Double-encoder joint actuator and robot

Abstract

The invention provides a double-encoder joint actuator and a robot, and relates to the field of robots. The joint actuator comprises a motor, a speed reducer, a hollow rotating shaft and a controller; the motor comprises a motor rotor and a motor stator; the speed reducer comprises a speed reducer output end; the joint actuator is characterized in that the joint actuator comprises a first encoder which comprises a first permanent magnet fixed to a motor rotor and at least one first magnetic sensor; the first magnetic sensor and the first permanent magnet are oppositely arranged; the second encoder comprises a second permanent magnet located in the middle of the first permanent magnet and a second magnetic sensor; the second permanent magnet rotates along with the output end of the speed reducer through the transmission mechanism; and the second magnetic sensor and the second permanent magnet are oppositely arranged. By optimizing the position relation of the double encoders, the axial length of the joint actuator is reduced, and the stability and the measurement precision of the joint actuator are improved.

Description

Technical Field

[0001] The present disclosure relates to the field of robots, and in particular to a dual-encoder joint actuator and a robot. Background Art

[0002] In the dual-encoder joint actuator in the prior art, two encoders respectively obtain the angle information of the encoder actuator motor rotor and the actuator reducer output end. In order to avoid interference between the two encoders, the two encoders are usually staggered up and down along the motor axis in space. The dual encoder needs to occupy the space of two encoders on the motor axis. This layout objectively causes the axial length of the entire device to be too long. The excessive axial length makes it impossible to use it in the narrow space of the robot joint. In addition, the two sensors arranged up and down need to be connected to the controller through additional cables. The circuit instability of the joint actuator is also increased due to the additional cables.

[0003] In summary, although the dual-encoder joint actuator in the prior art is reasonable in terms of functional realization, it has obvious limitations in terms of the spatial layout and circuit stability of the joint actuator. Summary of the invention

[0004] The present disclosure provides a dual-encoder joint actuator.

[0005] According to a first aspect, a dual encoder joint actuator is provided, comprising a motor, a reducer, a hollow shaft, and a controller; the motor comprises a motor rotor and a motor stator; the reducer comprises a reducer output end; and the joint actuator comprises:

[0006] A first encoder comprises a first permanent magnet fixed to the motor rotor, and at least one first magnetic sensor; the first magnetic sensor is arranged opposite to the first permanent magnet;

[0007] The second encoder includes a second permanent magnet located in the middle of the first permanent magnet, and a second magnetic sensor; the second permanent magnet rotates with the output end of the reducer through a transmission mechanism; the second magnetic sensor and the second permanent magnet are arranged opposite to each other.

[0008] Optionally, the first permanent magnet is a magnetic ring arranged around the central axis of the hollow rotating shaft, the first permanent magnet is fixedly connected to the motor rotor via a first permanent magnet connector, and the first permanent magnet rotates synchronously with the rotation of the motor rotor.

[0009] Optionally, the first magnetic sensor is a Hall sensor, and the number of the Hall sensors is at least two.

[0010] Optionally, the first magnetic sensor is a magnetic encoder.

[0011] Optionally, when there are multiple first magnetic sensors, the multiple first magnetic sensors are arranged around the hollow rotating shaft.

[0012] Optionally, the second permanent magnet is a permanent magnet located on the central axis of the hollow rotating shaft; and the second magnetic sensor is located on the central axis of the hollow rotating shaft.

[0013] Optionally, the second permanent magnet is a magnetic ring arranged around the central axis of the hollow rotating shaft; and the second magnetic sensor is arranged around the hollow rotating shaft.

[0014] Optionally, the transmission mechanism is disposed in the hollow rotating shaft.

[0015] Optionally, the transmission mechanism includes a transmission rod; the transmission rod is connected to the output end of the reducer, and the transmission rod rotates as the output end of the reducer rotates; the transmission rod is connected to the second permanent magnet, and the second permanent magnet rotates as the transmission rod rotates.

[0016] Optionally, the transmission rod rotates around the central axis of the hollow shaft.

[0017] Optionally, the transmission mechanism further includes a first connecting member; the first connecting member is respectively connected to the transmission rod and the output end of the reducer; the transmission mechanism further includes a second connecting member; the second connecting member is connected to the transmission rod and the second permanent magnet.

[0018] Optionally, in the second encoder, the number of the second permanent magnet is one, the number of the second magnetic sensor is one, and the second magnetic sensor is mounted on the controller.

[0019] Optionally, in the second encoder, the second permanent magnet is a magnetic ring arranged around the central axis of the hollow rotating shaft, and the number of the second magnetic sensor is at least one.

[0020] Optionally, the joint actuator further comprises: a third encoder;

[0021] The third encoder includes: a third permanent magnet located in the middle of the second permanent magnet, and a third magnetic sensor mounted on the controller.

[0022] According to another aspect of the present disclosure, a robot is provided, comprising the joint actuator as described above.

[0023] The dual encoder joint actuator and robot provided by the embodiment of the present disclosure bring significant beneficial effects. First, by optimizing the positional relationship of the dual encoders, the second permanent magnet of the second encoder is located between the first permanent magnet of the first encoder, so that the second encoder and the first encoder can share the same space in the axial direction, effectively shortening the length of the two encoders in the axial direction. The dual encoder joint actuator can be installed in a narrow space. This is crucial for many application scenarios with strict requirements on space dimensions. In equipment such as precision instruments and small robots, the reduction in axial length means that the equipment can be installed and operated in a smaller space, improving the adaptability and flexibility of the equipment, and also helping to improve the overall compactness and aesthetics of the equipment. Secondly, this design method also optimizes the installation structure of the sensor. In traditional designs, the distance between the controller and other components is far, which not only increases the axial length, but also may introduce unstable factors such as electromagnetic interference due to the presence of cables. However, by arranging the dual encoders in the same space, the integration of the controller and other components is greatly improved in this solution, effectively avoiding the potential risks brought by cable connection, and thus significantly improving the stability of the circuit. In summary, this technical solution has significant technical advantages in optimizing spatial layout and improving the stability of joint actuator circuits, and has high practical value and innovation.

[0024] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present disclosure, nor is it intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings are used to better understand the present solution and do not constitute a limitation of the present disclosure.

[0026] Figure 1 It is a side view structural schematic diagram of a dual encoder joint actuator in the prior art;

[0027] Figure 2 is a schematic side view of the structure of the dual encoder joint actuator according to the first embodiment of the present disclosure;

[0028] Figure 3 is a schematic diagram of the three-dimensional structure of the dual-encoder joint actuator according to the second embodiment of the present disclosure;

[0029] Figure 4 is a cross-sectional schematic diagram of a dual-encoder joint actuator according to the second embodiment of the present disclosure;

[0030] Figure 5 It is a three-dimensional structural diagram of a dual-encoder joint actuator in which a magnetic sensor and a controller are integrated according to the third embodiment of the present disclosure;

[0031] Figure 6 is a cross-sectional schematic diagram of a dual-encoder joint actuator in which a magnetic sensor and a controller are integrally arranged according to the third embodiment of the present disclosure;

[0032] Figure 7 is a schematic side view of the structure of the dual encoder joint actuator according to the fourth embodiment of the present disclosure;

[0033] Figure 8 is a top view structural diagram of a dual encoder joint actuator according to the second embodiment of the present disclosure;

[0034] Fig. 9 It is a schematic diagram of the top view structure of the dual encoder joint actuator in the fourth embodiment of the present disclosure.

[0035] Fig.10 It is a schematic diagram of the top view structure of the three-encoder joint actuator in the fourth embodiment of the present disclosure. DETAILED DESCRIPTION

[0036] The following is a description of exemplary embodiments of the present disclosure in conjunction with the accompanying drawings, including various details of the embodiments of the present disclosure to facilitate understanding, which should be considered as merely exemplary. Therefore, it should be recognized by those of ordinary skill in the art that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the present disclosure. Similarly, for the sake of clarity and conciseness, descriptions of well-known functions and structures are omitted in the following description.

[0037] In the description of the present disclosure, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0038] It should be noted that the block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities.

[0039] like Figure 1 As shown, the dual encoder joint actuator 100 in the prior art includes a reducer 101, a hollow shaft 102, a motor 103, a first encoder 104, a second encoder 105, and a controller 106. The reducer 101 includes a reducer output end and a reducer body; the motor 103 includes a motor stator and a motor rotor; the first encoder 104 includes a first permanent magnet and a first magnetic sensor; the second encoder 105 includes a second permanent magnet and a second magnetic sensor. The first encoder 104 measures the first rotation direction, real-time angle, angular velocity, etc. of the motor rotor; the second encoder 105 measures the second rotation direction, real-time angle, angular velocity, etc. of the reducer output end. The first encoder 104 and the second encoder 105 are connected to the controller 106 respectively.

[0040] The encoder is usually connected to the rotating shaft of the joint actuator. For example, the first encoder 104 for detecting the angle of the motor rotor is connected to the rotating shaft of the motor rotor, and the second encoder 105 for detecting the output end of the reducer is connected to the output end of the reducer. The encoder obtains the rotation information of the joint by detecting the angular displacement of the rotating shaft. For example, in a traditional industrial robot joint, the permanent magnet of the encoder rotates with the joint shaft, while the detection elements such as the magnetic sensor are fixed in other positions, and the rotation direction, angle, angular velocity and other information of the shaft are determined by detecting the magnetic field changes of the permanent magnet.

[0041] In the traditional layout where both encoders need a certain space to accommodate the rotational motion, in order to avoid interference between the two encoders, the first encoder 104 and the second encoder 105 are spatially staggered in the direction of the central axis Z. This significantly increases the axial length of the entire dual-encoder joint actuator 100. In some compact robot joint spaces, this layout causes the axial length of the actuator to exceed the space that can be accommodated inside the joint, resulting in the inability to be properly installed in the narrow space of the robot joint.

[0042] Moreover, in the traditional layout, the controller 106 is generally located outside the dual encoders. If the staggered first encoder 104 and the second encoder 105 need to be connected to the controller 106 outside, at least one of them needs to be connected to the controller 106 via a cable. Figure 1 In the illustrated scenario, the controller 106 is outside the second encoder 105, and the second encoder 105 is between the controller 106 and the first encoder 104. Therefore, the second magnetic sensor of the second encoder 105 cannot be directly mounted on the controller 106. That is, at least the second magnetic sensor needs to be connected to the controller 106 through a line. When the robot joints move frequently, the cable connection may be loose, resulting in unstable signal transmission.

[0043] In order to solve the above technical problems, the present disclosure proposes a dual-encoder joint actuator.

[0044] It is understandable that the various embodiments covered by the present disclosure are described and explained in depth from the unique perspectives and different dimensions of the overall technical solution. In actual application scenarios, based on diverse needs, the technical solutions involved in different embodiments can be flexibly and freely combined according to specific circumstances. This combination is not a simple patchwork, but through careful integration and adaptation, a more comprehensive, efficient and comprehensive technical architecture that meets actual business needs is constructed, further expanding the applicability and feasibility of the disclosed technical solution in different fields and different situations.

[0045] Embodiment 1

[0046] like Figure 2 As shown, a dual encoder joint actuator 200 in one embodiment of the present disclosure includes a reducer 201, a hollow shaft 202, a motor 203, a first encoder 204, a second encoder 205, and a controller 206. The reducer 201 includes a reducer output terminal and a reducer body; the motor 203 includes a motor stator and a motor rotor; the first encoder 204 includes a first permanent magnet and a first magnetic sensor; the second encoder 205 includes a second permanent magnet and a second magnetic sensor. The first encoder 204 measures the first rotation direction, real-time angle, angular velocity, etc. of the motor rotor; the second encoder 205 measures the second rotation direction, real-time angle, angular velocity, etc. of the reducer output terminal 201A.

[0047] like Figure 2 As shown, the first encoder 204 is hollow, for example, a first encoder 204 composed of a magnetic ring and a plurality of annularly arranged magnetic sensors. The second encoder 205 is arranged on the central axis Z of the hollow shaft 202 and is located in the middle of the first encoder 204. Therefore, the first encoder 204 and the second encoder 205 can be arranged in the same space in the axial direction without misalignment, thereby shortening the axial length of the joint actuator.

[0048] Embodiment 2

[0049] like Figure 3 Shown is a schematic diagram of the three-dimensional structure of the dual encoder joint actuator.

[0050] The dual encoder joint actuator 200 includes a reducer 201, a hollow shaft 202, a motor 203, a first encoder 204, a second encoder 205, a controller 206, a housing 207, and a transmission rod 208. The reducer 201 includes a reducer output end 201A and a reducer body 201B; the motor 203 includes a motor rotor and a motor stator.

[0051] The output end 201A of the reducer is connected to the transmission rod 208. The transmission rod 208 is inserted into the hollow shaft 202, and transmits the rotation of the output end 201A of the reducer to the second encoder 205 located at the actuator motor side for measurement.

[0052] The first encoder 204 measures the first rotation direction, real-time angle, angular velocity, etc. of the motor rotor. The first encoder 204 includes a first permanent magnet 204A, a first magnetic sensor 204B, a first permanent magnet connector 204C, and a first magnetic sensor circuit board 204D. The first permanent magnet 204A is a magnetic ring. The first permanent magnet 204A and the first permanent magnet connector 204C are connected, and the specific connection method can be bonding, clamping, etc.

[0053] like Figure 3 As shown, the first magnetic sensor 204B can specifically be a Hall sensor. The number of the first magnetic sensors 204B is usually two, three, or four or more. In order to fix the first magnetic sensor 204B at a position corresponding to the magnetic ring 204A, the first magnetic sensor 204B is fixed in position by a first magnetic sensor circuit board 204D. Optionally, the number of first magnetic sensors 204B can be the same as the number of first magnetic sensor circuit boards 204D, that is, one first magnetic sensor 204B is fixed on one first magnetic sensor circuit board 204D. Optionally, multiple first magnetic sensors 204B can be fixed on one first magnetic sensor circuit board 204D. Figure 3 In a specific embodiment shown in the figure, two first magnetic sensors 204B are fixed on a first magnetic sensor circuit board 204D; a total of two first magnetic sensor circuit boards 204D are used to fix all four first magnetic sensors 204B. Optionally, the first magnetic sensors 204B can be arranged along a ring at equal distances; optionally, the first magnetic sensors 204B can be arranged along a ring in other distribution modes, such as Figure 3 As shown, among the four first magnetic sensors 204B, two are grouped together, and the two first magnetic sensors 204B in the group are close to each other, so that they are convenient to be installed on the same first magnetic sensor circuit board 204D.

[0054] like Figure 8 As shown, the first magnetic sensor 204B can be a magnetic encoder. The number of the first magnetic sensors 204B is usually one, two, or three or more. In order to fix the first magnetic sensor 204B at a position corresponding to the magnetic ring 204A, the first magnetic sensor 204B can be fixed by a circuit board. Optionally, the first magnetic sensors 204B can be arranged along the ring at equal distances, such as Figure 8 The four shown are arranged at 90 degree intervals; optionally, the first magnetic sensors may also be arranged in other distribution patterns.

[0055] The second encoder 205 includes a second permanent magnet 205A and a second magnetic sensor 205B (see Figure 4 ). Optionally, the second permanent magnet 205A is a cylindrical permanent magnet. Optionally, the second permanent magnet 205A can be a permanent magnet of other shapes. The second encoder 205 measures the second rotation direction, real-time angle, angular velocity, etc. of the reducer output terminal 201A.

[0056] The radius of the second permanent magnet 205A is less than or equal to the inner diameter of the first permanent magnet 204A, and the second permanent magnet 205A can be completely accommodated in the middle of the first permanent magnet 204A, that is, the second permanent magnet 205A can be installed together with the first permanent magnet 204A. Therefore, the second permanent magnet 205A and the first permanent magnet 204A can be arranged in the same space in the axial direction without misalignment, thereby shortening the axial length of the joint actuator.

[0057] like Figure 3 As shown, the first magnetic sensor 204B passes through the first magnetic sensor circuit board 204D, and the first magnetic sensor circuit board 204D is arranged on the motor 203. The second magnetic sensor 205B is directly arranged on the controller 206. That is, the first magnetic sensor 204B and the second magnetic sensor 205B are designed separately, which is convenient for maintenance and replacement.

[0058] Regardless of whether the first magnetic sensor 204B is separately disposed on the controller 206, the first magnetic sensor 204B is disposed close to or in close proximity to the controller 206, and there is no need to set an excessively long cable between the second magnetic sensor 205B and the controller 206. The second magnetic sensor 205B is directly disposed on the controller 206, and there is no need to set a cable between it and the controller 206, thereby improving the circuit stability of the joint actuator.

[0059] Furthermore, the second magnetic sensor 205B is disposed on the central axis Z of the hollow shaft 202 and is located in the middle of the first magnetic sensor 204B. Therefore, the second magnetic sensor 205B and the first magnetic sensor 204B will not interfere with each other in space, thereby shortening the axial length of the joint actuator.

[0060] like Figure 3 As shown, the first permanent magnet 204A is a magnetic ring, and the first magnetic sensor 204B is arranged at the outer ring position outside the magnetic ring. The first permanent magnet 204A and the first magnetic sensor 204B are arranged along the ring, and are located at the outer ring positions of the second permanent magnet 205A and the second magnetic sensor 205B, so these components will not interfere with each other in space. In general, the first encoder and the second encoder can be arranged without axial misalignment, thereby shortening the axial length of the joint actuator.

[0061] Figure 3 The number of the first magnetic sensors 204B shown in the figure can be any positive integer such as 1, 2, 3, 4, 5, etc., based on the standard that the magnetic sensors can be reasonably arranged on the joint actuator.

[0062] When the number of the first magnetic sensors is greater than one, the distances between any two first magnetic sensors 204B and the central axis Z may be the same or different.

[0063] When the first magnetic sensor 204B is a Hall sensor, the number of the Hall sensors is at least two. Two or more Hall sensors form a group and cooperate to obtain a measurement result. When a group of multiple Hall sensors are at the same distance from the central axis Z, the two are arranged on an arc of the same radius. Multiple groups of Hall sensors can be arranged on arcs of the same radius or different radii. The angles between multiple Hall sensors can be the same or different. The positions of multiple groups of Hall sensors can be the same or different. The radius of the arcs between multiple groups of Hall sensors can be the same or different. This arrangement can improve the accuracy and redundancy of the detection of the rotation angle of the motor rotor. If one group of Hall sensors fails, the Hall sensors of other groups can still provide enough information to ensure normal measurement, thereby improving the overall reliability.

[0064] When the first magnetic sensor 204B is a magnetic encoder, the number of the magnetic encoder is at least one. Figure 8 As shown, four magnetic encoders are used. One magnetic encoder can measure and obtain the measurement result alone. Multiple magnetic encoders can be arranged on arcs of the same radius or different radii. The positions of multiple magnetic encoders can be the same or different. The radius of the arcs of multiple magnetic encoders can be the same or different. This arrangement can improve the accuracy and redundancy of the detection of the rotation angle of the motor rotor. If one of the magnetic encoders fails, the other magnetic encoders can still provide enough information to ensure normal measurement, thereby improving the overall reliability.

[0065] In one embodiment, the first magnetic sensors 204B are arranged at the same fixed angle interval. When arranged at the same fixed angle interval, when the motor rotor rotates, each first magnetic sensor 204B can detect the magnetic field change of the first permanent magnet 204A. This arrangement can improve the accuracy and redundancy of the detection of the rotation angle of the motor rotor.

[0066] In another embodiment, the spacing angles of the first magnetic sensors 204B may not be exactly the same. This arrangement can meet special magnetic field detection requirements or better layout of magnetic sensors in a limited installation space. When the robot joint performs complex movements, this non-uniform spacing arrangement may provide more accurate magnetic field change detection under certain specific movement postures, thereby improving the accuracy of joint control.

[0067] When arranged at the same fixed angle interval, the plurality of first magnetic sensors 204B can still be distributed on arcs at the same distance from the central axis Z, or on arcs at different distances from the central axis Z. When arranged at non-fixed angle intervals, the plurality of first magnetic sensors 204B can still be distributed on arcs at the same distance from the central axis Z, or on arcs at different distances from the central axis Z.

[0068] Regardless of the setting of the interval angles between the multiple first magnetic sensors 204B, the actual movement direction, angle, angular velocity and other factors of the electronic rotor measured by the multiple magnetic sensors 204B can be set according to the actual position relationship of the first magnetic sensors.

[0069] like Figure 4 Shown is a cross-sectional schematic diagram of a dual-encoder joint actuator.

[0070] from Figure 4 As can be seen in the figure, the output end 201A of the reducer is connected to the transmission rod 208, the transmission rod 208 is inserted into the hollow shaft 202, and the transmission rod 208 is connected to the second permanent magnet 205A, so as to transmit the rotation of the output end 201A of the reducer to the second permanent magnet 205A. The second permanent magnet rotates under the drive of the transmission rod 208, and the rotation direction, real-time angle, angular velocity and other information of the rotation can be detected by the second magnetic sensor 205B.

[0071] like Figure 4 The figure shows the positional relationship between the assembled first encoder 204 and the second encoder 205. It can be seen that the second encoder 205 includes a second permanent magnet 205A and a second magnetic sensor 205B arranged along the axis Z of the hollow shaft 202, and generally occupies a middle position close to the axis Z. The first encoder 204 includes a first permanent magnet ring 204A and a first magnetic sensor 204B outside thereof, and generally occupies an outer position away from the axis Z. In general, the first encoder and the second encoder can be arranged without axial misalignment, thereby shortening the axial length of the joint actuator.

[0072] like Figure 3 and Figure 4As shown, the shapes of the housing 207 and the controller 206 match each other, and the joint actuator has a mounting seat that matches the above shape. When the housing 207 is installed on the joint actuator, all components of the first encoder 204 and the second encoder 205 can be accommodated therein, so that they are protected by the housing.

[0073] Embodiment 3

[0074] like Figure 5 The figure shows a three-dimensional structural diagram of a dual-encoder joint actuator in which a magnetic sensor and a controller are integrated.

[0075] The dual encoder joint actuator 200 includes a reducer 201, a hollow shaft 202, a motor, a first encoder 204, a second encoder 205, a controller 206, a housing 207, and a transmission rod 208. The reducer 201 includes a reducer output end 201A and a reducer body 201B.

[0076] The first encoder 204 includes a first permanent magnet 204A, a first magnetic sensor 204B, and a first permanent magnet connector 204C. The first permanent magnet 204A is a magnetic ring. The first permanent magnet 204A is connected to the first permanent magnet connector 204C and is installed together with the second permanent magnet 205A. The first encoder 204 measures the first rotation direction, real-time angle, angular velocity, etc. of the motor rotor.

[0077] The number of the first magnetic sensors 204B is four. The first magnetic sensors 204B are directly fixed on the controller 206, and the first magnetic sensors 204B are arranged at the annular position corresponding to the magnetic ring 204A. Optionally, the first magnetic sensors 204B can be arranged along the annular shape at equal distances; optionally, the first magnetic sensors 204B can be arranged along the annular shape in other distribution modes. Figure 5 As shown, the four first magnetic sensors 204B are evenly distributed on the circular track. This arrangement allows the controller 206 to directly install the first magnetic sensor 204B and the second magnetic sensor 205B, so that multiple components are installed together, reducing the number of components that need to be assembled during assembly (the first magnetic sensor circuit board in the aforementioned embodiment is no longer required), and speeding up the assembly efficiency. At the same time, the positional relationship between the magnetic sensor and the controller can be pre-set on the controller, reducing the risk of position errors during on-site assembly.

[0078] like Figure 6 The figure shows a cross-sectional diagram of a dual encoder joint actuator with a magnetic sensor and a controller integrated into one. Figure 6 As can be seen in the figure, the first magnetic sensor 204B is directly fixed on the controller 206, which reduces the number of components that need to be assembled during assembly (the first magnetic sensor circuit board in the above embodiment is no longer required).

[0079] Embodiment 4

[0080] like Figure 7 As shown, the dual-encoder joint actuator 300 includes a reducer 301 , a hollow shaft 302 , a motor 303 , a first encoder 304 , a second encoder 305 , and a controller 306 .

[0081] like Figure 7 As shown, the first encoder 304 is hollow, such as a magnetic ring and a plurality of magnetic sensors arranged in an annular shape. The second encoder 305 is also hollow, such as a magnetic ring or a plurality of magnetic sensors arranged in an annular shape. The outer diameter of the second encoder 305 is smaller than the inner diameter of the first encoder 304. Therefore, the second encoder 305 can be arranged in the inner space of the first encoder 304 in the axial direction without misalignment, thereby shortening the axial length of the joint actuator in the axial direction.

[0082] like Fig. 9 As shown, the first permanent magnet 304A is a magnetic ring. The first magnetic sensor 304B can be a Hall sensor or a magnetic encoder, and the number of the first permanent magnet 304A and the second permanent magnet 305A in the middle of the first permanent magnet 304A is a magnetic ring, and the second magnetic sensor 305B arranged opposite to the second permanent magnet 305A can be a Hall sensor or a magnetic encoder, and the number of the first permanent magnet 304A and ...

[0083] Preferably, both the first permanent magnet and the second permanent magnet are magnetic rings arranged around the central axis Z of the hollow rotating shaft 302 .

[0084] The above setting makes the dual encoder layout more flexible and improves the flexibility and adaptability of product design.

[0085] Preferably, in Figure 7 On the basis of the first encoder and the second encoder, a third encoder is further added. Since the first encoder and the second encoder are both hollow, the third encoder can be placed at the center position of the two (that is, the position of the axis Z of the hollow shaft 302), and the third permanent magnet of the third encoder can be a cylindrical or other shaped permanent magnet, and the third magnetic sensor of the third encoder is also located on the axis Z and arranged opposite to the third permanent magnet.

[0086] like Fig.10As shown, the first permanent magnet 404A is a magnetic ring. The first magnetic sensor 404B can be a Hall sensor or a magnetic encoder, and the number of which can be determined according to the above-mentioned embodiment. The second permanent magnet 405A in the middle of the first permanent magnet 404A is a magnetic ring, and the second magnetic sensor 405B arranged opposite to the second permanent magnet 405A can be a Hall sensor or a magnetic encoder, and the number of which can be determined according to the above-mentioned embodiment. The number of the third permanent magnet 406A is one, for example, a cylindrical permanent magnet. The third magnetic sensor 406B is a magnetic encoder, which is arranged opposite to the third permanent magnet 406A.

[0087] The above dual-encoder or triple-encoder method can be further extended to quad-encoder, quintuple-encoder and other schemes.

[0088] The joint actuator still has two objects to be measured: the motor side and the output side. The measurement elements are three: rotation direction, real-time angle and angular velocity. Therefore, it is necessary to measure: the rotation direction, real-time angle and angular velocity of the motor side, and the rotation direction, real-time angle and angular velocity of the output side.

[0089] When the number of encoders is greater than or equal to three, at least three encoders measure two objects to be measured, and at least two encoders measure the same object, thereby improving the robustness of the measurement by increasing redundancy.

[0090] The objects measured by the encoders and the elements measured can be arbitrarily combined. For example, in the case of three encoders, it is assumed that the first encoder and the second encoder are mainly responsible for measuring the rotation direction and real-time angle on the motor side, and the third encoder mainly measures the rotation direction and real-time angle on the output side, and each encoder can measure the angular velocity. It can also be assumed that the first encoder is mainly responsible for measuring the rotation direction and real-time angle on the motor side, and the second encoder and the third encoder mainly measure the rotation direction and real-time angle on the output side, and each encoder can measure the angular velocity. It can also be that the first encoder and the second encoder are responsible for measuring the rotation direction, real-time angle and angular velocity on the motor side, and the third encoder measures the rotation direction, real-time angle and angular velocity on the output side. Since at least two encoders measure the same element of the same object, the robustness of the system is increased. For example, when a certain encoder has a short-term real-time angle measurement deviation due to electrical interference, the remaining encoders can provide accurate information, thereby improving the robustness of the measurement by increasing redundancy.

[0091] The above solution enables the joint actuator to use more encoders to more accurately measure the various rotation directions, real-time angles, angular velocities and other information of the joint actuator.

[0092] Embodiment 5

[0093] This embodiment defines the transmission mechanism connecting the second permanent magnet 205A and the output end 201A of the reducer.

[0094] like Figure 4 As shown, the transmission rod 208 is directly connected to the reducer output end 201A and the second permanent magnet 205A. The advantage of this direct connection is that it is relatively strong.

[0095] Optionally, the transmission mechanism also includes a first connecting member; the first connecting member is respectively connected to the transmission rod 208 and the reducer output end 201A; the advantage of this method is that the reducer output end 201A and the transmission rod 208 can be manufactured separately and connected through the first connecting member, thereby reducing the manufacturing difficulty and facilitating replacement and maintenance.

[0096] Optionally, the transmission mechanism also includes a second connecting member; the second connecting member connects the transmission rod 208 and the second permanent magnet 205A; the advantage of this approach is that when manufacturing the transmission rod 208, there is no need to consider too much about adapting to the shape of the second permanent magnet 205A, and it is connected through the second connecting member, thereby enhancing the flexibility of adapting to second permanent magnets 205A of different shapes and facilitating replacement and maintenance.

[0097] Optionally, the transmission mechanism includes a first connecting member, a transmission rod, and a second connecting member; the transmission rod connects the first connecting member and the second connecting member respectively; the first connecting member is connected to the reducer output end 201A, and the first connecting member rotates as the reducer output end 201A rotates; the second connecting member is connected to the second permanent magnet, and the second permanent magnet rotates as the second connecting member rotates.

[0098] The first connecting member is a coupling made of a solid material such as metal, which is firmly connected to the output end 201A of the reducer. The transmission rod is a high-strength metal rod, one end of which is connected to the first connecting member and the other end is connected to the second connecting member. The second connecting member is a disc structure with a slot, which is tightly connected to the second permanent magnet 205A.

[0099] The arrangement of this transmission mechanism makes the structure of the entire joint actuator more compact. Since the transmission mechanism is inserted into the hollow shaft (202), space is saved, so that the joint actuator can achieve more functions or reduce the overall volume in a limited space. At the same time, this structure can reduce the interference of external factors on the transmission mechanism and improve the stability and accuracy of the transmission. When the robot performs complex movements, such as performing precision assembly operations in a small space, the movement of the joint can be controlled more accurately, thereby improving the working accuracy and reliability of the robot.

[0100] According to an embodiment of the present disclosure, the present disclosure also provides a robot including: the dual encoder joint actuator as described above.

[0101] It should be noted that, although several parts, structures or units are mentioned in the above detailed description, this division is not mandatory. In fact, according to the embodiments of the present application, the features and functions of two or more parts, structures or units described above can be embodied in one module or unit. On the contrary, the features and functions of one part, structure or unit described above can be further divided into multiple modules or units to be embodied.

[0102] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the contents disclosed herein. The present application is intended to cover any variations, uses or adaptations of the present application, which follow the general principles of the present application and include common knowledge or customary technical means in the art that are not disclosed in the present application.

[0103] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A dual encoder joint actuator (200), comprising a motor (203), a reducer (201), a hollow shaft (202), and a controller (206); the motor (203) comprises a motor rotor and a motor stator; the reducer (201) comprises a reducer output end (201A); characterized in that: The joint actuator (200) comprises: A first encoder (204) comprises a first permanent magnet (204A) fixed to the motor rotor, and at least one first magnetic sensor (204B); the first magnetic sensor (204B) is arranged opposite to the first permanent magnet (204A); The second encoder (205) comprises a second permanent magnet (205A) located in the middle of the first permanent magnet (204A), and a second magnetic sensor (205B); the second permanent magnet (205A) rotates with the output end (201A) of the reducer through a transmission mechanism; the second magnetic sensor (205B) and the second permanent magnet (205A) are arranged relative to each other.

2. The joint actuator according to claim 1, characterized in that: The first permanent magnet (204A) is a magnetic ring arranged around the central axis of the hollow rotating shaft (202); the first permanent magnet (204A) is fixedly connected to the motor rotor through a first permanent magnet connector (204C), and the first permanent magnet (204A) rotates synchronously with the rotation of the motor rotor.

3. The joint actuator according to claim 1, characterized in that: The first magnetic sensor (204B) is a Hall sensor, and the number of the Hall sensors is at least two.

4. The joint actuator according to claim 1, characterized in that: The first magnetic sensor (204B) is a magnetic encoder.

5. The joint actuator according to claim 1, characterized in that: When the number of the at least one first magnetic sensor (204B) is plural, the plurality of first magnetic sensors (204B) are arranged around the hollow rotating shaft (202).

6. The joint actuator according to claim 1, characterized in that: The second permanent magnet (205A) is a permanent magnet located on the central axis of the hollow rotating shaft (202); and the second magnetic sensor (205B) is located on the central axis of the hollow rotating shaft (202).

7. The joint actuator according to claim 1, characterized in that: The second permanent magnet (305A) is a magnetic ring arranged around the central axis of the hollow rotating shaft (202); and the second magnetic sensor (305B) is arranged around the hollow rotating shaft (202).

8. The joint actuator according to claim 1, characterized in that: The transmission mechanism is inserted into the hollow rotating shaft (202).

9. The joint actuator according to claim 1, characterized in that: The transmission mechanism comprises a transmission rod (208); the transmission rod (208) is connected to the reducer output end (201A), and the transmission rod (208) rotates as the reducer output end (201A) rotates; the transmission rod (208) is connected to the second permanent magnet (205A), and the second permanent magnet (205A) rotates as the transmission rod (208) rotates.

10. The joint actuator according to claim 8, characterized in that: The transmission rod rotates around the central axis of the hollow rotating shaft (202).

11. The joint actuator according to claim 1, characterized in that: The transmission mechanism further comprises a first connecting member; the first connecting member is respectively connected to the transmission rod (208) and the output end (201A) of the reducer; The transmission mechanism also includes a second connecting member; the second connecting member connects the transmission rod (208) and the second permanent magnet (205A).

12. The joint actuator according to claim 1, characterized in that: In the second encoder (205), the number of the second permanent magnet (205A) is one, the number of the second magnetic sensor (205B) is one, and the second magnetic sensor (205B) is installed on the controller (206).

13. The joint actuator according to claim 1, characterized in that: In the second encoder (305), the second permanent magnet is a magnetic ring arranged around the central axis of the hollow rotating shaft (202); The second magnetic sensor is a Hall sensor, and the number of the second magnetic sensors is at least two; or the second magnetic sensor is a magnetic sensor, and the number of the second magnetic sensor is at least one.

14. The joint actuator according to claim 13, characterized in that: The joint actuator further includes: a third encoder; The third encoder includes: a third permanent magnet located in the middle of the second permanent magnet, and a third magnetic sensor installed on the controller (206).

15. A robot, characterized in that: include: A joint actuator as described in any one of claims 1 to 14.

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