Transmission device and drive device

Abstract

The objective is to reduce the axial dimensions of a transmission device that receives rotation from a single drive source, reduces it in two reduction units, and outputs the result from two output units. [Solution] The transmission device includes one input shaft connected to a drive source, another input shaft directly connected to the first input shaft, one reduction unit including one output unit that reduces and outputs the rotation of one input shaft, and another reduction unit including another output unit that reduces and outputs the rotation of the other input shaft. The other output unit is arranged coaxially with the first output unit.

Description

Technical Field

[0001] The present disclosure relates to a transmission device and a driving device.

Background Art

[0002] Patent Document 1 discloses a transmission device including two reduction units. The two reduction units receive rotation input from one drive source. Each of the two reduction units includes an output unit. In the transmission device described in Patent Document 1, the rotation input from a single drive source is decelerated and output from the two output units. That is, rotation can be output at a desired rotational speed from the two output units while using only a single drive source (such as a motor). Further, the two reduction units are arranged coaxially. Therefore, according to the transmission device described in Patent Document 1, a space-saving design can be expected.

[0003] However, in the transmission device disclosed in Patent Document 1, one input shaft for inputting rotation to one reduction unit is indirectly connected via a differential device to another input shaft for inputting rotation to another reduction unit. The differential device is located between the two reduction units in the axial direction. Therefore, the dimensions of the transmission device disclosed in Patent Document 1 cannot be sufficiently miniaturized in the axial direction.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present disclosure has been made in consideration of the above points, and an object thereof is to reduce the axial dimension of a transmission device that decelerates rotation input from a single drive source by two reduction units and outputs the rotation from two output units.

Means for Solving the Problems

[0006] This disclosure is as follows: <1> ~ <12> Regarding.

[0007] <1> One input shaft connected to the drive source, One input shaft directly connected to the aforementioned one input shaft, A reduction unit including an output unit that reduces the rotation of one input shaft and outputs the result, A transmission device comprising: another reduction unit, which includes another output unit that reduces the rotation of the other input shaft and outputs the result, wherein the other output unit is arranged coaxially with the output unit.

[0008] <2> It comprises a connecting member located between one reduction unit and the other reduction unit in the axial direction, and connected to one output unit or the other output unit, <1> The transmission device described above.

[0009] <3> Between the one reduction unit and the other reduction unit in the axial direction, the one input shaft and the other input shaft are connected. <1> or <2> The transmission device described above.

[0010] <4> One of the input shafts and the other input shaft includes a cylindrical portion into which the other is inserted. <1> ~ <3> A transmission device as described in any one of the items.

[0011] <5> A connecting member located between one reduction gear and the other reduction gear in the axial direction, and connected to at least one of the one reduction gear and the other reduction gear, The system includes a bearing held by the connecting member and supporting one of the input shafts and the other input shaft, <1> ~ <4> The transmission device according to claim 1, as described in any one of the claims.

[0012] <6> The aforementioned input shaft includes teeth that mesh with the aforementioned reduction unit, The other input shaft includes teeth that mesh with the other reduction unit, The bearing supports one input shaft or the other input shaft at a position between the teeth of one input shaft and the teeth of the other input shaft in the axial direction. <5> The transmission device described above.

[0013] <7> One of the input shafts and the other input shaft includes a cylindrical portion into which the other is inserted. The bearing supports the cylindrical portion, <5> or <6> The transmission device described above.

[0014] <8> The aforementioned reduction unit includes a case and a carrier that is rotatable relative to the case, The aforementioned output unit is composed of either the case or the carrier of the aforementioned reduction unit. The other reduction gear includes a case and a carrier that is rotatable relative to the case, The other output unit is comprised of either the case or the carrier of the other reduction unit. The device includes a connecting member that connects the case of one reduction unit to the case of the other reduction unit, or connects the carrier of one reduction unit to the carrier of the other reduction unit. <1> ~ <7> A transmission device as described in any one of the items.

[0015] <9> The aforementioned reduction unit includes a case and a carrier that is rotatable relative to the case, The aforementioned output unit is composed of either the case or the carrier of the aforementioned reduction unit. The other reduction gear includes a case and a carrier that is rotatable relative to the case, The other output unit is comprised of either the case or the carrier of the other reduction unit. A transmission device according to any one of <1> to <8>, comprising a connecting member that connects the case of the one reduction unit to the carrier of the other reduction unit, or connects the carrier of the one reduction unit to the case of the other reduction unit.

[0016] <10> A transmission device according to any one of <1> to <9>, wherein the reduction ratio of the one reduction unit is different from the reduction ratio of the other reduction unit.

[0017] <11> The reduction unit includes a case including internal teeth, a carrier rotatable relative to the case, a shaft member rotatably supported by the carrier, an external gear including external teeth supported by the shaft member and eccentrically oscillating in conjunction with the rotation of the shaft member to mesh with the internal teeth, and a transmission device according to any one of <1> to <10>.

[0018] <12> A transmission device according to any one of <1> to <11>, and a drive source including a drive shaft directly connected to the one input shaft.

Advantages of the Invention

[0019] According to the present disclosure, in a transmission device that decelerates the rotation input from a single drive source by two reduction units and outputs it from two output units, the axial dimension can be reduced.

Brief Description of the Drawings

[0020] [Figure 1] FIG. 1 is a diagram for explaining an embodiment, and is a longitudinal sectional view showing a specific example of a transmission device. [Figure 2] FIG. 2 is a longitudinal sectional view showing another specific example of the transmission device. [Figure 3] FIG. 3 is a longitudinal sectional view showing still another specific example of the transmission device. [Figure 4] Figure 4 is a longitudinal cross-sectional view showing yet another specific example of a transmission device. [Figure 5] Figure 5 is a cross-sectional view showing an example of a reduction gear included in the transmission device shown in Figures 1 to 4. [Figure 6] Figure 6 is a cross-sectional view along the line VI-VI in Figure 5. [Figure 7] Figure 7 is a schematic front view showing the drive unit and transmission unit. [Modes for carrying out the invention]

[0021] This embodiment will be described below with reference to specific examples shown in the drawings. Figures 1 to 7 are diagrams illustrating this embodiment. Some configurations shown in some figures may be omitted in others. The scale and aspect ratios may differ between the drawings.

[0022] As schematically shown in Figure 7, the drive unit 5 includes a drive source 6 and a transmission unit 10. The drive source 6 inputs rotation to the transmission unit 10. The transmission unit 10 includes a first input shaft 20, a second input shaft 30, a first reduction unit (first speed reducer) 25, and a second reduction unit (second speed reducer) 35. The first input shaft 20 is connected to the drive source 6. The second input shaft 30 is connected to the first input shaft 20.

[0023] The first reduction unit 25 receives rotation input from the first input shaft 20. The first reduction unit 25 reduces the rotation from the first input shaft 20 and outputs it. The first reduction unit 25 includes a first output unit 26 that outputs rotation.

[0024] The second reduction unit 35 receives rotation input from the second input shaft 30. The second reduction unit 35 reduces the rotation from the second input shaft 30 and outputs it. The second reduction unit 35 includes a second output unit 36 ​​that outputs rotation.

[0025] The drive unit 5 and transmission unit 10 according to this embodiment reduce the rotation input from a single drive source 6 by first and second reduction units 25 and 35, and output it from first and second output units 26 and 36. This drive unit 5 and transmission unit 10 can be applied to an industrial robot, for example. As shown in Figure 7, the first output unit 26 may hold a first held member 26X. The first held member 26X is driven by the first output unit 26. The second output unit 36 ​​may hold a second held member 36X. The second held member 36X is driven by the second output unit 36. The first held member 26X and the second held member 36X are not particularly limited. For example, the first held member 26X and the second held member 36X may be a workpiece, a workpiece tool, or a processing tool.

[0026] In this embodiment, measures have been taken to reduce the axial dimensions of the transmission device 10, which reduces the rotation input from a single drive source 6 by two reduction units 25 and 35 and outputs the rotation from two output units 26 and 36. The drive device 5 and the transmission device 10 will be described in more detail below with reference to the drawings that show a more specific configuration.

[0027] The first input axis 20 is also referred to as "one input axis." The first input axis 20 may correspond to one input axis in the claim. The second input axis 30 is also referred to as "another input axis." The second input axis 30 may correspond to another input axis in the claim.

[0028] The first deceleration unit 25 is also called "one deceleration unit." The first deceleration unit 25 may correspond to one deceleration unit in the claim. The second deceleration unit 35 is also called "another deceleration unit." The second deceleration unit 35 may correspond to another deceleration unit in the claim.

[0029] The first output unit 26 is also called "one output unit." The first output unit 26 may correspond to one output unit in the claim. The second output unit 36 ​​is also called "another output unit." The second output unit 36 ​​may correspond to another output unit in the claim.

[0030] Figure 1 shows a specific example of the drive unit 5 and the transmission unit 10. As described above, the transmission unit 10 includes a first input shaft 20, a second input shaft 30, a first reduction unit 25, and a second reduction unit 35. The drive unit 5 includes a drive source 6 that inputs rotation to the transmission unit 10.

[0031] The drive source 6 is not particularly limited. For example, the drive source 6 may be a motor. The motor is not particularly limited. The motor may be a servo motor. The motor may be a brushless motor. The drive source 6 may include a drive source body 7 and a drive shaft 8, as shown in Figure 1. The drive shaft 8 is rotatably held relative to the drive source body 7. In the illustrated example, the drive shaft 8 is an elongated shaft-shaped member. The drive shaft 8 is rotatable about its central axis. The drive source 6 outputs the rotation of the drive shaft 8. The rotation of the drive shaft 8 is input to the transmission device 10.

[0032] The first input shaft 20 is connected to the drive source 6. The first input shaft 20 is connected to the drive shaft 8. As shown in the figure, the first input shaft 20 may be directly connected to the drive shaft 8. The first input shaft 20 is connected to the drive shaft 8 in such a way that it cannot rotate relative to the drive shaft 8 about the drive shaft 8's axis of rotation. By being fixed to the drive shaft 8, the first input shaft 20 rotates in sync with the drive shaft 8. That is, the first input shaft 20 rotates in the same direction and at the same rotational speed as the drive shaft 8. In the illustrated example, the first input shaft 20 is an elongated shaft-shaped member. The first input shaft 20 is rotatable about its central axis.

[0033] The second input shaft 30 is connected to the first input shaft 20. In this embodiment, the second input shaft 30 may be directly connected to the first input shaft 20. The second input shaft 30 is connected to the first input shaft 20 in such a way that it cannot rotate relative to the first input shaft 20 with respect to the first input shaft 20's axis of rotation. By being fixed to the first input shaft 20, the second input shaft 30 rotates in sync with the first input shaft 20. That is, the second input shaft 30 rotates in the same direction and at the same rotational speed as the first input shaft 20. In the illustrated example, the second input shaft 30 is an elongated shaft-shaped member. The second input shaft 30 is rotatable about its central axis. In the illustrated example, the central axis of the first input shaft 20 and the central axis of the second input shaft 30 are located on the same straight line.

[0034] The first input shaft 20 and the second input shaft 30 may be connected between the first reduction unit 25 and the second reduction unit 35 in the axial direction D1. In the example shown in Figure 1, the entire length of the connection between the first input shaft 20 and the second input shaft 30 is located between the first reduction unit 25 and the second reduction unit 35 in the axial direction D1. However, unlike the illustrated example, at least a portion of the connection between the first input shaft 20 and the second input shaft 30 may be located between the first reduction unit 25 and the second reduction unit 35 in the axial direction D1. Even when at least a portion of the connection is located between the first reduction unit 25 and the second reduction unit 35 in the axial direction D1, the first input shaft 20 and the second input shaft 30 are still described as being connected between the first reduction unit 25 and the second reduction unit 35 in the axial direction D1.

[0035] The connection between the first input shaft 20 and the second input shaft 30 is not particularly limited. The first input shaft 20 and the second input shaft 30 may be connected using various methods and various components. The first input shaft 20 and the second input shaft 30 may be connected by press-fitting. The first input shaft 20 and the second input shaft 30 may be connected using a coupling or other connecting device 16 (see Figures 3 and 4, which will be mentioned later). The first input shaft 20 and the second input shaft 30 may be spline-connected. The first input shaft 20 and the second input shaft 30 may be joined using an adhesive or other bonding agent. The first input shaft 20 and the second input shaft 30 may be welded together by ultrasonic bonding or welding.

[0036] As shown in Figure 1, one of the first input shaft 20 and the second input shaft 30 may include a cylindrical portion 18 into which the other is inserted. By using the cylindrical portion 18 for connection, the connection portion of the first input shaft 20 and the second input shaft 30 can be made longer in the axial direction D1, allowing the first input shaft 20 and the second input shaft 30 to be stably and firmly connected. At the same time, it is possible to avoid the total length of the first input shaft 20 and the second input shaft 30 along the axial direction D1 becoming excessive.

[0037] Furthermore, by adopting a connecting configuration that includes the cylindrical portion 18, the outer diameters of the first input shaft 20 and the second input shaft 30 can be made different. As a result, the number of teeth of the first input teeth 21 provided on the first input shaft 20 and the number of teeth of the second input teeth 31 provided on the second input shaft 30 can be set with a high degree of freedom. This makes it possible to adjust the output from the first output unit 26 and the output from the second output unit 36 ​​to a desired rotational speed.

[0038] The first input tooth 21 is a tooth that meshes with the first reduction unit 25. In the illustrated example, the first input tooth 21 is configured as an external tooth. By meshing the first input tooth 21 with the first reduction unit 25, the rotation of the first input shaft 20 is transmitted to the first reduction unit 25. Similarly, the second input tooth 31 is a tooth that meshes with the second reduction unit 35. In the illustrated example, the second input tooth 31 is configured as an external tooth. By meshing the second input tooth 31 with the second reduction unit 35, the rotation of the second input shaft 30 is transmitted to the second reduction unit 35.

[0039] Furthermore, teeth may be provided on a portion of the outer surface of the cylindrical portion 18 along the axial direction D1, and the remaining portion of the outer surface of the cylindrical portion 18 may be used as the cylindrical outer circumferential surface 18a. The cylindrical outer circumferential surface 18a functions as the surface supported by the bearing 17.

[0040] As shown in Figure 1, the bearing 17 may support the first input shaft 20 or the second input shaft 30 at a position between the first input teeth 21 and the second input teeth 31 in the axial direction D1. In the illustrated example, the cylindrical outer surface 18a is located between the first input teeth 21 and the second input teeth 31 in the axial direction D1. With this configuration, the first input shaft 20 or the second input shaft 30 can be supported by the bearing 17 near the meshing portion between the first input shaft 20 and the first reduction gear 25 by the first input teeth 21. At the same time, the first input shaft 20 or the second input shaft 30 can be supported by the bearing 17 near the meshing portion between the second input shaft 30 and the second reduction gear 35 by the second input teeth 31. Therefore, the bearing 17 can stably support the first input shaft 20 and the second input shaft 30.

[0041] In the example shown in Figure 1, the second input shaft 30 includes a cylindrical portion 18. The first input shaft 20 is inserted into the cylindrical portion 18 constituting the second input shaft 30 at one end in the axial direction D1. The outer surface of the first input shaft 20 is spline-coupled to the inner surface of the cylindrical portion 18.

[0042] As described above, the first reduction unit 25 includes a first output unit 26. The first reduction unit 25 reduces the rotation transmitted from the first input shaft 20 and outputs it from the first output unit 26. Similarly, the second reduction unit 35 includes a second output unit 36. The second reduction unit 35 reduces the rotation transmitted from the second input shaft 30 and outputs it from the second output unit 36.

[0043] The second output unit 36 ​​is arranged coaxially with the first output unit 26. Coaxial means that the rotation axis of the second output unit 36 ​​is aligned with the rotation axis of the first output unit 26. The rotation axis of the first output unit 26 and the rotation axis of the second output unit 36 ​​are collectively referred to as the main rotation axis MRA, using the symbol RA. The axial direction D1 is parallel to the main rotation axis MRA. The radial direction D2 is perpendicular to the main rotation axis MRA. The circumferential direction D3 is along the circumference of the circle centered on the main rotation axis MRA. The inner side in the radial direction D2 means the side closer to the main rotation axis MRA in the radial direction D2. The outer side in the radial direction D2 means the side further away from the main rotation axis MRA in the radial direction D2.

[0044] In the illustrated example, the first input shaft 20 is arranged coaxially with the second input shaft 30. The first input shaft 20 is arranged coaxially with the first reduction unit 25. The second input shaft 30 is arranged coaxially with the second reduction unit 35.

[0045] As shown in Figure 1, the first reduction unit 25 may include a first case 40A and a first carrier 50A that is rotatable relative to the first case 40A. The first output unit 26 is composed of the first case 40A or the first carrier 50A. Similarly, the second reduction unit 35 may include a second case 40B and a second carrier 50B that is rotatable relative to the second case 40B. The second output unit 36 ​​is composed of the second case 40B or the second carrier 50B.

[0046] The first reduction unit 25 and the second reduction unit 35 are not particularly limited. The first reduction unit 25 and the second reduction unit 35 can employ various configurations and mechanisms capable of reducing and transmitting rotation.

[0047] Here, with reference to Figures 5 and 6, a specific example of the reduction units 25 and 35 will be described. The description of "reduction units 25 and 35" using the symbols "25" and "35" applies to both the first reduction unit 25 and the second reduction unit 35. The description of "case 40" using the symbol "40" applies to both the first case 40A and the second case 40B. The description of "carrier 50" using the symbol "50" applies to both the first carrier 50A and the second carrier 50B.

[0048] The reduction gears 25 and 35 shown in Figures 5 and 6 further include a shaft member 70 and an external gear 60, in addition to the case 40 and carrier 50. The shaft member 70 is rotatably supported by the carrier 50. The external gear 60 passes through the shaft member 70. The external gear 60 is supported on the shaft member 70. The external gear 60 oscillates eccentrically as the shaft member 70 rotates. The case 40 includes internal teeth 45. The external gear 60 includes external teeth 65. The external teeth 65 of the eccentrically oscillating external gear 60 mesh with the internal teeth 45 of the case 40, and the carrier 50 supporting the external gear 60 via the shaft member 70 and the case 40 rotate relative to each other. When the carrier 50 is fixed and stationary, the case 40 rotates as output units 26 and 36. When the case 40 is fixed and stationary, the carrier 50 rotates as output units 26 and 36.

[0049] The following will detail the specific configurations of case 40, carrier 50, external gear 60, and shaft member 70 as shown in the illustration.

[0050] The internal teeth 45 of case 40 are arranged in the circumferential direction D3. In the illustrated example, the reduction gears 25 and 35 have two external gears 60A and 60B arranged in the axial direction D1. Each internal tooth 45 extends in the axial direction D1 and meshes with the external teeth 65 of the two external gears 60A and 60B.

[0051] The illustrated case 40 includes a substantially cylindrical case body 41 and internal tooth pins 44 held on the inner surface of the case body 41. The case body 41 has a plurality of pin grooves formed therein, which are arranged in the circumferential direction D3. The pin grooves extend in the axial direction D1 and house and hold the cylindrical internal tooth pins 44. Each internal tooth pin 44 constitutes one internal tooth 45.

[0052] The carrier 50 is held within the case 40 via a pair of main bearings 47. The carrier 50 is rotatable relative to the case 40 about the main rotation axis MRA. The illustrated carrier 50 has a carrier base 51 and a carrier plate 52 fixed to each other. The carrier base 51 and the carrier plate 52 are fixed to each other using fasteners such as bolts. The carrier base 51 includes a disc-shaped base plate portion 51a and a plurality of column portions 51b projecting from the base plate portion 51a in the axial direction D1. The base plate portion 51a and the plurality of column portions 51b may be formed integrally.

[0053] Multiple columnar sections 51b may be provided at equal intervals in the circumferential direction D3 centered on the main rotation axis MRA. In the illustrated example, three columnar sections 51b are provided. The number of columnar sections 51b can be varied in various ways, and the example is not limited to the illustrated example. For example, two or four columnar sections 51b may be provided.

[0054] The illustrated carrier 50 is provided with a central hole 54 and through holes 55. The central hole 54 and through holes 55 penetrate the carrier base 51 and the carrier plate 52, respectively. The central hole 54 is located on the main rotation axis MRA. The carrier 50 is provided with multiple through holes 55. The multiple through holes 55 are located at equal intervals in the circumferential direction D3 around the main rotation axis MRA.

[0055] The shaft member 70 is rotatably held by the carrier 50. The illustrated shaft member 70 is inserted into a through hole 55 of the carrier 50. A pair of bearings 48 are provided between the carrier 50 and the shaft member 70. The bearings 48 may be tapered roller bearings. Through the bearings 48, the shaft member 70 is rotatable relative to the carrier 50 about the axis of rotation RA. The axis of rotation RA is parallel to the axial direction D1.

[0056] The illustrated reduction gears 25 and 35 include multiple shaft members 70, each inserted into a plurality of through holes 55. The multiple shaft members 70 are positioned at equal intervals in the circumferential direction D3 around the rotation axis MRA. In the illustrated specific example, three through holes 55 are provided. In the illustrated example, three shaft members 70 are provided. The number of shaft members 70 and through holes 55 can be varied in various ways, and the illustration is not limited to the illustrated example. For example, two shaft members 70 and two through holes 55 may be provided, or four shaft members 70 and four through holes 55 may be provided.

[0057] The illustrated shaft member 70 includes a shaft body portion 71 and a pair of eccentric bodies 75 located on the shaft body portion 71. The eccentric bodies 75 are cylindrical portions. The eccentric bodies 75 expand in diameter from the shaft body portion 71. The eccentric bodies 75 are eccentric from the rotation axis RA, which is the rotation center of the shaft member 70. The pair of eccentric bodies 75 includes a first eccentric body 75A and a second eccentric body 75B. The first eccentric body 75A and the second eccentric body 75B are eccentric by the same amount in the opposite direction from the rotation axis RA. In other words, in a cross section perpendicular to the axial direction D1, the centers of the first eccentric body 75A and the second eccentric body 75B are point-symmetric with respect to a point on the rotation axis RA.

[0058] The shaft body portion 71 has a first bearing support portion 72a which is inserted into the carrier base 51, and a second bearing support portion 52b which is inserted into the carrier plate 52. The bearing support portions 72a and 72b each support a bearing 48. A pair of eccentric bodies 75A and 75B are located between the pair of bearing support portions 72a and 72b in the axial direction D1. The illustrated shaft member 70 further includes an input gear 79 fixed to the shaft body portion 71. As shown in Figure 1, the input gear 79 meshes with the teeth 21 and 31 of the input shafts 20 and 30. In the illustrated example, the input gear 79, the first bearing support portion 72a, the first eccentric body 75A, the second eccentric body 75B, and the second bearing support portion 52b are located in this order in the axial direction D1.

[0059] The illustrated reduction gears 25 and 35 have an external gear 60, which is a first external gear 60A and a second external gear 60B. The first external gear 60A is located on a first eccentric body 75A of a plurality of shaft members 70. The second external gear 60B is located on a second eccentric body 75B of a plurality of shaft members 70. The first external gear 60A and the second external gear 60B are located in the axial direction D1 between the base plate portion 51a and the carrier plate 52 of the carrier base 51.

[0060] The illustrated external gear 60 includes a disc-shaped central plate portion 61 and external teeth 65 arranged on the periphery of the central plate portion 61. The central plate portion 61 is provided with a central hole 62a and column-through holes 62b. The central hole 62a is located on the main rotation axis MRA. The central hole 62a faces the central hole 54 in the axial direction D1. In the illustrated example, multiple column-through holes 62b are located at equal intervals in the circumferential direction D3 centered on the central hole 62a. The column portion 51b of the carrier 50 passes through the column-through holes 62b. The number of column-through holes 62b may be the same as the number of column portions 51b.

[0061] The central plate portion 61 is further provided with shaft through holes 63. In the illustrated example, multiple shaft through holes 63 are positioned at equal intervals in the circumferential direction D3 centered on the central hole 62a. An eccentric body 75 is placed inside the shaft through holes 63. A bearing 49 is provided between the eccentric body 75 and the external gear 60. The bearing 49 may be a cylindrical roller bearing. The first external gear 60A is supported on the first eccentric body 75A of the shaft member 70 via the bearing 49. The second external gear 60B is supported on the second eccentric body 75B of the shaft member 70 via the bearing 49. The number of shaft through holes 63 may be the same as the number of shaft members 70.

[0062] Each external gear 60 is supported by a plurality of eccentric bodies 75. The eccentric bodies 75 included in the plurality of shaft members 70 are aligned in phase. Therefore, as the plurality of shaft members 70 rotate, the external gear 60 eccentrically oscillates. In other words, as the plurality of shaft members 70 rotate, the external gear 60 translates along a circumferential path centered on the main rotation axis MRA. The first external gear 60A and the second external gear 60B operate with a half-phase difference.

[0063] Rotation is input from the reduction units 25 and 35, which have the above configuration. The teeth 21 and 31 of the input shafts 20 and 30, which are arranged on the main rotation axis MRA, mesh with the input gears 79 of the multiple shaft members 70. When the output gear rotates, the shaft members 70 rotate together with the input gears 79, causing the external gear 60 to oscillate eccentrically. At this time, the external teeth 65 of the external gear 60 mesh with the internal teeth 45 of the case 40. Due to the difference in the number of teeth between the external teeth 65 and the internal teeth 45, the carrier 50 that supports the external gear 60 via the shaft members 70 and the case 40 rotate relative to each other about the main rotation axis MRA. If the case 40 is fixed, the rotation of the carrier 50 is output. If the carrier 50 is fixed, the rotation of the case 40 is output.

[0064] The reduction gears 25 and 35 shown in Figures 5 and 6 are of the eccentric oscillating type. The reduction gears 25 and 35 are not limited to the illustrated examples and may be of the planetary gear type. The planetary gear type reduction gears 25 and 35 include a carrier 50 that rotatably supports the planetary gears and a case 50 having internal teeth that mesh with the planetary gears. In the planetary gear type reduction gears 25 and 35, rotation is transmitted from the input shafts 20 and 30 that constitute the sun gear to the planetary gears.

[0065] As shown in Figure 1, the transmission device 10 may further include a connecting member 15. The connecting member 15 is located between the first reduction section 25 and the second reduction section 35 in the axial direction D1. "Located between the first reduction section 25 and the second reduction section 35 in the axial direction D1" means not only that the entire connecting member 15 is located between the first reduction section 25 and the second reduction section 35 in the axial direction D1, but also that at least a portion of the connecting member 15 is located between the first reduction section 25 and the second reduction section 35 in the axial direction D1.

[0066] The first reduction unit 25 and the second reduction unit 35 are arranged coaxially. The first reduction unit 25 and the second reduction unit 35 each include output units 26 and 36, respectively. Therefore, some gap may be created between the first reduction unit 25 and the second reduction unit 35. This gap can be used to arrange the connecting member 15 while suppressing an increase in the axial dimension D1 of the transmission device 10.

[0067] The connecting member 15 may be connected to the first output unit 26 or the second output unit 36. In this configuration, the connecting member 15 operates together with the first output unit 26 or the second output unit 36. The connecting member 15 connected to the first output unit 26 may hold the first retained member 26X in place of the first output unit 26. The connecting member 15 connected to the second output unit 36 ​​may hold the second retained member 36X in place of the second output unit 36. The connecting member 15 may also function as an extension of the output units 26 and 36. With this configuration, the retained members 26X and 36X can be held in the appropriate position and orientation.

[0068] In the example shown in Figure 1, the connecting member 15 is connected to the first case 40A, which is the first output unit 26 of the first reduction unit 25. However, the example is not limited to the one shown in Figure 1, and the connecting member 15 may also be connected to the second output unit 36 ​​of the second reduction unit 35.

[0069] The connecting member 15 may be connected to at least one of the first reduction gear 25 and the second reduction gear 35 and may hold the bearing 17. In the illustrated example, the connecting member 15 includes an inner flange portion 15a (see Figure 1) that protrudes inward in the radial direction D2. The inner flange portion 15a is located between the two reduction gears 25 and 35 in the axial direction D1. The bearing 17 is held by the inner flange portion 15a.

[0070] The bearing 17 may support at least one of the first input shaft 20 and the second input shaft 30. In this configuration, at least one of the first input shaft 20 and the second input shaft 30 is rotatably supported by a bearing 17 held by a connecting member 15 connected to at least one of the first reduction unit 25 and the second reduction unit 35. The first input shaft 20 and the second input shaft 30 are stably supported by the bearing 17, and their relative positions with respect to the first reduction unit 25 and the second reduction unit 35 can be stably maintained.

[0071] In the example shown in Figure 1, the connecting member 15 is connected to both the first reduction unit 25 and the second reduction unit 35. However, the example is not limited to the one shown in Figure 1, and the connecting member 15 may be connected only to the first reduction unit 25, or only to the second reduction unit 35.

[0072] In the example shown in Figure 1, the connecting member 15 supports the second input shaft 30. However, the example is not limited to that shown in Figure 1, and the connecting member 15 may also support the first input shaft 20.

[0073] As described above, the first reduction unit 25 includes a first case 40A and a first carrier 50A that are rotatable relative to each other about the main rotation axis MRA. The first output unit 26 is composed of one of the first case 40A and the first carrier 50A. The other of the first case 40A and the first carrier 50A that does not constitute the first output unit 26 has its rotation fixed. The other of the first case 40A and the first carrier 50A that does not constitute the first output unit 26 may be fixed to the drive source body 7 of the drive source 6, or it may be fixed to the mounting base to which the transmission device 10 is fixed.

[0074] The second reduction gear section 35 includes a second case 40B and a second carrier 50B that are rotatable relative to each other about the main rotation axis MRA. The second output section 36 is composed of one of the second case 40B and the second carrier 50B. The other part of the second case 40B and the second carrier 50B that does not constitute the second output section 36 is fixed in place. The other part of the second case 40B and the second carrier 50B that does not constitute the second output section 36 may be fixed to the drive source body 7 of the drive source 6, or to the mounting base to which the transmission device 10 is fixed.

[0075] In this example, the transmission device 10 may include a connecting member 15 that connects the first case 40A and the second case 40B. The transmission device 10 may also include a connecting member 15 that connects the first carrier 50A and the second carrier 50B.

[0076] The connecting member 15 that connects a pair of cases 40A, 40B, or a pair of carriers 50A, 50B, may be connected to the first output unit 26 of the first reduction unit 25. In this example, the second output unit 36 ​​of the second reduction unit 35 is composed of the second case 40B and the second carrier 50B that are not connected to the connecting member 15. That is, one of the second case 40B and the second carrier 50B may be connected to the first reduction unit 25 by the connecting member 15, and the other of the second case 40B and the second carrier 50B may constitute the second output unit 36.

[0077] The connecting member 15 that connects a pair of cases 40A, 40B, or a pair of carriers 50A, 50B, may be connected to the second output section 36 of the second reduction unit 35. In this example, the first output section 26 of the first reduction unit 25 is composed of the part of the first case 40A and the first carrier 50A that is not connected to the connecting member 15. That is, one of the first case 40A and the first carrier 50A may be connected to the second reduction unit 35 by the connecting member 15, and the other of the first case 40A and the first carrier 50A may constitute the first output section 26.

[0078] The connecting member 15 that connects a pair of cases 40A, 40B, or a pair of carriers 50A, 50B, does not need to be connected to the first output unit 26, nor does it need to be connected to the second output unit 36. In this example, the first output unit 26 of the first reduction unit 25 is made up of the first case 40A and the first carrier 50A that is not connected to the connecting member 15. In this example, the second output unit 36 ​​of the second reduction unit 35 is made up of the second case 40B and the second carrier 50B that is not connected to the connecting member 15. In other words, one of the first case 40A and the first carrier 50A may be connected to the second reduction unit 35 by a connecting member 15, and the other of the first case 40A and the first carrier 50A may constitute the first output unit 26, and one of the second case 40B and the second carrier 50B may be connected to the first reduction unit 25 by a connecting member 15, and the other of the second case 40B and the second carrier 50B may constitute the second output unit 36.

[0079] The transmission device 10 may include a connecting member 15 that connects the first case 40A and the second carrier 50B.

[0080] The first case 40A and the second carrier 50B, or the connecting member 15 connecting the first carrier 50A and the second case 40B, may be connected to the first output unit 26 of the first reduction unit 25. In this example, the second output unit 36 ​​of the second reduction unit 35 is composed of the part of the second case 40B and the second carrier 50B that is not connected to the connecting member 15. That is, one of the second case 40B and the second carrier 50B may be connected to the first reduction unit 25 by the connecting member 15, and the other of the second case 40B and the second carrier 50B may constitute the second output unit 36.

[0081] The first case 40A and the second carrier 50B, or the connecting member 15 connecting the first carrier 50A and the second case 40B, may be connected to the second output section 36 of the second reduction unit 35. In this example, the first output section 26 of the first reduction unit 25 is composed of the part of the first case 40A and the first carrier 50A that is not connected to the connecting member 15. That is, one of the first case 40A and the first carrier 50A may be connected to the second reduction unit 35 by the connecting member 15, and the other of the first case 40A and the first carrier 50A may constitute the first output section 26.

[0082] The first case 40A and the second carrier 50B, or the connecting member 15 connecting the first carrier 50A and the second case 40B, does not need to be connected to the first output unit 26, nor does it need to be connected to the second output unit 36. In this example, the first output unit 26 of the first reduction unit 25 is made up of the part of the first case 40A and the first carrier 50A that is not connected to the connecting member 15. In this example, the second output unit 36 ​​of the second reduction unit 35 is made up of the part of the second case 40B and the second carrier 50B that is not connected to the connecting member 15. In other words, one of the first case 40A and the first carrier 50A may be connected to the second reduction unit 35 by a connecting member 15, and the other of the first case 40A and the first carrier 50A may constitute the first output unit 26, and one of the second case 40B and the second carrier 50B may be connected to the first reduction unit 25 by a connecting member 15, and the other of the second case 40B and the second carrier 50B may constitute the second output unit 36.

[0083] The connecting member 15 may be omitted. The connecting member 15 that is not connected to either the first output unit 26 or the second output unit 36 ​​may be omitted.

[0084] In the example shown in Figure 1, the connecting member 15 connects the first case 40A and the second case 40B. In the example shown in Figure 1, the first case 40A constitutes the first output unit 26. The first carrier 50A is fixed and its rotation is restricted. The first carrier 50A is connected to the drive source body 7. The second case 40B is connected to the second case 40B via the connecting member 15. The second carrier 50B constitutes the second output unit 36.

[0085] The connecting member 15 does not necessarily have to connect the first reduction unit 25 and the second reduction unit 35. The connecting member 15 may be connected to only one of the first reduction unit 25 and the second reduction unit 35. For example, as shown in Figure 3, which will be mentioned later, the connecting member 15 may be connected to only one of the first reduction unit 25 and the second reduction unit 35. In this example, when the connecting member 15 is connected to the output units 26 and 36, the connecting member 15 may hold the first retained member 26X or the second retained member 36X.

[0086] The reduction ratio of the first reduction unit 25 may be set as appropriate. By adjusting the reduction ratio of the first reduction unit 25, the rotational speed of the first output unit 26 can be set as appropriate. The reduction ratio of the second reduction unit 35 may be set as appropriate. By adjusting the reduction ratio of the second reduction unit 35, the rotational speed of the second output unit 36 ​​can be set as appropriate. By adjusting the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35, the ratio of the rotational speed of the first output unit 26 to the rotational speed of the second output unit 36 ​​can be set as appropriate. In the example shown in Figure 1, by adjusting the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35, the direction of rotation between the first output unit 26 and the second output unit 36 ​​can be made the same or the opposite.

[0087] The reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35 may be the same. The reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35 may be different.

[0088] Next, the operation of the drive unit 5 and the transmission unit 10 according to this embodiment will be described.

[0089] The drive shaft 8 of the drive source 6 rotates about the main rotation axis MRA. The drive shaft 8 is coaxially connected to the first input shaft 20. The first input shaft 20 is coaxially connected to the second input shaft 30. The first input shaft 20 and the second input shaft 30 rotate in sync with the drive shaft 8.

[0090] In the illustrated example, the first input shaft 20 is directly connected to the drive source 6. The second input shaft 30 is arranged coaxially with the first input shaft 20. The second input shaft 30 is directly connected to the first input shaft 20. Therefore, the dimensions of the combination of the two input shafts 20 and 30 in the axial direction D1 can be reduced, and consequently, the two reduction units 25 and 35 can be placed in close proximity in the axial direction D1. As a result, the transmission device 10 can be miniaturized in the axial direction D1. Furthermore, because the two reduction units 25 and 35 are placed in close proximity in the axial direction D1, the rigidity of the transmission device 10 is improved, and the load on the reduction units 25 and 35 and the input shafts 20 and 30 can be reduced. From this point of view as well, the reduction units 25 and 35 and the input shafts 20 and 30 can be made smaller and lighter.

[0091] The first input teeth 21 of the first input shaft 20 mesh with the input gear 79 of the first reduction unit 25. The rotation of the first input shaft 20 is transmitted to the shaft member 70. The rotation of the shaft member 70 causes the external gear 60 to eccentrically oscillate, and the external teeth 65 of the external gear 60 mesh with the internal teeth 45 of the case 40. Due to the difference in the number of teeth between the external teeth 65 and the internal teeth 45, the first carrier 50A that holds the external gear 60 and the first case 40A rotate relative to each other. The relative rotational speed between the first carrier 50A and the first case 40A is the value obtained by dividing the rotational speed of the first input shaft 20 by the reduction ratio of the first reduction unit 25.

[0092] The second input teeth 31 of the second input shaft 30 mesh with the input gear 79 of the second reduction unit 35. Similar to the first reduction unit 25, the rotation of the second input shaft 30 causes the second carrier 50B and the second case 40B to rotate relative to each other. The relative rotational speed between the second carrier 50B and the second case 40B is the value obtained by dividing the rotational speed of the second input shaft 30 by the reduction ratio of the second reduction unit 35.

[0093] In the example shown in Figure 1, the first carrier 50A of the first reduction unit 25 is fixed to the drive shaft 8 of the drive source 6 and is stationary. The first output unit 26 of the first reduction unit 25 is the first case 40A. In the first reduction unit 25, the rotation from the first input shaft 20 is reduced and output as the rotation of the first case 40A. The rotation of the first case 40A is in the opposite direction to the rotation of the drive shaft 8.

[0094] In the example shown in Figure 1, the second output section 36 of the second reduction section 35 is the second carrier 50B. The direction of rotation of the second carrier 50B relative to the second case 40B is the same as the direction of rotation of the first input shaft 20 and the second input shaft 30.

[0095] In the example shown in Figure 1, the connecting member 15 connects the first case 40A and the second case 40B. Therefore, the second case 40B rotates in the opposite direction to the rotation of the first input shaft 20 and the second input shaft 30, in synchronization with the first case 40A. Consequently, if the rotational speed (rpm) of the second carrier 50B in the second reduction unit 35 relative to the second case 40B is greater than the rotational speed (rpm) of the first case 40A in the first reduction unit 25 relative to the first carrier 50A, the second output unit 36 ​​(second carrier 50B) rotates in the opposite direction to the first output unit 26 (first case 40A). If the relative rotation speed (rpm) of the second carrier 50B in the second reduction unit 35 with respect to the second case 40B is less than the relative rotation speed (rpm) of the first case 40A in the first reduction unit 25 with respect to the first carrier 50A, the second output unit 36 ​​(second carrier 50B) rotates in the same direction as the first output unit 26 (first case 40A) at a lower rotation speed. If the rotational speed (rpm) of the second carrier 50B in the second reduction unit 35 relative to the second case 40B is the same as the rotational speed (rpm) of the first case 40A in the first reduction unit 25 relative to the first carrier 50A, the second output unit 36 ​​(second carrier 50B) and the first output unit 26 appear to stop.

[0096] Here, Table 1 shows the relationship between the input rotational speed (rpm) input from the drive source 6, the reduction ratio of the first reduction unit 25, the reduction ratio of the second reduction unit 35, the rotational speed of the first output unit 26, and the rotational speed of the second output unit 36 ​​in the drive unit 5 and transmission unit 10 shown in Figure 1. In Table 1, rotational speed (rpm) is defined as a positive value for rotation in the same direction as the rotation of the drive shaft 8, the first input shaft 20, and the second input shaft 30, and a negative value for rotation in the opposite direction to the rotation of the drive shaft 8, the first input shaft 20, and the second input shaft 30. The same applies to the positive and negative values ​​of rotational speeds below.

[0097] [Table 1]

[0098] In the drive unit 5 and transmission unit 10 shown in Figure 1, the first case 40A is connected to the second case 40B by a connecting member 15. The first output unit 26 is composed of the first case 40A, and the second output unit 36 ​​is composed of the second carrier 50B. In this example, by adjusting the reduction ratio of the first reduction unit 25 and the second reduction unit 35, the direction of output rotation of the first output unit 26 and the second output unit 36 ​​can be selected to be the same direction or opposite direction. The rotational speed (rpm) from the first output unit 26 can be adjusted by the reduction ratio of the first reduction unit 25. The rotational speed (rpm) from the second output unit 36 ​​can be adjusted by the reduction ratio of the first reduction unit 25 and the second reduction unit 35. In other words, with the drive unit 5 and transmission unit 10, the direction of output rotation and the rotational speed of output rotation from the first output unit 26 and the second output unit 36 ​​can be set with a high degree of freedom while using a single drive source 6.

[0099] As shown in Table 1, by making the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35 the same, the rotational speed of the second output unit 36 ​​can be set to 0 rpm. That is, the second output unit 36 ​​stops. By making the reduction ratio of the first reduction unit 25 twice the reduction ratio of the second reduction unit 35, the first output unit 26 and the second output unit 36 ​​can be rotated in opposite directions at the same rotational speed. By making the reduction ratio of the first reduction unit 25 n times the reduction ratio of the second reduction unit 35, the rotational speed of the second output unit 36 ​​can be set to -(n-1) times the rotational speed of the first output unit 26.

[0100] Unlike the example described above, in the drive unit 5 and transmission unit 10 shown in Figure 1, the first output unit 26 may be composed of a first carrier 50A, and the second output unit 36 ​​may be composed of a second case 40B. The second case 40B that constitutes the second output unit 36 ​​is connected to the first case 40A by a connecting member 15. The second carrier 50B of the second reduction unit 35 is fixed and stationary on the installation base or the like where the drive unit 5 is set. According to this example, by adjusting the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35, the direction of output rotation of the first output unit 26 and the second output unit 36 ​​can be selected to be the same direction or opposite direction. The rotational speed (rpm) from the first output unit 26 can be adjusted by the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35. The rotational speed (rpm) from the second output unit 36 ​​can be adjusted by the reduction ratio of the second reduction unit 35. Even with the drive unit 5 and transmission unit 10 in this example, the direction of output rotation and the rotational speed of output rotation from the first output unit 26 and the second output unit 36 ​​can be set with a high degree of freedom while using a single drive source 6. An example of the relationship between the input rotational speed (rpm) input from the drive source 6, the reduction ratio of the first reduction unit 25, the reduction ratio of the second reduction unit 35, the rotational speed of the first output unit 26, and the rotational speed of the second output unit 36 ​​in this example is shown in Table 2.

[0101] [Table 2]

[0102] As shown in Table 2, by making the reduction ratio of the first reduction unit 25 the same as the reduction ratio of the second reduction unit 35, the rotational speed of the first output unit 26 can be set to 0 rpm. That is, the first output unit 26 stops. By making the reduction ratio of the first reduction unit 25 half the reduction ratio of the second reduction unit 35, the first output unit 26 and the second output unit 36 ​​can be rotated in opposite directions at the same rotational speed. By making the reduction ratio of the second reduction unit 35 n times the reduction ratio of the first reduction unit 25, the rotational speed of the first output unit 26 can be set to -(n-1) times the rotational speed of the second output unit 36.

[0103] Unlike the example described above, in the drive unit 5 and transmission unit 10 shown in Figure 1, the first output unit 26 may be composed of a first carrier 50A, and the second output unit 36 ​​may be composed of a second carrier 50B. The first case 40A and the second case 40B are connected by a connecting member 15. One or more of the first case 40A, the second case 40B, and the connecting member 15 are fixed and stationary on the installation base or the like where the drive unit 5 is set. According to this example, the direction of output rotation of the first output unit 26 and the second output unit 36 ​​can be made the same, regardless of the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35. The rotational speed (rpm) from the first output unit 26 can be adjusted by the reduction ratio of the first reduction unit 25. The rotational speed (rpm) from the second output unit 36 ​​can be adjusted by the reduction ratio of the second reduction unit 35. Even with the drive unit 5 and transmission unit 10 in this example, the output rotation from the first output unit 26 and the second output unit 36 ​​can be set with a high degree of freedom while using a single drive source 6. An example of the relationship between the input rotational speed (rpm) input from the drive source 6, the reduction ratio of the first reduction unit 25, the reduction ratio of the second reduction unit 35, the rotational speed of the first output unit 26, and the rotational speed of the second output unit 36 ​​in this example is shown in Table 3.

[0104] [Table 3]

[0105] As shown in Table 3, by making the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35 the same, the first output unit 26 and the second output unit 36 ​​can be rotated in the same direction and at the same rotational speed. By making the reduction ratio of the first reduction unit 25 n times the reduction ratio of the second reduction unit 35, the rotational speed of the second output unit 36 ​​can be made n times the rotational speed of the first output unit 26.

[0106] Furthermore, unlike the example shown in Figure 1, the connecting member 15 may connect the first carrier 50A and the second carrier 50B, as shown in Figure 2.

[0107] In the drive unit 5 and transmission unit 10 shown in Figure 2, the first output unit 26 may be composed of a first carrier 50A, and the second output unit 36 ​​may be composed of a second case 40B. The first carrier 50A constituting the first output unit 26 is connected to the second carrier 50B by a connecting member 15. The first case 40A of the first reduction unit 25 is fixed and stationary on the installation base or the like where the drive unit 5 is set. In this example, by adjusting the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35, the direction of output rotation of the first output unit 26 and the second output unit 36 ​​can be selected to be the same direction or opposite direction. The rotational speed (rpm) from the first output unit 26 can be adjusted by the reduction ratio of the first reduction unit 25. The rotational speed (rpm) from the second output unit 36 ​​can be adjusted by the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35. In other words, with the drive unit 5 and transmission unit 10, the direction of output rotation and the rotational speed of output rotation from the first output unit 26 and the second output unit 36 ​​can be set with a high degree of freedom while using a single drive source 6. Table 4 shows an example of the relationship between the input rotational speed (rpm) input from the drive source 6, the reduction ratio of the first reduction unit 25, the reduction ratio of the second reduction unit 35, the rotational speed of the first output unit 26, and the rotational speed of the second output unit 36 ​​in this example.

[0108] [Table 4]

[0109] As shown in Table 4, by making the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35 the same, the rotational speed of the second output unit 36 ​​can be set to 0 rpm. That is, the second output unit 36 ​​stops. By making the reduction ratio of the first reduction unit 25 twice the reduction ratio of the second reduction unit 35, the first output unit 26 and the second output unit 36 ​​can be rotated in opposite directions at the same rotational speed. By making the reduction ratio of the first reduction unit 25 n times the reduction ratio of the second reduction unit 35, the rotational speed of the second output unit 36 ​​can be set to -(n-1) times the rotational speed of the first output unit 26.

[0110] In the drive unit 5 and transmission unit 10 shown in Figure 2, the first output unit 26 may be composed of a first case 40A, and the second output unit 36 ​​may be composed of a second carrier 50B. The second carrier 50B constituting the second output unit 36 ​​is connected to the first carrier 50A by a connecting member 15. The second case 40B of the second reduction unit 35 is fixed and stationary on the installation base or the like where the drive unit 5 is set. In this example, by adjusting the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35, the direction of output rotation of the first output unit 26 and the second output unit 36 ​​can be selected to be the same direction or opposite direction. The rotational speed (rpm) from the first output unit 26 can be adjusted by the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35. The rotational speed (rpm) from the second output unit 36 ​​can be adjusted by the reduction ratio of the second reduction unit 35. Even with the drive unit 5 and transmission unit 10 in this example, the direction of output rotation and the rotational speed of output rotation from the first output unit 26 and the second output unit 36 ​​can be set with a high degree of freedom while using a single drive source 6. An example of the relationship between the input rotational speed (rpm) input from the drive source 6, the reduction ratio of the first reduction unit 25, the reduction ratio of the second reduction unit 35, the rotational speed of the first output unit 26, and the rotational speed of the second output unit 36 ​​in this example is shown in Table 5.

[0111] [Table 5]

[0112] As shown in Table 5, by making the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35 the same, the rotational speed of the first output unit 26 can be set to 0 rpm. That is, the first output unit 26 stops. By making the reduction ratio of the first reduction unit 25 half the reduction ratio of the second reduction unit 35, the first output unit 26 and the second output unit 36 ​​can be rotated in opposite directions at the same rotational speed. By making the reduction ratio of the second reduction unit 35 n times the reduction ratio of the first reduction unit 25, the rotational speed of the first output unit 26 can be set to -(n-1) times the rotational speed of the second output unit 36.

[0113] In the drive unit 5 and transmission unit 10 shown in Figure 2, the first output unit 26 may be composed of a first case 40A, and the second output unit 36 ​​may be composed of a second case 40B. The first carrier 50A and the second carrier 50B are connected by a connecting member 15. One or more of the first carrier 50A, the second carrier 50B, and the connecting member 15 are fixed and stationary on the installation base or the like where the drive unit 5 is set. In this example, the direction of output rotation of the first output unit 26 and the second output unit 36 ​​can be made the same, regardless of the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35. The rotational speed (rpm) from the first output unit 26 can be adjusted by the reduction ratio of the first reduction unit 25. The rotational speed (rpm) from the second output unit 36 ​​can be adjusted by the reduction ratio of the second reduction unit 35. Even with the drive unit 5 and transmission unit 10 in this example, the output rotation from the first output unit 26 and the second output unit 36 ​​can be set with a high degree of freedom while using a single drive source 6. An example of the relationship between the input rotational speed (rpm) input from the drive source 6, the reduction ratio of the first reduction unit 25, the reduction ratio of the second reduction unit 35, the rotational speed of the first output unit 26, and the rotational speed of the second output unit 36 ​​in this example is shown in Table 6.

[0114] [Table 6]

[0115] As shown in Table 6, by making the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35 the same, the first output unit 26 and the second output unit 36 ​​can be rotated in the same direction and at the same rotational speed. By making the reduction ratio of the first reduction unit 25 n times the reduction ratio of the second reduction unit 35, the rotational speed of the second output unit 36 ​​can be made n times the rotational speed of the first output unit 26.

[0116] Furthermore, unlike the examples shown in Figures 1 and 2, the connecting member 15 may connect the first carrier 50A and the second case 40B, as shown in Figure 3.

[0117] In the drive unit 5 and transmission unit 10 shown in Figure 3, the first output unit 26 may be composed of a first case 40A, and the second output unit 36 ​​may be composed of a second carrier 50B. The first carrier 50A and the second case 40B are connected by a connecting member 15. One or more of the first carrier 50A, the second case 40B, and the connecting member 15 are fixed and stationary on the installation base or the like where the drive unit 5 is set. In this example, the direction of output rotation of the first output unit 26 and the second output unit 36 ​​can be reversed regardless of the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35. The rotational speed (rpm) from the first output unit 26 can be adjusted by the reduction ratio of the first reduction unit 25. The rotational speed (rpm) from the second output unit 36 ​​can be adjusted by the reduction ratio of the second reduction unit 35. Even with the drive unit 5 and transmission unit 10 in this example, the output rotation from the first output unit 26 and the second output unit 36 ​​can be set with a high degree of freedom while using a single drive source 6. Table 7 shows an example of the relationship between the input rotational speed (rpm) input from the drive source 6, the reduction ratio of the first reduction unit 25, the reduction ratio of the second reduction unit 35, the rotational speed of the first output unit 26, and the rotational speed of the second output unit 36 ​​in this example.

[0118] [Table 7]

[0119] As shown in Table 7, by making the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35 the same, the first output unit 26 and the second output unit 36 ​​can be rotated in opposite directions at the same rotational speed. By making the reduction ratio of the first reduction unit 25 n times the reduction ratio of the second reduction unit 35, the rotational speed of the second output unit 36 ​​can be made -n times the rotational speed of the first output unit 26.

[0120] In the example shown in Figure 3, the connecting member 15 is connected to the first case 40A which constitutes the first output unit 26. The connecting member 15 is also connected to the second carrier 50B which constitutes the second output unit 36.

[0121] In the drive unit 5 and transmission unit 10 shown in Figure 3, the first output unit 26 may be composed of a first carrier 50A, and the second output unit 36 ​​may be composed of a second carrier 50B. The first carrier 50A constituting the first output unit 26 is connected to the second case 40B by a connecting member 15. The first case 40A of the first reduction unit 25 is fixed and stationary on the installation base or the like where the drive unit 5 is set. In this example, the direction of output rotation of the first output unit 26 and the second output unit 36 ​​can be made the same regardless of the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35. The rotational speed (rpm) from the first output unit 26 can be adjusted by the reduction ratio of the first reduction unit 25. The rotational speed (rpm) from the second output unit 36 ​​can be adjusted by the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35. Even with the drive unit 5 and transmission unit 10 in this example, the output rotation from the first output unit 26 and the second output unit 36 ​​can be set with a high degree of freedom while using a single drive source 6. Table 8 shows an example of the relationship between the input rotational speed (rpm) input from the drive source 6, the reduction ratio of the first reduction unit 25, the reduction ratio of the second reduction unit 35, the rotational speed of the first output unit 26, and the rotational speed of the second output unit 36 ​​in this example.

[0122] [Table 8]

[0123] As shown in Table 8, by setting the reduction ratio of the first reduction unit 25 to n times the reduction ratio of the second reduction unit 35, the rotational speed of the second output unit 36 ​​can be made (n+1) times the rotational speed of the first output unit 26.

[0124] In the drive unit 5 and transmission unit 10 shown in Figure 3, the first output unit 26 may be composed of a first case 40A, and the second output unit 36 ​​may be composed of a second case 40B. The second case 40B, which constitutes the second output unit 36, is connected to the first carrier 50A by a connecting member 15. The second carrier 50B of the second reduction unit 35 is fixed and stationary on the installation base or the like where the drive unit 5 is set. According to this example, the direction of output rotation of the first output unit 26 and the second output unit 36 ​​can be made the same, regardless of the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35. The rotational speed (rpm) from the first output unit 26 can be adjusted by the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35. The rotational speed (rpm) from the second output unit 36 ​​can be adjusted by the reduction ratio of the second reduction unit 35. Even with the drive unit 5 and transmission unit 10 in this example, the output rotation from the first output unit 26 and the second output unit 36 ​​can be set with a high degree of freedom while using a single drive source 6. An example of the relationship between the input rotational speed (rpm) input from the drive source 6, the reduction ratio of the first reduction unit 25, the reduction ratio of the second reduction unit 35, the rotational speed of the first output unit 26, and the rotational speed of the second output unit 36 ​​in this example is shown in Table 9.

[0125] [Table 9]

[0126] As shown in Table 9, by setting the reduction ratio of the second reduction unit 35 to n times the reduction ratio of the first reduction unit 25, the rotational speed of the first output unit 26 can be made (n+1) times the rotational speed of the second output unit 36.

[0127] Furthermore, unlike the examples shown in Figures 1 to 3, the connecting member 15 may connect the first case 40A and the second carrier 50B, as shown in Figure 4.

[0128] In the drive unit 5 and transmission unit 10 shown in Figure 4, the first output unit 26 may be composed of a first carrier 50A, and the second output unit 36 ​​may be composed of a second case 40B. The first case 40A and the second carrier 50B are connected by a connecting member 15. One or more of the first case 40A, the second carrier 50B, and the connecting member 15 are fixed and stationary on the installation base or the like where the drive unit 5 is set. In this example, the direction of output rotation of the first output unit 26 and the second output unit 36 ​​can be reversed regardless of the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35. The rotational speed (rpm) from the first output unit 26 can be adjusted by the reduction ratio of the first reduction unit 25. The rotational speed (rpm) from the second output unit 36 ​​can be adjusted by the reduction ratio of the second reduction unit 35. Even with the drive unit 5 and transmission unit 10 in this example, the output rotation from the first output unit 26 and the second output unit 36 ​​can be set with a high degree of freedom while using a single drive source 6. Table 10 shows an example of the relationship between the input rotational speed (rpm) input from the drive source 6, the reduction ratio of the first reduction unit 25, the reduction ratio of the second reduction unit 35, the rotational speed of the first output unit 26, and the rotational speed of the second output unit 36 ​​in this example.

[0129] [Table 10]

[0130] As shown in Table 10, by making the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35 the same, the first output unit 26 and the second output unit 36 ​​can be rotated in opposite directions at the same rotational speed. By making the reduction ratio of the first reduction unit 25 n times the reduction ratio of the second reduction unit 35, the rotational speed of the second output unit 36 ​​can be made -n times the rotational speed of the first output unit 26.

[0131] In the example shown in Figure 4, the connecting member 15 is connected to the second case 40B which constitutes the second output unit 36.

[0132] In the drive unit 5 and transmission unit 10 shown in Figure 4, the first output unit 26 may be composed of a first case 40A, and the second output unit 36 ​​may be composed of a second case 40B. The first case 40A constituting the first output unit 26 is connected to the second carrier 50B by a connecting member 15. The first carrier 50A of the first reduction unit 25 is fixed and stationary on the installation base or the like where the drive unit 5 is set. In this example, the direction of output rotation of the first output unit 26 and the second output unit 36 ​​can be made the same regardless of the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35. The rotational speed (rpm) from the first output unit 26 can be adjusted by the reduction ratio of the first reduction unit 25. The rotational speed (rpm) from the second output unit 36 ​​can be adjusted by the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35. Even with the drive unit 5 and transmission unit 10 in this example, the output rotation from the first output unit 26 and the second output unit 36 ​​can be set with a high degree of freedom while using a single drive source 6. Table 11 shows an example of the relationship between the input rotational speed (rpm) input from the drive source 6, the reduction ratio of the first reduction unit 25, the reduction ratio of the second reduction unit 35, the rotational speed of the first output unit 26, and the rotational speed of the second output unit 36 ​​in this example.

[0133] [Table 11]

[0134] As shown in Table 11, by setting the reduction ratio of the first reduction unit 25 to n times the reduction ratio of the second reduction unit 35, the rotational speed of the second output unit 36 ​​can be made (n+1) times the rotational speed of the first output unit 26.

[0135] In the drive unit 5 and transmission unit 10 shown in Figure 4, the first output unit 26 may be composed of a first carrier 50A, and the second output unit 36 ​​may be composed of a second carrier 50B. The second carrier 50B constituting the second output unit 36 ​​is connected to the first case 40A by a connecting member 15. The second case 40B of the second reduction unit 35 is fixed and stationary on the installation base or the like where the drive unit 5 is set. According to this example, the direction of output rotation of the first output unit 26 and the second output unit 36 ​​can be made the same regardless of the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35. The rotational speed (rpm) from the first output unit 26 can be adjusted by the reduction ratio of the first reduction unit 25 and the reduction ratio of the second reduction unit 35. The rotational speed (rpm) from the second output unit 36 ​​can be adjusted by the reduction ratio of the second reduction unit 35. Even with the drive unit 5 and transmission unit 10 in this example, the output rotation from the first output unit 26 and the second output unit 36 ​​can be set with a high degree of freedom while using a single drive source 6. An example of the relationship between the input rotational speed (rpm) input from the drive source 6, the reduction ratio of the first reduction unit 25, the reduction ratio of the second reduction unit 35, the rotational speed of the first output unit 26, and the rotational speed of the second output unit 36 ​​in this example is shown in Table 12.

[0136] [Table 12]

[0137] As shown in Table 12, by setting the reduction ratio of the second reduction unit 35 to n times the reduction ratio of the first reduction unit 25, the rotational speed of the first output unit 26 can be set to (n+1) times the rotational speed of the second output unit 36.

[0138] As described above, with the transmission device 10 in which two reduction units 25 and 35 are arranged coaxially opposite each other, the rotation input from a single drive source 6 can be reduced by appropriately setting the reduction ratio of the two reduction units 25 and 35, and the direction and speed of rotation output from the first output unit 26 and the direction and speed of rotation output from the second output unit 36 ​​can be appropriately adjusted.

[0139] In the embodiment described above, the transmission device 10 is • One input shaft (first input shaft) 20 connected to the drive source 6, • One input axis (second input axis) 30 is directly connected to one input axis 20, A reduction unit (first reduction unit) 25 includes one output unit (first output unit) 26 that reduces the rotation of one input shaft 20 and outputs the result, The system includes another reduction unit 35, which includes another output unit (second output unit) 36 that reduces the rotation of another input shaft 30 and outputs the result, and the other output unit 36 ​​is arranged coaxially with the first output unit 26.

[0140] According to this embodiment, the other input shaft (second input shaft) 30 is arranged coaxially with one input unit (first input shaft) 20 and is directly connected to the input unit (first input shaft) 20. Therefore, the dimensions of the combination of the two input shafts 20 and 30 in the axial direction D1 can be reduced, and consequently, the two reduction units 25 and 35 can be placed in close proximity in the axial direction D1. As a result, the transmission device 10 can be made smaller in the axial direction D1. Furthermore, because the two reduction units 25 and 35 are placed in close proximity in the axial direction D1, the rigidity of the transmission device 10 is improved, and the load on the reduction units 25 and 35 and the input shafts 20 and 30 can be reduced. From this point of view as well, the reduction units 25 and 35 and the input shafts 20 and 30 can be made smaller and lighter.

[0141] In the specific example of the present embodiment described above, the transmission device 10 may include a connecting member 15 located between one reduction unit 25 and another reduction unit 35 in the axial direction D1, and connected to one output unit 26 or another output unit 36. According to this specific example, output rotation can be extracted via the connecting member 15. This expands the range of application of the transmission device 10 and increases the degree of freedom in its installation. The connecting member 15 can be positioned using the space between the two reduction units 25 and 35. Therefore, the design, positioning, and application of the transmission device 10 can be improved while suppressing an increase in the size of the transmission device 10.

[0142] In the specific example of this implementation described above, one input shaft 20 and another input shaft 30 may be connected between one reduction unit 25 and another reduction unit 35 in the axial direction D1. The two input shafts 20 and 30 can be connected by utilizing the space between the two reduction units 25 and 35. Therefore, the two input shafts 20 and 30 can be connected appropriately and stably. The generation of vibration and abnormal noise in the transmission device 10 can be reduced, and the lifespan of the transmission device 10 can be extended.

[0143] In the specific example of this implementation described above, one of the input shafts 20 and the other input shaft 30 may include a cylindrical portion 18 into which the other is inserted. According to this specific example, the axial dimension D1 of the combination of the input shaft 20 and the other input shaft 30 can be shortened. Furthermore, by using a combination of the cylindrical portion 18 and a member inserted into the cylindrical portion 18, the design freedom for the outer diameter and number of teeth of the two input shafts 20 and 30 is increased. Therefore, the direction and rotational speed output from the two output units 26 and 36 can be set with a greater degree of freedom.

[0144] In the specific example of the present invention described above, the transmission device 10 may include a connecting member 15 located between one reduction unit 25 and another reduction unit 35 in the axial direction D1 and connected to at least one of the reduction unit 25 and the other reduction unit 35, and a bearing 17 held by the connecting member 15 and supporting one of the input shafts 20 and the other input shaft 30. The two input shafts 20 and 30 receive a torque load of input torque from a drive source (e.g., a motor) 6. The two input shafts 20 and 30 can rotate stably at high speed by being supported by the bearing 17. In addition, the connecting member 15 is connected to at least one of the reduction unit 25 and the other reduction unit 35. Therefore, the relative position of the input shafts 20 and 30 with respect to the reduction units 25 and 35 can be stably maintained. As a result, vibration and noise generation of the transmission device 10 can be reduced and the lifespan of the transmission device 10 can be extended.

[0145] In the specific example of the present implementation described above, one input shaft 20 may include teeth 21 that mesh with one reduction unit 25, and another input shaft 30 may include teeth 31 that mesh with another reduction unit 35. The bearing 17 supports one input shaft 20 or the other input shaft 30 at a position between the teeth (first input teeth) 21 of one input shaft 20 and the teeth (second input teeth) 31 of the other input shaft 30 in the axial direction D1. By appropriately designing the teeth 21 and 31 of the two input shafts 20 and 30, the rotational speed output from each output unit 26 and 36 can be adjusted. By utilizing the area between the teeth 21 and 31 of the two input shafts 20 and 30 that are not provided, one of the two input shafts 20 and 30 can be supported by the bearing 17. In other words, the input shafts 20 and 30 can be stably supported by the bearing 17 while suppressing the size of the transmission device 10. Furthermore, with this configuration, the first input shaft 20 or the second input shaft 30 can be supported by the bearing 17 near the meshing portion between the first input shaft 20 and the first reduction unit 25 by the first input teeth 21. At the same time, the first input shaft 20 or the second input shaft 30 can be supported by the bearing 17 near the meshing portion between the second input shaft 30 and the second reduction unit 35 by the second input teeth 31. Therefore, the first input shaft 20 and the second input shaft 30 can be stably supported by the bearing 17.

[0146] In the specific example of the present invention described above, one of the input shafts 20 and the other input shaft 30 may include a cylindrical portion 18 into which the other is inserted, and the bearing 17 may support the cylindrical portion 18. By the bearing 17 supporting the cylindrical portion 18, not only the input shaft constituting the cylindrical portion 18 but also the other input shaft inserted into the cylindrical portion 18 is stably supported by the bearing 17. In other words, the two input shafts 20 and 30 can be supported more stably by the bearing 17.

[0147] In the above-described specific example of this embodiment, one reduction unit 25 includes a case 40A and a carrier 50A, and one output unit 26 may be composed of either the case 40A or the carrier 50A of the reduction unit 25. Another reduction unit 35 includes a case 40B and a second carrier 50B, and another second output unit 36 ​​may be composed of either the case 40B or the carrier 50B. The transmission device 10 may include a connecting member 15 that connects the case 40A of one reduction unit 25 to the case 40B of another reduction unit 25, or a connecting member 15 that connects the carrier 50A of one reduction unit 25 to the carrier 50B of another reduction unit 35. According to this specific example, as will be explained below, the output rotation from the two output units 26 and 36 can be set with a high degree of freedom while using a single drive source 6.

[0148] In this specific example, when the connecting member 15 is stationary and not connected to the two output units 26 and 36, the two output units 26 and 36 can output rotation in the same direction, regardless of the reduction ratio of the reduction units 25 and 35. When the connecting member 15 is stationary and not connected to the two output units 26 and 36, the rotational speed of the rotation output from each output unit can be independently adjusted by the reduction ratio of each reduction unit 25 and 35, without being affected by the rotational speed of the rotation output from the other output unit.

[0149] In this specific example, when the connecting member 15 is connected to either of the output units 26 or 36, the rotation output from the two output units 26 or 36 can be made to be in the same direction or in opposite directions by adjusting the reduction ratio of the two reduction units 25 or 35. When the connecting member 15 is connected to either of the output units 26 or 36, the rotational speed of the rotation output from the two output units 26 or 36 can be adjusted by the reduction ratio of the two reduction units 25 or 35.

[0150] In the above-described specific example of this embodiment, one reduction unit 25 includes a case 40A and a carrier 50A, and one output unit 26 may be composed of either the case 40A or the carrier 50A of the reduction unit 25. Another reduction unit 35 includes a case 40B and a second carrier 50B, and another second output unit 36 ​​may be composed of either the case 40B or the carrier 50B. The transmission device 10 may include a connecting member 15 that connects the case 40A of one reduction unit 25 to the second carrier 50B of the other reduction unit 25, or a connecting member 15 that connects the carrier 50A of one reduction unit 25 to the second case 40B of the other reduction unit 35. According to this specific example, as will be explained below, the output rotation from the two output units 26 and 36 can be set with a high degree of freedom while using a single drive source 6.

[0151] In this specific example, when the connecting member 15 is stationary and not connected to the two output units 26 and 36, it is possible to output rotations in opposite directions from the two output units 26 and 36, regardless of the reduction ratio of the reduction units 25 and 35. When the connecting member 15 is stationary and not connected to the two output units 26 and 36, the rotational speed of the rotation output from each output unit can be independently adjusted by the reduction ratio of each reduction unit 25 and 35, without being affected by the rotational speed of the rotation output from the other output units.

[0152] In this specific example, when the connecting member 15 is connected to either of the output units 26 or 36, rotations in the same direction can be output from both output units 26 or 36, regardless of the reduction ratio of the reduction units 25 or 35. When the connecting member 15 is connected to either of the output units 26 or 36, the rotational speed of the rotations output from the two output units 26 or 36 can be adjusted by the reduction ratio of the two reduction units 25 or 35.

[0153] In the specific example of this implementation described above, the reduction ratio of one reduction unit 25, 35 may be different from the reduction ratio of the other reduction unit 25, 35. By adjusting the reduction ratio of the two reduction units 25, 35, rotation in a desired direction and at a desired rotational speed can be output from each output unit 26, 36.

[0154] Although this embodiment has been described with reference to several specific examples, this embodiment is not limited to these examples. This embodiment can be implemented with various other specific examples, and various omissions, substitutions, modifications, and additions can be made without departing from its essence.

[0155] Among the embodiments disclosed herein, those composed of multiple objects may be integrated, and conversely, those composed of a single object may be divided into multiple objects. Whether or not they are integrated, the invention can be constructed in a way that achieves its objective. [Explanation of Symbols]

[0156] D1: Axial direction, 6: Drive source, 8: Drive shaft, 10: Transmission device, 15: Connecting member, 17: Bearing, 18: Cylindrical part, 20: One input shaft, first input shaft, 21: First input tooth, 25: One reduction unit, first reduction unit, 26: One output unit, first output unit, 30: Other input shaft, second input shaft, 31: Second input tooth, 35: Other reduction unit, second reduction unit, 36: Other output unit, second output unit, 40: Case, 40A: First case, 40B: Second case, 50: Carrier, 50A: First carrier, 50B: Second carrier

Claims

1. One input shaft connected to the drive source, One input shaft directly connected to the aforementioned one input shaft, A reduction unit including an output unit that reduces the rotation of one input shaft and outputs the result, A transmission device comprising: another reduction unit, which includes another output unit that reduces the rotation of the other input shaft and outputs the result, wherein the other output unit is arranged coaxially with the output unit.

2. The transmission device according to claim 1, further comprising a connecting member located between one reduction unit and the other reduction unit in the axial direction, and connected to one output unit or the other output unit.

3. The transmission device according to claim 1, wherein one input shaft and the other input shaft are connected between the one reduction unit and the other reduction unit in the axial direction.

4. The transmission device according to claim 3, wherein one of the input shafts and the other input shaft includes a cylindrical portion into which the other is inserted.

5. A connecting member located between one reduction gear and the other reduction gear in the axial direction, and connected to at least one of the one reduction gear and the other reduction gear, The transmission device according to claim 1, further comprising a bearing held by the connecting member and supporting one of the one input shaft and the other input shaft.

6. The aforementioned input shaft includes teeth that mesh with the aforementioned reduction unit, The other input shaft includes teeth that mesh with the other reduction unit, The transmission device according to claim 5, wherein the bearing supports one input shaft or the other input shaft at a position between the teeth of one input shaft and the teeth of the other input shaft in the axial direction.

7. The aforementioned reduction unit includes a case and a carrier that is rotatable relative to the case, The aforementioned output unit is composed of either the case or the carrier of the aforementioned reduction unit. The other reduction gear includes a case and a carrier that is rotatable relative to the case, The other output unit is comprised of either the case or the carrier of the other reduction unit. The transmission device according to claim 1, further comprising a connecting member for connecting the case of one reduction unit with the case of the other reduction unit, or for connecting the carrier of one reduction unit with the carrier of the other reduction unit.

8. The aforementioned reduction unit includes a case and a carrier that is rotatable relative to the case, The aforementioned output unit is composed of either the case or the carrier of the aforementioned reduction unit. The other reduction gear includes a case and a carrier that is rotatable relative to the case, The other output unit is comprised of either the case or the carrier of the other reduction unit. The transmission device according to claim 1, further comprising a connecting member that connects the case of one reduction unit to the carrier of the other reduction unit, or a connecting member that connects the carrier of one reduction unit to the case of the other reduction unit.

9. The transmission device according to claim 1, wherein the reduction ratio of one of the reduction units is different from the reduction ratio of the other reduction unit.

10. A transmission device according to any one of claims 1 to 9, A drive device comprising a drive source including a drive shaft directly connected to one of the input shafts.

Images