JP7665802B2 - Direct-drive SCARA robot with rear-located center of gravity - Google Patents

Description

CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority to a Chinese patent application filed on December 31, 2020, bearing application number 2020116329334 and entitled "Direct-Drive SCARA Robot with Rear-Mounted Center of Gravity," the entire contents of which are incorporated herein by reference.

The present invention relates to the technical field of robots, and in particular to horizontal articulated robots.

A horizontal articulated robot, also known as SCARA (Selective Compliance Assembly Robot Arm), is a robot arm used in assembly work. In general, a horizontal articulated robot is provided with three rotatable joints: a first joint located at the connection point between the base and the first arm, a second joint located at the connection point between the first arm and the second arm, and a third joint located at one end of the second arm away from the first arm. The axes of the three joints are parallel to each other, and positioning and orientation can be performed within a plane, with simple, efficient, and low-cost operation.

Through long-term research and development, the inventors of the present application have found that, although it is currently common for horizontal articulated robots to have electric motors installed at each joint to drive them, the distance between the axis of the electric motor installed at the second joint and the axis of the electric motor installed at the first joint is generally far, so the inertial mass of the moving body to be driven by the electric motor at the first joint is large, making it difficult to achieve high acceleration and high speed.

The present invention provides a horizontal articulated robot to solve the technical problem that it is difficult to improve the speed and accuracy of horizontal articulated robots due to the limitations of the drive system and structure in the conventional technology.

In order to solve the above technical problems, one technical means adopted in the present invention is:
With the base,
a first arm connected to the base and having a first joint formed at a connection point with the base;
a first electric motor installed in the first joint and used to drive the first arm to rotate relative to the base;
a second arm connected to one end of the first arm remote from the base and having a second joint formed at a connection point with the first arm;
a second electric motor connected to the second arm via a transmission device and used to drive the second arm to rotate relative to the first arm;
The object of the present invention is to provide a horizontal articulated robot, characterized in that projections of the axis of the first motor and the axis of the second motor on a vertical plane at least partially overlap each other.

In one specific embodiment, the first motor and the second motor are installed so that their axes overlap.

In a specific embodiment, the first motor includes a first stator mounted on the base and a first rotor connected to the first arm and fitted outside the first stator, and the second motor includes a second stator mounted on the first arm and fixedly connected to the first stator, and a second rotor connected to the transmission device and fitted outside the second stator.

In a specific embodiment, the first motor includes a first stator mounted on the base and a first rotor connected to the first arm and fitted outside the first stator, and the second motor includes a second stator mounted on the first arm and fixedly connected to the first rotor, and a second rotor connected to the transmission device and fitted outside the second stator.

In a specific embodiment, the transmission device includes a first transmission wheel, a second transmission wheel, a first rigid transmission belt, and a second rigid transmission belt, the first transmission wheel is fitted outside the second rotor, the second transmission wheel is connected to the second arm, and the first rigid transmission belt and the second rigid transmission belt are connected to the first transmission wheel and the second transmission wheel by fixing members, respectively.

In a specific embodiment, the transmission device includes at least a first gear fitted to the outside of the second rotor and a second gear connected to the second arm, and is provided with a backlash-free gear assembly in which the first gear and the second gear mesh with each other.

In a specific embodiment, the transmission device includes a first synchronous wheel fitted to the outside of the second rotor, a second synchronous wheel connected to the second arm, and a synchronous belt connecting the first synchronous wheel and the second synchronous wheel.

In a specific embodiment, the first motor further includes a hollow shaft to form a first housing chamber, the second stator forms a second housing chamber that communicates with the first housing chamber, an opening is formed at one end of the second motor that is remote from the first motor, and the second housing chamber communicates with the outside through the opening.

In a specific embodiment, the horizontal articulated robot further includes a controller connected to the base, connected to the first electric motor via a first connection line passing through the first storage chamber, and connected to the second electric motor via a second connection line passing through the first storage chamber and the second storage chamber.

In a specific embodiment, the horizontal articulated robot further includes a first encoder connected to the first electric motor and connected to the controller via a third connection line passing through the first storage chamber, and a second encoder connected to the second electric motor and connected to the controller via a fourth connection line passing through the first storage chamber and the second storage chamber.

In a specific embodiment, the horizontal articulated robot further includes a third motor and a fourth motor installed in the second joint.

In a specific embodiment, a wire passage hole is provided in the second joint, a wire passage is provided inside the first arm, and the third motor and the fourth motor are connected to the controller via a fifth connecting line passing through the wire passage hole, the wire passage, and the first storage chamber.

In one specific embodiment, the second motor is fixedly connected to the base.

The horizontal articulated robot of the present invention comprises a base, a first arm connected to the base and having a first joint formed at a connection point with the base, a first electric motor installed in the first joint and used to drive the first arm to rotate relative to the base, a second arm connected to one end of the first arm remote from the base and having a second joint formed at a connection point with the first arm, and a second electric motor connected to the second arm via a transmission device and used to drive the second arm to rotate relative to the first arm, wherein the projections of the axis of the first motor of the first motor and the second motor at a vertical plane at least partially overlap, and the first electric motor By installing a first motor and a second motor to directly drive the first arm and the second arm, respectively, it is possible to omit the reducer, thereby avoiding the effect of the reducer on the accuracy, speed, cost, and drag torque of the horizontal articulated robot. Also, by installing the second motor so that the projection of the axis of the second motor on the vertical plane at least partially overlaps with the first motor, the distance between the axis of the first motor and the axis of the second motor can be reduced, reducing the output torque demand of the first motor, and further reducing the overall volume and mass of the horizontal articulated robot, contributing to the realization of high acceleration and high speed of the horizontal articulated robot.

In order to more clearly explain the technical means in the embodiments of the present application, the drawings necessary for describing the embodiments are briefly described below. However, it should be understood that the drawings described below are merely some embodiments of the present application, and a person skilled in the art may conceive of other drawings based on these drawings without any creative effort.

1 is a schematic diagram of a three-dimensional structure of one embodiment of a horizontal articulated robot of the present invention; 1 is a schematic diagram of a partial three-dimensional structure of one embodiment of a horizontal articulated robot of the present invention. FIG. 1 is a schematic diagram of a cross-sectional structure of one embodiment of a horizontal articulated robot of the present invention; 1 is a schematic diagram of the three-dimensional structure of a transmission device in one embodiment of a horizontal articulated robot of the present invention. FIG. FIG. 13 is a schematic diagram of a cross-sectional structure of another embodiment of a horizontal articulated robot of the present invention. FIG. 13 is a schematic diagram of a cross-sectional structure of another embodiment of a horizontal articulated robot of the present invention. FIG. 13 is a schematic diagram of a cross-sectional structure of another embodiment of a horizontal articulated robot of the present invention. FIG. 13 is a schematic diagram of a cross-sectional structure of another embodiment of a horizontal articulated robot of the present invention.

In the following, the technical means in the embodiments of the present invention will be clearly and completely described with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are not all the embodiments, but only some of the embodiments of the present invention. All other embodiments that a person skilled in the art can obtain without creative efforts based on the embodiments of the present invention shall fall within the scope of protection of the present invention.

The terms "first", "second" and the like in this application are for illustrative purposes only and should not be understood as indicating or implying a relative importance or a quantity of the indicated technical features. In the description of this application, unless otherwise expressly and specifically limited, "plurality" means at least two, e.g., two, three, etc. Furthermore, terms such as "comprises", "has", and any variations thereof are intended to be non-exclusive. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the steps or units listed, but may further include steps or units that are not listed, or may further include other steps or units that are specific to the process, method, product, or device. The term "and/or" is merely intended to describe the relationship between related objects, and means that three types of relationships can exist, for example, A and/or B may mean that A exists alone, A and B exist simultaneously, or B exists alone. Furthermore, the symbol "/" in this specification generally means that the related objects before and after are in an "or" relationship.

Referring to FIG. 1 to FIG. 3, one embodiment of the horizontal articulated robot 10 of the present invention includes a base 100, a first arm 200 connected to the base 100 and having a first joint 210 formed at a connection point with the base 100, a second arm 300 connected to one end of the first arm 200 remote from the base 100 and having a second joint 310 formed at a connection point with the first arm 200, a first electric motor 410 installed in the first joint 210 and used to drive the first arm 200 to rotate relative to the base 100, and a second electric motor 420 connected to the second arm 300 via a transmission device 500 and used to drive the second arm 300 to rotate relative to the first arm 200, and the projections of the axis of the first electric motor 410 on a vertical plane of the first electric motor 410 and the second electric motor 420 at least partially overlap.

Currently, horizontal articulated robots are generally driven by installing electric motors at each joint, for example, by combining a servo motor and a reducer. However, this driving method has the following problems. 1) There is a back gap, making it difficult to improve the accuracy of the horizontal articulated robot. 2) The maximum output torque of the reducer is limited, making it difficult to improve the speed of the horizontal articulated robot. 3) The cost of the reducer is high. 4) Due to the transmission method combining an electric motor and a reducer, the torque required to manually drag the horizontal articulated robot is large, which affects the manual drag teaching function of the horizontal articulated robot. However, in this embodiment, the first electric motor 410 and the second electric motor 420 are installed to directly drive the first arm 200 and the second arm 300, respectively, thereby eliminating the need for a reducer and avoiding the accuracy, speed, cost, and drag torque of the horizontal articulated robot 10 being affected by the limitations of the reducer.

In the current horizontal articulated robot driven by a direct drive motor, the output torque must be equal to the output torque generated by the drive method with a reducer. Compared with the original servo motor, the volume and mass of the direct drive motor are larger, which leads to an increase in the volume and mass of the entire horizontal articulated robot. In addition, the distance between the axis of the motor installed at the second joint and the axis of the motor installed at the first joint is far, and the inertial mass of the moving body to be driven by the motor at the first joint is large, making it difficult to achieve high acceleration and high speed. However, in this embodiment, the second motor 420 is installed so that the projection of the axis on the vertical plane at least partially overlaps with the first motor 410, thereby reducing the distance between the axis of the first motor 410 and the axis of the second motor 420, thereby reducing the output torque demand of the first motor 410, and further reducing the overall volume and mass of the horizontal articulated robot 10, which contributes to the realization of high acceleration and high speed of the horizontal articulated robot 10.

In this embodiment, the first electric motor 410 and the second electric motor 420 are installed so that their axes overlap, so that the output torque of the first electric motor 410 required for the first arm 200 on which the second electric motor 420 is mounted is smaller, and the overall volume and mass of the horizontal articulated robot 10 can be further reduced, contributing to realizing high acceleration and high speed of the horizontal articulated robot 10.

In this embodiment, the first electric motor 410 includes a first stator 411 installed on the base 100 and a first rotor 412 connected to the first arm 200 and fitted outside the first stator 411, and the second electric motor 420 includes a second stator 421 installed on the first arm 200 and fixedly connected to the first stator 411, and a second rotor 422 connected to the transmission device 500 and fitted outside the second stator 421. As a result, when the first electric motor 410 is started, the first arm 200 can be rotated relative to the base 100 in conjunction with the rotation of the first rotor 412 relative to the first stator 411, and at this time, since the second stator 421 is fixedly connected to the first stator 411, The second stator 421 does not move, and since the second motor 420 is not activated, the second rotor 422 does not move either, and therefore the second arm 300 is not driven. When the first arm 200 rotates relative to the base 100, it also rotates relative to the second arm 300. Therefore, when it is necessary to maintain the relative position between the second arm 300 and the first arm 200 unchanged, it is necessary to activate the second motor 420, which rotates the second rotor 422 relative to the second stator 421 in the same direction and angle as the first rotor 412, and then the second arm 300 is linked by the transmission device 500 to rotate in the same direction and angle as the first arm 200, thereby achieving compensation.

In this embodiment, in order to stabilize the overall structure of the horizontal articulated robot 10, the first stator 411 and the second stator 421 may be connected by a flange 430.

In other embodiments, the first stator 411 and the second stator 421 may be connected in other ways, such as by gluing or fastening, and are not limited here.

In this embodiment, the first rotor 412 is directly and fixedly connected to the first arm 200 so as to rotate the first arm 200 in conjunction with the first rotor 412.

In other embodiments, the first rotor 412 may be connected to the first arm 200 via a transmission device (not shown), which is not limited here.

Referring also to FIG. 4, in this embodiment, the transmission device 500 includes a first transmission wheel 510, a second transmission wheel 520, a first rigid transmission belt 530 and a second rigid transmission belt 540. The first transmission wheel 510 is fitted outside the second rotor 422, the second transmission wheel 520 is connected to the second arm 300, and the first rigid transmission belt 530 and the second rigid transmission belt 540 are respectively connected to the first transmission wheel 510 and the second transmission wheel 520 by the fixing member 550. The first rigid transmission belt 530 and the second rigid transmission belt By installing the drive 540 to transmit power between the first transmission wheel 510 and the second transmission wheel 520, power transmission between the second motor 420 and the second arm 300 can be realized, thereby reducing the installation position restrictions of the second motor 420 on the second arm 300, contributing to the realization of a reduction in the distance between the axis of the first motor 410 and the axis of the second motor 420, and avoiding backlash problems during the transmission process, improving the driving accuracy of the second motor 420, and further contributing to improving the overall accuracy of the horizontal articulated robot 10.

In this embodiment, the first rigid transmission belt 530 and the second rigid transmission belt 540 may be steel belts. In other embodiments, the first rigid transmission belt 530 and the second rigid transmission belt 540 may be other metal belts or rigid plastic belts, etc., and are not limited here.

In this embodiment, a bearing 521 may be installed between the second transmission wheel 520 and the second arm 300 to reduce friction between the second transmission wheel 520 and the second arm 300 and improve the service life of the transmission device 500.

In another specific embodiment, the transmission device 500 may include a first synchronous wheel (not shown) fitted outside the second rotor 422, a second synchronous wheel (not shown) connected to the second arm 300, and a synchronous belt (not shown) connecting the first synchronous wheel and the second synchronous wheel. When the second rotor 422 rotates, the first synchronous wheel rotates accordingly, transmitting and moving the synchronous belt, and further interlocking the second synchronous wheel to rotate the second arm 300 in interlocking. The first synchronous wheel, the second synchronous wheel, and the synchronous belt can realize the transmission between the second motor 420 and the second arm 300, thereby reducing the installation position restriction of the second motor 420 on the second arm 300 and contributing to the realization of a reduction in the distance between the axis of the first motor 410 and the axis of the second motor 420.

In this embodiment, the first motor 410 further includes a hollow shaft 413 to form a first housing chamber 414, the second stator 421 forms a second housing chamber 423 that communicates with the first housing chamber 414, and an opening 424 is formed at one end of the second motor 420 that is remote from the first motor 410, and the second housing chamber 423 communicates with the outside through the opening 424. As a result, heat generated inside the first motor 410 and the second motor 420 can be transferred to the outside through the first housing chamber 414 and the second housing chamber 423, thereby achieving effective heat dissipation, which contributes to improving the service life of the first motor 410 and the second motor 420 and contributing to realizing high-speed operation of the first motor 410 and the second motor 420.

In this embodiment, the second rotor 422 is covered with an end cover 440, and an opening 424 can be formed in the end cover 440 to provide communication between the second storage chamber 423 and the outside. Furthermore, by installing the end cover 440, it is possible to provide a waterproof and dustproof function, and it is possible to improve the service life of the second electric motor 420.

In this embodiment, the horizontal articulated robot 10 may further include a controller 600 connected to the base 100, connected to the first electric motor 410 via a first connection line 610 passing through the first storage chamber 414, and connected to the second electric motor 420 via a second connection line 620 passing through the first storage chamber 414 and the second storage chamber 423. Compared to the solid hollow shaft motors currently used in horizontal articulated robots, in which the connection wires are wrapped around the outside of the motors, complicating the internal structure of the horizontal articulated robot and are prone to interfering with other components, in this embodiment, the first connection wire 610 and the second connection wire 620 between the first motor 410 and the second motor 420 and the controller 600 pass directly through the first motor 410 and the second motor 420, making the internal structure of the horizontal articulated robot 10 simpler and making the first connection wire 610 and the second connection wire 620 less likely to interfere with other components, and enabling the horizontal articulated robot 10 to have higher reliability.

In this embodiment, the horizontal articulated robot 10 further includes a first encoder 450 connected to the first electric motor 410 and connected to the controller 600 via the third connection line 630 passing through the first storage chamber 414, and a second encoder 460 connected to the second electric motor 420 and connected to the controller 600 via the fourth connection line 640 passing through the first storage chamber 414 and the second storage chamber 423. By installing the first encoder 450 to be combined with the direct drive method of the first electric motor 410 and installing the second encoder 460 to be combined with the direct drive method of the second electric motor 420, This improves the driving accuracy of the two electric motors 420, and further improves the overall operating accuracy of the horizontal articulated robot 10. Also, by connecting the first encoder 450 and the second encoder 460 to the controller 600 with connection lines that pass through the first storage chamber 414 and the second storage chamber 423, it is possible to prevent the connection lines from wrapping around the outside of the motors and complicating the internal structure of the horizontal articulated robot 10, making the internal structure of the horizontal articulated robot 10 simpler, and making it less likely that the third connection line 630 and the fourth connection line 640 will interfere with other components, resulting in higher reliability of the horizontal articulated robot 10.

In this embodiment, both the first encoder 450 and the second encoder 460 may be annular encoders, the first encoder 450 is fitted to the outside of the hollow shaft 413, and the second encoder 460 is installed on the second stator 421, which can avoid blocking the heat dissipation airflow flowing through the first storage chamber 414 and the second storage chamber 423, and the heat dissipation airflow can have a heat dissipation effect on the first encoder 450 and the second encoder 460, and can further improve the reliability and stability of the operation of the first encoder 450 and the second encoder 460.

In another embodiment, the first encoder 450 and the second encoder 460 may be solid encoders, with at least a portion of the first encoder 450 being installed in the first housing chamber 414 and at least a portion of the second encoder 460 being installed in the second housing chamber 423, thereby allowing the first encoder 450 and the second encoder 460 to dissipate heat when the heat dissipation airflow flows through the first housing chamber 414 and the second housing chamber 423, and further improving the reliability and stability of the operation of the first encoder 450 and the second encoder 460.

In this embodiment, the first electric motor 410 further includes a first bearing 415 that is installed between the hollow shaft 413 and the first rotor 412 to reduce friction between the hollow shaft 413 and the first rotor 412, thereby improving the service life of the first electric motor 410 and preventing the communication between the first housing chamber 414 and the second housing chamber 423 from being blocked.

In this embodiment, the first motor 410 may further include a second bearing 416 that is installed between the first base 417 and the first rotor 412 of the first motor 410 to reduce friction between the first base 417 and the first rotor 412 and improve the service life of the first motor 410, and also firmly connects the first base 417 to the heavy first stator 411 to overcome the overturning moment and further stabilize the structure of the first motor 410.

In this embodiment, the base 100 may further be formed with a through hole (not shown) that communicates with the first storage chamber 414, so that the heat dissipation gas in the first storage chamber 414 can further flow to the outside through the through hole of the base 100, further improving the heat dissipation effect. In addition, by installing the second bearing 416 between the first base part 417 and the first rotor 412, it is possible to avoid blocking the release of the heat dissipation airflow from the base 100.

In this embodiment, the second motor 420 may further include a third bearing 425 that is installed between the second stator 421 and the second rotor 422 to reduce friction between the second stator 421 and the second rotor 422, thereby improving the service life of the second motor 420 and avoiding blocking of communication between the second housing chamber 423 and the outside.

In this embodiment, the second motor 420 may further include a fourth bearing 426 that is installed between the second base 427 and the second rotor 422 of the second motor 420 to reduce friction between the second base 427 and the second rotor 422 and improve the service life of the second motor 420, and also firmly connects the second base 427 to the heavy second stator 421 to overcome the overturning moment and further stabilize the structure of the second motor 420.

In this embodiment, the horizontal articulated robot 10 may further include a third electric motor 470, a fourth electric motor 480 and a shaft body 320, where the third electric motor 470 and the fourth electric motor 480 are installed within the second joint 310, the shaft body 320 is installed at one end of the second arm 300 remote from the first arm 200, and the third electric motor 470 and the fourth electric motor 480 are each connected to the shaft body 320 and are used to drive the rotation and vertical movement of the shaft body 320, respectively. Compared to current horizontal articulated robots in which the third and fourth motors for driving the shafts are installed at one end of the second arm away from the first arm, in this embodiment, the third and fourth motors 470 and 480 are installed in the second joint 310, thereby reducing the distance between the axis of the third and fourth motors 470 and 480 and the axis of the first and second motors 410 and 420, thereby reducing the output torque demand of the first and second motors 410 and 420, thereby reducing the overall volume and mass of the horizontal articulated robot 10, and further contributing to realizing high acceleration and high speed of the horizontal articulated robot 10.

In this embodiment, a wire passage hole 311 is provided in the second joint 310, a wire passage 220 is provided inside the first arm 200, and the third motor 470 and the fourth motor 480 are connected to the controller 600 via the fifth connecting wire 650 through the wire passage hole 311, the wire passage 220 and the first storage chamber 414, thereby preventing the fifth connecting wire 650 from wrapping around the outside of the first motor 410 and complicating the internal structure of the horizontal articulated robot 10, making the internal structure of the horizontal articulated robot 10 simpler, making the fifth connecting wire 650 less likely to interfere with other components, and increasing the reliability of the horizontal articulated robot 10.

In this embodiment, the third motor 470 and the fourth motor 480 may be connected to the shaft body 320 via a transmission device (not shown). For the structure of the transmission device, please refer to the transmission device 500 described above, and a detailed description will be omitted here.

In another embodiment, the third motor 470 and the fourth motor 480 may be installed on the first arm 200, thereby further reducing the distance between the axis of the third motor 470 and the axis of the fourth motor 480 and the axis of the first motor 410 and the axis of the second motor 420, thereby reducing the output torque demand of the first motor 410 and the second motor 420, thereby further reducing the overall volume and mass of the horizontal articulated robot 10, and further contributing to realizing high acceleration and high speed of the horizontal articulated robot 10.

Referring to FIG. 5, another embodiment of the horizontal articulated robot 10 of the present invention includes a base 100, a first arm 200, a second arm 300, a first electric motor 710, and a second electric motor 720. Here, for the structures of the base 100, the first arm 200, and the second arm 300, please refer to the embodiment of the horizontal articulated robot 10 described above, and detailed description will be omitted here.

This embodiment differs from the above embodiment in that the first electric motor 710 includes a first stator 711 installed on the base 100 and a first rotor 712 connected to the first arm 200 and fitted outside the first stator 711, and the second electric motor 720 includes a second stator 721 installed on the first arm 200 and fixedly connected to the first rotor 712, and a second rotor 722 connected to the transmission device 500 and fitted outside the second stator 721. As a result, when the first electric motor 710 is started, the first stator 711 of the first rotor 712 By rotating the first arm 200 relative to the base 100, the second stator 721 rotates with the first rotor 712 because it is fixedly connected to the first rotor 712 at this time, and since the second motor 720 is not started, the second rotor 722 also rotates with it, so the second arm 300 is rotated with the same direction and angle as the first arm 200 by the transmission device 500, and the second arm 300 maintains its relative position with respect to the first arm 200 without changing.

In this embodiment, in order to stabilize the overall structure of the horizontal articulated robot 10, the second stator 721 and the first rotor 712 may be connected by a flange 730.

In other embodiments, the second stator 721 and the first rotor 712 may be connected in other ways, such as by gluing or fastening, and are not limited here.

Referring to FIG. 6, another embodiment of the horizontal articulated robot 10 of the present invention includes a base 100, a first arm 200, a second arm 300, a first electric motor 810, and a second electric motor 820. Here, for the structures of the base 100, the first arm 200, and the second arm 300, please refer to the embodiment of the horizontal articulated robot 10 described above, and detailed description will be omitted here.

This embodiment differs from the above embodiment in that the second motor 820 is fixedly connected to the base 100. Specifically, the base 100 includes a first mounting plate 110 and a second mounting plate 120 that are spaced apart along the axial direction of the first motor 810. The first motor 810 includes a first stator 811 installed on the first mounting plate 110 and a first rotor 812 connected to the first arm 200 and fitted outside the first stator 811, and the second motor 820 includes a second stator 821 installed on the second mounting plate 120 and a second rotor 822 connected to the transmission device 500 and fitted outside the second stator 821. In this embodiment, the method in which the first electric motor 810 and the second electric motor 820 drive the first arm 200 and the second arm 300 is similar to the method in which the first electric motor 410 and the second electric motor 420 drive the first arm 200 and the second arm 300 in the above embodiment, and a detailed description will be omitted here.

In this embodiment, by connecting the second electric motor 820 to the base 100, the mass carried by the first electric motor 810 can be further reduced, and the output torque demand of the first electric motor 810 can be further reduced, thereby reducing the overall volume and mass of the horizontal articulated robot 10 and contributing to realizing high acceleration and high speed of the horizontal articulated robot 10.

In this embodiment, the axes of the first electric motor 810 and the second electric motor 820 overlap, and the projections of the axis of the first electric motor 810 on the vertical plane of the first electric motor 810 and the second electric motor 820 are all overlapped, which makes it possible to further stabilize the center of gravity of the horizontal articulated robot 10 and to make the entire structure more stable.

Referring to FIG. 7, in another specific embodiment, the axes of the first motor 810 and the second motor 820 are installed in parallel, the projections of the axis of the first motor 810 on the vertical plane of the first motor 810 and the second motor 820 partially overlap, and the distance between the second motor 820 and the second joint 310 is closer, so that the distance to be transmitted by the transmission device 500 is shorter and the possibility of error occurrence is smaller.

Referring to FIG. 6, in this embodiment, the transmission device 500 transmits power using a rigid transmission belt. For the specific structure, please refer to the embodiment of the horizontal articulated robot 10 described above, and a detailed description will be omitted here.

Referring to FIG. 8, in another specific embodiment, the transmission device 500 comprises a backlash-free gear assembly including at least a first gear 560 and a second gear 570, the first gear 560 and the second gear 570 have the same tooth thickness, the same installation height, and are seamlessly meshed to realize backlash-free transmission. The first gear 560 is fitted outside the second rotor 822, and the second gear 570 is connected to the second arm 300. The first gear 560 and the second gear 570 mesh with each other. When the second rotor 822 rotates, the first gear 560 rotates accordingly. The second motor 820 rotates, and the second arm 300 can be rotated in conjunction with the second gear 570. The backlash-free gear assembly realizes transmission between the second motor 820 and the second arm 300, thereby reducing the installation position restriction of the second motor 820 on the second arm 300, contributing to the realization of a reduction in the distance between the axis of the first motor 810 and the axis of the second motor 820, and avoiding backlash problems during the transmission process, improving the driving accuracy of the second motor 820, and contributing to improving the overall accuracy of the horizontal articulated robot 10.

The above is merely an embodiment of the present application and does not limit the scope of the claims of the present application. Any equivalent configuration or equivalent flow conversion made using the contents of the specification and drawings of the present application, or any direct or indirect application thereof to other related technical fields, are similarly included in the scope of the claims of the present application.

Claims (9)

With the base,
a first arm connected to the base and having a first joint formed at a connection point with the base;
a first electric motor installed in the first joint and used to drive the first arm to rotate relative to the base;
a second arm connected to one end of the first arm remote from the base and having a second joint formed at a connection point with the first arm;
a second electric motor connected to the second arm via a transmission device and used to drive the second arm to rotate relative to the first arm;
a projection of an axis of the first motor and a projection of the second motor on a vertical plane at least partially overlaps with each other;
The base includes a first mounting plate and a second mounting plate,
the first motor includes a first stator mounted on the first mounting plate and a first rotor connected to the first arm and fitted around the outside of the first stator; the second motor includes a second stator mounted on the second mounting plate and a second rotor connected to the transmission device and fitted around the outside of the second stator ;
a first electric motor further including a hollow shaft to form a first accommodation chamber, a second stator forming a second accommodation chamber communicating with the first accommodation chamber, an opening being formed at one end of the second electric motor remote from the first electric motor, and the second accommodation chamber communicating with the outside via the opening . The horizontal articulated robot according to claim 1, characterized in that the first electric motor and the second electric motor are installed so that their axes overlap. The horizontal articulated robot according to claim 1 or 2, characterized in that the transmission device comprises a first transmission wheel, a second transmission wheel, a first rigid transmission belt, and a second rigid transmission belt, the first transmission wheel is fitted outside the second rotor, the second transmission wheel is connected to the second arm, and the first rigid transmission belt and the second rigid transmission belt are connected to the first transmission wheel and the second transmission wheel by fixing members, respectively. The horizontal articulated robot according to claim 1 or 2, characterized in that the transmission device includes at least a first gear fitted to the outside of the second rotor and a second gear connected to the second arm, and is provided with a backlash-free gear assembly in which the first gear and the second gear mesh with each other. The horizontal articulated robot according to claim 1 or 2, characterized in that the transmission device comprises a first synchronous wheel fitted to the outside of the second rotor, a second synchronous wheel connected to the second arm, and a synchronous belt connecting the first synchronous wheel and the second synchronous wheel. 2. The horizontal articulated robot according to claim 1, further comprising a controller connected to the base, passing through the first storage chamber via a first connection line and connected to the first electric motor, and passing through the first storage chamber and the second storage chamber via a second connection line and connected to the second electric motor. 7. The horizontal articulated robot according to claim 6, further comprising: a first encoder connected to the first electric motor and connected to the controller via a third connection line passing through the first accommodation chamber; and a second encoder connected to the second electric motor and connected to the controller via a fourth connection line passing through the first accommodation chamber and the second accommodation chamber. 2. The horizontal articulated robot according to claim 1 , further comprising a third motor and a fourth motor disposed within the second joint. Further comprising a third electric motor and a fourth electric motor installed in the second joint,
7. The horizontal articulated robot according to claim 6, wherein a wire passing hole is provided in the second joint, a wire passage is provided inside the first arm, and the third electric motor and the fourth electric motor are connected to the controller via a fifth connecting line passing through the wire passing hole, the wire passage and the first accommodating chamber.

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