JP7414267B2 - telescopic arm device - Google Patents

Description

Application of Article 30, Paragraph 2 of the Patent Act Website publication date February 3, 2020 Website address https://www. robodex. jp/ja-jp. html https://jan2020. tems-system. com/exhiSearch/ROBO/jp/Details? id=fTVhwiwYGfo%3D&type=2&rel=undefined https://www. google. com/maps/uv? hl=ja&pb=! 1s0x60186061c96a079d%3A0xc14b86f455048f41!3m1!7e115!4shttps%3A%2F%2Flh5. googleusercontent. com%2Fp%2FAF1QipMDWPVJY5DmkyhsxpII8tgYwVwIHd9FT-O0FgIp%3Dw224-h160-k-no! 5z44Kr440D440I440p440z440J44K4440j440R440zIC0gR29vZ2xlI0akn0e0og! 15sCAQ&imagekey=! 1e10!2sAF1QipNvksVlvtAVp0Yiz4zhuCBc0RKKyzkAger9Ha68&sa=X&ved=2ahUKEwjer8KlurbnAhVCZt4KHb-uCfUQoiowC3oECA8QBg&cshi d=1580769991384526# https://www. google. com/search? sxsrf=ACYBGNSBiW4RElTnxpsNTgR6dsuFp9yhWg%3A1580770341465&source=hp&ei=JaQ4XruNGtvl-Aa1irioBg&q=%E3%82%AB%E3%83%83%E3%83%8 8%E3%83%A9%E3%83%B3%E3%83%89%E3 %82%B8%E3%83%A3%E3%83%91%E3%83%B3&oq=&gs_l=psy-ab. 1.0.35i362i39110.0.0. ．． 1520. ．． ．． 2.0. ．． 0.0.0. ．． ．． ．． ．． ．． ．． 0. ．． ．． ．． ．． ．． gws-wiz. ．． ．． ．． ．． 10. baCnvqcy2R4#lpstate=pid:1787953264220065965,av Exhibition name 4th Robotex Robot Development and Utilization Exhibition Exhibition date February 12th to 14th, 2020

The present invention relates to a robot arm device in which a wrist portion is attached to an extendable arm portion.

2. Description of the Related Art A robot arm device has been developed in which an arm part is expanded and contracted by the torque of a drive device such as a motor, and a hand part for gripping a workpiece is attached to the end of the arm part. A wrist portion for rotating the hand portion relative to the arm portion may be provided between the arm portion and the hand portion. Examples include the following:

Japanese Patent Application Publication No. 2016-203289 Japanese Patent Application Publication No. 2019-196775

The device of Patent Document 1 is a robot arm device in which a hand portion for grasping a workpiece is connected to an arm portion, and a wire is sent out by driving a motor located on the base end side of the arm portion. Alternatively, it is wound up and the arm part is expanded and contracted.

The device of Patent Document 2 is a robot arm device in which a hand portion is connected to an arm portion, and a plurality of U-shaped cross sections connected to a first column consisting of a plurality of connected plates are moved by a motor. A second frame row made up of members is sent out or rewound, and the first and second frame rows are joined or disassembled, thereby expanding and contracting the arm portion.

The robot arm device of Patent Document 1 is capable of extending and contracting the arm section and operating the gripping mechanism of the hand section using a motor installed on the base end side, but a wrist section for rotating the hand section is not provided. Therefore, the hand section cannot be freely rotated.

On the other hand, the robot arm device of Patent Document 2 has a configuration in which the first frame row and the second frame row are joined or disassembled, so a space is required to store the first frame row and the second frame row. , there is a tendency to increase in size, and since a drive device for rotating the wrist portion is connected to the wrist portion, an uneven load is likely to be applied to the arm portion, and the wrist portion also tends to increase in size.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, it is an object of the present invention to provide a robot arm device that is compact and does not easily apply unbalanced loads to the arm portion, and can freely rotate the hand portion.

The present invention is a robot arm device having a base body, an extendable arm part connected to the base body, and a wrist part connected to the distal end side of the arm part,
The wrist portion includes a base, a first pulley rotatably provided on the base, and a hand attachment portion connected to the first pulley,
The base body includes at least one drive motor, at least one first differential motor, a first rotating member and a second rotating member for feeding or retracting the first linear member, and the first and second rotating members. First and second planetary gear mechanisms respectively configured of rotatable first and second sun gears, first and second planetary gears, and first and second ring gears corresponding to the rotating member,
the first linear member is hung on the first pulley;
The first rotating member is configured such that torque is transmitted from any one of the first sun gear, first planetary gear, or first ring gear,
The second rotating member is configured such that torque is transmitted from either the second sun gear, the second planetary gear, or the second ring gear,
The torque from the drive motor is transmitted to the first and second rotating members other than the first and second sun gears, first and second planetary gears, or first and second ring gears that transmit torque to the first and second rotating members. configured to be transmitted to any one of the sun gear, the first planet gear, or the first ring gear and the second sun gear, the second planet gear, or the second ring gear,
The torque from the first differential motor is not transmitted to the first and second sun gears, first and second planetary gears, or first and second ring gears that transmit torque to the first and second rotating members. , and the first sun gear, first planetary gear, or third ring gear is not the first and second sun gears, first and second planetary gears, or first and second ring gears to which torque is transmitted from the drive motor. configured to be transmitted to either one of the first ring gear and the second sun gear, second planetary gear, or second ring gear,
When the arm part extends, the first and second rotating members are rotated by the torque from the drive motor, and the first linear member is delivered at a delivery amount corresponding to the amount of extension of the arm part,
When the arm part contracts, the first and second rotating members are rotated by the torque from the drive motor, and the first linear member is pulled back by an amount corresponding to the amount of contraction of the arm part,
The torque from the first differential motor is configured to rotate the first and second rotating members, send out and pull back the first linear member, and rotate the first pulley. The above-mentioned problem has been solved by the characteristic robot arm device.

According to the robot arm device of the present invention, the drive motor and the first differential motor are provided on the base body, and the first differential motor sends out and pulls back the first linear member and rotates the first pulley. The hand mounting portion can be rotated in the rotational direction of the first pulley. Therefore, since there is no need to provide a motor for rotating the hand attachment portion on the wrist portion, an unbalanced load is less likely to be applied to the arm portion, resulting in a compact design.

The first pulley includes a first bevel gear, the hand mounting portion is provided with the hand bevel gear, and the hand mounting portion is rotatable about an axis perpendicular to the axis of the first bevel gear; By meshing and connecting the first bevel gear and the hand bevel gear, the hand attachment part can be rotated about an axis perpendicular to the axis of the first bevel gear.

Further, the wrist portion includes a second pulley having a symmetrical structure with the first pulley, and the base body includes the first linear member, the first rotating member, and a second linear member having a symmetrical structure with the second rotating member. If the configuration is such that the second linear member is sent out and pulled back by the second differential motor and the second pulley is rotated, the first linear member and the second By rotating the first pulley and the second pulley using the linear member, the hand mounting portion can be reliably rotated.

Further, the hand mounting portion is rotatably provided around an axis parallel to the axis of the first bevel gear, and the base body further includes a second differential motor that transmits torque to the first to fourth rotating members. By driving one or both of the first differential motor and the second differential motor, the hand mounting portion can be rotated about two orthogonal axes.

Furthermore, if the arm section is configured to extend and contract using the torque from the drive motor, there is no need to provide a separate motor for extending and contracting the arm section, so that the robot arm device can be made more compact.

Further, the arm portion includes a first plate and a second plate, and the first plate is configured to rotate by torque from the drive motor and has a hollow first nut member provided with a thread on the inner diameter side. If the second plate is configured to include a rod-shaped first screw member that is screwed into the thread on the inner diameter side of the first nut member, the first nut member is rotated by the torque of the drive motor, and the rotation thereof is Depending on the direction, the second plate can be moved away from or closer to the first plate. Therefore, since there is no need for a space for storing the first frame row and the second frame row as shown in Patent Document 2, the robot arm device can be made relatively compact. Moreover, a third plate can be further provided in the same manner.

FIG. 1 is a front view of the robot arm device of the present invention. FIG. 2 is a plan view of FIG. 1. FIG. 2 is an enlarged plan view of the arm portion of FIG. 1; FIG. 2 is an enlarged view of the arm portion of FIG. 1. FIG. 2 is an enlarged internal view of the base portion of FIG. 1; FIG. 5 is a cross-sectional view taken along line A-B-C-D-E-F in FIG. 5. FIG. 5 is a cross-sectional view taken along line A-B-C-G-H-I-J in FIG. FIG. 2 is a longitudinal sectional view of the first differential motor portion of FIG. 1; FIG. 2 is a vertical cross-sectional view of the second differential motor portion of FIG. 1; FIG. 2 is a developed view of the arm portion of FIG. 1;

Embodiments of the present invention will be described with reference to FIGS. 1 to 10. However, the present invention is not limited to this embodiment.

As shown in FIGS. 1 and 2, the robot arm device 100 includes a base body 10, an extendable arm portion 20 connected to the base body 10, and a wrist portion 30 connected to the distal end side of the arm portion 20. There is. The base body 10 includes a drive motor M2, a first differential motor M3, and a second differential motor M4. Furthermore, the arm portion 20 is configured to be extendable and retractable, as shown by the broken line. Details regarding these will be described later. Note that the robot arm device 100 can be configured so that the arm section 20 can rotate around a horizontal axis or a vertical axis by using the power of the motor M1 (as indicated by the broken line in FIGS. 1 and 2). (see section).

As shown in FIG. 3, the wrist portion 30 has a base portion 32 connected to the arm portion 20. A first pulley 34 and a second pulley 36 are rotatably provided on the base 32. The first pulley 34 and the second pulley 36 are connected to a first bevel gear 35 and a second bevel gear 37, respectively. A hand bevel gear 39 is connected to the hand mounting portion 38 . The hand portion mounting portion 38 is connected to the first pulley 34 and the second pulley 36 by the hand portion bevel gear 39 meshing with the first bevel gear 35 and the second bevel gear 37. The hand attachment portion 38 may be integrated with a hand portion (not shown) such as an actuator that grips a workpiece, or the hand portion may be attached to the hand attachment portion 38. Note that a configuration in which the second pulley 36 is not provided or a configuration in which the hand portion attachment portion 38 is connected to the first pulley 34 and the second pulley 36 without using a bevel gear are also possible.

The first bevel gear 35 and the second bevel gear 37 have parallel axes of rotation, preferably collinear axes of rotation as shown. Further, the wrist portion 30 includes a first mounting shaft 33 located on the rotation axis of the first bevel gear 35 and the second bevel gear 37. The first bevel gear 35 and the second bevel gear 37 are configured to be rotatable with respect to the first attachment shaft 33. The hand attachment portion 38 can be connected to the first attachment shaft 33 via a second attachment shaft 31 that is rotatable with respect to the first attachment shaft 33 . With this configuration, the hand portion attachment portion 38 is provided rotatably around an axis perpendicular to the axes of the first bevel gear 35 and the second bevel gear 37.

As shown in FIG. 1 , the base body 10 includes a first rotating member 42 and a second rotating member 44 . The first rotating member 42 and the second rotating member 44 are configured so that the first linear member 46 can be sent out or pulled back by their rotation. The first linear member 46 is hung on the first pulley 34 so as to maintain an appropriate tension (see also FIG. 4). Similarly, the base body 10 can include a third rotating member 52 and a fourth rotating member 54, so that the second linear member 56 hooked on the second pulley 36 can be sent out or pulled back. (See Figure 3). Note that it is preferable that the first linear member 46 and the second linear member 56 be wrapped around each of the first pulley 34 and the second pulley 36 one turn or more to prevent slipping. Although the first rotating member 42 and the second rotating member 44 have the same diameter, they have different diameters, and the rotational speeds of the drive motor M2, first differential motor M3, and second differential motor M4 are adjusted. It is also possible.

Next, how the first linear member 46 and the second linear member 56 are sent out or pulled back will be explained. FIG. 5 is a diagram showing the internal structure of the first rotating member 42 and second rotating member 44 portion of the base body 10. As shown in FIG. As shown in FIG. 5, inside the base body 10, a first planetary gear mechanism 62 and a second planetary gear mechanism are provided, which correspond to the first rotating member 42 and the second rotating member 44 (see FIG. 1), respectively. 82 is provided. The torque of the drive motor M2 (see FIG. 1) is configured to be transmitted to the drive torque input gear 102, and is transmitted from the drive torque input gear 102 to the first planetary gear mechanism 62 via the first gear train 104. It is also transmitted to the second planetary gear mechanism 82 via the second gear train 106.

As shown in FIG. 6, the first planetary gear mechanism 62 includes a first sun gear 64, a first planetary gear 66, and a first ring gear 68, which are each rotatably provided. The first ring gear 68 includes gears on the inner circumferential side and the outer circumferential side, and the gear on the inner circumferential side meshes with the first planetary gear 66. Torque from the first gear train 104 is transmitted to the first sun gear 64 of the first planetary gear mechanism 62 , causing the first planet gear 66 to revolve relative to the first sun gear 64 . The first planetary gear 66 is connected to the first rotating member 42, and torque from the first planetary gear 66 is transmitted to the first rotating member 42, causing the first rotating member 42 to rotate.

Similarly, a third planetary gear mechanism 72 corresponding to the third rotating member 52 is provided, and the third planetary gear mechanism 72 includes a third sun gear 74, a third planet gear 76, and a third ring gear 78. Each of them is configured to be rotatable. The third ring gear 78 includes gears on each of the inner circumferential side and the outer circumferential side, and the gear on the inner circumferential side meshes with the third planetary gear 76. The torque from the first gear train 104 is also transmitted to the third sun gear 74 of the third planetary gear mechanism 72 , causing the third planetary gear 76 to revolve relative to the third sun gear 74 . The third planetary gear 76 is connected to the third rotating member 52, and torque from the third planetary gear 76 is transmitted to the third rotating member 52, causing the third rotating member 52 to rotate.

As shown in FIG. 7, the second planetary gear mechanism 82 includes a second sun gear 84, a second planetary gear 86, and a second ring gear 88, which are each rotatably provided. The second ring gear 88 includes gears on the inner circumferential side and the outer circumferential side, and the gear on the inner circumferential side meshes with the second planetary gear 86. Torque from the second gear train 106 is transmitted to the second sun gear 84 of the second planetary gear mechanism 82 , causing the second planet gear 86 to revolve relative to the second sun gear 84 . The second planetary gear 86 is connected to the second rotating member 44 , and torque from the second planetary gear 86 is transmitted to the second rotating member 44 to rotate the second rotating member 44 .

Similarly, a fourth planetary gear mechanism 92 corresponding to the fourth rotating member 54 is provided, and the fourth planetary gear mechanism 92 includes a fourth sun gear 94, a fourth planet gear 96, and a fourth ring gear 98. Each of them is configured to be rotatable. The fourth ring gear 98 includes gears on the inner circumferential side and the outer circumferential side, and the gear on the inner circumferential side meshes with the fourth planetary gear 96. The torque from the second gear train 106 is also transmitted to the fourth sun gear 94 of the fourth planetary gear mechanism 92 , causing the fourth planetary gear 96 to revolve relative to the fourth sun gear 94 . The fourth planetary gear 96 is connected to the fourth rotating member 54, and torque from the fourth planetary gear 96 is transmitted to the fourth rotating member 54, causing the fourth rotating member 54 to rotate.

In the case of this embodiment, as shown in FIG. 1, the winding directions of the first linear member 46 with respect to the first rotating member 42 and the second rotating member 44 are different from each other. Specifically, in the front view of FIG. 1, the first rotating member 42 winds the first linear member 46 in a right-handed manner, and the second rotating member 44 winds the first linear member 46 in a left-handed manner. It is configured as follows. In the case of such a configuration, the first linear member 46 can be sent out or pulled back by rotating the first rotating member 42 and the second rotating member 44 in mutually different directions. Note that a configuration may be adopted in which the first rotating member 42 winds up the first linear member 46 in a left-handed manner, and the second rotating member 44 winds up the first linear member 46 in a right-handed manner. Although not shown, the configurations of the third rotating member 52, the fourth rotating member 54, and the second linear member 56 are also similar.

Here, as shown in FIGS. 5 to 7, when the first gear train 104 and the second gear train 106 are compared, the second gear train 106 has one more gear than the first gear train 104. Therefore, for example, when the torque from the drive motor M2 is transmitted to the first sun gear 64 and the third sun gear 74 in the forward direction, it is transmitted to the second sun gear 84 and the fourth sun gear 94 in the reverse direction. It turns out. That is, the torque from drive motor M2 is transmitted to both the combinations of first sun gear 64, third sun gear 74, and second sun gear 84, and fourth sun gear 94 in different directions. Note that the first to fourth rotating members 42, 44, 52, and 54 are configured to rotate at the same speed by the torque from the drive motor M2. Therefore, when the drive motor M2 is driven in one direction, the first linear member 46 and the second linear member 56 can be sent out, and when the drive motor M2 is driven in the other direction, the first linear member 46 and the second linear member 56 can be sent out. The member 46 and the second linear member 56 can be pulled back.

The first linear member 46 and the second linear member 56 are fed out by the drive motor M2 when the arm portion 20 extends, as will be described later. is delivered at an amount corresponding to the amount of extension of the arm section 20. On the other hand, the first linear member 46 and the second linear member 56 are pulled back by the drive motor M2 when the arm portion 20 contracts, as will be described later, and the first linear member 46 and the second linear member 56 are pulled back. The member 56 is pulled back by an amount corresponding to the amount of contraction of the arm portion 20.

Note that the winding direction of the first linear member 46 with respect to the first rotating member 42 and the second rotating member 44 and the winding direction of the second linear member 56 with respect to the third rotating member 52 and the fourth rotating member 54 are set in the same direction. It is also possible to have such a configuration. In this case, the configuration may be such that the torque from the drive motor M2 is transmitted in the same direction to both the combinations of the first sun gear 64, the third sun gear 74, and the second sun gear 84 and the fourth sun gear 94. By doing so, when the drive motor M2 is driven in one direction, the first linear member 46 and the second linear member 56 can be sent out, and when the drive motor M2 is driven in the other direction, the first linear member 46 and the second linear member 56 can be sent out. The linear member 46 and the second linear member 56 can be pulled back. In short, the winding directions of the first and second linear members 46, 56 with respect to the first to fourth rotating members 42, 44, 52, 54 may have various combinations, but depending on the torque of the drive motor M2, The fourth rotating members 42, 44, 52, 54 are rotated, and the first and second linear members 46, 56 are sent out or pulled back by an amount of sending out or pulling back according to the amount of extension or contraction of the arm portion 20. Just do it like this.

Although it is possible to have a plurality of drive motors M2 corresponding to the first to fourth planetary gear mechanisms 62, 82, 72, and 92, by adopting the configuration of this embodiment, one drive motor M2 can be used. Since the first linear member 46 and the second linear member 56 can be sent out or pulled back, manufacturing costs can be reduced and the robot arm device 100 can be made more compact. Note that the first to fourth planetary gear mechanisms 62, 82, 72, and 92 may be differential gear mechanisms.

The first linear member 46 and the second linear member 56 are also configured to be sent out and pulled back by the first differential motor M3 and the second differential motor M4 (see FIG. 1). As shown in FIG. 8, the torque from the first differential motor M3 is transmitted to the first differential planetary gear mechanism 122 and the second differential planetary gear mechanism 132 via the first differential gear train 112. . The first differential planetary gear mechanism 122 includes a first differential sun gear 124, a first differential planetary gear 126, and a first differential ring gear 128, each of which is rotatably provided. The first differential ring gear 128 includes gears on the inner circumferential side and the outer circumferential side, and the gear on the inner circumferential side meshes with the first differential planetary gear 126. Similarly, the second differential planetary gear mechanism 132 is configured such that a second differential sun gear 134, a second differential planetary gear 136, and a second differential ring gear 138 are each rotatably provided. The second differential ring gear 138 includes gears on the inner circumferential side and the outer circumferential side, and the gear on the inner circumferential side meshes with the second differential planetary gear 136.

Torque from the first differential motor M3 is transmitted from the first differential gear train 112 to the first differential sun gear 124 of the first differential planetary gear mechanism 122 and the second differential sun gear 134 of the second differential planetary gear mechanism 132. is transmitted to cause the first differential planet gear 126 to revolve relative to the first differential sun gear 124 and the second differential planet gear 136 to revolve relative to the second differential sun gear 134, respectively. Then, the rotational torque of the first differential planetary gear 126 is transmitted to the first differential torque output gear 142, and the rotational torque of the second differential planetary gear 136 is transmitted to the second differential torque output gear 144. At this time, the first differential torque output gear 142 and the second differential torque output gear 144 are configured to rotate at the same speed and in the same direction.

The torque transmitted to the first differential torque output gear 142 is transmitted to a gear on the outer circumferential side of the first ring gear 68 of the first planetary gear mechanism 62 and a gear on the outer circumferential side of the second ring gear 88 of the second planetary gear mechanism 82. is transmitted to rotate the first ring gear 68 and the second ring gear 88 at the same speed and in the same direction. Further, the torque transmitted to the second differential torque output gear 144 is transmitted to the outer peripheral gear of the third ring gear 78 of the third planetary gear mechanism 72 and the outer peripheral side of the fourth ring gear 98 of the fourth planetary gear mechanism 92. The rotation of the first ring gear 68 and the second ring gear 88 due to the torque from the first differential torque output gear 142 causes the third ring gear 78 and the fourth ring gear 98 to rotate at the same speed. direction.

With this configuration, the first to fourth planetary gears 66, 86, 76, 96 of the first to fourth planetary gear mechanisms 62, 82, 72, 92 are caused to revolve in the same direction by the torque of the first differential motor M3. Can provide torque. Further, when the first to fourth planetary gears 66, 86, 76, 96 are revolving by the drive motor M2, the first planetary gear 66 and the third planetary gear are rotated depending on the rotation direction of the first differential motor M3. 76 and increase the revolution speeds of the second planetary gear 86 and the fourth planetary gear 96, or increase the revolution speed of the first planetary gear 66 and the third planetary gear 76, and The revolution speeds of the planetary gear 86 and the fourth planetary gear 96 can be reduced.

As a result, the first rotating member 42 and the third rotating member 52 are rotated in the direction in which the first linear member 46 and the second linear member 56 are sent out, and the first linear member 46 and the second linear member 56 are rotated. The second rotating member 44 and the fourth rotating member 54 are rotated in the pulling back direction, the first linear member 46 and the second linear member 56 are sent out and pulled back, and the first pulley 34 and the second pulley 36 are moved in one direction. It can be rotated to Alternatively, the first rotating member 42 and the third rotating member 52 are rotated in the direction in which the first linear member 46 and the second linear member 56 are pulled back, and the first linear member 46 and the second linear member 56 are sent. The second rotating member 44 and the fourth rotating member 54 are rotated in the extending direction, the first linear member 46 and the second linear member 56 are sent out and pulled back, and the first pulley 34 and the second pulley 36 are moved in the other direction. It can be rotated. In this way, the hand mounting portion 38 can be rotated in the rotational direction of the first pulley 34 and the second pulley 36. Therefore, since there is no need to provide a motor for rotating the hand attachment portion 38 on the wrist portion 30, an unbalanced load is less likely to be applied to the arm portion 20, and the arm portion 20 is compact. Moreover, the hand portion attachment portion 38 can be reliably rotated by rotating the first pulley 34 and the second pulley 36, respectively.

When the winding direction of the first linear member 46 with respect to the first rotating member 42 and the second rotating member 44 and the winding direction of the second linear member 56 with respect to the third rotating member 52 and the fourth rotating member 54 are made in the same direction , the first ring gear 68 and the second ring gear 88 are rotated in opposite directions at the same speed, and the third ring gear 78 and the fourth ring gear 98 are also rotated in opposite directions at the same speed by the torque from the first differential motor M3. so that the combinations of the first ring gear 68, the second ring gear 88, the third ring gear 78, and the fourth ring gear 98 are rotated in the same direction, and the first pulley 34 and the second pulley 36 are rotated in the same direction. It should be configured as follows. Furthermore, as described above, the winding directions of the first and second linear members 46, 56 with respect to the first to fourth rotating members 42, 44, 52, 54 may be variously combined; The first to fourth rotating members 42, 44, 52, 54 are rotated by the torque of the motor M3, the first and second linear members 46, 56 are sent out and pulled back, and the first pulley 34 and the second pulley 36 are moved. What is necessary is just to configure it so that it rotates in the same direction.

As shown in FIG. 9, the torque from the second differential motor M4 is applied to the outer circumferential gear of the first differential ring gear 128 of the first differential planetary gear mechanism 122 via the second differential gear train 114. is transmitted to. On the other hand, the torque from the second differential motor M4 is transmitted to the gear on the outer peripheral side of the second differential ring gear 138 of the second differential planetary gear mechanism 132 via the third differential gear train 116. . Here, the first differential gear train 114 and the third differential gear train 116 are configured to transmit rotation in opposite directions to the first differential ring gear 128 and the second differential ring gear 138. .

Torque from second differential gear train 114 causes first differential planetary gear 126 to revolve in one direction relative to first differential sun gear 124 . On the other hand, the torque from the third differential gear train 116 causes the second differential planetary gear 136 to revolve in the other direction with respect to the second differential sun gear 134. The revolving torque of the first differential planetary gear 126 is transmitted to the first differential torque output gear 142, and the revolving torque of the second differential planetary gear 136 is transmitted to the second differential torque output gear 144. It is configured as follows. Therefore, the first differential torque output gear 142 and the second differential torque output gear 144 rotate at the same speed in opposite directions.

As described above, the torque transmitted to the first differential torque output gear 142 is transmitted to the outer gear of the first ring gear 68 of the first planetary gear mechanism 62 and the second ring gear 88 of the second planetary gear mechanism 82. The first ring gear 68 and the second ring gear 88 are rotated at the same speed and in the same direction. Further, the torque transmitted to the second differential torque output gear 144 is transmitted to the outer peripheral gear of the third ring gear 78 of the third planetary gear mechanism 72 and the outer peripheral side of the fourth ring gear 98 of the fourth planetary gear mechanism 92. The rotation of the first ring gear 68 and the second ring gear 88 due to the torque from the first differential torque output gear 142 causes the third ring gear 78 and the fourth ring gear 98 to rotate at the same speed. direction.

Thus, with this configuration, the combinations of the first ring gear 68, the second ring gear 88, the third ring gear 78, and the fourth ring gear 98 are rotated at the same speed in opposite directions by the torque from the second differential motor M4. can be done. Note that when the first to fourth planetary gears 66, 86, 76, 96 are revolving by the drive motor M2, the first planetary gear 66 and the fourth planetary gear are rotated depending on the rotation direction of the second differential motor M4. 96 and increase the revolution speeds of the second planetary gear 86 and the third planetary gear 76, or increase the revolution speed of the first planetary gear 66 and the fourth planetary gear 96, and The revolution speeds of the planetary gear 86 and the third planetary gear 76 can be reduced.

As a result, the first rotating member 42 and the fourth rotating member 54 are rotated in the direction in which the first linear member 46 and the second linear member 56 are sent out, and the first linear member 46 and the second linear member 56 are rotated. The second rotating member 44 and the third rotating member 52 are rotated in the pulling back direction, the first linear member 46 and the second linear member 56 are sent out and pulled back, and the first pulley 34 and the second pulley 36 are moved opposite each other. It can be rotated in any direction. Alternatively, the first rotating member 42 and the fourth rotating member 54 are rotated in the direction of pulling back the first linear member 46 and the second linear member 56, and the first linear member 46 and the second linear member 56 are sent. The second rotating member 44 and the third rotating member 52 are rotated in the extending direction, the first linear member 46 and the second linear member 56 are sent out and pulled back, and the first pulley 34 and the second pulley 36 are moved in opposite directions. It can be rotated to In this way, the hand mounting portion 38 can be rotated about the second mounting shaft 31 which is an axis perpendicular to the axes of the first bevel gear 35 and the second bevel gear 37. In this manner, in the robot arm device 100, the hand mounting portion 38 can be rotated around two orthogonal axes, so that the hand mounting portion 38 and, by extension, the hand portion can be freely rotated. Can be done. Note that the first differential motor M3 and the second differential motor M4 may be driven individually or simultaneously.

When the winding direction of the first linear member 46 with respect to the first rotating member 42 and the second rotating member 44 and the winding direction of the second linear member 56 with respect to the third rotating member 52 and the fourth rotating member 54 are made in the same direction , the torque from the second differential motor M4 rotates the first ring gear 68 and the second ring gear 88 at the same speed in opposite directions, and the third ring gear 78 and the fourth ring gear 98 also rotate at the same speed in opposite directions. to rotate the combinations of the first ring gear 68, second ring gear 88, third ring gear 78, and fourth ring gear 98 in opposite directions, and to rotate the first pulley 34 and second pulley 36 in opposite directions. It should be configured as follows. Furthermore, as described above, the winding directions of the first and second linear members 46, 56 with respect to the first to fourth rotating members 42, 44, 52, 54 may be variously combined; The first to fourth rotating members 42, 44, 52, 54 are rotated by the torque of the motor M4, the first and second linear members 46, 56 are sent out and pulled back, and the first pulley 34 and the second pulley 36 are moved. What is necessary is just to configure it so that it rotates in the opposite direction.

In addition, by providing a plurality of first differential motors M3 and a plurality of second differential motors M4 corresponding to the first to fourth ring gears 68, 88, 78, and 98, and controlling each of them, the first to fourth differential motors It is also possible to configure the rotating members 42, 44, 52, 54 to rotate. However, like the robot arm device 100, the torques of the first differential motor M3 and the second differential motor M4 are transmitted from the first to the second differential planetary gear mechanism 122 and the second differential planetary gear mechanism 132. If the configuration is such that the power is transmitted to the four rotating members 42, 44, 52, and 54, the required number of first differential motors M3 and second differential motors M4 can be reduced, so manufacturing costs can be reduced. The robot arm device 100 can be made compact. Note that the first and second differential planetary gear mechanisms 122 and 132 may be differential gear mechanisms.

As described above, in the robot arm device 100, the first rotating member 42 is connected to the first planetary gear 66, the first sun gear 64 is connected to the drive motor M2, and the first ring gear 68 is connected to the first differential motor M3 and the second differential motor M2. The configuration is such that torque is transmitted from the differential motor M4. In this configuration, torque is transmitted to the first rotating member 42 from either the first sun gear 64, the first planetary gear 66, or the first ring gear 68, and the torque from the drive motor M2 is transmitted to the first rotating member 42. Torque is transmitted to any of the first sun gear 64, first planet gear 66, or first ring gear 68 that is not the first sun gear 64, first planet gear 66, or first ring gear 68 that transmits the torque, and the first difference is The torque from the dynamic motor M3 and the second differential motor M4 is not the first sun gear 64, the first planetary gear 66, or the first ring gear 68 that transmits torque to the first rotating member 42, and the torque from the drive motor M2 Torque is transmitted to any of the first sun gear 64, first planet gear 66, or first ring gear 68 other than the first sun gear 64, first planet gear 66, or first ring gear 68 to which the torque is transmitted. It should be configured as follows. The same applies to the second to fourth rotating members 44, 52, and 54.

As shown in FIG. 10, the arm portion 20 includes a first plate 22, a second plate 24, a third plate 26, and a fourth plate 28. The base body 10 is connected to the first plate 22 side, and the wrist portion 30 is connected to the fourth plate 28 side. The first plate 22 includes a hollow first nut member 21a that is threaded on the inner diameter side. The first nut member 21a is rotatably provided and configured so that torque from the drive motor M2 is transmitted to the first nut member 21a. On the other hand, the second plate 24 includes a rod-shaped first screw member 23a that is screwed into the inner diameter side screw of the first nut member 21a. Therefore, when the first nut member 21a is rotated by the torque of the drive motor M2, the second plate 24 moves away from or approaches the first plate 22 depending on the direction of rotation.

Further, the second plate 24 includes a hollow second nut member 21b having a thread provided on the inner diameter side. On the other hand, the third plate 26 includes a rod-shaped second screw member 23b that is screwed into the inner diameter side screw of the second nut member 21b. Further, the third plate 26 includes a hollow third nut member 21c provided with a thread on the inner diameter side, and the fourth plate 28 has a rod-shaped third nut member 21c that is screwed into the thread on the inner diameter side of the third nut member 21c. It has three screw members 23c. Torque from the drive motor M2 is transmitted from the first nut member 21a to the second nut member 21b through the first rotation transmission nut 25a and the first rotation transmission shaft 27a which is keyed to the first rotation transmission nut 25a. . Similarly, the torque from the first rotation transmission shaft 27a is also transmitted to the third nut member 21c through the second rotation transmission nut 25b and the second rotation transmission shaft 27b keyed to the second rotation transmission nut 25b. . Therefore, by driving the drive motor M2, it is possible to move the third plate 26 away from or approach the second plate 24 and the fourth plate 28 from the third plate 26, respectively. Note that a plurality of combinations of the first to third nut members 21a, 21b, 21c and the first to third screw members 23a, 23b, 23c may be provided.

If the arm section 20 is configured to extend and contract using the torque from the drive motor M2 in this way, it is not necessary to provide a separate motor for extending and contracting the arm section 20. Further, since there is no need for a space for storing the first frame row and the second frame row as shown in Patent Document 2, the robot arm device 100 can be made relatively compact.

As described above, according to the present invention, it is possible to provide a robot arm device that is compact, in which an unbalanced load is not easily applied to the arm portion, and that allows the wrist portion to freely rotate.

10 base body 20 arm part 21a first nut member 21b second nut member 22 first plate 23a first screw member 23b second nut member 24 second plate 26 third plate 30 wrist part 32 base part 34 first pulley 35 first umbrella Gear 36 Second pulley 37 Second bevel gear 38 Hand part attachment part 39 Hand part bevel gear 42 First rotating member 44 Second rotating member 46 First linear member 52 Third rotating member 54 Fourth rotating member 56 Second line shaped member 62 first planetary gear mechanism 64 first sun gear 66 first planetary gear 68 first ring gear 72 third planetary gear mechanism 74 third sun gear 76 third planetary gear 78 third ring gear 82 second planetary gear mechanism 84 Second sun gear 86 Second planet gear 88 Second ring gear 92 Fourth planetary gear mechanism 94 Fourth sun gear 96 Fourth planet gear 98 Fourth ring gear 100 Robot arm device M2 Drive motor M3 First differential motor M4 Second differential motor

Claims (7)

A robot arm device having a base body, an extendable arm portion connected to the base body, and a wrist portion connected to a distal end side of the arm portion, the robot arm device comprising:
The wrist portion includes a base, a first pulley rotatably provided on the base, and a hand attachment portion connected to the first pulley,
The base body includes at least one drive motor, at least one first differential motor, a first rotating member and a second rotating member for feeding or retracting the first linear member, and the first and second rotating members. First and second planetary gear mechanisms respectively configured of rotatable first and second sun gears, first and second planetary gears, and first and second ring gears corresponding to the rotating member,
the first linear member is hung on the first pulley;
The first rotating member is configured such that torque is transmitted from any one of the first sun gear, first planetary gear, or first ring gear,
The second rotating member is configured such that torque is transmitted from either the second sun gear, the second planetary gear, or the second ring gear,
The torque from the drive motor is transmitted to the first and second rotating members other than the first and second sun gears, first and second planetary gears, or first and second ring gears that transmit torque to the first and second rotating members. configured to be transmitted to any one of the sun gear, the first planet gear, or the first ring gear and the second sun gear, the second planet gear, or the second ring gear,
The torque from the first differential motor is not transmitted to the first and second sun gears, first and second planetary gears, or first and second ring gears that transmit torque to the first and second rotating members. , and the first sun gear, first planetary gear, or third ring gear is not the first and second sun gears, first and second planetary gears, or first and second ring gears to which torque is transmitted from the drive motor. configured to be transmitted to either one of the first ring gear and the second sun gear, second planetary gear, or second ring gear,
When the arm part extends, the first and second rotating members are rotated by the torque from the drive motor, and the first linear member is delivered at a delivery amount corresponding to the amount of extension of the arm part,
When the arm part contracts, the first and second rotating members are rotated by the torque from the drive motor, and the first linear member is pulled back by an amount corresponding to the amount of contraction of the arm part,
The torque from the first differential motor is configured to rotate the first and second rotating members, send out and pull back the first linear member, and rotate the first pulley. Characterized by
robot arm device. the first pulley includes a first bevel gear;
The hand part mounting part is rotatably provided around an axis perpendicular to the axis of the first bevel gear and includes a hand part bevel gear,
2. The robot arm device according to claim 1, wherein the first pulley and the hand mounting portion are connected by meshing between the first bevel gear and the hand bevel gear. The wrist portion further includes a second pulley rotatably provided on the base portion,
The second pulley includes a second bevel gear having an axis parallel to the axis of the first bevel gear and meshing with the hand part bevel gear,
The base body further includes a third rotating member and a fourth rotating member for sending out or pulling back the second linear member, and rotatable third and fourth rotating members corresponding to the third and fourth rotating members. Equipped with third and fourth planetary gear mechanisms each consisting of a sun gear, third and fourth planetary gears, and third and fourth ring gears,
the second linear member is hung on the second pulley,
The third rotating member is configured such that torque is transmitted from any one of the third sun gear, third planetary gear, or third ring gear,
The fourth rotating member is configured such that torque is transmitted from any one of the fourth sun gear, fourth planetary gear, or fourth ring gear,
The torque from the drive motor is not the third and fourth sun gears, third and fourth planetary gears, or third and fourth ring gears that transmit torque to the third and fourth rotating members. configured to be transmitted to any one of a third sun gear, a third planetary gear, or a third ring gear and to any one of the fourth sun gear, fourth planetary gear, or fourth ring gear,
The torque from the first differential motor further transmits torque to the third and fourth rotating members, such as the third and fourth sun gears, third and fourth planetary gears, or third and fourth ring gears. and the third sun gear, the third planetary gear, which is not the third and fourth sun gears, the third and fourth planetary gears, or the third and fourth ring gears to which torque is transmitted from the drive motor, or configured to be transmitted to any of the third ring gear and any of the fourth sun gear, fourth planetary gear, or fourth ring gear,
When the arm section extends, the third and fourth rotating members are rotated by the torque from the drive motor, and the second linear member is sent out at a delivery amount corresponding to the amount of extension of the arm section;
When the arm part contracts, the third and fourth rotating members are rotated by the torque from the drive motor, and the second linear member is pulled back by an amount corresponding to the amount of contraction of the arm part,
Torque from the first differential motor rotates the third and fourth rotating members, sends out and pulls back the second linear member, and rotates the second pulley in the same direction as the first pulley. The robot arm device according to claim 2, wherein the robot arm device is configured as follows. The hand part attachment part is further provided rotatably about an axis parallel to the axis of the first bevel gear,
the base further comprising at least one second differential motor;
The torque from the second differential motor is not transmitted to the first to fourth sun gears, first to fourth planetary gears, or first to fourth ring gears that transmit torque to the first to fourth rotating members. , and the first sun gear, first planetary gear, or third ring gear is not the first to fourth sun gear, first to fourth planetary gear, or first to fourth ring gear to which torque is transmitted from the drive motor. any one of the first ring gear, the second sun gear, the second planet gear, or the second ring gear, the third sun gear, the third planet gear, or the third ring gear, and the fourth sun gear , a fourth planetary gear, or a fourth ring gear,
The first to fourth rotating members are each rotated by the torque from the second differential motor, the first and second linear members are sent out or pulled back, and the first pulley and the second pulley are moved differently from each other. 4. The robot arm device of claim 3, wherein the robot arm device is configured to rotate in a direction. The robot arm device according to any one of claims 1 to 4, wherein the arm section is configured to expand and contract using torque from the drive motor. The arm portion includes a first plate and a second plate between the base body and the wrist portion,
The first plate includes a hollow first nut member having an inner diameter thread and configured to be rotated by torque from the drive motor;
The second plate includes a rod-shaped first threaded member that is threaded into the thread on the inner diameter side of the first nut member,
6. The robot arm device according to claim 5, wherein the second plate moves away from or approaches the first plate when the first nut member rotates. The arm further includes a third plate between the wrist and the second plate,
The second plate includes a hollow second nut member configured to be rotated by torque from the drive motor and has a thread on the inner diameter side,
The third plate includes a rod-shaped second threaded member that is threaded into the thread on the inner diameter side of the second nut member,
7. The robot arm device according to claim 6, wherein the third plate moves away from or approaches the second plate as the second nut member rotates.

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