JP6940544B2 - Rotating axis module and articulated robot - Google Patents

Description

The present invention relates to a rotary shaft module and an articulated robot equipped with such a rotary shaft module.

In order to transmit rotational power from an electric motor to, for example, a robot arm of an industrial robot, a gear reduction mechanism composed of a plurality of gears has been conventionally used. The gear reduction mechanism disclosed in Patent Document 1 relates to a rotational power source, for example, an input gear connected to an electric motor, a rotated drive body, for example, an output gear connected to a robot arm, and an input gear and an output gear. Includes a mating intermediate gear assembly. The intermediate gear assembly of Patent Document 1 is mounted on the same mounting surface as the mounting surface of the rotational power source and the driven drive body.

Further, Patent Document 2 discloses a reduction mechanism using a plurality of two-stage spur gears. A plurality of two-stage spur gears are juxtaposed with each other in a straight line between the input gear and the output gear. Therefore, when such a deceleration mechanism is arranged at the wrist tip of the robot, the wrist tip can be miniaturized in the thickness (height) direction and the width direction.

Japanese Unexamined Patent Publication No. 9-119486 Japanese Unexamined Patent Publication No. 2014-612

However, in Patent Document 2, since a plurality of two-stage spur gears are juxtaposed with each other in a straight line between the input gear and the output gear, the dimension of the reduction gear mechanism in the juxtaposed direction (arm longitudinal direction) becomes large.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a rotary shaft module that can be miniaturized.

According to the first invention to achieve the above-mentioned object, the input shaft to which the drive motor is connected, the output shaft, the output shaft flange connected to the output shaft, and the output shaft flange are coupled to each other. A parallel shaft gear, a reduction gear outer peripheral case rotatably supported by the output shaft flange, a two-stage gear train including at least two two-stage gears arranged in the reduction gear outer peripheral case, and a drive motor. A transmission gear that transmits power to the two-stage gear train is provided, and the parallel shaft gear and the small gear of one of the at least two two-stage gears are engaged with each other, and at least the small gear of the two-stage gear is engaged. The transmission gear is engaged with the large gear of the other two-stage gear of the two two-stage gears, and the at least two two-stage gears and the transmission gear surround the output shaft. Provided is a rotary shaft module that is located in the space between the inner surface of the speed reducer outer case and the output shaft.
According to the second invention, in the first invention, each of the at least two two-stage gears is supported by a support bearing and a support member, and the support member is a mounting flange to which the drive motor is mounted. Is fixed to.
According to the third invention, in the first or second invention, the output shaft is formed with a hollow hole into which a striatum is to be inserted.
According to the fourth invention, in any one of the first to third inventions, the parallel shaft gear is an internal gear.
According to the fifth invention, in any one of the first to fourth inventions, the inner ring side further includes a bearing coupled to the output shaft flange, and the bearing is an angular back surface combination bearing.
According to the sixth invention, in any of the second to fifth inventions, at least one of the supporting members of the two-stage gear is supported on both the small gear side and the large gear side. bottom.
According to the seventh invention, in any of the second to sixth inventions, the supporting members of the at least two two-stage gears are connected to each other by a reinforcing member.
According to the eighth invention, in any of the second to seventh inventions, the supporting bearing of at least one of the at least two two-stage gears includes a needle roller bearing.
According to the ninth invention, in any of the second to eighth inventions, the supporting bearing of at least one of the at least two two-stage gears includes a ball bearing.
According to the tenth invention, in any one of the first to ninth inventions, the reduction ratio between the parallel shaft gear and the small gear of the one two-stage gear is the large of the one two-stage gear. It was set to be larger than the reduction ratio between the gear and the small gear of the other two-stage gear.
According to the eleventh invention, in any one of the first to tenth inventions, the at least two two-stage gears include a shaft portion extending from the end face of the large gear, and the two-stage gear is cantilevered. The shaft portion is supported so as to support it.
According to the twelfth invention, in any one of the first to eleventh inventions, at least one lip of the oil seal used in the rotary shaft module is the minimum necessary tension as long as the sealing function is not impaired. Have power.
According to the thirteenth invention, in any one of the first to twelfth inventions, the drive motor is mounted on the mounting surface so that the rotation axis of the drive motor is parallel to the mounting surface of the output shaft flange. Can be installed.
According to the fourteenth invention, an articulated robot including at least one rotation axis module according to any one of the first to thirteenth is provided.

In the first invention, since at least two two-stage gears and transmission gears are arranged around the output shaft so as to surround the output shaft, the rotary shaft module can be miniaturized. Further, since the rotary shaft module is composed of only parallel shaft gears having high reverse efficiency, the efficiency of transmitting external force from the output arm side to the input motor side can be improved.
In the second invention, the two-stage gear can be stably fixed to the mounting flange.
In the third invention, a striatum such as a drive cable or an air tube can be inserted into the hollow hole. Therefore, when the rotary shaft module is mounted on the robot arm, the striatum can be easily stored in the robot arm, and the striatum can be prevented from being exposed.
In the fourth invention, when the parallel shaft gear is an internal gear, the reduction ratio can be increased as compared with the case where the parallel shaft gear is an external gear.
In the fifth invention, when the bearing is an angular rear combination bearing, it is possible to simultaneously receive a moment acting on the output shaft and a radial load acting on the parallel shaft spur gear.
In the sixth invention, since the two-stage gear is supported by both sides, the two-stage gear can be stably supported by the supporting member even if a large tilting moment acts. Therefore, the reduction ratio of the two-stage gear can be increased.
In the seventh invention, since the supporting members of the adjacent two-stage gears are connected and reinforced by a reinforcing member, for example, a beam member, a structure that is more resistant to falling can be obtained.
In the eighth invention, the diameter of the small gear can be reduced by using the needle-shaped roller bearing as the supporting bearing for the small gear of the two-stage gear. Therefore, the reduction ratio of the two-stage gear can be increased.
In the ninth invention, when a ball bearing, for example, a deep groove ball bearing, is used, a small thrust load, for example, a thrust load due to its own weight acting on the two-stage gear can be supported.
In the tenth invention, assuming that the total reduction ratio is the same, the diameter of the large gear of one of the two-stage gears is made relatively small, and as a result, the reduction gear outer peripheral case is made smaller. Can be done.
In the eleventh invention, the small gear of the two-stage gear can be further reduced by cantilevering the shaft portion extending from the end face of the two-stage gear with a bearing. As a result, the reduction ratio per meshing portion can be further increased.
The rotational friction of the oil seal can reduce the efficiency of external force transmission from the output shaft side to the input shaft side. In the twelfth invention, since the lip having the minimum necessary tension force is used without impairing the sealing function, the minimum rotational friction and therefore the minimum friction loss can be obtained. Therefore, the transmission efficiency can be further improved.
In the thirteenth invention, the length of the rotary shaft module in the output shaft direction can be shortened by arranging the drive motor so that the rotary axis of the drive motor is parallel to the mounting surface of the output shaft flange.
In the fourteenth invention, the rotating shaft module and the link member can be combined to easily form various forms of articulated robots.

These objectives, features and advantages as well as other objectives, features and advantages of the present invention will become clearer from the detailed description of typical embodiments of the invention shown in the accompanying drawings.

It is a side view of the rotary shaft module of this invention. It is sectional drawing seen along the line AA of FIG. 1A. It is an end view of the rotary shaft module shown in FIG. 1A. It is a partial decomposition perspective view of the rotary shaft module based on the 1st Embodiment of this invention. It is sectional drawing seen along the line BB of FIG. 1B. It is sectional drawing seen along the line CC of FIG. 1B. It is a partially transparent end view of the rotary shaft module shown in FIG. 1A. It is sectional drawing of the rotary shaft module including a planetary gear reducer. It is a partial decomposition perspective view of the rotary shaft module based on the 2nd Embodiment of this invention. It is a front view of one two-step gear. It is sectional drawing of one two-step gear. It is the first partial perspective view of the rotary shaft module. It is the 2nd partial perspective view of the rotary shaft module. It is a third partial perspective view of the rotary shaft module. It is a partially transparent end view of a rotating shaft module. It is the other partial transmission end view of a rotating shaft module. It is sectional drawing of a two-step gear. It is a partial cross-sectional view of a rotating shaft module. It is a partially enlarged view which shows a part of FIG. 11A. It is sectional drawing of the rotary shaft module based on another embodiment of this invention. It is a figure which shows the robot which uses the rotary shaft module of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Similar members are designated by the same reference numerals in the drawings below. These drawings have been scaled accordingly for ease of understanding.
FIG. 1A is a side view of the rotary shaft module of the present invention. Further, FIG. 1B is a cross-sectional view taken along the line AA of FIG. 1A, and FIG. 1C is an end view of the rotary shaft module shown in FIG. 1A.

As shown in these drawings, the rotary shaft module 10 has a substantially cylindrical shape covered with a speed reducer outer peripheral case 13. However, the rotary shaft module 10 may have a shape other than the cylindrical shape. The input shaft 11 is arranged on one end face of the rotary shaft module 10, and the output shaft 12 is arranged on the other end face.

Further, the end surface on the input shaft 11 side is a mounting flange 16, and a drive motor 90 that transmits a rotational force to the input shaft 11 is mounted on the mounting flange 16. Further, the end face on the output shaft 12 side is configured as an output shaft flange 15 connected to the output shaft 12.

FIG. 2 is a partially exploded perspective view of a rotary shaft module based on the first embodiment of the present invention. 3A is a cross-sectional view taken along line BB of FIG. 1B, and FIG. 3B is a cross-sectional view taken along line CC of FIG. 1B. As shown in FIGS. 2 and 3A, an external gear 17 as a parallel shaft gear is coupled to the output shaft flange 15. The external gear 17 is, for example, a spur gear or an oblique gear.

Further, the external gear 17 is engaged with the small gear 21a of the first two-stage gear 21. As can be seen from FIGS. 2 and 3B, the small gear 22a of the second two-stage gear 22 is engaged with the large gear 21b of the first two-stage gear 21. Further, the small gear 23a of the third two-stage gear 23 is engaged with the large gear 22b of the second two-stage gear 22.

Further, the small gear 24a of the fourth two-stage gear 24 is engaged with the large gear 23b of the third two-stage gear 23. Finally, the large gear 24b of the fourth two-stage gear 24 is engaged with the transmission gear 91 that transmits the power of the drive motor 90. In FIG. 2, the gears are engaged with each other at five positions of the first to fourth two-stage gears 21 to 24 and the transmission gear 91, and therefore, FIG. 2 shows a five-stage reduction mechanism.

FIG. 4 is a partially transparent end view of the rotary shaft module shown in FIG. 1A. As can be seen with reference to FIGS. 1B and 4, the space between the inner surface of the reduction gear outer peripheral case 13 and the output shaft 12 so that the plurality of two-stage gears 21 to 24 and the transmission gear 91 surround the output shaft 12. Is located in. That is, in the present invention, the plurality of two-stage gears 21 to 24 and the transmission gear 91 are not juxtaposed in a straight line. In the present invention, since the plurality of two-stage gears 21 to 24 and the transmission gear 91 surround the output shaft 12, it can be seen that the rotary shaft module 10 can be miniaturized. The number of two-stage gears may be an integer of 2 or more.

Further, in the rotary shaft module 10 of the present invention, the rotary shaft module 10 is composed of only two-stage gears 21 to 24 and an external gear 17. These gears are parallel shaft gears and have high reverse efficiency. Therefore, when the rotary shaft module 10 is applied to a robot, particularly a human-cooperative robot, as will be described later, the transmission efficiency in which an external force is transmitted from the output arm side of the robot to the input motor side can be improved.

That is, for example, when a human collides with a robot, the force is transmitted to the input motor side with high sensitivity. Then, by utilizing such a force, a highly sensitive contact stop function can be realized in the human cooperative robot. For the same reason, it becomes easy to realize a read-through function in which the operator manually teaches the teaching position to the robot.

Furthermore, since it is easy to transmit an external force to the input unit of the rotary shaft module 10, various sensors required for the contact stop function and the read-through function can be reduced or replaced with an inexpensive sensor having low resolution. There is sex. Therefore, it can be seen that the rotary shaft module 10 can be manufactured at a lower cost than in the past.

As can be seen from FIG. 1B, a plurality of two-stage gears 21 to 24 are not arranged in the space on the right side in the speed reducer outer peripheral case 13. A plurality of two-stage gears may be further arranged so that the surplus space on the right side is eliminated, and in that case, the total reduction ratio of the rotary shaft module 10 can be increased. Further, the shape may be such that the outer peripheral case 13 of the speed reducer is partially recessed so as to eliminate the surplus space. In this case, the weight of the outer peripheral case 13 of the speed reducer is further reduced and the lubricating oil sealed inside the speed reducer is further reduced. It is also possible to reduce the weight of the rotating shaft module as a whole.

Referring to FIG. 2 again, the outer peripheral portion of the output shaft flange 15 is coupled to the inner ring side of the large bearings 18a and 18b, and the speed reducer outer peripheral case 13 is coupled to the outer ring side of the large bearings 18a and 18b. Further, as described above, the external gear 17 is coupled to the vicinity of the center of the output shaft flange 15. Therefore, the large bearings 18a and 18b receive a force acting on the output shaft 12 from the outside and a force from the small gear 21a of the first two-stage gear 21.

The large bearings 18a and 18b are preferably angular back surface combination bearings having a relatively large size and low rotational friction. When the large bearings 18a and 18b as the angular back combination bearings are used, the moment acting on the output shaft 12 and the radial load acting on the parallel shaft spur gear 17 can be received at the same time. Further, it is possible to minimize a decrease in the efficiency of external force transmission from the output shaft side to the input shaft side. Further, since the angular back combination bearing is incorporated into the rotary shaft module 10 as it is, there is an advantage that the preload adjustment work is not required when manufacturing the rotary shaft module 10.

FIG. 5 is a cross-sectional view of a rotary shaft module including a planetary gear reducer. The rotary shaft module shown in FIG. 5 includes a first planetary gear reduction mechanism 30a and a second planetary gear reduction mechanism 30b. Each planetary gear reduction mechanism 30a, 30b includes sun gears 31a, 31b, internal gears 33a, 33b, and a plurality of planetary gears 32a, 32b that engage the sun gears 31a, 31b and internal gears 33a, 33b. ..

In FIG. 5, the sun gear 31a of the planetary gear reduction mechanism 30a is integrated with the input shaft 11, and the output of the planetary gear reduction mechanism 30a is transmitted to the sun gear 31b of the second planet gear reduction mechanism 30b through the carrier 34. .. Further, a cross roller bearing 35 is arranged between the internal gear 33b and the output shaft flange 15.

Generally, a one-stage planetary gear reduction mechanism can transmit a large force, but cannot obtain a large reduction ratio. Therefore, in order to obtain a reduction ratio equivalent to that of the rotary shaft module 10 having the configuration shown in FIG. 2, a planetary gear reduction mechanism having three or more stages is required. As a result, the rotary shaft module using the planetary gear reduction mechanism becomes longer in the axial direction. On the other hand, the rotary shaft module 10 shown in FIG. 2 can have its axial length shorter than the axial length of the rotary shaft module using the planetary gear reduction mechanism.

Further, in the planetary gear reduction mechanism, since a plurality of planetary gears rotate around the sun gear, it is extremely difficult to adjust the backlash. On the other hand, in the rotary shaft module 10 shown in FIG. 2, the backlash can be adjusted only by adjusting the arrangement position of a specific two-stage gear.

For example, only the arrangement positions of the first two-stage gear 21, the third two-stage gear 23, and the fourth two-stage gear 24 in FIG. 4 need to be adjusted. Further, the fourth two-stage gear 24 is adjacent to the drive motor 90, and the influence of backlash can be reduced by the cumulative reduction ratio between the third two-stage gear 23 and the first two-stage gear 21. Therefore, the adjustment work of the fourth two-stage gear 24 may be omitted. As described above, it can be seen that the rotating shaft module 10 shown in FIG. 2 can adjust the backlash extremely easily.

FIG. 6 is a partially decomposed perspective view of the rotary shaft module based on the second embodiment of the present invention. As shown in FIG. 6, an internal gear 19 as a parallel shaft gear is coupled to the output shaft flange 15. The internal gear 19 is, for example, a spur gear or an oblique gear. In FIG. 6, the small gear 21a of the first two-stage gear 21 is engaged with the internal gear 19 coupled to the output shaft flange 15. Since other configurations are substantially the same as those described with reference to FIG. 2, the description will be omitted again.

Compared with the rotary shaft module 10 using the external gear 17 shown in FIG. 2, the rotary shaft module 10 shown in FIG. 6 reduces the speed between the internal gear 19 and the small gear 21a of the first two-stage gear 21. The ratio can be further increased.

Further, in FIGS. 2 and 6, a hollow hole 12a for passing a striatum such as a drive cable or an air tube is formed at the center of the output shaft 12. Therefore, when the rotary shaft module 10 is mounted on the robot arm, the striatum can be easily stored in the robot arm, and the striatum can be prevented from being exposed.

The hollow hole 12a is preferably composed of a pipe member penetrating the rotary shaft module 10. In this case, it is preferable that an O-ring is arranged between the pipe member and the output shaft flange 15 and an oil seal and a ball bearing are provided between the pipe member and the mounting flange 16. As a result, the pipe member can be supported while being sealed.

FIG. 7A is a front view of one two-stage gear, and FIG. 7B is a cross-sectional view of the two-stage gear. In these drawings, the first two-stage gear 21 is shown as an example. However, the other two-stage gears 22 to 24 may have substantially the same configuration.

As shown in FIGS. 7A and 7B, the gear support 51 includes a base 51a, a support member 51b extending vertically from the base 51a, and an arm extending from the base 51a and engaging with the tip of the support member 51b. Mainly includes the member 51c. Then, the first two-stage gear 21 is rotatably inserted into the support member 51b.

Generally, a tilting moment acts on the supporting member of the two-stage gear. In particular, a large tilting moment acts on the supporting member 51b of the first two-stage gear 21 that engages with the parallel shaft gear 17 of the output shaft 12. However, in the configurations shown in FIGS. 7A and 7B, since the two-stage gear 21 is supported by both sides, the support member 51b can stably support the two-stage gear 21 even if a large tilting moment acts. .. Therefore, the reduction ratio of the two-stage gear 21 can be increased.

As described above, the support member 51b is supported by the base 51a and the arm member 51c in a double-holding manner. Therefore, the support member 51b is hard to fall down. As can be seen from FIG. 2 and the like, the gear support portion 51 is housed in the reduction gear outer peripheral case 13 so as not to interfere with the output shaft flange 15 and the external gear 17 or the internal gear 19 coupled to the output shaft flange 15. There is. Further, as can be seen from FIG. 2 and the like, the base 51a is mounted on the mounting flange 16 of the rotary shaft module 10.

As shown in FIG. 7B, a needle-shaped roller bearing 56 is arranged between the first two-stage gear 21 and the support member 51b. Since the needle-shaped roller bearing 56 can bear the load in the radial direction, the diameter of the small gear 21a can be reduced, and the reduction ratio at one meshing portion can be increased. Therefore, it is possible to increase the reduction ratio of the two-stage gear.

When the rotary shaft module 10 itself is shaken, a force that moves the two-stage gear 21 and the like in the axial direction acts. However, such a force cannot be fully applied, and the gear support portion 51 may be damaged.

In the present invention, as shown in FIG. 7B, a ball bearing 55, for example, a deep groove ball bearing, is arranged above the small gear 21a of the first two-stage gear 21. The ball bearing 55 can bear the thrust load due to its own weight acting on the two-stage gear, for example, and therefore can bear the force for moving the two-stage gear 21 in the axial direction. Therefore, even when the rotary shaft module 10 is shaken, it is possible to prevent the gear support portion 51 from being damaged. In this case, the ball bearing 55 acts on the small gear 21a by making sure that there is a gap between the outer ring outer peripheral cylindrical surface of the ball bearing 55 and the inner surface fitting portion cylindrical surface of the small gear 21. The structure can be configured to receive only the thrust load without directly receiving the load.

8A to 8C are partial perspective views of the rotary shaft module 10. In these drawings, the reduction gear outer peripheral case 13, the output shaft flange 15, the large bearings 18a and 18b, the parallel shaft gears 17, 19 and the like are omitted for the purpose of facilitating understanding.

FIG. 8A corresponds to a portion of the rotary shaft module 10 shown in FIG. In FIG. 8B, the supporting member 51b of the first two-stage gear 21 and the supporting member 51b of the second two-stage gear 22 are connected to each other by a reinforcing member 61a, for example, a beam member. Further, in FIG. 8C, the arm member 51c of the first two-stage gear 21 and the support member 51b of the second two-stage gear 22 are connected to each other by a reinforcing member 61b.

In this way, the supporting members 51b of the two two-stage gears adjacent to each other are connected to each other by the reinforcing member 61a. As a result, the supporting member 51b of the first two-stage gear 21 and the supporting member 51b of the second two-stage gear 22 can be made more difficult to fall down. It is preferable that the reinforcing member 61a is attached after adjusting the backlash of the two-stage gears 21 and 22.

Further, although not shown in the drawings, two other two-stage gears may be connected to each other by a reinforcing member, or three or more two-stage gears may be connected by a single reinforcing member. Further, it is also included in the scope of the present invention to connect two two-stage gears that are not adjacent to each other, for example, the second two-stage gear 22 and the fourth two-stage gear 24 with a reinforcing member.

9A and 9B are partially transparent end views of the rotating shaft module. In FIG. 9A, the number of teeth of the parallel shaft gear 17 is relatively small, and the number of teeth of the small gear 21a of the first two-stage gear 21 is relatively large. On the other hand, in FIG. 9B, the number of teeth of the parallel shaft gear 17'is relatively large, and the number of teeth of the small gear 21a of the first two-stage gear 21 is relatively small.

Here, it is assumed that the total reduction ratio of the configuration shown in FIG. 9A and the total reduction ratio of the configuration shown in FIG. 9B are the same. In FIG. 9A, the reduction ratio of the fifth stage, that is, the first two-stage gear 21 is small. Therefore, in the configuration shown in FIG. 9A, between the second two-stage gear 22 and the fourth two-stage gear 24. It is necessary to secure a large reduction ratio in.

In this regard, in a plurality of continuous two-stage gear groups, it is necessary to increase the diameter difference between the small gear and the large gear in the final stage two-stage gear. The reason is that the reduction ratio cannot be secured even in the two-stage gear one stage before the final stage. Therefore, it is necessary to secure a reduction ratio between the large gear 21b of the first two-stage gear 21 and the small gear 22a of the second two-stage gear 22 shown in FIG. 9A. Therefore, in the configuration shown in FIG. 9A, it is necessary to increase the size of the speed reducer outer peripheral case 13, and the size of the rotary shaft module 10 is increased.

On the other hand, in the configuration shown in FIG. 9B, the number of teeth of the parallel shaft gear 17'is larger than the number of teeth of the parallel shaft gear 17. The reduction ratio between the parallel shaft gear 17'and the small gear 21a of the first two-stage gear 21 is the small gear 22a of the large gear 21b of the first two-stage gear 21 and the small gear 22a of the second two-stage gear 22. Greater than the reduction ratio between. That is, in the configuration shown in FIG. 9B, the diameter of the large gear 21b of the first two-stage gear 21 can be made relatively small, and as a result, the reduction gear outer peripheral case 13 can be made small.

FIG. 10 is a cross-sectional view of the two-stage gear. In FIG. 10, a second two-stage gear 22 is shown as an example. However, the other two-stage gears 21, 23, and 24 may have substantially the same configuration.

In FIG. 10, the shaft portion 25 extends perpendicularly to the outer end face from the center of the outer end face of the large gear 22b. Further, a support base 40 having a recess 41 formed on the upper surface is mounted on the mounting flange 16. As shown, the shaft portion 25 of the second two-stage gear 22 is rotatably inserted into the recess 41 on the upper surface via the bearing 45. Therefore, in the configuration shown in FIG. 10, the second two-stage gear 22 is cantilevered and supported.

In such a configuration, since the bearing on the small gear 22a side can be eliminated, the diameter of the small gear 22a can be further reduced as compared with the configuration shown in FIG. 7B in which the needle-shaped roller bearing 56 is arranged. It is possible to take a larger reduction ratio per meshing part. Further, the bearing 45 that supports the shaft portion 25 is preferably a bearing having a relatively large capacity for receiving a moment, for example, an angular back surface combination bearing.

11A is a partial cross-sectional view of the rotary shaft module, and FIG. 11B is a partially enlarged view showing a part of FIG. 11A. As shown in FIG. 11B, a sealing member is arranged between the reduction gear outer peripheral case 13 and the output shaft flange 15. The sealing member is an oil seal 71 and may include at least one main lip 72. As can be seen from FIG. 11B, the main lip 72 is in contact with the output shaft flange 15 with a small contact area.

In general, the rotational friction of the oil seal can cause a decrease in the efficiency of external force transmission from the output shaft side to the input shaft side. Therefore, in the present invention, the main lip 72 having the minimum necessary tense force is used as long as the sealing function is not impaired. Therefore, the minimum rotational friction can be achieved, and therefore the minimum friction loss can be achieved. Therefore, it can be seen that the transmission efficiency can be further improved. It is desirable that such a low tension oil seal be applied to all oil seals used in the rotating shaft module.

FIG. 12 is a cross-sectional view of a rotary shaft module based on another embodiment of the present invention. In FIG. 12, the axis of the drive motor 90 is perpendicular to the central axis (output axis) of the rotary axis module 10. A first bevel gear 91a is attached to the output shaft of the drive motor 90, and the first bevel gear 91a engages with the second bevel gear 91b. Then, the second bevel gear 91b engages with the large gear 24b of the fourth two-stage gear 24. That is, in the configuration shown in FIG. 12, the first bevel gear 91a and the second bevel gear 91b form the transmission gear 91.

In such a case, by arranging the drive motor 90 so that the rotation axis of the drive motor 90 is parallel to the output shaft flange 15, the length of the rotation shaft module 10 in the output shaft direction can be shortened. Although the drive motor 90 is arranged near the end of the hollow hole 12a in FIG. 12, it is necessary to prevent the drive motor 90 from closing the opening of the hollow hole 12a.

By the way, FIG. 13 is a diagram showing a robot in which the rotary shaft module of the present invention is used. The robot 1 shown in FIG. 13 is a six-axis vertical multi-contact robot, and includes six joint axes J1 to J6. Each joint shaft is driven by the rotary shaft module 10 or the rotary shaft module 10'described above.

The arm of the robot 1 is composed of a plurality of arm portions, and the rotary shaft modules 10 and 10'are arranged between two adjacent arm portions. The robot 1 shown in FIG. 13 includes three rotary shaft modules 10 and three rotary shaft modules 10'smaller than the rotary shaft module 10.

Since the robot 1 is composed of the rotary shaft modules 10, 10'and a plurality of arm portions, it is easy to rearrange the robot 1 according to the change of the user's application. Further, the manufacturer of the robot 1 also has an advantage that the manufacturing can be easily automated.

All the axes of the robot may be composed of the same rotation axis module, but in general, the arm weight on the terminal side of the terminal axis of the robot 1 becomes lighter, so that the same rotation axis module 10 is used for the entire robot 1. There is no need to use. In the present invention, three rotary shaft modules 10 are arranged on the base end side of the robot 1, and three rotary shaft modules 10'are arranged on the terminal side of the robot 1. In other words, a small rotary shaft module 10'is used on the terminal side of the robot 1.

Therefore, the weight and cost of the entire arm can be reduced as compared with the case where the same rotating shaft module is used for all shafts. Further, when the mounting interface of the rotary shaft module is common to all shafts, the arm weight on the terminal side of the shaft becomes lighter as the shaft becomes closer to the terminal side of the robot 1, and the load acting on the movable member is reduced. , The number of bolts required to fix the rotary shaft modules 10, 10'may be reduced.

Although the present invention has been described using typical embodiments, those skilled in the art can make the above-mentioned changes and various other changes, omissions, and additions without departing from the scope of the present invention. You can understand that.

1 Robot 10, 10'Rotating shaft module 11 Input shaft 12 Output shaft 12a Hollow hole 13 Reducer outer peripheral case 15 Output shaft flange 16 Mounting flange 17, 17'External gear, parallel shaft gear 18a, 18b Large bearing 19 Internal gear, parallel Shaft gears 21 to 24 Two-stage gears 21a to 24a Small gears 21b to 24b Large gears 30a, 30b Planetary gear reduction mechanism 31a, 31b Sun gears 32a, 32b Planetary gears 33a, 33b Internal gears 34 Carriers 40 Support bases 41 Recesses 45 Bearings 51 ~ 54 Gear support 51a Base 51b Support member 51c Arm member 55 Ball bearing (support bearing)
56 Needle roller bearing (supporting bearing)
61a Reinforcing member 71 Oil seal 72 Main lip 90 Drive motor 91 Transmission gear 91a First bevel gear 91b Second bevel gear

Claims (15)

The input shaft (11) driven by the drive motor (90) and
Output shaft (12) and
An output shaft flange (15) connected to the output shaft and
Parallel shaft gears (17, 19) coupled to the output shaft flange,
A speed reducer outer peripheral case (13) rotatably supported by the output shaft flange,
A two-stage gear train including at least two two-stage gears (21 to 24) arranged in the reduction gear outer peripheral case, and a two-stage gear train.
A transmission gear for transmitting the two-stage gear train power of the drive motor via the input shaft (91),
A bearing (18a, 18b) whose inner ring side is coupled to the output shaft flange is provided.
The parallel shaft gear engages with the small gear of one of the at least two two-stage gears, and the large gear of the other two-stage gear of the at least two two-stage gears and the above. It is engaged with the transmission gear and
The at least two two-stage gears and the transmission gear are arranged in a space between the inner surface of the speed reducer outer peripheral case and the output shaft so as to surround the output shaft.
A mounting flange (16) arranged to face the output shaft flange (15) is further provided.
Each of the at least two two-stage gears (21 to 24) has a gear support portion (51 to 54), and only one end side of the gear support portion (51 to 54) is attached to the mounting flange (16). Engage and
The arrangement position of the gear support portions (51 to 54) can be adjusted.
A rotary shaft module in which the parallel shaft gear is supported by the bearings (18a, 18b) via the output shaft flange. The input shaft (11) driven by the drive motor (90) and
Output shaft (12) and
An output shaft flange (15) connected to the output shaft and
Parallel shaft gears (17, 19) coupled to the output shaft flange,
A speed reducer outer peripheral case (13) rotatably supported by the output shaft flange,
A two-stage gear train including at least two two-stage gears (21 to 24) arranged in the reduction gear outer peripheral case, and a two-stage gear train.
A transmission gear for transmitting the two-stage gear train power of the drive motor via the input shaft (91),
A bearing (18a, 18b) whose inner ring side is coupled to the output shaft flange is provided.
The parallel shaft gear engages with the small gear of one of the at least two two-stage gears, and the large gear of the other two-stage gear of the at least two two-stage gears and the above. It is engaged with the transmission gear and
The at least two two-stage gears and the transmission gear are arranged in a space between the inner surface of the speed reducer outer peripheral case and the output shaft so as to surround the output shaft.
Each of the at least two two-stage gears is supported by a supporting bearing (55, 56) and a supporting member (51b), and the supporting member is fixed only to a mounting flange (16) to which the drive motor is mounted. Has been
The arrangement position of the support member (51b) is adjustable.
A rotary shaft module in which the parallel shaft gear is supported by the bearings (18a, 18b) via the output shaft flange. Each of the at least two two-stage gears is supported by a supporting bearing (55, 56) and a supporting member (51b), and the supporting member is fixed to a mounting flange (16) to which the drive motor is mounted. The rotary shaft module according to claim 1. The rotary shaft module according to any one of claims 1 to 3, wherein a hollow hole (12a) into which a striatum is to be inserted is formed in the output shaft. The rotary shaft module according to any one of claims 1 to 4, wherein the parallel shaft gear is an internal gear. The rotary shaft module according to any one of claims 1 to 5, wherein the bearings (18a, 18b) are angular back combination bearings. The rotary shaft module according to claim 3, wherein at least one of the supporting members of the two-stage gear is supported on both the small gear side and the large gear side. The claim that after adjusting the arrangement position of the support member (51b), each support member of the at least two two-stage gears is connected to each other by a reinforcing member (61a) as a beam member. The rotary shaft module according to 2 or 3. The rotary shaft module according to claim 2 or 3, wherein the supporting bearing of at least one of the at least two two-stage gears includes a needle roller bearing. The rotary shaft module according to claim 2 or 3, wherein the supporting bearing of at least one of the at least two two-stage gears includes a ball bearing. The reduction ratio between the parallel shaft gear and the small gear of one of the two-stage gears of the at least two two-stage gears is the reduction ratio of the large gear of the one two-stage gear and the small gear of the at least two two-stage gears. The rotary shaft module according to any one of claims 1 to 10, wherein the reduction ratio is larger than the reduction ratio between the other two-stage gear and the small gear. The at least two two-stage gears include a shaft portion (25) extending from the end face of the large gear.
The rotary shaft module according to claim 1 or 2, wherein the shaft portion is supported so as to support the two-stage gear cantilever. According to any one of claims 1 to 12, the at least one lip (72) of the oil seal (71) used in the rotary shaft module has the minimum necessary tension as long as the sealing function is not impaired. The rotating shaft module described. The rotary shaft module according to any one of claims 1 to 13, wherein the drive motor is mounted so that the input shaft of the drive motor is parallel to the mounting surface of the output shaft flange. An articulated robot comprising at least one rotary axis module according to any one of claims 1 to 14.

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