contact with the input direction surface 23b of the inner ring of the bearing 23, and the outer peripheral surface 23a of the bearing 23 is engaged with the through hole 63a of the flange portion 63 of the fixed gear base 61. Therefore, an urging force is applied to the outer race of the bearing 23 from the inner race in the output direction in the direction of the axis X1. That is, a so-called preload is applied to the bearing 23, so that the inner ring has no backlash with respect to the outer ring and is accurately coaxial. Further, the position of the output shaft 20 in the direction of the axis X1 can be defined. As described above, the flexible gear base 51 formed of a leaf spring material or the like also has a role as a preload urging spring for the bearing 23.

  The plurality of teeth 52 on the output direction surface 51a of the flexible gear base 51 are flat teeth having a predetermined length from the outer edge of the flexible gear base 51 extending in the radial direction toward the inner peripheral side. The portion meshes with a plurality of teeth 62 of a fixed gear 60 described later. The number of teeth 52 of the flexible gear base 51 is, for example, 200 teeth.

  FIG. 14 is a perspective view schematically showing the configuration of fixed gear 60 of wave reduction gear 1 according to the embodiment of the present invention. As shown in FIGS. 1 to 8 and 14, in the wave reduction gear transmission 1, the fixed gear 60 has a disc-shaped or substantially disc-shaped fixed gear base 61 centered or substantially centered on the axis X <b> 1. The fixed gear base 61 has a predetermined thickness in the direction of the axis X1, for example, and is formed of metal or the like. At the center or substantially the center of the fixed gear base 61, an input direction surface 61b as a tooth forming surface which is a surface facing the input side in the direction of the axis X1 of the fixed gear base 61 and an output direction surface which is a surface facing the output side. A through-hole 61c penetrating through the fixed gear base 61 is formed between the through-hole 61c and the base 61a. At the end on the inner peripheral side of the output direction surface 61a of the fixed gear base 61, a cylindrical or substantially cylindrical flange portion 63 centered or substantially centered on the axis X1 extending toward the output side is provided. The output shaft 20 is inserted through the through hole 61c of the fixed gear base 61 and the through hole 63a of the flange portion 63. The outer peripheral surfaces 23a, 24a of the bearings 23, 24 are locked in through holes 63a of the flange portion 63.

  The plurality of teeth 62 of the input direction surface 61b of the fixed gear base 61 are the same or substantially the same as the plurality of teeth 52 of the flexible gear base 51 at positions facing the plurality of teeth 52 of the flexible gear base 51, respectively. It is a flat tooth having a length, and a part thereof meshes with a plurality of teeth 52 of the flexible gear 50. The number of the teeth 62 of the fixed gear base 61 is larger than the number of the teeth 52 of the flexible gear 50, for example, 202 teeth, which is two teeth more than the number of the teeth 52 of the flexible gear 50. More. Note that the relationship between the number of teeth 62 of the fixed gear base 61 and the number of teeth 52 of the flexible gear 50 is not limited to the above, and the number of teeth 62 of the fixed gear base 61 is May be less than the number of the teeth 52 of the first embodiment. In this case, when the output shaft 20 rotates the input shaft 10 when the number of teeth 62 of the fixed gear base 61 is larger than the number of teeth 52 of the flexible gear 50, Will rotate in the opposite direction.

  As shown in FIGS. 1 to 8, in the wave reduction gear 1, the case 2 supports the input shaft 10 and accommodates the rotation pressing member 30, the flexible gear 50, and the fixed gear 60 therein. Specifically, the case 2 is a cylindrical member having a bottom or a substantially cylindrical member having a bottom, and has a predetermined depth formed so as to accommodate the rotation pressing member 30, the flexible gear 50, and the fixed gear 60. The accommodation concave part 3 which is a concave part which has this is formed. The case 2 is formed of, for example, metal. The case 2 includes a disk-shaped or substantially disk-shaped disk portion 4, and a cylindrical or substantially cylindrical cylindrical portion 5 erected from an output direction surface 4 a on the output side of the disk portion 4. The cylindrical portion 5 is formed, for example, on the outer edge of the disk portion 4. The arrangement position of the cylindrical portion 5 in the case 2 is not limited to this, and the cylindrical portion 5 may be formed inside the outer edge of the disk portion 4 in the case 2. The cylindrical portion 5 is formed integrally with the disk portion 4. The disk portion 4 and the cylindrical portion 5 are arranged coaxially, and have the axis X1 as the central axis.

  At the center or substantially the center of the disk portion 4, a disk portion is formed between an output direction surface 4a which is a surface facing the output side in the direction of the axis X1 of the disk portion 4 and an input direction surface 4b which is a surface facing the input side. 4, a through hole 4c is formed. A cylindrical or substantially cylindrical flange portion 6 centered or substantially centered on an axis X1 extending toward the output side is provided at an end on the inner peripheral side of the output direction surface 4a of the disk portion 4. The input shaft 10 is inserted through the through hole 4 c and the flange 6 of the disk 4. The diameter of the through hole 4c of the disk part 4 and the inner peripheral surface of the flange part 6 are larger than the diameter of the input shaft 10. The disk portion 4 and the flange portion 6 are arranged coaxially, and have the axis X1 as the central axis. An outer peripheral surface 11 a of the bearing 11 is fixed to an inner peripheral surface of the flange portion 6.

  Moreover, the wave reduction gear 1 further includes an output direction surface 70a as a pressing surface which is a surface facing the output side. The output direction surface 70a is provided on the input side of the pressing member 31 of the rotary pressing member 30 in the direction of the axis X1. Specifically, in the case 2, a contact portion 70 that contacts the rotation pressing member 30 in the direction of the axis X <b> 1 is provided. Are provided opposite to each other. The contact portion 70 is formed in a disk shape or a substantially disk shape, and has a shape that is the same or substantially the same as that of the housing recess 3 in a cross section orthogonal to the axis X1. The contact portion 70 includes a contact portion 70 between an output direction surface 70a as a pressing surface which is a surface facing the output side in the direction of the axis X1 of the contact portion 70 and an input direction surface 70b which is a surface facing the input side. , A through hole 70c centered or substantially centered on the axis X1 is formed. The flange portion 6 is inserted into the through hole 70c of the contact portion 70. The output direction surface 70a is a plane or a substantially plane perpendicular or substantially perpendicular to the axis X1. The diameter of the through hole 70 c of the contact portion 70 is the same or substantially the same as the outer peripheral surface of the flange portion 6. The contact portion 70 is in contact with the outer peripheral surfaces 42b, 43b of the pair of ball bearings 42, 43 as the pressing member 45 of the rotary pressing member 30 on the output direction surface 70a. Note that the contact portion 70 in the case 2 is not limited to the case where the contact portion is separate, and the contact portion 70 may be integrated with the case 2. In this case, the output direction surface 4a of the disk part 4 functions as a pressing surface. The contact portion 70 may be movable (position adjustable) in the direction of the axis X1 in the case 2.

  Subsequently, an operation of the wave reduction gear 1 having the above-described configuration will be described. In the wave reduction gear 1, when the input shaft 10 is driven to rotate around the axis X4, the rotation pressing member 30 rotates around the axis X4. When the rotation pressing member 30 rotates, the pair of ball bearings 36 and 37 rotate (rotate) on the input direction surface 51b of the flexible gear 50 to move (revolve) in an annular shape around the axis X1, and to rotate the pair of balls. The bearings 42 and 43 rotate (rotate) on the output direction surface 70a of the contact portion 70 and move (revolve) in an annular shape around the axis X1. When the pair of ball bearings 36 and 37 move annularly around the axis X1 and press the pair of ball bearings 36 and 37 on the input direction surface 51b of the flexible gear 50, the flexibility of the flexible gear 50 is increased. The gear base 51 is bent toward the output side, and a part of the teeth 52 of the flexible gear 50 meshes with a part of the teeth 62 of the fixed gear 60. The number of teeth 62 of the fixed gear 60 is 202, and the number of teeth 52 of the flexible gear 50 is 200, which is two less than the number of teeth 62 of the fixed gear 60. In the wave reduction device 1, the rotation of the input shaft 10 is controlled by the difference between the number of the teeth 52 of the flexible gear 50 and the number of the teeth 62 of the fixed gear 60 according to the same principle as the known wave gear device. The speed can be reduced and transmitted to the output shaft 20 via the flexible gear 50, the flexible gear 50 and the fixed gear 60.

  In the wave speed reducer 1 according to the embodiment of the present invention, the rotation pressing member 30 has the pressing member 31 and the plurality of pressing members 45 at different positions around the axis X1. It rotates on 70a and moves annularly around the axis X1.

  FIG. 15 is a cross-sectional view of the wave reduction device 1 taken along the line AA in FIG. 1 (FIG. 5). The contact portion 70 is not uniform in thickness due to manufacturing accuracy or the like. FIG. 2 is an enlarged cross-sectional view schematically illustrating a configuration of a wave reduction device 1 according to an embodiment of the present invention, in a case where is not parallel to an input direction surface 61b of a fixed gear 60. FIG. 16 is an enlarged cross-sectional view schematically showing the wave reduction device 1 according to the embodiment of the present invention in a state where the rotation pressing member 30 has been rotated by 90 degrees around the central axis X4 from the state shown in FIG. . In the wave reduction gear 1 according to the embodiment of the present invention, even if the output direction surface 70a of the contact portion 70 is not parallel to the input direction surface 61b of the fixed gear 60 as shown in FIGS. Since the axis X2 and the axis X3, which are the central axes of the pressing member 31 and the pressing member 45, are respectively orthogonal to the axis X4, and the axis X2 and the axis X3 are arranged at positions orthogonal to each other when viewed from the axis X4 direction. The distance L between the center of the center line X3 connecting the centers of the bearings 42 and 43 and the center of the center line X2 connecting the centers of the bearings 36 and 37 does not always change. That is, the output direction surface 70a of the contact portion 70 is fixed to the fixed gear 60. The input shaft 10 rotates while swinging even if the input shaft 10 is tilted with respect to the input direction surface 61b. Thereby, while the pressing member 31 keeps contact with the input direction surface 51b of the flexible gear 50 and the pressing member 45 keeps contacting with the output direction surface 70a of the contact portion 70, the rotation pressing member 30 rotates. I do.

  At this time, the distance between the axis X3, which is the central axis of the pressing member 45, and the output direction surface 70a of the contact portion 70 is the radius of the ball bearings 42, 43, and is always constant. The distance between the contact portion 70 and the output direction surface 70a is the radius of the ball bearings 42 and 43 and is always constant. Similarly, the distance between the axis X2, which is the central axis of the pressing member 31, and the input direction surface 61b of the fixed gear 60 is the radius of the ball bearings 36, 37, and is always constant, and the distance between the axis X2 and the axis X4 is constant. The distance between the intersection and the input direction surface 61b of the fixed gear 60 is the radius of the ball bearings 36 and 37, and is always constant. The distance L between the axis X2 and the axis X3 (FIGS. 15 and 16) is always constant. That is, the distance between the output direction surface 70a of the contact portion 70 and the input direction surface 61b of the fixed gear 60, which determines the pressing force of the flexible gear 50 by the pressing member 31, is constant. The pressing force on the gear 50 becomes constant.

  Therefore, even if the output direction surface 70a is inclined with respect to the axis X1 and the input direction surface 61b and the output direction surface 70a of the fixed gear 60 are not arranged in parallel, the output direction surface 70a is pressed against the inclination of the output direction surface 70a. The distance between the input direction surface 61b and the output direction surface 70a of the fixed gear 60 can be kept constant by the member 45 following. For this reason, the pressing member 31 can press the input direction surface 51b of the flexible gear 50 over the entire circumference with a constant pressing force, so that a part of the teeth 52 of the flexible gear 50 and the fixed gear The amount of engagement of the 60 teeth with a part of the teeth 62 can be constant over the entire circumference. As a result, unlike the related art, the engagement amount does not become constant over the entire circumference of the gear, and it is possible to prevent the operation of the gear from being stopped or the gear from being damaged. As described above, in the wave reduction gear transmission 1, the rotation pressing member 30 is configured such that the axis X2 that is the central axis of the pressing member 31 and the axis X3 that is the central axis of the pressing member 45 are orthogonal to the axis X4, respectively. And the axis X3 are disposed at positions orthogonal to each other when viewed from the direction of the axis X4, and have two pressing members 31 and pressing members 45, respectively. Stability can be improved. In the wave reduction gear 1, the contact portion 70 is movable (position can be adjusted) in the direction of the axis X1 in the case 2, but as a result of the movement of the contact portion 70, the output direction surface 70a and the fixed gear The pressing force can be kept constant even when the input direction surface 61b is not parallel.

  In the rotation pressing member 30, the pressing member 45 is preferably provided at a position different from the pressing member 31 by 90 degrees in the rotation direction of the axis X4. Further, the rotation pressing member 30 has two pressing members 45, and the pressing members 45 are arranged to face each other with the axis X4 interposed therebetween. Further, the rotation pressing member 30 has two pressing members 31, and the pressing members 31 are arranged to face each other with the axis X4 interposed therebetween. Therefore, the pressing member 45 can more stably follow the inclination of the output direction surface 70a, and the pressing member 31 can press the input direction surface 51b of the flexible gear 50 more stably. it can. Therefore, the amount of engagement between a part of the teeth 52 of the flexible gear 50 and a part of the teeth 62 of the fixed gear 60 can be made more constant over the entire circumference.

  As described above, according to the wave reduction device 1 according to the embodiment of the present invention, it is possible to allow an inclination at the time of assembling and to facilitate the assembling. Further, according to the wave reduction device 1 according to the embodiment of the present invention, the pressing amount can be kept constant over the entire circumference, and the operation stability can be improved.

  As described above, the embodiments of the present invention have been described, but the present invention is not limited to the above embodiments, and includes all aspects included in the concept of the present invention and the claims. In addition, the components may be appropriately selectively combined so as to achieve at least a part of the above-described problems and effects. For example, the shape, material, arrangement, size, and the like of each component in the above-described embodiment can be appropriately changed depending on the specific usage of the present invention.

  For example, the embodiment of the present invention has been described as an example in which the input shaft 10 and the rotation pressing member 30 are integrally formed as the wave reduction device 1, but the present invention is not limited to this, and is separately provided. The formed input shaft 10 and the rotation pressing member 30 may be connected to each other by a member such as a universal joint that can rotate integrally with different rotation shafts. Further, the input shaft 10 and the rotation pressing member 30 which are formed separately may be connected to each other by a spline structure or the like, which is movable in the direction of the axis X4 and is integrally rotatable. You may use together. Accordingly, the pressing member 45 can more stably follow the inclination of the output direction surface 70a, and the pressing member 31 can press the input direction surface 51b of the flexible gear 50 more stably. it can.

  DESCRIPTION OF SYMBOLS 1 ... Wave reduction gear, 2 ... Case, 3 ... Housing recess, 4 ... Disk part, 4a ... Output direction surface, 4b ... Input direction surface, 4c ... Through-hole, 5 ... Cylindrical part, 6 ... Flange part, 10 ... Input Shaft, 11: bearing, 11a: outer peripheral surface, 20: output shaft, 20a: end, 21a, 21b: flange portion, 21c: output direction surface, 22: screw hole, 23, 24: bearing, 23a, 24a: outer periphery Surface, 23b: input direction surface, 30: rotary pressing member, 30a: output direction surface, 30b: input direction surface, 31: pressing member, 32, 33: flat surface, 34, 35: bearing support portion, 34a, 35a ... Outer peripheral surface, 36, 37 ... ball bearing, 36a, 37a ... inner peripheral surface, 36b, 37b ... outer peripheral surface, 38, 39 ... flat surface, 40, 41 ... bearing support portion, 40a, 41a ... outer peripheral surface, 42, 43 ... Ball bearings, 42a 43a ... inner peripheral surface, 42b, 43b ... outer peripheral surface, 44 ... clearance space, 45 ... pressing member, 50 ... flexible gear, 51 ... flexible gear base, 51a ... output direction surface, 51b ... input direction surface, 51c, 51d: through hole, 52: teeth, 53: plate portion, 53a: output direction surface, 53b: input direction surface, 53c, 54: through hole, 55: bolt, 60: fixed gear, 61: fixed gear Substrate, 61a: output direction surface, 61b: input direction surface, 61c: through hole, 62: tooth, 63: flange portion, 70: contact portion, 70a: output direction surface, 70b: input direction surface, 70c: through hole

Claims (6)

An input shaft extending in the axial direction;
An output shaft extending in the axial direction;
A rotation pressing member connected to the input shaft,
A flexible gear having flexibility connected to the output shaft;
A fixed gear that is non-rotatable about the axis, facing the flexible gear in the axial direction,
A pressing surface which is a surface facing the output side in the axial direction,
The rotation reduction member is characterized in that the rotation pressing member rotates on the pressing surface and is movable in a ring around the axis. The flexible gear has a tooth forming surface that is a surface facing the output side in the axial direction, a pressed surface that is a surface facing the tooth forming surface, and an annular shape around the axis on the tooth forming surface. And a plurality of teeth arranged in
The fixed gear has a tooth forming surface facing the input side in the axial direction, and a plurality of teeth arranged on the tooth forming surface in a ring shape around the axis and opposed to the teeth of the flexible gear. And
The number of teeth of the flexible gear is different from the number of teeth of the fixed gear,
The rotation pressing member includes at least one pressing member that abuts against a pressed surface of the flexible gear from the input side to mesh a part of the teeth of the flexible gear with a part of the teeth of the fixed gear. Have
The pressing surface is provided on the input side relative to the pressing member of the rotation pressing member in the axial direction,
The rotation pressing member is provided at a position different from the pressing member around the axis, and has at least one pressing member that can rotate on the pressing surface and move in a ring around the axis. The wave reduction gear according to claim 1, wherein:   The wave reduction gear according to claim 2, wherein the pressing member is provided at a position different from the pressing member by 90 degrees in a rotation direction of the axis.   The wave reduction gear according to claim 2 or 3, further comprising two pressing members, wherein the pressing members are arranged to face each other across the axis.   The wave reduction gear according to any one of claims 2 to 4, further comprising two pressing members, wherein the pressing members are arranged to face each other across the axis. . The output shaft is rotatably supported on the fixed gear via a bearing,
The wave reduction gear according to any one of claims 1 to 5, wherein the flexible gear urges the output shaft and the bearing.

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