JP6131693B2 - Deceleration mechanism, drive device and robot device - Google Patents

Description

  The present invention relates to a speed reduction mechanism, a drive device, and a robot device.

  Conventionally, Harmonic Drive (registered trademark) is known as a speed reduction mechanism that has a small number of components and can provide a large speed reduction ratio. Since this reduction mechanism has a simple structure and a large reduction ratio, and can be made relatively small, it is used in a drive device such as a motor or a robot device having a robot hand.

Japanese Utility Model Publication No. 01-098353

However, the Harmonic Drive (registered trademark) has a drawback that it has low rigidity and is not suitable for transmission of high torque.
In view of the circumstances as described above, an object of the present invention is to provide a speed reduction mechanism, a drive device, and a robot device that can generate high torque.

  According to the first aspect of the present invention, there is provided a reduction mechanism that transmits a rotational force from the input shaft to the output shaft, provided in a part of the input shaft, and an eccentric portion that can rotate integrally with the input shaft; It is provided so that a part becomes a rotational force transmission part capable of transmitting rotational force to the output shaft, and the rotational force transmission part is sequentially changed with the rotation of the eccentric part. A speed reduction mechanism including a transmission unit that rotates the output shaft by being changed is provided.

  According to the second aspect of the present invention, there is provided a drive device including the speed reduction mechanism according to the first aspect of the present invention and a drive unit that rotates an input shaft provided in the speed reduction mechanism.

  According to a third aspect of the present invention, there is provided a robot apparatus that includes a moving body and a driving device that drives the moving body, and the driving device according to the second aspect of the present invention is mounted as the driving device. Is done.

  According to the present invention, it is possible to provide a speed reduction mechanism, a drive device, and a robot device that can generate high torque.

The perspective view which shows the structure of the deceleration mechanism which concerns on 1st embodiment. Sectional drawing which shows the structure of the deceleration mechanism which concerns on this embodiment. Sectional drawing which shows the structure of the deceleration mechanism which concerns on this embodiment. Sectional drawing which shows the structure of the deceleration mechanism which concerns on this embodiment. The graph which shows the characteristic of the deceleration mechanism which concerns on this embodiment. The figure which shows the operation | movement aspect of the deceleration mechanism which concerns on this embodiment. The figure which shows the operation | movement aspect of the deceleration mechanism which concerns on this embodiment. The figure which shows the operation | movement aspect of the deceleration mechanism which concerns on this embodiment. The figure which shows the operation | movement aspect of the deceleration mechanism which concerns on this embodiment. Sectional drawing which shows the structure of the deceleration mechanism which concerns on 2nd embodiment. The perspective view which shows the structure of the motor apparatus which concerns on 3rd embodiment. The schematic diagram which shows the structure of a robot hand. The figure which shows the structure of a part (eccentric part) of the deceleration mechanism which concerns on a modification. The figure which shows the structure of a part (transmission part) of the deceleration mechanism which concerns on a modification.

Embodiments of the present invention will be described below with reference to the drawings.
[First embodiment]
1 to 3 are schematic views showing the overall configuration of the speed reduction mechanism 100 according to the first embodiment of the present invention. FIG. 1 is a perspective view showing the configuration of the speed reduction mechanism 100. FIG. 2 is a diagram showing a configuration along a cross section including the AA line in FIG. 1.

  As shown in FIGS. 1 and 2, the speed reduction mechanism 100 transmits a rotational force from the input shaft S1 to the output shaft S2. The speed reduction mechanism 100 includes a housing 10, an input side bearing 20, an eccentric part 30, a transmission part 40, and an output side bearing 50. The input shaft S1 is connected to, for example, a motor device (not shown). The output shaft S2 is connected to a rotating object (not shown).

FIG. 3 is a diagram illustrating a configuration along the BB cross section in FIG. 2.
As shown in FIGS. 2 and 3, the input shaft S1 and the output shaft S2 rotate around the axis of the rotation axis AX. In the following description, the axial direction of the rotation axis AX may be expressed as the Z-axis direction. Thus, the input shaft S1 and the output shaft S2 are arranged concentrically. The input shaft S1 and the output shaft S2 are formed in a columnar shape, and are formed in the longitudinal direction in the axial direction of the rotation axis AX. The shapes of the input shaft S1 and the output shaft S2 may be other shapes such as a cylindrical shape, a column shape, or a cone shape.

  An enlarged diameter portion 60 is formed at the end of the output shaft S2 on the input shaft S1 side. The enlarged diameter portion 60 is a portion where the diameter of the output shaft S2 is larger than the other portions. Therefore, the enlarged diameter portion 60 has a cylindrical shape, and the central axis of the enlarged diameter portion 60 coincides with the rotation axis AX. The enlarged diameter part 60 can rotate integrally with the other part of the output shaft S2. An outer peripheral surface 60 c is formed on the outer periphery of the enlarged diameter portion 60. Both end sides in the axial direction of the rotation axis AX of the enlarged diameter portion 60 are formed in a rounded shape.

  The housing 10 is formed so as to surround the end of the input shaft S1, the end of the output shaft S2, the eccentric portion 30, and the transmission portion 40. The outer shape of the housing 10 is formed in a cylindrical shape centered on the rotation axis AX, for example.

  The input side bearing 20 is inserted between the input shaft S <b> 1 and the housing 10. The input side bearing 20 supports the input shaft S <b> 1 so that the input shaft S <b> 1 can rotate between the housing 10. As the input side bearing 20, for example, a bearing such as a ball bearing is used.

  The eccentric part 30 is provided in the edge part in the housing 10 among the input shafts S1. The eccentric part 30 is formed in a disk shape and is provided integrally with the input shaft S1. For example, a cam or the like is used as the eccentric portion 30. The eccentric part 30 is provided at a position where the center position in the axial direction view is deviated from the rotation axis AX. Therefore, when the input shaft S1 rotates, the eccentric portion 30 rotates eccentrically around the axis of the rotation axis AX.

The transmission unit 40 transmits the rotation of the input shaft S1 to the output shaft S2. The transmission part 40 has a bearing part 41, a cylindrical part 42, and a connection part 43.
The bearing part 41 is provided in the eccentric part 30. The bearing portion 41 includes an inner peripheral side member 41a attached to the outer peripheral surface of the eccentric portion 30, an outer peripheral side member 41b disposed to face the inner peripheral side member 41a, and the inner peripheral side member 41a and the outer peripheral side member. And a ball member 41c sandwiched between 41b. The outer peripheral side member 41 b of the bearing portion 41 is fixed to the inner peripheral surface of the first end portion 42 a of the cylindrical portion 42. For this reason, the bearing part 41 supports the eccentric part 30 rotatably with respect to the cylindrical part 42.

FIG. 4 is a diagram showing a configuration along a CC section in FIG.
As shown in FIGS. 2 to 4, the cylindrical portion 42 is formed in an annular shape so as to surround the outer peripheral surface 60 c of the enlarged diameter portion 60 in the output shaft S <b> 2. In the present embodiment, the cylindrical portion 42 is formed in a cylindrical shape, for example.

  In the axial direction of the rotation axis AX, the cylindrical portion 42 is formed to have a size larger than that of the enlarged diameter portion 60. Further, both ends of the cylindrical portion 42 are formed so as to protrude from both ends of the enlarged diameter portion 60 in the axial direction of the rotation axis AX. Thus, the cylindrical part 42 is arrange | positioned so that the enlarged diameter part 60 may be included as a part of output shaft S2.

  The cylindrical portion 42 has an inner peripheral surface 42c. The inner peripheral surface 42c is arranged so that a part thereof is in contact with a part of the outer peripheral surface 60c of the enlarged diameter portion 60 in the output shaft S2. The circumferential dimension of the inner circumferential surface 42c is larger than the circumferential dimension of the outer circumferential surface 60c. A contact portion 70 (see FIG. 2 or 4) between the inner peripheral surface 42c and the outer peripheral surface 60c serves as a rotational force transmission portion for transmitting rotation from the input shaft S1 to the output shaft S2. The contact portion 70 includes a portion (first contact portion 71) provided on the outer peripheral surface 60c and a portion (second contact portion 72) provided on the inner peripheral surface 42c (see FIG. 2 or FIG. 4).

  The inner peripheral surface 42c and the outer peripheral surface 60c are formed so that a predetermined frictional force is generated between them. The inner peripheral surface 42c and the outer peripheral surface 60c are formed so that the friction coefficient is substantially uniform in the circumferential direction.

  The cylindrical part 42 is formed in a mesh shape, for example. For this reason, the cylindrical part 42 has higher rigidity in the in-plane direction (circumferential direction or axial direction) than the rigidity in the radial direction. Moreover, the cylindrical part 42 is provided so that elastic deformation is possible with respect to the force of radial direction (direction perpendicular | vertical to the in-plane direction of the internal peripheral surface 42c). With respect to the force in the circumferential direction or the axial direction (direction parallel to the inner peripheral surface 42c) of the cylindrical portion 42, deformation is less likely than when the force is applied in the radial direction.

  Thus, the rigidity in the radial direction of the tubular portion 42 is lower than the rigidity in the circumferential direction of the tubular portion 42. For this reason, it is possible to temporarily increase the diameter of the cylindrical portion 42 by applying a force to the cylindrical portion 42 toward the outer peripheral surface 60 c of the enlarged diameter portion 60.

  In addition, the cylindrical portion 42 can be easily wound around the output shaft S2 with high accuracy (eg, no play). In addition, since both ends in the axial direction of the rotation axis AX are formed in a rounded shape in the enlarged diameter portion 60, the cylindrical portion 42 is pressed in a state of being curved so as to follow the shape of the enlarged diameter portion 60. Will be.

  As shown in FIG. 2, the connection portion 43 is provided at the second end portion 42 b of the tubular portion 42. The connection portion 43 is fixed inside the housing 10. The connecting portion 43 is formed using a material having higher rigidity than the cylindrical portion 42. For this reason, the connecting portion 43 is less likely to be deformed by an external force than the cylindrical portion 42. The connection part 43 is formed in an annular shape, for example. In the present embodiment, the connection portion 43 is formed in a ring shape. The center of the connecting portion 43 coincides with the rotation axis AX.

  Thus, the cylindrical part 42 formed in the cylindrical shape is connected to the bearing part 41 and the connection part 43. At this time, since the center of the connection portion 43 coincides with the rotation axis AX and the center of the bearing portion 41 is disposed at a position shifted from the rotation axis AX, the cylindrical portion 42 is connected to the connection portion from the bearing portion 41. 43 is held in a state of being inclined with respect to the rotation axis AX.

  Further, a part of the outer peripheral surface 60 c of the enlarged diameter portion 60 is formed so as to protrude from the outer peripheral side member 41 b of the bearing portion 41 to the outer peripheral side when viewed in the axial direction of the rotation axis AX. That is, a part of the outer peripheral surface 60 c of the enlarged diameter portion 60 is formed so as to protrude from the portion of the outer peripheral side member 41 b of the bearing portion 41 that is closest to the rotation axis AX to the outer peripheral side. For this reason, a part of the cylindrical portion 42 held from the bearing portion 41 to the connection portion 43 is pressed by the outer peripheral surface 60 c of the enlarged diameter portion 60.

  For this reason, the cylindrical portion 42 is disposed in an elastically deformed state, and in a state where a part of the inner peripheral surface 42 c is in contact with a part of the outer peripheral surface 60 c of the enlarged diameter portion 60. That is, the first contact portion 71 of the cylindrical portion 42 constitutes the contact portion 70 in a state where tension is generated by elastic deformation between the first contact portion 71 and the second contact portion 72 of the enlarged diameter portion 60 (output shaft S2). doing. Thus, the cylindrical part 42 is arrange | positioned in the state which can transmit rotational force between the enlarged diameter parts 60. FIG.

Next, the principle of torque transmission of the speed reduction mechanism 100 configured as described above will be described.
As shown in FIG. 4, a tension T <b> 1 acts on one end portion in the circumferential direction of the first contact portion 71 of the cylindrical portion 42 in the tangential direction of the outer peripheral surface 60 c of the enlarged diameter portion 60. In addition, a tension T2 acts on the other end portion in the circumferential direction of the first contact portion 71 in a direction tangential to the outer peripheral surface 60c and opposite to the direction of the tension T1. According to Euler's friction belt theory, when the tension T1 and the tension T2 satisfy the following [Equation 1], a frictional force is generated between the cylindrical portion 42 and the outer peripheral surface 60c, and the cylindrical portion 42 is against the outer peripheral surface 60c. It is possible to move in the circumferential direction together with the outer peripheral surface 60c in a state where no slip occurs (rotational force transmission state). In this case, torque is transmitted from the cylindrical portion 42 to the enlarged-diameter portion 60 by the cylindrical portion 42 moving in the circumferential direction together with the outer peripheral surface 60c. However, in [Equation 1], μ is an apparent friction coefficient between the cylindrical portion 42 and the enlarged diameter portion 60, and θ is an effective winding angle of the cylindrical portion 42.

At this time, the effective tension contributing to torque transmission is represented by (T1-T2). When the effective tension (T1-T2) is obtained based on the above [Equation 1], [Equation 2] is obtained. [Equation 2] is an expression representing an effective tension using T1.

From the above [Equation 2], it can be seen that the torque transmitted to the enlarged diameter portion 60 is uniquely determined by the tension T1. The coefficient portion of T1 on the right side of [Formula 2] depends on the friction coefficient μ between the cylindrical portion 42 and the outer peripheral surface 60c and the effective winding angle θ of the cylindrical portion 42, respectively. FIG. 6 is a graph showing the relationship between the effective winding angle θ and the value of the coefficient portion when the friction coefficient μ is changed.
The horizontal axis of the graph indicates the effective winding angle θ, and the vertical axis of the graph indicates the value of the coefficient portion.

  As shown in FIG. 5, for example, when the friction coefficient μ is 0.3, the value of the coefficient portion is 0.8 or more when the effective winding angle θ is 300 ° or more. From this, when the friction coefficient μ is 0.3, by setting the effective winding angle θ to 300 ° or more, the force of 80% or more of the tension T1 acting on the first contact portion 71 is increased in the diameter-enlarged portion 60. It turns out that it contributes to the torque of (output shaft S2). In addition to the winding angle, it is estimated from the graph of FIG. 5 that, for example, the value of the coefficient portion increases as the friction coefficient between the cylindrical portion 42 and the outer peripheral surface 60c increases. Thus, the magnitude of the torque is uniquely determined by the tension T1 acting on the first contact portion 71, and it can be seen that it is independent of the moving distance of the cylindrical portion 42, for example.

  Further, due to the deformation of the cylindrical portion 42, a part of the inner peripheral surface 42 c (surface contact portion) of the cylindrical portion 42 and a part of the outer peripheral surface 60 c (surface contact portion) of the enlarged diameter portion 60 face each other. Contact with. The contact portion of the surface has, for example, a predetermined width larger than the width due to line contact in the circumferential direction of the surface. The speed reduction mechanism 100 according to the present embodiment can easily bring the inner peripheral surface 42c into contact with most of the outer peripheral surface 60c, and therefore can generate a large frictional force and output a high torque.

  Therefore, between the first contact portion 71 and the second contact portion 72, the winding angle of the cylindrical portion 42 with respect to the enlarged diameter portion 60 (output shaft S2) (eg, 180 °, an angle greater than 180 °, 200 Friction force works according to (°, 300 °, 360 ° or more). Further, since tension is generated in the cylindrical portion 42, the inner peripheral surface 42c is pressed against the outer peripheral surface 60c. For this reason, the frictional force is further increased.

  In addition, the cylindrical part 42 has the first contact part 71 and the second contact when the rotational force exceeding the dynamic frictional force between the first contact part 71 and the second contact part 72 is input to the output shaft from the outside. You may arrange | position so that a slip may arise between the parts 72. FIG. Thereby, transmission of torque more than a certain level can be suppressed. In this case, the slip can be detected by disposing the detection unit 81 (broken line portion in FIG. 2) on the input shaft S1 and disposing the detection unit 82 (broken line portion in FIG. 2) on the output shaft S2.

Next, the operation of the speed reduction mechanism 100 configured as described above will be described.
First, as shown in FIG. 6, the input shaft S <b> 1 is rotated by a motor device (not shown) or the like in a state where tension is generated with respect to the cylindrical portion 42. By the rotation of the input shaft S1, the eccentric part 30 provided integrally with the input shaft S1 rotates eccentrically about the rotation axis AX. Due to the eccentric rotation of the eccentric portion 30, the inner peripheral side member 41 a of the bearing portion 41 connected to the eccentric portion 30 rotates eccentrically according to the eccentric portion 30.

  On the other hand, the outer peripheral side member 41b connected with the ball member 41c interposed therebetween does not rotate (non-rotating state) because the outer peripheral side is fixed to the cylindrical portion 42. On the other hand, since the inner peripheral side member 41a is eccentrically rotated, the outer peripheral side member 41b rotates around the rotation axis AX so as to follow the track of the inner peripheral side member 41a. As described above, due to the rotation of the input shaft S1, the outer peripheral member 41b rotates around the rotation axis AX in a non-rotating state.

  Due to the movement of the outer peripheral member 41b, the contact portion 70 between the inner peripheral surface 42c of the cylindrical portion 42 and the outer peripheral surface 60c of the enlarged diameter portion 60 moves. By moving the contact portion 70, as shown in FIG. 7, the cylindrical portion 42 has the outer peripheral surface 60c and the inner peripheral surface 42c kept in contact with each other at the first contact portion 71 and the second contact portion 72. It moves around in the counterclockwise direction when viewed from the direction. At this time, the cylindrical portion 42 does not rotate around the Z axis.

  Due to the circular movement of the tubular portion 42, the deformation of the tubular portion 42 is sequentially performed along the circumferential direction of the inner peripheral surface 42c. Further, in the state where the frictional force is generated between the first contact portion 71 and the second contact portion 72 due to the circular movement of the tubular portion 42, the first contact portion 71 and the second contact portion 72 are in the + Z direction. It gradually changes to a position shifted by 90 ° in the clockwise direction as viewed.

  Since the circumferential length of the outer circumferential surface 60c is shorter than the circumferential length of the inner circumferential surface 42c, the positions of the first contact portion 71 and the second contact portion 72 are shifted by 90 ° clockwise as viewed in the + Z direction. Change amount t1 of the first contact portion 71 is smaller than the change amount t2 of the contact portion on the inner peripheral surface 42c.

  For this reason, a relative displacement is generated between the outer peripheral surface 60c and the inner peripheral surface 42c by the difference (t1-t2) in the amount of change. As a result, the diameter-enlarged portion 60 rotates in the opposite direction (clockwise direction in FIG. 7) to the circumferential direction of the tubular portion 42 by the amount of rotation corresponding to the difference (t1-t2) in the change amount.

  When the input shaft S1 further rotates, as shown in FIG. 8, the cylindrical portion 42 has the outer peripheral surface 60c and the inner peripheral surface 42c in contact with each other at the first contact portion 71 and the second contact portion 72, Moves counterclockwise in the + Z direction view. As a result, the diameter-enlarged portion 60 has a rotational direction equivalent to the difference (t1-t2) between the change amount of the first contact portion 71 and the change amount of the second contact portion 72, and the circumferential direction of the tubular portion 42. Rotates in the opposite direction (clockwise direction in FIG. 8).

  When the input shaft S1 further rotates, as shown in FIG. 9, the cylindrical portion 42 is such that the outer peripheral surface 60c and the inner peripheral surface 42c remain in contact with each other at the first contact portion 71 and the second contact portion 72. Moves counterclockwise in the + Z direction view. As a result, the diameter-enlarged portion 60 has a rotational direction equivalent to the difference (t1-t2) between the change amount of the first contact portion 71 and the change amount of the second contact portion 72, and the circumferential direction of the tubular portion 42. Rotates in the opposite direction (clockwise direction in FIG. 9).

  When the input shaft S1 further rotates, the cylindrical portion 42 has a counterclockwise direction when viewed in the + Z direction while the outer peripheral surface 60c and the inner peripheral surface 42c are in contact with each other at the first contact portion 71 and the second contact portion 72. And the enlarged diameter portion 60 rotates in a direction opposite to the circumferential direction of the cylindrical portion 42 by a rotation amount corresponding to the difference between the change amount of the first contact portion 71 and the change amount of the second contact portion 72. (See FIG. 6).

  As described above, since the speed reduction mechanism 100 according to the present embodiment has the above-described configuration, the cylindrical portion 42 is easy to wind around the enlarged diameter portion 60, and the winding angle is large. Therefore, the outer peripheral surface 60c and the inner peripheral surface 42c. A large frictional force can be generated between the two. Thereby, high torque can be generated.

[Second Embodiment]
Next, a second embodiment of the present invention will be described.
FIG. 10 is a cross-sectional view showing the configuration of the speed reduction mechanism 200 according to the present embodiment.
As shown in FIG. 10, the speed reduction mechanism 200 transmits a rotational force from the input shaft S1 to the output shaft S2. The speed reduction mechanism 200 includes a housing 210, an input side bearing 220, an eccentric part 230, a transmission part 240, and an output side bearing 250. The housing 210 is formed in a cylindrical shape. The eccentric part 230 and the transmission part 240 are arranged inside the housing 210.

  The transmission unit 240 includes a friction roller 241, a mesh belt 242, a flexible coupling 243, and a fixing unit 244. The friction roller 241 is fixed to the outer peripheral surface of the eccentric part 230 via the bearing 241a. The friction roller 241 is supported so as to be independently rotatable with respect to the eccentric portion 230.

  The mesh belt 242 is disposed along the inner peripheral surface of the housing 210, and is formed in a cylindrical shape, for example. The mesh belt 242 is formed to be elastically deformable in the radial direction. A part of the friction roller 241 is pressed against a part of the mesh belt 242 in the circumferential direction. The mesh belt 242 is in an elastically deformed state when a part of the friction roller 241 is pressed. Further, since tension is applied to a portion of the mesh belt 242 that contacts a part of the friction roller 241, the mesh belt 242 is in a state of transmitting a rotational force to the friction roller 241.

  The flexible coupling 243 connects the friction roller 241 and the output shaft S2. The flexible coupling 243 is formed in a bellows shape, for example. The rigidity of the flexible coupling 243 in the circumferential direction is set so as not to be deformed by the rotation of the friction roller 241. Thereby, the rotation of the friction roller 241 can be transmitted to the output shaft S2. Further, the flexible coupling 243 is formed to be deformable in the axial direction of the rotation axis AX.

Next, the operation of the speed reduction mechanism 200 configured as described above will be described.
When the input shaft S1 is rotated, the eccentric part 230 provided integrally with the input shaft S1 rotates. The friction roller 241 attached to the eccentric part 230 rotates around the axis of the rotation axis AX by the eccentric rotation of the eccentric part 230 without rotating. At this time, the friction roller 241 circulates around the axis of the rotation axis AX while being in a rotational force transmission state with the mesh belt 242. The circumferential dimension of the inner surface due to the deformation of the mesh belt 242 is larger than the circumferential dimension of the outer periphery of the friction roller 241. Therefore, when the friction roller 241 rotates around the axis of the rotation axis AX, the friction roller 241 rotates in a direction opposite to the direction of the rotation by the circumferential dimension difference.

  This rotation is transmitted to the output shaft S2 via the flexible coupling 243. Since the flexible coupling 243 can be deformed in the axial direction of the rotation axis AX, the flexible coupling 243 is deformed according to the revolving motion of the friction roller 241. For this reason, the stress of the circular motion of the friction roller 241 is absorbed.

  As described above, according to the present embodiment, since the mesh belt 242 is easily wound around the friction roller 241 and the winding angle is large because the configuration as described above is provided, the outer peripheral surface 241c of the friction roller 241 and the mesh belt 242 are provided. A large frictional force can be generated between the inner peripheral surface 242c of the first and second inner peripheral surfaces 242c. Thereby, high torque can be generated.

[Third embodiment]
Next, a third embodiment of the present invention will be described.
FIG. 11 is a cross-sectional view illustrating a configuration of the drive device ACT according to the present embodiment.
As shown in FIG. 11, the drive device ACT includes a speed reduction mechanism 300 and a motor device MTR. The driving device ACT rotates the input shaft S1 and transmits a rotational force to the output shaft S2. The speed reduction mechanism 300 includes a housing 310, an eccentric part 330, a transmission part 340, and an output side bearing 350. The housing 310 is formed in a cylindrical shape. A motor device MTR is attached to the housing 310. In addition, the eccentric portion 330 and the transmission portion 340 are disposed inside the housing 310.

  The transmission unit 340 includes a friction roller 341, a mesh belt 342, a flexible coupling 343, and a fixing unit 344. About the structure of the transmission part 340, it is the same structure as 2nd embodiment.

  As described above, according to the present embodiment, the mesh belt 342 is easily wound around the friction roller 341 and the winding angle is large, so that the gap between the outer peripheral surface 341c of the friction roller 341 and the inner peripheral surface 342c of the mesh belt 342 is between. A large frictional force can be generated. As a result, a high torque can be generated from the input shaft S1 to the output shaft S2, and thus a small motor device MTR capable of outputting a high torque can be obtained.

[Fourth embodiment]
Next, a fourth embodiment of the present invention will be described.
FIG. 12 is a diagram illustrating a configuration of a part (tip of a finger portion) of a robot apparatus RBT including the driving apparatus ACT described in the third embodiment.

  As illustrated in FIG. 12, the robot apparatus RBT includes a terminal node portion 101, a middle node portion 102, and a joint portion 103, and the terminal node portion 101 and the middle node portion 102 are connected via the joint portion 103. It has become. The joint portion 103 is provided with a shaft support portion 103a and a shaft portion 103b. The shaft support portion 103 a is fixed to the middle joint portion 102. The shaft portion 103b is supported in a state of being fixed by the shaft support portion 103a.

  The end node portion 101 includes a connecting portion 101a and a gear 101b. The shaft portion 103b of the joint portion 103 is penetrated through the connecting portion 101a, and the end node portion 101 is rotatable with the shaft portion 103b as a rotation axis. The gear 101b is a bevel gear fixed to the connecting portion 101a. The connecting portion 101a rotates integrally with the gear 101b.

  The middle joint portion 102 includes a housing 102a and a driving device ACT. As the driving device ACT, the driving device ACT described in the above embodiment can be used. The driving device ACT is provided in the housing 102a. A rotating shaft member 104a is attached to the driving device ACT. A gear 104b is provided at the tip of the rotating shaft member 104a. The gear 104b is a bevel gear fixed to the rotating shaft member 104a. The gear 104b is in mesh with the gear 101b.

  In the robot apparatus RBT configured as described above, the rotation shaft member 104a is rotated by the drive of the drive device ACT, and the gear 104b is rotated integrally with the rotation shaft member 104a.

  The rotation of the gear 104b is transmitted to the gear 101b meshed with the gear 104b, and the gear 101b rotates. As the gear 101b rotates, the connecting portion 101a also rotates, whereby the end node portion 101 rotates about the shaft portion 103b.

  As described above, according to the present embodiment, by mounting the driving device ACT that can output the rotation of the high torque with the low voltage, the driving force can be efficiently transmitted, and the end node portion 101 is rotated. Can be made. Furthermore, in the present embodiment, since the driving device ACT is configured to be able to efficiently transmit the driving force, it is possible to perform a stable operation.

The technical scope of the present invention is not limited to the above-described embodiment, and appropriate modifications can be made without departing from the spirit of the present invention.
For example, in the above-described embodiment, the configuration in which the input shaft S1 and the output shaft S2 are concentrically arranged when viewed in the axial direction of the rotation axis AX is described as an example. Different arrangements are possible.

  Moreover, in the said embodiment, although demonstrated taking the example of the structure by which the cylindrical part 42 of the transmission part 40 was formed in cyclic | annular form, it is not restricted to this. For example, as long as the Euler friction belt theory can be applied, the shape may be other shapes, for example, a belt shape or a linear shape.

  Moreover, in the said embodiment, the cylindrical part 42 of the transmission part 40 is arrange | positioned so that a part of output shaft S2 may be included, and a rotational force transmission part is the structure provided in the internal peripheral surface of the transmission part 40. However, the present invention is not limited to this. For example, the output shaft S2 may be configured in a cylindrical shape, and the transmission unit 40 may be configured in the output shaft S2.

  Moreover, in the said embodiment, although the structure where the amount of eccentricity of the eccentric part 30 formed in input shaft S1 was constant was mentioned as an example, it demonstrated and it is not restricted to this. For example, as illustrated in FIG. 13, the eccentricity of the eccentric portion 430 may be variable. FIG. 13 is a cross-sectional view showing the configuration of the eccentric portion 430. As shown in FIG. 13, the eccentric portion 430 includes a disk-shaped first member 430a fixed to the input shaft S1, and a disk-shaped second member 430b disposed around the first member 430a. Have. The first member 430a has a circular opening formed at a position shifted from the center, and the input shaft S1 is fixed to the opening. The first member 430a is disposed in a circular opening formed at a position deviated from the center of the second member 430b so as to be rotatable without a gap. With this configuration, by rotating the first member 430a with respect to the second member 430b, the distance from the center of the second member 430b to the center of the input shaft S1 changes.

  Moreover, in the said embodiment, although the structure using the transmission part formed in the belt shape was mentioned as an example and demonstrated, it is not restricted to this. FIG. 14 is a diagram illustrating a configuration of a part (transmission unit) of a speed reduction mechanism according to a modification. As shown in FIG. 14, the transmission unit 440 may have a configuration in which the internal teeth (flat portion) 441 a of the internal gear 441 and the external teeth (flat portion) 442 a of the external gear 442 are engaged. . In this case, the engaging surface on which the inner teeth 441a and the outer teeth 442a are engaged becomes the rotational force transmitting portion.

30, 230, 330, 430 ... eccentric part 40, 240, 340, 440 ... transmission part 41 ... bearing part 42 ... cylindrical part 43 ... connection part 60 ... enlarged diameter part 60c ... outer peripheral surface 70 ... contact part 71 ... first Contact part 72 ... Second contact part 81 ... Detection part 82 ... Detection part 100, 200, 300 ... Deceleration mechanism 241, 341 ... Friction roller 242, 342 ... Mesh belt 243, 343 ... Flexible coupling 244, 344 ... Fixed part S1 ... Input shaft S2 ... Output shaft AX ... Rotary shaft ACT ... Drive device MTR ... Motor device RBT ... Robot device

Claims (13)

A speed reduction mechanism that transmits rotational force from the input shaft to the output shaft,
An eccentric portion provided on a part of the input shaft and rotatable integrally with the input shaft;
The rotational force transmission part is provided so that a part thereof is a rotational force transmission part capable of transmitting rotational force to the output shaft, and the rotational force transmission part is sequentially changed as the eccentric part rotates. A transmission part that rotates the output shaft by sequentially changing the transmission part ,
The transmission part is formed in an annular shape and is arranged so as to include a part of the output shaft,
The rotational force transmitting portion, the speed reduction mechanism that provided on the inner peripheral surface of the transmission portion. The speed reduction mechanism according to claim 1, wherein the input shaft and the output shaft are arranged concentrically when viewed in the axial direction of the rotating shaft. The speed reduction mechanism according to claim 1, wherein the transmission portion is arranged such that the rotational force transmission portion moves in a circumferential direction of the inner peripheral surface as the eccentric portion rotates. The transmission unit, the deceleration according to any one of claims 1 to 3, which is arranged to move in a non-rotational state in the rotation direction of the input shaft with the rotation of the eccentric portion mechanism. The speed reduction mechanism according to any one of claims 1 to 4 , wherein the transmission portion is arranged such that the rotational force transmission portion presses the output shaft in a radial direction of the output shaft. The transmission portion slips between the rotational force transmission portion and the output shaft when a rotational force exceeding the dynamic friction force between the rotational force transmission portion and the output shaft is input from the outside to the output shaft. The speed reduction mechanism according to any one of claims 1 to 5 , wherein the speed reduction mechanism is arranged so as to occur. The speed reduction mechanism according to claim 6 , wherein the output shaft is provided with a detection unit that detects the slip. The speed reduction mechanism according to any one of claims 1 to 7 , wherein the transmission portion has a flat portion at least in part and can be arranged so that the flat portion becomes the rotational force transmission portion. . The speed reduction mechanism according to any one of claims 1 to 8 , wherein the transmission portion is formed such that the rotational force transmission portion has elasticity. The speed reduction mechanism according to any one of claims 1 to 9 , wherein the transmission unit is formed in a mesh shape. The speed reduction mechanism according to any one of claims 1 to 10 , wherein the eccentric part is coupled to the transmission part via a bearing part. The speed reduction mechanism according to any one of claims 1 to 11 , a drive unit that rotates the input shaft,
A drive device comprising: A moving object,
A driving device for driving the movable body,
A robot apparatus in which the drive apparatus according to claim 12 is mounted as the drive apparatus.

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