Rotational reduction transmission device

Abstract

A rotation reduction transmission device is provided that reduces manufacturing costs, improves durability and reliability, and achieves miniaturization and improved rotation transmission efficiency. The device comprises: a cam body integral with a rotation input portion; an elliptical shaft portion with a rotating body interposed between an inner ring disposed on the outer circumference and a flexible outer ring; an inner gear portion having an internal gear formed on the inner circumference; a flexible gear portion having an external gear and a plurality of transmission pins, the external gear having a smaller number of teeth than the internal gear and meshing with the internal gear at multiple meshing positions when attached to the outer circumference of the elliptical shaft portion; and a rotation output mechanism comprising an output plate portion having an engagement portion formed with engagement holes for engagement with the transmission pins. The engagement holes are spaced at predetermined intervals in the circumferential direction and allow for displacement of the transmission pins in the circumferential and / or radial directions during rotation transmission.

Description

[0001] This application is a divisional application of the invention patent application with the application date of September 7, 2017, application number 201710799694.3, and invention name “Rotational reduction transmission device”. Technical Field

[0002] The present invention relates to a rotational speed reduction transmission device that is built into a robot or the like and decelerates input rotational motion and outputs the decelerated rotational motion. Background Art

[0003] Typically, industrial robots are installed in production lines in factories requiring mass production, consisting of multiple arms connected by joint mechanisms. These joint mechanisms rotatably connect the ends of any arm to the ends of other arms and include a rotational reduction transmission device that reduces the rotational speed of the drive motor built into any arm to approximately 1 / 100 to 1 / 200, using the reduced rotational output to drive the rotation of the other arms. Therefore, this rotational reduction transmission device requires high-precision positioning control, angle control, speed control, and other features.

[0004] In the past, as a rotational reduction transmission device to meet such requirements, a reducer based on a wave gear mechanism called harmonic drive (registered trademark) has been widely used. As robots or robot-related devices having this wave gear mechanism, for example, the prime mover disclosed in Patent Document 1, the wrist mechanism of an industrial robot disclosed in Patent Document 2, and the multi-joint robot disclosed in Patent Document 3 are known.

[0005] In this case, the prime mover disclosed in Patent Document 1 includes: a cup-shaped housing; a harmonic reducer, which is formed by supporting an annular circular spline on the inner periphery of the housing in a rotatable manner, and fixing a cup-shaped flexible spline arranged on the inner side of the circular spline and engaged with the circular spline by a wave generator to the housing; and a hydraulic motor, which is formed by fixing one end of a support shaft to the housing, and arranging a shell that rotates around the support shaft inside the flexible spline, and providing a wave generator in the shell. The prime mover is constructed to be able to extract a rotational output from the circular spline.

[0006] In addition, the wrist mechanism of the industrial robot disclosed in Patent Document 2 is provided with: a third axis that rotates the entire wrist supported on the arm so as to be rotatable around the arm axis as the center; a second axis that is supported on the third axis so as to tilt the front end of the wrist supported so as to be rotatable around an axis at a right angle to the third axis; and a first axis that is supported on the second axis so as to rotate the tool holding portion of the front end of the wrist supported so as to be rotatable around an axis at a right angle to the second axis, and is constructed so that the first and second axes are decelerated inside the wrist by a reducer arranged to overlap on the same center axis, and the third axis is decelerated in advance outside the wrist.

[0007] Furthermore, the multi-joint robot disclosed in Patent Document 3 has at least two control arms and two reducers arranged opposite to each other on the same axis at the joints of the two control arms. The multi-joint robot is composed of first and second harmonic drive reducers, and the first and second harmonic drive reducers have: a common circular spline for fixing the two reducers to the joint of one control arm; and a bracket, which is mounted on one end of the common circular spline in a manner capable of rotating relative to the circular spline and is connected to the joint of the other control arm.

[0008] Prior art literature

[0009] Patent Literature

[0010] [Patent Document 1] Japanese Patent Application Laid-Open No. 60-098246

[0011] [Patent Document 2] Japanese Patent Application Laid-Open No. 61-146490

[0012] [Patent Document 3] Japanese Patent Application Laid-Open No. 64-011777 Summary of the Invention

[0013] Problems to be solved by the invention

[0014] However, the above-mentioned conventional rotation reduction transmission device having a wave gear mechanism has the following problems.

[0015] First, the main components include a flexible spline, a wave generator, and a circular spline. The flexible spline is formed into a cup shape using a thin metal elastic plate. A gear portion formed on the outer periphery of the elliptical opening meshes with a gear portion formed on the inner periphery of the fixed circular spline. Therefore, the integrally formed cup-shaped flexible spline must be manufactured as a highly precise component, making its manufacture difficult and unavoidable, resulting in high costs. Furthermore, the flexible spline is prone to metal fatigue and malfunctions with use, making it difficult to maintain durability. As a result, conventional wave gear mechanisms significantly increase both initial and operating costs.

[0016] Secondly, a gear portion is formed on the outer periphery of the opening portion in the cup-shaped flexible spline, and the gear portion is deformed by an elliptical wave generator, and the output shaft for outputting the reduced rotation is connected to the center of the bottom. Therefore, in order for the flexible spline to function, it is necessary to ensure the axial length of the flexible spline to a certain extent, and there is a limit in achieving the thinning (miniaturization) of the overall structure of the reduction transmission device.

[0017] Third, because the flexible spline is cup-shaped overall and the output shaft is connected to the center of the bottom, with one end closed, it is difficult to secure space for routing connecting cables. In particular, robots have numerous joint mechanisms and a large number of built-in drive motors to achieve a wide range of movements. Therefore, the number of connecting cables connecting these drive motors to the robot controller must be at least the same as the number of drive motors, and this number of connecting cables must be routed. Therefore, there is room for further improvement in terms of securing space for routing a large number of connecting cables.

[0018] An object of the present invention is to provide a rotation reduction transmission device that solves the problems existing in the above-mentioned background art.

[0019] Means used to solve problems

[0020] In order to solve the above-mentioned problems, the rotation reduction transmission device 1 of the present invention is a rotation reduction transmission device that reduces the speed of input rotational motion and outputs the same, and is characterized in that it comprises: a rotation input portion 2 that inputs rotational motion; a cam body portion 3c that rotates integrally with the rotation input portion 2, and an elliptical shaft portion 3 formed by interposing a plurality of rotating bodies 3bm between an inner wheel 3bi and a flexible outer wheel 3bo arranged along the outer periphery of the cam body portion 3c; an inner gear portion 5 that has an inner gear 5g formed on the inner periphery and is fixed in position; a flexible gear portion 4 that has an outer gear 4g and a plurality of transmission pin portions 4p, the outer gear 4g being formed along the circumferential direction Ff of the outer periphery and having a smaller number of teeth than the inner gear 5g, and being attached to the elliptical shaft portion 3 When on the outer circumference, the external gear 4g meshes with the internal gear 5g at multiple meshing positions T on the circumferential direction Ff, and the multiple transmission pin portions 4p protrude from the side and are arranged at specified intervals along the circumferential direction Ff; and a rotation output mechanism 6, which has an output plate portion 7 provided with a locking portion 7s, the locking portion 7s is for each transmission pin portion 4p to engage, and is arranged at specified intervals along the circumferential direction Ff, and allows the transmission pin portion 4p to be displaced in the circumferential direction Ff and / or radial direction Fd when rotation transmission is performed, the locking portion is composed of a multi-directional locking hole, which is formed on the output plate portion, always abuts against the circumferential surface of the transmission pin portion, and allows the transmission pin portion to be displaced in the circumferential direction and the radial direction of the output plate portion.

[0021] In this case, according to a preferred embodiment of the invention, the transmission pin portion 4p can be composed of a transmission pin body 4pm protruding from the flexible gear portion 4 and a transmission roller 4pr supported at a central position for free rotation about the transmission pin body 4pm, and the output plate portion 7 can be formed in an annular shape. Meanwhile, the engaging portion 7s can be composed of a multi-directional engaging hole 7sm formed in the output plate portion 7, which constantly contacts the circumferential surface of the transmission pin portion 4p and allows displacement of the transmission pin portion 4p in both the circumferential direction Ff and the radial direction Fd of the output plate portion 7. Alternatively, the engaging portion 7s can be composed of an elastic engaging portion 7sd, which is elastically displaceable in the circumferential direction Ff by forming a one-way engaging hole 7ss protruding from the output plate portion 7 in the radial direction Fd, constantly contacting the circumferential surface of the transmission pin portion 4p, and allowing displacement of the transmission pin portion 4p in the radial direction Fd. In this case, the output plate portion 7 can be constructed by stacking multiple elastic plates 7p having a predetermined thickness Ls in the axial direction Fs. Meanwhile, the rotational input portion 2 comprises a cylindrical input rotating body 11. The inner square of the inner circumferential surface 11i is defined as a routing space S for cables Ka, Kb, etc., and at least the cam body 3c of the elliptical shaft portion 3 is provided on the outer circumferential surface 11o. Furthermore, the flexible gear portion 4 can mesh with the internal gear 5g of the inner gear portion 5 at two meshing positions T that are 180° apart.

[0022] Effects of the Invention

[0023] According to the rotation reduction transmission device 1 of the present invention having such a structure, the following remarkable effects are obtained.

[0024] (1) Since there is no need to use thin-walled metal elastic plates to form the overall shape into a cup as in the past, the flexible spline can be easily manufactured, thereby achieving a significant reduction in manufacturing costs. In addition, metal fatigue and malfunction can be greatly reduced, thereby achieving improved durability and reliability, etc., and achieving a significant reduction in both initial cost and operating cost.

[0025] (2) Since the conventional flexible spline is not required, the size of the installation space in the axial direction Fs can be reduced. Therefore, the overall structure can be made thinner, and further miniaturization can be achieved, especially for industrial robots, etc., where miniaturization has previously been limited.

[0026] (3) In a preferred manner, when the transmission pin portion 4p is constructed, if it is composed of a transmission pin body 4pm protruding from the flexible gear portion 4, and a transmission roller 4pr supported at a center position and rotatable about the transmission pin body 4pm as an axis, the contact friction between the transmission pin portion 4p and the engaging hole 7sh when the transmission pin portion 4p is engaged with the engaging hole 7sh can be reduced. Therefore, the rotation transmission from the flexible gear portion 4 to the output plate portion 7 can be carried out efficiently and stably, and unnecessary heat generation and consumption can be eliminated, thereby improving reliability in long-term use.

[0027] (4) Preferably, if the output plate portion 7 is formed into a ring shape, it is possible to ensure wiring space for the cables Ka, Kb, etc., and, in particular, by combining it with the input rotating body 11 formed into a cylindrical shape, it can contribute to the simplification and high rigidity of the overall structure.

[0028] (5) In a preferred manner, when the engaging portion 7s is formed, if it is composed of a multi-directional engaging hole 7sm, the multi-directional engaging hole 7sm is formed in the output plate portion 7, is always in contact with the circumferential surface of the transmission pin portion 4p, and allows the displacement of the transmission pin portion 4p in the circumferential direction Ff and the radial direction Fd of the output plate portion 7, then it can be said that the displacement of the transmission pin portion 4p in the circumferential direction Ff and the radial direction Fd generated at different positions in the circumferential direction Ff relative to the engaging hole 7sh can be absorbed by a cam method. Therefore, the useless stress generated when the engaging hole 7sh and the transmission pin portion 4p are engaged can be eliminated, and stable and smooth rotation transmission from the transmission pin portion 4p to the output plate portion 7 can be performed. In particular, high-precision rotation transmission based on improved rigidity can be performed.

[0029] (6) In a preferred manner, when constituting the engaging portion 7s, if it is constituted by an elastic engaging portion 7sd, the elastic engaging portion 7sd can be elastically displaced in the circumferential direction Ff by forming a one-way engaging hole 7ss. The one-way engaging hole 7ss is formed to protrude from the output plate portion 7 in the radial direction Fd, and is always in contact with the circumferential surface of the transmission pin portion 4p, and allows the displacement of the transmission pin portion 4p in the radial direction Fd. It can be said that the displacement of the transmission pin portion 4p at different positions in the circumferential direction Ff relative to the engaging hole 7sh, especially in the circumferential direction Ff, can be elastically absorbed. Therefore, the useless stress generated when the engaging hole 7sh and the transmission pin portion 4p are engaged can be eliminated, and stable and smooth rotation transmission from the transmission pin portion 4p to the output plate portion 7 can be performed. In particular, since it is not related to the processing accuracy, it can be easily implemented at a low cost.

[0030] (7) In a preferred manner, when constructing the output plate portion 7, if a plurality of elastic plates 7p having a predetermined thickness Ls are stacked in the axial direction Fs, appropriate elasticity can be ensured even when the output plate portion 7 is relatively thick, thereby enabling appropriate rotation transmission from the transmission pin portion 4p to the output plate portion 7.

[0031] (8) In a preferred manner, when forming the rotation input portion 2, if a cylindrical input rotating body 11 is used, the inner side of the inner peripheral surface 11i of the input rotating body 11 is used as the wiring space S for the cables Ka, Kb..., and at least the cam main body portion 3c of the elliptical shaft portion 3 is provided on the outer peripheral surface 11o, then the wiring space for the cables Ka, Kb... can be ensured. Therefore, even if the number of cables Ka... is large, the overall complexity can be avoided together with other peripheral structures.

[0032] (9) In a preferred manner, if the flexible gear portion 4 is meshed with the inner gear 5g of the inner gear portion 5 at two meshing positions T having a positional relationship of 180°, the flexible gear portion 4 can be made into an elliptical shape as the simplest shape. Therefore, for example, the precision required when meshing at three or more meshing positions T can be suppressed to a minimum, the ease of manufacturing and processing can be improved, and durability, quietness and reliability can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a perspective view showing the entire basic form of a rotation reduction transmission device with a portion cut away for explaining the principle of the rotation reduction transmission device of the present invention.

[0034] Figure 2 It is a cross-sectional side view showing the entire rotation reduction transmission device.

[0035] Figure 3 This is an exploded perspective view of the main parts of the rotation reduction transmission device.

[0036] Figure 4 This is a front view including a partially extracted enlarged view showing the relationship between the flexible gear portion and the inner gear portion of the rotation reduction transmission device.

[0037] Figure 5 This is an explanatory diagram showing the operation of a part of the flexible spline portion of the rotation reduction transmission device.

[0038] Figure 6 This is a schematic cross-sectional structural diagram of the rotation reduction transmission device in a direction perpendicular to the axis, including an elliptical axis portion.

[0039] Figure 7This is a front view including a partially extracted enlarged view showing the relationship between the output plate portion and the transmission pin portion of the rotation reduction transmission device.

[0040] Figure 8 This is an axial cross-sectional view showing a part of the main portion of the rotation reduction transmission device.

[0041] Figure 9 This is an external view of an industrial robot using this rotation reduction transmission device.

[0042] Figure 10 It is an operation explanation diagram of the rotation reduction transmission device.

[0043] Figure 11 This is a front view of the output plate portion showing a state in which the transmission pin portion of the rotation reduction transmission device according to a preferred embodiment (first embodiment) of the present invention is engaged.

[0044] Figure 12 It is a cross-sectional side view of the output plate portion including a partially extracted enlarged view showing the engaged state of the transmission pin portion of the rotation reduction transmission device.

[0045] Figure 13 This is an explanatory diagram of the operation of the output plate portion showing a state in which the transmission pin portion of the rotation reduction transmission device is engaged.

[0046] Figure 14 It is a front view showing only a portion of the flexible spline portion of the rotation reduction transmission device extracted and illustrated.

[0047] Figure 15 This is a front view of an output plate portion showing a state in which a transmission pin portion of a rotation reduction transmission device according to another preferred embodiment (second embodiment) of the present invention is engaged.

[0048] Figure 16 This is an explanatory diagram of the operation of the output plate portion showing a state in which the transmission pin portion of the rotation reduction transmission device is engaged.

[0049] Figure 17 It is a cross-sectional side view of the output plate portion including a partially extracted enlarged view showing the engaged state of the transmission pin portion of the rotation reduction transmission device.

[0050] Label Description

[0051] 1: Rotational reduction transmission device, 2: Rotational input portion, 3: Elliptical shaft portion, 3c: Cam body portion, 3bi: Inner ring, 3bo: Outer ring, 3bm: Rotating element, 4: Flexible gear portion, 4g: External gear, 4p: Transmission pin portion, 4pm: Transmission pin body, 4pr: Transmission roller, 5: Inner gear portion, 5g: Internal gear, 6: Rotational output mechanism, 7: Output plate portion, 7s: Engaging portion, 7p: Elastic plate, 7sh: Engaging hole, 7sd: Elastic engaging portion, 7ss: One-way engaging hole, 7sm: Multi-directional engaging hole, 11: Input rotating element, 11i: Inner circumferential surface, 11o: Outer circumferential surface, Ff: Circumferential direction, Fd: Radial direction, Fs: Axial direction, T: Meshing position, Ls: Thickness, Ka: Cables, Kb: Cables, S: Wiring space DETAILED DESCRIPTION

[0052] Next, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0053] First, in order to facilitate understanding of the rotation reduction transmission device 1 of this preferred embodiment, refer to Figures 1 to 10 The structure and operation of the basic form of the rotation reduction transmission device 100 will be described.

[0054] This type of rotation reduction transmission device 100, 1 can be used for Figure 9 The joint mechanism Mj of the industrial robot R shown. The industrial robot R shown is a vertical multi-joint robot Rv, which has a robot body 22 set on the upper surface of the machine 21, and a robot controller 23. The robot controller 23 is housed in a base below the machine 21 to drive and control the robot body 22. The robot body 22 has a first arm (an arbitrary arm) 15 and a second arm (another arm) 16, and the first arm 15 and the second arm 16 are connected via a joint mechanism Mj. That is, a rotation reduction transmission device 100, 1 is built into the front end 15s of the first arm 15, and the rear end 16r of the second arm 16 is rotationally driven by the rotation reduction transmission device 100, 1. As a result, positioning control, angle control, speed control, etc. of the second arm 16 can be performed.

[0055] exist Figure 1 and Figure 2 The overall structure of the rotation reduction transmission device 100 is shown in FIG. Figure 2 In the figure, the imaginary lines are shown Figure 9 The front end portion 15s of the first arm 15 and the rear end portion 16r of the second arm 16 in the industrial robot R shown in FIG. Figure 1 and Figure 2As shown, the rotational speed reduction transmission device 100 comprises, generally from the upstream side in the rotation transmission direction, a rotation input portion 2, an elliptical shaft portion 3, a flexible gear portion 4, an inner gear portion 5, and a rotational output mechanism 6 (output plate portion 7). Thus, the rotational motion input to the rotational input portion 2 is reduced by a predetermined rate of 1 / 100 to 1 / 200, and the reduced rotational motion is output from the rotational output mechanism 6.

[0056] The structure of each part is described in detail below. The rotation input part 2 is composed of an input rotating body 11 formed into a cylindrical shape as a whole. The input rotating body 11 is supported by a bearing (ball bearing, etc.) 31 so as to be rotatable. In this case, the bearing 31 fixes the outer wheel on the support cylinder 32 and fixes the inner wheel on the outer peripheral surface of the input rotating body 11, wherein the support cylinder 32 is installed on the inner surface of the first arm 15. Figure 2 As shown, the inner portion of the inner circumferential surface 11i of the input rotor 11 serves as the routing space S for the cables Ka, Kb, etc. Therefore, the inner diameter and other parameters can be selected taking into account the size of the required routing space S. Furthermore, a cam body portion 3c is integrally formed at the middle portion of the outer circumferential surface 11o of the input rotor 11 in the axial direction Fs. This cam body portion 3c constitutes the elliptical shaft portion 3.

[0057] Therefore, using such a cylindrical input rotor 11 ensures sufficient routing space S for the cables Ka, Kb, etc., resulting in the following advantage: even when the number of cables Ka, Kb, etc. is large, the overall complexity of the system and other peripheral structures can be avoided. Reference numeral 33 denotes an input transmission device fixed to the end face of the input rotor 11.

[0058] like Figure 6 As shown, the elliptical shaft portion 3 has: a cam body portion 3c integrally formed on the input rotating body 11; an inner wheel 3bi provided along the outer peripheral surface of the cam body portion 3c; a flexible outer wheel 3bo; and a plurality of rotating bodies 3bm between the inner wheel 3bi and the outer wheel 3bo. The rotating body 3bm shown is a ball. In addition, the inner wheel 3bi can also serve as the outer peripheral surface of the cam body portion 3c. As a result, the cross-sectional shape of the inner peripheral surface 11i of the cam body portion 3c in the direction perpendicular to the axis becomes a circular shape, and the cross-sectional shape of the outer peripheral surface 11o of the cam body portion 3c in the direction perpendicular to the axis becomes an elliptical shape (refer to Figure 6 ).

[0059] On the other hand, a drive motor 34 such as a servo motor is fixed to the inner surface of the first arm portion 15, and a drive gear 34g mounted on the rotating shaft of the drive motor 34 is meshed with the input transmission device 33. As a result, the rotational motion from the drive motor 34 is input to the input rotating body 11 that is supported so as to rotate freely. In this way, if the rotational motion of the drive motor 34 is input to the rotation input portion 2 (input rotating body 11), the rotation reduction transmission device 100 can be constructed as a drive portion including the drive motor 34. Therefore, for example, there is the following advantage: it helps to miniaturize the drive portion built into the arm portion of the industrial robot, thereby improving durability and reliability. In addition, as a method of transmitting rotation from the drive motor 34 to the rotation input portion 2, a gear transmission mechanism is exemplified, but other rotation transmission methods such as a belt transmission mechanism using a synchronous belt and a pulley can also be used.

[0060] The flexible gear portion 4 is formed as a flexible endless belt by metal material (special steel, etc.). Figure 6 As shown, it is attached along the outer peripheral surface of the outer ring 3bo of the elliptical shaft portion 3. Figure 4 The overall shape of the flexible gear portion 4 is shown, and Figure 5 The diagram shows a partially enlarged view of the flexible gear portion 4. The flexible gear portion 4 has an external gear 4g formed on its outer peripheral surface along the circumferential direction Ff.

[0061] Furthermore, among each tooth portion (mountain portion) 4gs constituting the external gear 4g, a transmission pin body 4pm is buried (pressed into a hole) for every other tooth portion (mountain portion) 4gs. In this case, each tooth portion (mountain portion) 4gs has the function of supporting each transmission pin body 4pm, and therefore, a thickness and shape that can ensure the supporting strength are selected. In addition, an example is shown in which a transmission pin body 4pm is arranged on every other tooth portion (mountain portion) 4gs among each tooth portion (mountain portion) 4gs, but the interval between each transmission pin body 4pm can be set arbitrarily. Each transmission pin body 4pm uses a metal material having high rigidity and wear resistance, such as Figures 3 to 5 As shown, it is formed into a round rod with a circular cross section, as shown Figure 8 As shown, one end side is buried in each tooth portion (mountain portion) 4gs, and the other end side is extended from the side of the flexible gear portion 4 to the lateral side ( Figure 8 Thus, the transmission pin bodies 4pm are arranged at regular intervals along the circumferential direction Ff of the flexible gear portion 4.

[0062] Furthermore, the eccentric position of the transmission roller 4pr is rotatably mounted on the other end of each transmission pin body 4pm protruding from the lateral side of the flexible gear portion 4. Thus, the eccentric position of each transmission roller 4pr is supported by each transmission pin body 4pm so that it can rotate freely. Thus, the transmission pin portion 4p is formed by the transmission pin body 4pm protruding from the flexible gear portion 4 and the transmission roller 4pr supported in an eccentric position so that it can rotate freely about the transmission pin body 4pm as an axis. While the transmission pin portion 4p is preferably formed by the transmission pin body 4pm and the transmission roller 4pr, it is also possible to form an integrated transmission pin portion 4p having the shape of the transmission pin body 4pm without using the transmission roller 4pr.

[0063] On the other hand, on the inner peripheral surface of the flexible gear portion 4, at each position corresponding to the valley portion 4gd between each tooth portion (mountain portion) 4gs, as shown in FIG. Figure 5 As shown, the cutouts 4c are formed in a U-shape in the radial direction Fd. Thus, the thickness between each valley 4gd and each cutout 4c ensures flexibility (elasticity) that allows the elliptical shaft 3 to smoothly and stably follow the rotation. Figure 5 The solid line part shows Figure 4 The flexible gear portion 4 is shown in the shape when it is furthest away from the inner gear portion 5, and Figure 5 The imaginary line portion shows Figure 4 The shape shown is when the flexible gear portion 4 is closest to the inner gear portion 5 .

[0064] The inner gear portion 5 is formed as a whole into a rigid ring shape by metal material. Figure 3 As shown in FIG. 1 , an internal gear 5g is formed on the inner peripheral surface along the circumferential direction Ff. Figure 2 As shown, the outer circumferential surface of the inner gear portion 5 is attached to the inner surface of the first arm portion 15, and the external gear 4g of the flexible gear portion 4 is meshed with the internal gear 5g. At this time, the number of teeth per revolution of the internal gear 5g formed on the inner gear portion 5 is set to be greater than the number of teeth per revolution of the external gear 4g formed on the flexible gear portion 4. In the example shown, the number of teeth of the external gear 4g is set to "N", and the number of teeth of the internal gear 5g is set to "N+2".

[0065] In this case, the overall outer peripheral shape of the flexible gear portion 4 is an ellipse. Therefore, the flexible gear portion 4 meshes with the internal gear 5g at two meshing positions T that are 180 degrees apart. Thus, by meshing the flexible gear portion 4 with the internal gear 5g at two meshing positions T that are 180 degrees apart, the flexible gear portion 4 can be selected to have the simplest elliptical shape. This has the following advantages: For example, the precision required for meshing at three or more meshing positions T can be reduced, which improves manufacturing and processing ease, and contributes to improved durability, quietness, and reliability.

[0066] The rotary output mechanism 6 includes an annular output plate holder 12. The output plate holder 12 is supported on its inner circumference by a bearing (roller bearing) 36 disposed between the inner circumference and the outer circumference of the input rotary body 11, and on its outer circumference by a cross roller bearing 37 disposed between the outer circumference of the output plate holder 12 and the inner surface of the first arm portion 15. An annular recess 12h is formed on the end surface 12s of the output plate holder 12 that faces the flexible gear portion 4. The annular recess 12h is formed to engage with the output plate portion 7. Figure 2 The output plate portion 7 is fitted in. On the other hand, the output connecting plate 38 is fixed to the end surface 12t of the output plate holding body 12 on the opposite side to the end surface 12s having the annular recess 12h.

[0067] In addition, the output plate portion 7 is formed in a ring shape (ring plate shape), and a plurality of engaging holes 7sh that can be engaged with the transfer roller 4pr are formed. The engaging holes 7sh are formed at predetermined intervals along the circumferential direction Ff of the output plate portion 7, and are formed as slit-shaped long holes along the radial direction Fd so as to allow displacement of the transfer roller 4pr when the output plate portion 7 rotates. In addition, if the output plate portion 7 is formed in a ring shape, it is possible to ensure the wiring space for the cables Ka, Kb, etc., and, in particular, by combining with the input rotating body 11 formed in a cylindrical shape, there is an advantage in that it contributes to the simplification and high rigidity of the overall structure. In addition, in Figure 1 and Figure 2 In the drawing, reference numeral 40 denotes a sealing ring.

[0068] In this manner, when configuring the rotation output mechanism 6, using a transmission roller 4pr and an annular output plate portion 7 having a plurality of engagement holes 7sh provided in the radial direction Fd, displacement of the transmission pin portion 4p relative to the engagement holes 7sh occurring at various positions in the circumferential direction Ff can be effectively absorbed. The transmission roller 4pr is supported eccentrically about the transmission pin body 4pm as an axis. The plurality of engagement holes 7sh, which engage with the transmission roller 4pr and are formed at predetermined intervals along the circumferential direction Ff to accommodate displacement of the transmission roller 4pr during rotation transmission, can effectively absorb displacement of the transmission pin portion 4p relative to the engagement holes 7sh occurring at various positions in the circumferential direction Ff. Consequently, unnecessary stress generated when the engagement holes 7sh and the transmission pin body 4pm are directly engaged can be eliminated, enabling stable and smooth rotational transmission from the transmission pin portion 4p to the rotation output mechanism 6. Furthermore, unnecessary loss can be eliminated, further improving rotational transmission efficiency.

[0069] Therefore, according to such a basic form of the rotation reduction transmission device 100, it has: a rotation input part 2 that inputs rotational motion; a cam body part 3c that rotates integrally with the rotation input part 2, and an elliptical shaft part 3 that interposes a plurality of rotating bodies 3bm between an inner wheel 3bi and a flexible outer wheel 3bo provided along the outer periphery of the cam body part 3c; an inner gear part 5 that forms an inner gear 5g on the inner periphery and is fixed in position; a flexible gear part 4 that has an outer gear 4g and a transmission pin part 4p composed of a plurality of transmission pin bodies 4pm and a transmission roller 4pr, the outer gear 4g being formed along the circumferential direction Ff of the outer periphery and having a smaller number of teeth than the inner gear 5g, and when attached to the outer periphery of the elliptical shaft part 3, the outer gear 4g is fixed in position. g meshes with the internal gear 5g at two (generally speaking, multiple) meshing positions T on the circumferential direction Ff, and the multiple transmission pin bodies 4pm protrude from the side and are arranged at prescribed intervals along the circumferential direction Ff, and the transmission roller 4pr is supported in an eccentric position and can rotate freely about the transmission pin body 4pm as the axis; and a rotation output mechanism 6, which has an output plate portion 7 provided with a plurality of engaging holes 7sh in the radial direction Fd, and the plurality of engaging holes 7sh are for the transmission pin portion 4p to engage, and are arranged at prescribed intervals along the circumferential direction Ff, and allow displacement of the transmission pin portion 4p when rotation transmission is performed, so there is no need to use a thin-walled metal elastic plate to form the overall shape into a cup shape as in the past flexible spline.

[0070] As a result, manufacturing becomes easier, significantly reducing manufacturing costs. It also significantly reduces metal fatigue and malfunctions, improving durability and reliability, and significantly reducing both initial and operating costs. Furthermore, since the conventional flexspline is no longer required, the installation space in the axial direction Fs can be reduced, resulting in a thinner overall structure. This makes it possible to further miniaturize industrial robots, which previously faced limitations in miniaturization.

[0071] In addition, if the rotational reduction transmission device 100 is used to connect the joint mechanism Mj of any arm 15 and other arms 16 that constitute the robot R, it can help to reduce the thickness (miniaturization) of the joint mechanism Mj, and improve its durability and reliability. In particular, it has the advantage of being able to construct an optimal industrial robot (vertical multi-joint robot Rv, horizontal multi-joint robot, delta robot, etc.) for installation on a production line.

[0072] Next, refer to Figures 1 to 9 , mainly in accordance with Figure 10 The operation of the rotation reduction transmission device 100 having such a basic form is explained with reference to (a) to (d). Figure 10 (a) to (d) are principle diagrams, and therefore the elliptical shape of the cam body portion 3c is depicted in an exaggerated elongated shape.

[0073] First, when the robot controller 23 activates the drive motor 34, it operates, causing the drive gear 34g to rotate. This rotational motion is transmitted to the input transmission device 33 and, in turn, to the input rotating body 11, which includes the cam body 3c. This causes the cam body 3c to rotate at a relatively high speed.

[0074] Figure 10 (a) shows the state before the cam body 3c starts to rotate. In this state, the cam body 3c stops at the position Ps, and the longitudinal direction of the cam body 3c (the direction with the largest ellipse diameter) becomes the vertical direction. Therefore, the starting point of the flexible gear part 4 is located at the position marked Xs, which is consistent with the reference point Xo of the inner gear part 5. Figure 10 In the state (a), the external gear 4g of the flexible gear portion 4 meshes with the internal gear 5g of the inner gear portion 5 at two meshing positions T, one above the other.

[0075] Next, it is assumed that the cam body 3c is Figure 10 The position Ps in (a) is rotated 90° in the direction of arrow Dr. Figure 10 This state is shown in (b). In this case, the cam body 3c is displaced from the position Ps to the position P1 after rotating 90 degrees in the clockwise direction. As a result, the longitudinal direction of the cam body 3c becomes Figure 10(b) Therefore, as the cam body 3c rotates, the upper meshing position T (and similarly the lower meshing position T) where the external gear 4g and the internal gear 5g mesh with each other moves 90° clockwise. At this time, the number of teeth on the external gear 4g is N, and the number of teeth on the internal gear 5g is N+2. Therefore, the starting point of the flexible gear unit 4 is displaced by an angle Q1 = (360° / N) × 2) / 4 relative to the reference point Xo to position X1, which is the counterclockwise direction.

[0076] Furthermore, it is assumed that the cam body 3c is Figure 10 The position P1 in (b) is rotated 90° in the direction of the arrow Dr. Figure 10 (c) shows this state. In this case, the cam body 3c is displaced from position P1 to position P2 rotated 90° in the clockwise direction. Figure 10 As shown in (c), the longitudinal direction of the cam body 3c is the vertical direction. Therefore, the starting point of the flexible spline 4 is displaced to the position X2 in the counterclockwise direction relative to the reference point Xo by an angle Q2 = (360° / N) × 2) / 2.

[0077] Next, it is assumed that the cam body 3c is Figure 10 The state (c) is a state rotated 180° in the direction of arrow Dr. Figure 10 This state is shown in (d) of FIG. In this case, the cam body 3c is displaced from position P2 to position P3 after rotating 180 degrees. As a result, the longitudinal direction of the cam body 3c becomes the vertical direction, relative to Figure 10 The position (c) is reversed vertically. Therefore, the starting point of the flexible gear unit 4 is displaced to position X3, which is in the counterclockwise direction, by an angle Q3 (360° / N) × 2) relative to the reference point Xo. The cam body 3c then rotates once clockwise, and the flexible gear unit 4 decelerates by moving counterclockwise with the number of teeth "2."

[0078] The decelerated rotational motion of the flexible gear unit 4 is then transmitted to the rotation output mechanism 6. Specifically, the transmission pin 4p protruding from the flexible gear unit 4 includes a transmission roller 4pr supported in an eccentric position that engages with the engagement hole 7sh of the output plate unit 7. Therefore, the output plate unit 7 rotates in complete sync with the rotational motion of the flexible gear unit 4. In this case, the transmission pin 4p repeatedly displaces in the radial direction Dd along the trajectory of the outer circumferential surface of the cam body 3c, but this displacement is absorbed by the engagement hole 7sh formed by the elongated hole.

[0079] Moreover, if Figure 2As shown, the rotational motion of the output plate portion 7 is significantly decelerated relative to the input rotational motion and is then transmitted to the second arm portion 16 via the rotational output mechanism 6, which includes the output plate holder 12 and the output connecting plate 38, outside the output plate portion 7. This rotational displacement of the second arm portion 16 is achieved. In other words, the rotation is precisely controlled with the first arm portion 15 serving as a fulcrum.

[0080] Next, based on this basic form, refer to Figures 11 to 17 The rotation reduction transmission device 1 according to a preferred embodiment of the present invention will be described in detail. Figures 11 to 14 The first embodiment of the rotation reduction transmission device 1 is shown. Figures 15 to 17 A second embodiment of the rotation reduction transmission device 1 is shown.

[0081] [First embodiment]

[0082] First, refer to Figures 11 to 14 The rotation reduction transmission device 1 according to the first embodiment will be described.

[0083] The first embodiment is different in that the transmission pin portion 4p and the output plate portion 7 in the aforementioned basic form are modified. Figures 11 to 14 As shown, the first embodiment has a flexible gear portion 4, which has a plurality of transmission pin portions 4p protruding from the side and arranged at predetermined intervals along the circumferential direction Ff, and an output plate portion 7 provided with an engaging portion 7s, which is engaged with each transmission pin portion 4p and is arranged at predetermined intervals along the circumferential direction Ff, and allows displacement of the transmission pin portion 4p when rotation is transmitted. These basic structures are the same as the basic form, but differ in the following aspects.

[0084] First, while the basic form employs a structure in which the eccentric position of the transmission roller 4pr is supported by the transmission pin body 4pm, the first embodiment employs a structure in which the transmission pin 4p is configured by a transmission pin body 4pm protruding from the flexible gear portion 4 and a transmission roller 4pr supported in a central position for free rotation about the transmission pin body 4pm. This reduces contact friction between the transmission pin 4p and the engagement hole 7sh when the transmission pin 4p engages with the engagement hole 7sh. This allows for efficient and stable transmission of rotation from the flexible gear portion 4 to the output plate portion 7. Furthermore, wasteful heat generation and wear are eliminated, improving long-term reliability, similar to the basic form.

[0085] Second, when a plurality of engagement holes 7sh are provided at predetermined intervals along the circumferential direction Ff of the output plate portion 7 formed in the shape of an annular plate, in a basic form, the plurality of engagement holes 7sh are formed by slit-shaped elongated holes along the radial direction Fd so as to allow displacement of the transfer roller 4pr when the output plate portion 7 rotates. In the first embodiment, as shown in FIG. Figures 11 to 13 As shown, the multi-directional engagement hole 7sm is formed to always contact the peripheral surface of the transmission pin portion 4p (the peripheral surface of the transmission roller 4pr) and to allow displacement of the transmission pin portion 4p in the circumferential direction Ff and the radial direction Fd of the output plate portion 7.

[0086] Right now, Figure 13 As shown, each multi-directional engaging hole 7sm is formed along the circumferential direction Ff of the output plate portion 7 at intervals of Qs[°] (14.4[°] in the example). Therefore, for example, seven multi-directional engaging holes 7sm are formed within a range Zs of approximately 1 / 4 of the circumference. Figure 13 As shown, assuming that the upper end of the transmission roller 4pr abuts the uppermost end of the multi-directional engagement hole 7sm at the abutment position X1, which is the upper end of the inner surface of the multi-directional engagement hole 7sm, in the uppermost multi-directional engagement hole 7sm, and assuming that the output plate portion 7 rotates clockwise, the cam body 3c rotates by Qs[degrees], so that the abutment position X2 between the transmission roller 4pr and the multi-directional engagement hole 7sm is displaced by an angle of Qs[degrees] in the counterclockwise direction when viewed from the transmission roller 4pr. Similarly, when the cam body 3c rotates by Qs[°]×2, the contact position X3 between the transmission roller 4pr and the multi-directional engagement hole 7sm is displaced by Qs[°]×2 counterclockwise as viewed from the transmission roller 4pr. Furthermore, when the cam body 3c rotates by Qs[°]×3, the contact position X4 between the transmission roller 4pr and the multi-directional engagement hole 7sm is displaced by Qs[°]×3 counterclockwise as viewed from the transmission roller 4pr. Furthermore, when the cam body 3c rotates by Qs[°]×6, the contact position X7 between the transmission roller 4pr and the multi-directional engagement hole 7sm is displaced by Qs[°]×6 counterclockwise as viewed from the transmission roller 4pr, completing approximately 1 / 4 of a rotation. Furthermore, X5 and X6 indicate intermediate contact positions.

[0087] Therefore, the shape of the multi-directional engagement hole 7sm can be formed so that the outer circumferential surface of the transmission roller 4pr abuts the inner circumferential surface of the multi-directional engagement hole 7sm at any angular position within the 360° rotation of the cam body 3c, and in particular, the abutment can be maintained with the same pressure. Therefore, while high processing accuracy (shape accuracy) is required when forming the multi-directional engagement hole 7sm, it can be said that the cam method can absorb the displacement of the transmission pin portion 4p relative to the engagement hole 7sh in the circumferential direction Ff and radial directions Fd generated at different positions in the circumferential direction Ff. Therefore, unnecessary stress generated when the engagement hole 7sh and the transmission pin portion 4p are engaged can be eliminated, and stable and smooth rotation transmission from the transmission pin portion 4p to the output plate portion 7 is achieved. Furthermore, the advantage is that highly accurate rotation transmission can be achieved due to increased rigidity.

[0088] also, Figure 14 The flexible gear part 4 used in the first embodiment is shown as a modified example in which the following points are different from the basic form: each cutout part 4c is formed wider, and each transmission pin body 4pm is arranged between each cutout part 4c. Figures 11 to 14 In, with Figures 1 to 10 The same parts are denoted by the same reference numerals to clarify their structures, and detailed description thereof is omitted.

[0089] [Second embodiment]

[0090] Next, refer to Figures 15 to 17 A rotation reduction transmission device 1 according to a second embodiment will be described.

[0091] In the second embodiment, the output plate portion 7 of the first embodiment is changed, as shown in FIG. Figures 15 to 17 As shown, it has an output plate portion 7 provided with a locking portion 7s, and the locking portion 7s forms a locking hole 7sh, which is used for the locking of each transmission pin portion 4p and is arranged at predetermined intervals along the circumferential direction Ff. When the rotation is transmitted, the displacement of the transmission pin portion 4p is allowed. These basic structures are the same as those of the first embodiment, but are different in the following aspects.

[0092] That is, the output plate portion 7 of the second embodiment is constructed by an elastic engaging portion 7sd when forming the engaging portion 7s. The elastic engaging portion 7sd is capable of elastic displacement in the circumferential direction Ff by forming a one-way engaging hole 7ss. The one-way engaging hole 7ss is formed to protrude from the output plate portion 7 in the radial direction Fd, and is in constant contact with the circumferential surface of the transmission pin portion 4p, thereby allowing displacement of the transmission pin portion 4p in the radial direction Fd.

[0093] Therefore, when forming the output plate portion 7, as shown in FIG. Figure 17 As shown, a plurality of elastic plate members 7p having a predetermined thickness Ls are stacked in the axial direction Fs. Figure 17 (a) shows an example in which five elastic plates 7p are stacked. Figure 17 (b) shows a cross-section of an example in which three elastic plates 7p are stacked. In this manner, when constructing the output plate portion 7, by stacking multiple elastic plates 7p having a predetermined thickness Ls in the axial direction Fs, appropriate elasticity can be maintained even when the output plate portion 7 is relatively thick. This provides the advantage of enabling appropriate rotational transmission from the transmission pin portion 4p to the output plate portion 7 (rotational output mechanism 6).

[0094] Therefore, in the case of the second embodiment, it can be said that displacement of the transmission pin portion 4p relative to the engagement hole 7sh in the circumferential direction Ff, particularly in the circumferential direction Ff, occurring at different positions in the circumferential direction Ff can be elastically absorbed. Figure 16 The elastic engaging portion 7sd shown in the solid line is located at Figure 15 The uppermost elastic engaging portion 7sd, and Figure 16 The elastic engaging portion 7sd, indicated by the imaginary line, represents a position approximately one-quarter of a turn from the uppermost portion. Thus, displacement of the transmission pin portion 4p in the radial direction Fd is permitted by the guidance of the one-way engaging hole 7ss, while displacement of the transmission pin portion 4p in the circumferential direction Ff is permitted by the elastic displacement of the elastic engaging portion 7sd. Therefore, even in the structure of the second embodiment, unnecessary stress generated when the engaging hole 7sh and the transmission pin portion 4p engage, stable and smooth rotational transmission from the transmission pin portion 4p to the output plate portion 7 (rotational output mechanism 6) is achieved. Furthermore, since this structure is not dependent on machining accuracy, it offers the advantage of being easily and cost-effectively implemented.

[0095] In addition, in the second embodiment, the Figure 14 The flexible gear portion 4 shown. In addition, the structure of the transmission pin portion 4p in the second embodiment can also use the same structure as the first embodiment. Figures 11 to 14 In, with Figures 1 to 10 The same parts are assigned the same reference numerals to clarify their structures, and detailed description thereof is omitted.

[0096] Therefore, according to the rotation reduction transmission device 1 of this embodiment, in particular, as a basic structure, it has: a rotation input part 2 that inputs rotational motion; a cam body part 3c that rotates integrally with the rotation input part 2, and an elliptical shaft part 3 that interposes a plurality of rotating bodies 3bm between an inner wheel 3bi provided along the outer periphery of the cam body part 3c and a flexible outer wheel 3bo; an inner gear part 5 that forms an inner gear 5g on the inner periphery and is fixed in position; a flexible gear part 4 that has an outer gear 4g and a plurality of transmission pin parts 4p, the outer gear 4g being formed along the circumferential direction Ff of the outer periphery and having a smaller number of teeth than the inner gear 5g, and being attached to the elliptical shaft part 3 When the outer periphery of the gear 4g is engaged with the internal gear 5g at multiple meshing positions T on the circumferential direction Ff, the multiple transmission pin portions 4p protrude from the side and are arranged at specified intervals along the circumferential direction Ff; and a rotation output mechanism 6, the rotation output mechanism 6 has an output plate portion 7 with a locking portion 7s, the locking portion 7s forms a locking hole 7sh, the locking hole 7sh is for each transmission pin portion 4p to engage, and is arranged at specified intervals along the circumferential direction Ff, and allows displacement of the transmission pin portion 4p in the circumferential direction Ff and / or radial direction Fd when rotation transmission is performed, thereby being able to have the same effect as the basic form of the rotation reduction transmission device 100 mentioned above.

[0097] Specifically, the conventional flexspline, which uses a thin-walled metal elastic plate to form a cup-shaped overall shape, is no longer necessary. This makes manufacturing easier, significantly reducing manufacturing costs. Furthermore, metal fatigue and malfunctions are significantly reduced, leading to improved durability and reliability, significantly reducing both initial and operating costs. Furthermore, since the conventional flexspline is not required, the installation space in the axial direction Fs can be reduced. This allows for a thinner overall structure, enabling further miniaturization, particularly in industrial robots, where miniaturization has previously been limited.

[0098] The preferred embodiments (first embodiment and second embodiment) are described in detail above; however, the present invention is not limited to such embodiments, and the structure, shape, material, quantity, numerical value, etc. of the details can be changed, added, or deleted at will without departing from the scope of the present invention.

[0099] For example, the transmission pin portion 4p is shown as comprising a transmission pin body 4pm protruding from the flexible gear portion 4 and a transmission roller 4pr supported at a central position for free rotation about the transmission pin body 4pm. However, the transmission roller 4pr can be omitted and the shape of the transmission pin body 4pm can be selected to form an integrated transmission pin portion 4p. Furthermore, the output plate portion 7 is shown as being annular, and the rotation input portion 2 is formed by a cylindrical input rotating body 11. However, if there is no routing space S for the cables Ka, Kb, etc., an annular or cylindrical configuration is not necessary. Furthermore, the rotation input portion 2 is shown as having at least the cam body 3c of the elliptical shaft portion 3 integrally formed on the outer circumferential surface 11o. However, separate cam bodies 3c can also be attached using a predetermined mounting mechanism. Furthermore, the output plate portion 7 is shown as being formed by stacking multiple elastic sheet materials 7p having a predetermined thickness Ls in the axial direction Fs. However, a single-piece output plate portion 7 can also be used.

[0100] Meanwhile, the flexible gear portion 4 and the internal gear 5g of the inner gear portion 5 are shown as meshing at two meshing positions T at a 180° angle. However, the cam body 3c may also be shaped triangularly, squarely, or pentagonally, with meshing at three, four, or five meshing positions T. Furthermore, the rotation output mechanism 6 is shown as including an annular output plate holder 12 rotatably supported and having an annular recess 12h formed on its end surface 12s for retaining the output plate portion 7. However, this arrangement may be replaced with another structure that performs the same function. Furthermore, the transmission pins 4p are shown as being positioned correspondingly to the teeth (ridges) 4gs of the external gear 4g. However, this alignment is not essential, and the number and spacing of the transmission pins 4p need not necessarily match the number and spacing of the teeth (ridges) 4gs. On the other hand, while the example illustrates the rotational motion of the drive motor 34 as the input rotational motion, various other sources of rotational motion can be applied. Furthermore, while metal materials are illustrated as the materials forming each component, synthetic resin materials, fiber-reinforced composite materials, and components that do not require elasticity can also be made of ceramic materials. The type of material is not limited. Furthermore, the example illustrates the formation of U-shaped cutouts 4c in the radial direction Fd at various locations on the inner circumferential surface of the flexible gear portion 4 corresponding to the valleys 4gd between the teeth (mountains) 4gs. However, the shape and position (interval) of the cutouts 4c are arbitrary and do not necessarily need to be provided.

[0101] Industrial Application Possibilities

[0102] The rotation reduction transmission device of the present invention can be used as various rotation reduction transmission devices that require a function of reducing the speed of input rotational motion and outputting the reduced speed rotational motion, including a joint mechanism connecting an arm of an industrial robot.

Claims

1. A rotational speed reduction transmission device, which is provided in a joint mechanism and decelerates input rotational motion and outputs it, wherein the joint mechanism is connected to any arm of a robot and another arm, wherein the rotational speed reduction transmission device is characterized by: The rotation reduction transmission device has: a rotation input portion to which rotational motion is input, the rotation input portion having an inner square of an inner peripheral surface formed into a wiring space for cables and being composed of a cylindrical input rotating body; a cam body portion and an elliptical shaft portion, wherein the cam body portion is provided on the outer circumference of the input rotating body so as to rotate integrally with the rotation input portion, and the elliptical shaft portion is formed by interposing a plurality of rotating bodies between an inner wheel provided along the outer circumference of the cam body portion and a flexible outer wheel; an inner gear portion having an inner gear formed on its inner periphery and fixed in position; a flexible gear portion having an external gear formed along the circumference of the outer periphery and having fewer teeth than the internal gear, and meshing with the internal gear at two positions forming a 180° relationship in the circumferential direction when attached to the outer periphery of the elliptical shaft portion; a plurality of transmission pins, each comprising a transmission pin body protruding from a side surface of the flexible gear portion and a transmission roller supported at a center position so as to be rotatable about the transmission pin body, and arranged at predetermined intervals along the circumference of the flexible gear portion; and The rotation output mechanism comprises an annular output plate portion provided with an engaging portion, wherein the engaging portion is formed with engaging holes for engaging the transmission pin portions and is arranged at predetermined intervals along the circumferential direction to allow displacement of the transmission pin portions in the circumferential and / or radial directions during rotation transmission. The engaging portion is composed of a multi-directional engaging hole that is in constant contact with the peripheral surface of the transmission pin portion and allows displacement of the transmission pin portion in the circumferential direction and the radial direction of the output plate portion.

2. The rotation reduction transmission device according to claim 1, wherein: The inner peripheral surface of the flexible gear portion is formed with cutout portions for ensuring flexibility, and the transmission pin body is arranged between the cutout portions.

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