Articulated robot

Abstract

To enhance the supporting strength of joints in an articulated robot.SOLUTION: An articulated robot 1 includes: a first joint (joint JT1) having a first support section (support section 23) and a first operation section (first end 311) which are arranged in a direction of extension of a first axis (axis Ax1); a first actuator (actuator 41) which has a first body (body 411) and a first shaft (shaft 421) and in which the first body is positioned on an opposite side to the first support section with respect to the first operation section; a second joint (joint JT2) which is in series with the first joint and is supported by the first joint, and has a second supporting section (second end 312) and a second operation section (first end 321); and a second actuator (actuator 42) which has a second body (body 421) and a second shaft (shaft 422), a projecting direction of the second shaft being opposite to the projecting direction of the first shaft in a direction of extension of the first axis or a second axis (axis Ax2).SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The technology disclosed herein relates to an articulated robot. [Background technology]

[0002] Patent Document 1 describes a conventional articulated robot. The conventional articulated robot is a seven-joint robot. The conventional articulated robot includes a first arm, a second arm, and a third arm connected in series. An actuator in the first arm swings the first arm around a horizontal axis, an actuator in the second arm swings the second arm around a horizontal axis, and an actuator in the third arm swings the third arm around a horizontal axis. The three actuators are located on the same side in the direction along the horizontal axis with respect to the first arm and the second arm. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5975129 Summary of the Invention [Problem to be solved by the invention]

[0004] In a multi-joint robot in which multiple joints are connected in series, a specific joint supports one or more other joints, so the support strength of the specific joint is increased. For example, a typical six-axis multi-joint robot includes a first arm connected to a rotating part and a second arm connected to the first arm. The specific joint connecting the rotating part and the first arm supports the second joint connecting the first arm and the second arm, so the support strength of the specific joint is increased.

[0005] In the conventional articulated robot, the joint connecting the rotating part and the first arm requires a higher support strength than the joints of a general six-axis articulated robot, because the conventional articulated robot has more arms and actuators than the general six-axis articulated robot.

[0006] The joint of the conventional articulated robot has a connection part of the rotating part and a base end part of the first arm part supported by the connection part. The actuator is fixed to the connection part. Since the actuator is fixed to the connection part, it is difficult to enlarge the connection part in order to increase the support strength of the joint. Unfortunately, in the conventional articulated robot, it is not possible to increase the support strength of the joint. [Means for solving the problem]

[0007] The present disclosure relates to an articulated robot. a first joint having a first support portion and a first operating portion aligned in a direction in which a horizontal first axis extends, and the first operating portion rotates relatively to the first support portion around the first axis; a first actuator having a first body and a first shaft protruding from the first body and connected to the first joint, and moving the first joint through the first shaft, the first body being located on the opposite side to the first support part with respect to the first operating part; a second joint that is in series with the first joint and supported by the first joint, the second joint having a second support portion and a second operating portion supported by the second support portion, and the second operating portion rotates relatively to the second support portion around a second axis that is parallel to the first axis; a second actuator having a second body and a second shaft protruding from the second body and connected to the second joint, and moving the second joint through the second shaft, wherein the protruding direction of the second shaft is opposite to the protruding direction of the first shaft with respect to the extending direction of the first axis or the second axis; Equipped with. Effect of the Invention

[0008] The first joint of the articulated robot does not directly support the first actuator, and therefore can have high supporting strength. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a rear view of the articulated robot. [Diagram 2] FIG. 2 is a side view of the articulated robot. [Diagram 3] FIG. 3 is a partial cross-sectional view of the articulated robot seen from behind, showing the first to third joints and the first to third actuators in an enlarged manner. [Figure 4] FIG. 4 is a partial cross-sectional view of a modified articulated robot seen from behind. [Diagram 5] FIG. 5 is a partial cross-sectional view of a modified articulated robot seen from behind. [Figure 6] FIG. 6 is a partial cross-sectional view of a modified articulated robot seen from behind. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the articulated robot will be described with reference to the drawings. The articulated robot described here is merely an example.

[0011] (Overall structure of an articulated robot) Fig. 1 shows an articulated robot 1. Fig. 1 is a rear view of the articulated robot 1. Fig. 2 is a side view of the articulated robot 1. The articulated robot 1 is a vertical articulated robot. The articulated robot 1 is a seven-axis robot equipped with joints JT1-JT7.

[0012] The articulated robot 1 is used, for example, in the field of logistics. Specifically, the articulated robot 1 loads and unloads items onto and from the bed of a truck or a container. In FIG. 1 or 2, the articulated robot 1 is installed on a floor 100. The floor 100 is, for example, the floor of the bed of a truck. The articulated robot 1 may be placed on a cart and moved by the cart. Note that the use of the articulated robot 1 is not limited to logistics applications. The articulated robot 1 can be used in various fields.

[0013] The articulated robot 1 includes a base 21. Note that the base 21 is not an essential element of the articulated robot 1. The base 21 includes a base body 22. The base body 22 has a flat upper surface. The base 21 includes a support portion 23. The support portion 23 is fixed to the upper surface of the base body 22.

[0014] The articulated robot 1 includes a first link 31. The joint JT1 connects the first link 31 to the base 21. The first link 31 is an arm having a first end 311 and a second end 312. The first end 311 of the first link 31 is connected to the support portion 23 of the base 21. The joint JT1 has the first end 311 and the support portion 23. The first link 31 rotates relative to the base 21 around an axis Ax1. The axis Ax1 is a horizontal axis that is parallel to the floor 100.

[0015] The articulated robot 1 includes a second link 32. The joint JT2 connects the second link 32 and the first link 31. The second link 32 is an arm having a first end 321 and a second end 322. The first end 321 of the second link 32 is connected to the second end 312 of the first link 31. The joint JT2 has the first end 321 of the second link 32 and the second end 312 of the first link 31. The second link 32 rotates relative to the first link 31 around the axis Ax2. The second axis Ax2 is an axis parallel to the first axis Ax1.

[0016] The articulated robot 1 includes a third link 33. The third link 33 is not an essential element of the articulated robot 1. The joint JT3 connects the third link 33 and the second link 32. The third link 33 has a first end 331 and a second end 332. The first end 331 of the third link 33 is connected to the second end 322 of the second link 32. The joint JT3 has the first end 331 of the third link 33 and the second end 322 of the second link 32. The third link 33 rotates relative to the second link 32 around the axis Ax3. The axis Ax3 is an axis parallel to the axes Ax1 and Ax2.

[0017] The base 21 rotates around an axis Ax4. The axis Ax4 is an axis perpendicular to the floor 100 and perpendicular to the axis Ax1. The base 21 has a joint JT4. The joint JT4 rotates the base 21 around the axis Ax4. As the base 21 rotates, the first link 31, the second link 32, and the third link 33 rotate around the axis Ax4.

[0018] The joint JT5 rotates the third link 33 about an axis Ax5. The axis Ax5 is an axis perpendicular to the axis Ax1.

[0019] The articulated robot 1 is equipped with a fourth link 34. Note that the fourth link 34 is not an essential element of the articulated robot 1. The joint JT6 connects the fourth link 34 and the third link 33. The joint JT6 rotates the fourth link 34 relative to the third link 33 about the axis Ax6. The axis Ax6 is an axis parallel to the axis Ax1.

[0020] The joint JT7 rotates the fourth link 34 about an axis Ax7. The axis Ax7 is an axis perpendicular to the axis Ax1.

[0021] The articulated robot 1 is equipped with a hand 11 as an end effector. The hand 11 holds an object. Note that the hand 11 that holds an object is not an essential element of the articulated robot 1. The end effector of the articulated robot 1 is selected depending on the application of the articulated robot 1.

[0022] The articulated robot 1 includes a joint JT8. The articulated robot 1 can be called an 8-axis robot. The articulated robot 1 includes a second base 35. The second base 35 is interposed between a floor 100 and the base 21. The base 21 and the second base 35 are offset from each other in the horizontal direction. In order to distinguish the base 21 from the second base 35, the base 21 may be called the first base 21 below.

[0023] The joint JT8 rotates the second base 35 about an axis Ax8. The axis Ax8 is an axis parallel to the axis Ax4 and perpendicular to the axis Ax1.

[0024] The articulated robot 1 includes a horizontal link 36. The horizontal link 36 extends in the horizontal direction. A first end of the horizontal link 36 is fixed to the second base 35. When the second base 35 rotates, the horizontal link 36 rotates about the axis Ax8. A second end of the horizontal link 36 is fixed to the first base 21. The horizontal link 36 and the second base 35 support the seven-axis articulated robot 1. When the horizontal link 36 rotates, the position of the seven-axis articulated robot 1 changes.

[0025] Incidentally, the second base 35 and the horizontal link 36 are not essential elements of the articulated robot 1.

[0026] The articulated robot 1 includes an actuator. The actuator is a power source that moves the joints. The actuator is, for example, an electric motor. The electric motor is, for example, a servo motor. The electric motor may be a step motor.

[0027] FIG. 1 or FIG. 2 shows actuators 41, 42, 43, 44, 45, and 46 among the actuators included in the articulated robot 1.

[0028] The actuator 41 is connected to the joint JT1. The actuator 41 moves the joint JT1. The actuator 42 is connected to the joint JT2. The actuator 42 moves the joint JT2. The actuator 43 is connected to the joint JT3. The actuator 43 moves the joint JT3. Note that the actuator 43 is not an essential element of the articulated robot 1.

[0029] The actuator 44 is connected to the joint JT4. The actuator 44 moves the joint JT4. The actuator 45 is connected to the joint JT5. The actuator 45 moves the joint JT5. The actuator 46 is connected to the joint JT8. The actuator 46 moves the joint JT8. Note that the actuators 44, 45, and 46 are not essential elements of the articulated robot 1.

[0030] The actuator is electrically connected to a controller and receives a control signal from the controller. The controller is a computer including at least a processor, a memory, and an interface. The actuator operates according to the control signal. The articulated robot 1 performs a task by the operation of the actuator.

[0031] (Actuator placement) The arrangement of actuators 41, 42, and 43 will be described with reference to Fig. 3. Fig. 3 is a partial cross-sectional view of the articulated robot 1 as viewed from behind. Joints JT1, JT2, and JT3 of the articulated robot 1 are connected in series. Joint JT1 supports joints JT2 and JT3. Joint JT2 supports joint JT3.

[0032] As described above, the joint JT1 has the first end 311 of the first link 31 and the support part 23 of the first base 21. The first end 311 and the support part 23 are aligned in the extension direction of the axis Ax1. The support part 23 supports the first end 311 so that the first link 31 rotates around the axis Ax1.

[0033] The actuator 41 has a main body 411 and a shaft 412. The shaft 412 protrudes from the main body 411 in the direction in which the axis Ax1 extends. The shaft 412 is a rotor of an electric motor, and is an output shaft of the actuator 41. The actuators 42 and 43 described below have the same structure as the actuator 41.

[0034] The shaft 412 is connected to the joint JT1. More specifically, in the example of FIG. 3, the shaft 412 is coaxial with the axis Ax1, and is connected to the joint JT1 via the reducer 413. The reducer 413 reduces the speed of the output of the actuator 41 and outputs the reduced speed to the joint JT1. The reducer 413 is, for example, a planetary gear mechanism. However, the reducer 413 is not limited to a planetary gear mechanism. Note that the reducers 423 and 433 described below are the same as the reducer 413.

[0035] The first link 31 supports a main body 411. More specifically, the main body 411 is located on the opposite side to the support part 23 with respect to the first end 311 in the direction in which the axis Ax1 extends. The main body 411 protrudes from the first end 311 in the direction in which the axis Ax1 extends. The main body 411 is fixed to the first end 311. When the first link 31 rotates, the main body 411 rotates together with the first link 31 about the axis Ax1.

[0036] As described above, the joint JT2 has the first end 321 of the second link 32 and the second end 312 of the first link 31. The first end 321 and the second end 312 are aligned in the direction in which the axis Ax2 extends. The second end 312 supports the first end 321 so that the second link 32 rotates around the axis Ax2.

[0037] The actuator 42 has a main body 421 and a shaft 422. The shaft 422 protrudes from the main body 421 in the direction in which the axis Ax2 extends.

[0038] The shaft 422 is coaxial with the axis Ax2, and is connected to the joint JT2 via a reducer 423. Here, with respect to the direction in which the axis Ax1 or the axis Ax2 extends, the direction in which the shaft 422 protrudes is opposite to the direction in which the shaft 412 protrudes. In other words, the shaft 412 protrudes from right to left on the paper surface in Fig. 3, and the shaft 422 protrudes from left to right on the paper surface in Fig. 3.

[0039] The first link 31 supports a main body 421. More specifically, the main body 421 is located on the opposite side to the first end 321 with respect to the second end 312 in the direction in which the axis Ax2 extends. In other words, the actuator 41 and the actuator 42 are located on opposite sides with respect to the first link 31. In FIG. 3, the actuator 41 is located on the right side of the first link 31, and the actuator 42 is located on the left side of the first link 31. The main body 421 protrudes from the second end 312 in the direction in which the axis Ax2 extends. The main body 421 is fixed to the second end 312.

[0040] As described above, the joint JT3 has the first end 331 of the third link 33 and the second end 322 of the second link 32. The first end 331 and the second end 322 are aligned in the direction in which the axis Ax3 extends. The second end 322 supports the first end 331 so that the third link 33 rotates around the axis Ax3.

[0041] The actuator 43 has a main body 431 and a shaft 432. The shaft 432 protrudes from the main body 431 in the direction in which the axis Ax3 extends.

[0042] The shaft 432 is coaxial with the axis Ax3, and is connected to the joint JT3 via a reduction gear 433. Here, with respect to the direction in which the axis Ax1, the axis Ax2, or the axis Ax3 extends, the direction in which the shaft 432 protrudes is opposite to the direction in which the shaft 412 protrudes and is the same as the direction in which the shaft 422 protrudes.

[0043] The third link 33 supports a main body 431. More specifically, the main body 431 is located on the opposite side to the second end 322 with respect to the first end 331 in the direction in which the axis Ax3 extends. With respect to the second link 32, the actuators 42 and 43 are located on the same side. With respect to the first link 31 and the second link 32, the actuators 41 and 43 are located on opposite sides to each other. The main body 431 protrudes from the first end 331 in the direction in which the axis Ax3 extends.

[0044] (Action and effect) The articulated robot 1 is a seven-axis vertical articulated robot. The seven-axis articulated robot 1 has a high degree of freedom in its posture, so it can efficiently transport articles in a narrow space such as the bed of a truck. The articulated robot 1 is also an eight-axis articulated robot equipped with a second base 35. The eight-axis articulated robot 1 has an even higher degree of freedom in its posture, so it can transport articles even more efficiently in a narrow space.

[0045] A high support strength is required for the joint JT1 of the articulated robot 1. This is because the joint JT1 supports at least the joints JT2, JT3, actuators 42 and 43 that are connected in series to the joint JT1. In addition, the articulated robot 1 is a seven-axis vertical articulated robot, and therefore has a greater number of joints and actuators than a typical six-axis vertical articulated robot. Therefore, a higher support strength is required for the joint JT1.

[0046] The fact that the joint JT1 supports the joints JT2 and JT3 may be rephrased as, the joint JT1 is closer to the first base 21 than the joints JT2 and JT3. The joints JT2 and JT3 may be rephrased as, the joints JT1 and JT3 are located higher than the joint JT1.

[0047] The actuator 41 is located on the opposite side of the support portion 23 of the first base 21 with respect to the first end 311 of the first link 31. The first end 311 supports the actuator 41. The support portion 23 does not directly support the actuator 41. As shown in FIG. 3, since the support portion 23 does not directly support the actuator 41, the thickness t1 of the support portion 23 can be increased without being affected by the actuator 41. More specifically, the thickness t1 is the thickness t1 in the direction in which the axis Ax1 extends. Since the thickness t1 of the support portion 23 is large, the joint JT1 can have the necessary strength.

[0048] In a multi-joint robot in which multiple joints are connected in series, it is common in the conventional design concept that multiple actuators are located on the same side with respect to the links. The actuator 41 of the multi-joint robot 1 is located on the opposite side of the support part 23 with respect to the first link 31. According to the conventional design concept, as shown by the imaginary line in FIG. 3, the actuators 420 and 430 are located on the same side as the actuator 41 with respect to the first link 31 and the second link 32. However, the actuators 420 and 430 located on the same side as the actuator 41 increase the turning radius r1. The turning radius here is the distance from the axis Ax4, which is the turning axis of the multi-joint robot 1, to the end of the actuator in the direction perpendicular to the axis Ax4. The increase in turning radius r1 increases the moment around the axis Ax4 of the multi-joint robot 1. Also, the increase in turning radius r1 increases the size of the multi-joint robot, which is disadvantageous for a robot that works in a narrow space.

[0049] In contrast, in the articulated robot 1, the orientation of the actuator 42 is opposite to that of the actuator 41. That is, the protruding direction of the shaft 422 is opposite to that of the shaft 412. With the reversal of the orientation of the actuator 42, the actuator 42 is located on the opposite side of the actuator 41 with respect to the first link 31. The actuator 42 located on the opposite side of the actuator 41 has a small turning radius r2. The fact that the turning radius r2 of the actuator 42 located away from the first base 21 is small is effective in reducing the moment around the axis Ax4 of the articulated robot 1. The turning radius of the actuator 41 is relatively large. However, since the actuator 41 is close to the first base 21, there is substantially no inconvenience caused by the large turning radius.

[0050] In the articulated robot 1, (a) the support strength of the joints is improved, and (b) the turning radius is reduced, due to the positional relationship between the joint JT1, the actuator 41, the joint JT2, and the actuator 42. In the articulated robot 1 of FIG. 3, the joint JT1 corresponds to a first joint having a first support part and a first operating part aligned in a direction in which a horizontal first axis extends. The first axis is the axis Ax1, the first support part is the support part 23, and the first operating part is the first end 311. The actuator 41 corresponds to a first actuator in which the main body 411 is located on the opposite side of the first support part with respect to the first operating part. The joint JT2 corresponds to a second joint that is in series with the first joint and is supported by the first joint. The second axis of the second joint is the axis Ax2, the second support part is the second end 312, and the second operating part is the first end 321. The actuator 42 corresponds to a second actuator having a shaft protruding in a direction opposite to that of the first shaft. The first shaft here is the shaft 412 of the actuator 41.

[0051] In the articulated robot 1, the actuator 43 is also oriented in the opposite direction to the actuator 41. The actuator 43 is oriented in the same direction as the actuator 42. That is, the protruding direction of the shaft 432 is opposite to the protruding direction of the shaft 412 and is the same as the protruding direction of the shaft 422. The actuator 43 is located on the opposite side to the actuator 41 with respect to the first link 31 and the second link 32. The actuator 43 also has a small turning radius r2. The fact that the turning radius r2 of the actuator 43, which is located further away from the first base 21, is small is effective in reducing the moment around the axis Ax4 of the articulated robot 1. In the articulated robot 1 of FIG. 3, the joint JT3 corresponds to a third joint that is in series with the first joint and the second joint and supported by the first joint. The third axis of the third joint is the axis Ax3, the third support portion is the second end 322, and the third operating portion is the first end 331. Actuator 43 corresponds to a third actuator having a shaft that protrudes in a direction opposite to that of the first shaft and the same as that of the second shaft. Here, the first shaft is shaft 412 of actuator 41, and the second shaft is shaft 422 of actuator .

[0052] The reduction in the turning radius r2 of the actuator 42 and the actuator 43 reduces the size of the articulated robot 1. The articulated robot 1 is advantageous for use in a narrow space.

[0053] 3, the position of the axis Ax4 is a position where the axis Ax4 intersects with the actuator 42 and the actuator 43. The position of the axis Ax4 is not limited to this position.

[0054] 3, if attention is paid only to the positional relationship between actuator 41 and actuator 43 among actuators 41, 42, and 43, joint JT1 corresponds to the first joint, and actuator 41 corresponds to the first actuator. Joint JT3 corresponds to the second joint that is in series with and supported by the first joint, and actuator 43 corresponds to the second actuator whose shaft protrudes in the opposite direction to that of the first shaft. Here, the first shaft is shaft 412 of actuator 41. Due to the positional relationship between joint JT1, actuator 41, joint JT3, and actuator 43, in the articulated robot 1, (a) improvement in the support strength of the joints and (b) reduction in the turning radius can be obtained.

[0055] (Variation 1) 4 shows a modified example regarding the position of actuator 43. The orientation of actuator 43 is the same as that of actuator 41. The orientation of actuator 43 is opposite to that of actuator 42. In other words, the protruding direction of shaft 432 is the same as that of shaft 412 and is opposite to that of shaft 422.

[0056] The actuator 43 is located on the same side as the actuator 41 with respect to the first link 31 and the second link 32. The second end 322 of the second link 32 supports a main body 431. The main body 431 protrudes from the second end 322 in the direction in which the axis Ax3 extends. The turning radius of the actuator 43 is relatively large. However, the actuator 43 of the joint JT3 is smaller or lighter than the actuator 41 or the actuator 42. This is because the joint JT3 is a joint closer to the tip side than the joints JT1 and JT2 in the multi-joint robot 1. The effect of the large turning radius of the actuator 43 on the multi-joint robot 1 is limited.

[0057] In the articulated robot 1 of the first modification, the above-mentioned (a) improvement in the support strength of the joints and (b) reduction in the turning radius can be obtained due to the positional relationship between the joint JT1, the actuator 41, the joint JT2, and the actuator 42. The joint JT1 corresponds to the first joint, and the actuator 41 corresponds to the first actuator. The joint JT2 corresponds to the second joint, and the actuator 42 corresponds to the second actuator.

[0058] (Variation 2) 5 shows a modified example regarding the position of actuator 42. The orientation of actuator 42 is the same as that of actuator 41. The orientation of actuator 42 is opposite to that of actuator 43. In other words, the protruding direction of shaft 422 is the same as that of shaft 412 and is opposite to that of shaft 432.

[0059] The actuator 42 is located on the same side as the actuator 41 with respect to the first link 31. A first end 321 of the second link 32 supports a main body 421. The main body 421 protrudes from the first end 321 in the direction in which the axis Ax2 extends.

[0060] The first end 321 of the second link 32 supports the actuator 42. In the joint JT2, the second end 312 of the first link 31 supporting the first end 321 does not directly support the actuator 42. The thickness t2 of the second end 312 can be increased. The joint JT3 and the joint JT2 supporting at least the actuator 43 can have the necessary strength.

[0061] The actuator 43 is located on the opposite side to the actuators 41 and 42 with respect to the first link 31 and the second link 32. The actuator 43 reduces the turning radius r2. The moment around the axis Ax4 of the articulated robot 1 is small.

[0062] In the articulated robot 1 of the second modification, if we focus only on the positional relationship between the actuator 42 and the actuator 43 among the actuators 41, 42, and 43, the joint JT2 corresponds to a first joint having a first support part and a first operating part aligned in the direction in which the horizontal first axis extends. The first axis is the axis Ax2, the first support part is the second end 312, and the first operating part is the first end 321. The actuator 42 corresponds to a first actuator in which the main body 421 is located on the opposite side to the first support part with respect to the first operating part. The joint JT3 corresponds to a second joint that is supported by the first joint in series with the first joint, and the actuator 43 corresponds to a second actuator whose shaft protrudes in the opposite direction to the first shaft. Here, the first shaft is the shaft 422 of the actuator 42. In the articulated robot 1 of the second modification, the positional relationship between the joint JT2, the actuator 42, the joint JT3, and the actuator 43 provides the above-mentioned (a) improvement in the support strength of the joints and (b) reduction in the turning radius.

[0063] In the second modification, the orientation of the actuator 41 may be inverted as shown in an imaginary manner in Fig. 5. The main body 411 of the actuator 41 may be supported by the support portion 23 of the first base 21.

[0064] Furthermore, in the articulated robot 1 of the modified example 2, if attention is paid only to the positional relationship between the actuator 41 and the actuator 43 among the actuators 41, 42, and 43, the joint JT1 corresponds to the first joint, and the actuator 41 corresponds to the first actuator. The joint JT3 corresponds to the second joint that is in series with the first joint and supported by the first joint, and the actuator 43 corresponds to the second actuator whose shaft protrudes in the opposite direction to the first shaft. Here, the first shaft is the shaft 412 of the actuator 41. In the articulated robot 1 of the modified example 2, the positional relationships between the joint JT1, the actuator 42, the joint JT3, and the actuator 43 allow for the above-mentioned (a) improvement in the support strength of the joints and (b) reduction in the turning radius to be obtained.

[0065] (Variation 3) 6 shows a modified example of the number of joints of the articulated robot. The articulated robot 10 may be a 6-axis vertical articulated robot. Compared to the articulated robot 1 of FIG. 3, the articulated robot 10 omits the second link 32 and the actuator 42. The joint JT3 connects the second end 312 of the first link 310 and the first end 331 of the third link 33. The joint JT3 has the second end 312 and the first end 331.

[0066] In the articulated robot 10 of the third modification, the joint JT1 corresponds to the first joint, and the actuator 41 corresponds to the first actuator in which the body 411 is located on the opposite side to the support part 23 which is the first support part with respect to the first end 311 which is the first operating part. The joint JT3 corresponds to the second joint which is supported by the joint JT1 in series, and the actuator 43 corresponds to the second actuator whose shaft protrudes in the opposite direction to the first shaft. Here, the first shaft is the shaft 412 of the actuator 41. In the articulated robot 10 of the third modification, the positional relationship between the joint JT1, the actuator 41, the joint JT3, and the actuator 43 allows the above-mentioned (a) improvement in the support strength of the joints and (b) reduction in the turning radius r3 to be obtained.

[0067] (summary) (1) The articulated robots 1 and 10 disclosed herein are First joints JT1 and JT2 each having a first support portion 23, 312 and a first operating portion 311, 321 aligned in a direction in which horizontal first axes Ax1, Ax2 extend, and the first operating portions 311, 321 rotate relatively to the first support portions 23, 312 about the first axes Ax1, Ax2; a first actuator 41, 42 having a first body 411, 421 and a first shaft 412, 422 protruding from the first body 411, 421 and connected to the first joint JT1, JT2, and moving the first joint JT1, JT2 through the first shaft 412, 422, the first body 411, 421 being located on the opposite side to the first support portion 23, 312 with respect to the first operating portion 311, 321; second joints JT2, JT3 that are in series with the first joints JT1, JT2 and supported by the first joints JT1, JT2, and have second support portions 312, 322 and second operating portions 321, 331 supported by the second support portions 312, 322, and the second operating portions 321, 331 rotate relatively to the second support portions 312, 322 about second axes Ax2, Ax3 parallel to the first axes Ax1, Ax2; a second actuator 42, 43 including a second body 421, 431 and a second shaft 422, 432 protruding from the second body 421, 431 and connected to the second joint JT2, JT3, and moving the second joint JT2, JT3 through the second shaft 422, 432, wherein the protruding direction of the second shaft 422, 432 is opposite to the protruding direction of the first shaft 412, 422 with respect to the extending direction of the first axis Ax1, Ax2 or the second axis Ax2, Ax3; Equipped with.

[0068] Since the first support portions 23, 312 do not directly support the first actuators 41, 42, it is possible to increase the thicknesses t1, t2 of the first support portions 23, 312. The first joints JT1, JT2 can have high supporting strength.

[0069] In the first joints JT1, JT2 and the second joints JT2, JT3 connected in series, the second actuators 42, 43 are oriented in the opposite direction to the first actuators 41, 42, so that the turning radii r2, r3 are small. The small turning radii r2, r3 reduce the moment generated in the articulated robots 1, 10. The small turning radii r2, r3 also reduce the size of the articulated robots 1, 10.

[0070] (2) In the articulated robot 1, 10 described in (1), The first bodies 411, 421 are located on a first side based on the first joints JT1, JT2 in a direction in which the first axes Ax1, Ax2 or the second axes Ax2, Ax3 extend, The second bodies 421, 431 may be located on a second side opposite to the first side with respect to the second joints JT2, JT3 in the direction in which the first axis Ax1, Ax2 or the second axis Ax2, Ax3 extends.

[0071] Since the first actuators 41, 42 and the second actuators 42, 43 are located on opposite sides of the first joints JT1, JT2 or the second joints JT2, JT3, the turning radii r2, r3 of the articulated robots 1, 10 can be made small.

[0072] (3) In the articulated robot 1, 10 described in (2), The first operating parts 311 and 321 may support the first bodies 411 and 421 .

[0073] The fact that the first support parts 23, 312 do not directly support the first main bodies 411, 421 makes it possible to improve the supporting strength of the first support parts 23, 312.

[0074] (4) In the multi-joint robot 1, 10 according to (2) or (3), The second support portion 312 may support the second body 421 .

[0075] The second support portion 312 supporting the second body 421 is advantageous in reducing the turning radius r2 of the articulated robots 1 and 10.

[0076] (5) The articulated robot 1, 10 according to any one of (1) to (4) above is a third joint JT3 that is in series with the first joint JT1 and the second joint JT2 and is supported by the first joint JT1, the third joint JT3 having a third support portion 322 and a third operating portion 331 supported by the third support portion 322, the third joint JT3 rotating relatively to the third support portion 322 about a third axis Ax3 that is parallel to the first axes Ax1 and Ax2; The actuator may further include a third actuator 43 having a third body 431, a third shaft 432 protruding from the third body 431 and connected to the third joint JT3, and moving the third joint JT3 via the third shaft 432.

[0077] Increasing the number of joints increases the degree of freedom of the posture of the articulated robots 1 and 10. The articulated robots 1 and 10 are advantageous for working in narrow spaces.

[0078] (6) In the articulated robot 1, 10 described in (5), The protruding direction of the third shaft 432 may be opposite to the protruding direction of the first shaft 412 and the same as the protruding direction of the second shaft 422 in the extension direction of the first axis Ax1, the second axis Ax2, or the third axis Ax3.

[0079] Since both the second actuator 42 and the third actuator 43 are oriented in the opposite direction to the first actuator 41, the turning radius r2 of the articulated robots 1 and 10 can be made small.

[0080] (7) The articulated robot 1 according to (5) or (6) is A base 21 which is a fourth joint JT4 which rotates around a fourth axis Ax4 perpendicular to the first axis Ax1; a first link 31 connected to the base 21 via the first joint JT1; a second link 32 connected to the first link 31 via the second joint JT2; a third link 33 connected to the second link 32 via the third joint JT3; a fifth joint JT5 that rotates the third link 33 about a fifth axis Ax5 perpendicular to the first axis Ax1; a fourth link 34 connected to the third link 33; a sixth joint JT6 that is interposed between the third link 33 and the fourth link 34 and rotates the fourth link 34 relatively to the third link 33 about a sixth axis Ax6 that is parallel to the first axis Ax1; The robot may further include a seventh joint JT7 that rotates the fourth link 34 about a seventh axis Ax7 that is perpendicular to the first axis Ax1.

[0081] The articulated robot 1 may be a seven-axis vertical articulated robot. A seven-axis vertical articulated robot can efficiently perform work in a narrow space.

[0082] (8) The articulated robot 1 described in (7) above is The robot may further include a hand 11 for holding an article, the hand 11 being supported by the fourth link 34 .

[0083] The articulated robot 1 is suitable for use in the logistics field. [Explanation of symbols]

[0084] 1 Articulated robot 10 Articulated Robot 11 Hands 21 Base 23 Support part (1st support part) 31 First link 311 1st end (1st operating part) 312 Second end (first support part, second support part) 32 Second Link 321 First end (first operating section, second operating section) 322 Second end (second support part, third support part) 33 Third Link 331 First end (second operating section, third operating section) 34 4th Link 35 2nd Base 36 Horizontal Link 310 First Link 41 Actuator (First Actuator) 411 Main body (First main body) 412 Shaft (1st Shaft) 42 Actuator (first actuator, second actuator) 421 Body (1st body, 2nd body) 422 Shaft (1st shaft, 2nd shaft) 43 Actuator (2nd actuator, 3rd actuator) 431 Body (2nd Body, 3rd Body) 432 Shaft (2nd shaft, 3rd shaft) Ax1 axis (1st axis) Ax2 axis (1st axis, 2nd axis) Ax3 axis (2nd axis, 3rd axis) Ax4 axis Ax5 axis Ax6 axis Ax7 axis Ax8 axis JT1 joint (first joint) JT2 joint (1st joint, 2nd joint) JT3 joint (2nd joint, 3rd joint) JT4 Joint JT5 Joint JT6 Joint JT7 Joint JT8 Joint

Claims

1. a first joint having a first support portion and a first operating portion aligned in a direction in which a horizontal first axis extends, the first operating portion rotating relatively to the first support portion around the first axis; a first actuator having a first body and a first shaft protruding from the first body and connected to the first joint, and moving the first joint through the first shaft, the first body being located on an opposite side to the first support part with respect to the first operating part; a second joint that is in series with the first joint and supported by the first joint, the second joint having a second support portion and a second operating portion supported by the second support portion, the second operating portion rotating relatively to the second support portion around a second axis that is parallel to the first axis; a second actuator having a second body and a second shaft protruding from the second body and connected to the second joint, and moving the second joint through the second shaft, wherein a protruding direction of the second shaft is opposite to a protruding direction of the first shaft with respect to a direction in which the first axis or the second axis extends; An articulated robot comprising:

2. The articulated robot according to claim 1, the first body is located on a first side based on the first joint in a direction in which the first axis or the second axis extends, An articulated robot, wherein the second body is located on a second side opposite to the first side with respect to the direction in which the first axis or the second axis extends, with the second joint as a reference.

3. The articulated robot according to claim 2, The first operating unit supports the first body.

4. The articulated robot according to claim 2 or 3, The second support portion supports the second body.

5. The articulated robot according to claim 1, a third joint that is in series with the first joint and the second joint and is supported by the first joint, the third joint having a third support portion and a third operating portion supported by the third support portion, the third operating portion rotating relatively to the third support portion around a third axis that is parallel to the first axis; A multi-joint robot further comprising: a third body; a third shaft protruding from the third body and connected to the third joint; and a third actuator that moves the third joint through the third shaft.

6. The articulated robot according to claim 5, a protruding direction of the third shaft is opposite to a protruding direction of the first shaft and is the same as a protruding direction of the second shaft in a direction in which the first axis, the second axis, or the third axis extends.

7. The articulated robot according to claim 5 or 6, a base that is a fourth joint that rotates around a fourth axis perpendicular to the first axis; a first link connected to the base via the first joint; a second link connected to the first link via the second joint; a third link connected to the second link via the third joint; a fifth joint that rotates the third link about a fifth axis perpendicular to the first axis; a fourth link connected to the third link; a sixth joint that is interposed between the third link and the fourth link and that rotates the fourth link relatively to the third link about a sixth axis that is parallel to the first axis; a seventh joint that rotates the fourth link about a seventh axis perpendicular to the first axis.

8. The articulated robot according to claim 7, The articulated robot further comprises a hand for holding an object, the hand being supported by the fourth link.

Images