Linear electric drive joint of humanoid robot

Abstract

The invention relates to the technical field of mechanical joints, in particular to a humanoid robot linear electric drive joint which comprises a shell, a front end cover and a rear end cover, the front end cover and the rear end cover are fixed to the two ends of the shell respectively, and an execution assembly and a drive control assembly are arranged in the shell; the execution assembly comprises a reverse planetary roller screw and a motor, and the drive control assembly comprises an encoder composed of a coded disc and a magnetic ring, a pull pressure sensor and a driver. Aiming at the technical problem that an existing linear joint has defects, a reverse planetary roller lead screw is adopted as a main transmission component, and the lead screw, a roller and a nut of the reverse planetary roller lead screw are in linear contact, so that high precision, long service life, high integration level and high thrust density can be achieved while high bearing and high speed are achieved; therefore, the method is suitable for use scenes of humanoid robot joints.

Description

Technical Field

[0001] The present invention relates to the technical field of mechanical joints, and in particular to a linear electric drive joint of a humanoid robot. Background Art

[0002] The existing robot joints are mainly divided into rotary and linear types, among which linear joints are mainly divided into ball screw joints and hydraulic joints. The structure of the ball screw used in the ball screw joint determines that the balls need to continuously circulate and roll in the raceway, resulting in a low speed that the screw can reach. In addition, the point contact characteristics of the balls and the raceway make the ball screw relatively low in load and poor in impact resistance. Under high load and large impact conditions, the raceway and balls are easily damaged. The linear joints used in humanoid robots are generally hydraulic joints, which have high load and good impact resistance, but there are still problems such as complex hydraulic oil pipe layout, heavy weight of hydraulic oil pump, and high processing cost of related parts. Summary of the invention

[0003] In response to the technical problems of defects in existing linear joints, the present invention provides a linear electric-driven joint for a humanoid robot, whose main transmission component adopts a reverse planetary roller screw, which has the characteristic of line contact between the screw, roller and nut, so that it can achieve high load-bearing capacity and high speed while achieving high precision, high life, high integration and high thrust density, thus being suitable for the use scenarios of humanoid robot joints.

[0004] The technical solution provided by the present invention is: a linear electric drive joint of a humanoid robot, comprising a shell, a front end cover and a rear end cover, wherein the front end cover and the rear end cover are respectively fixed to the two ends of the shell, and an execution assembly and a drive control assembly are arranged in the shell; the execution assembly comprises a reverse planetary roller screw and a motor, and the motor is located on the outside of the reverse roller screw; the reverse planetary roller screw comprises a screw, a roller and a nut, the screw passes through the front end cover, a plurality of rollers are arranged around the outside of the screw, the nut is arranged on the outside of the screw, the screw is meshed with the rollers, and the rollers are meshed with the nut; the motor comprises a stator and a rotor, the stator is arranged on the outside of the rotor and is fixedly connected to the shell, and the nut is connected to the nut. The rotor is fixedly connected; the drive control component is located on the side of the reverse planetary roller screw close to the rear end cover, and the drive control component includes an encoder composed of a code disk and a magnetic ring, a tension and pressure sensor and a driver; the tension and pressure sensor is integrated on the rear end cover; the encoder and the tension and pressure sensor are both electrically connected to the driver; the end of the nut is fixedly sleeved with a sleeve, the magnetic ring is fixed on the sleeve, a bearing seat is provided on the shell, a deep groove ball bearing is provided between the sleeve and the bearing seat, the inner ring of the deep groove ball bearing is fixed to the sleeve, the outer ring of the deep groove ball bearing is abutted against the bearing seat, and the code disk is fixed on the bearing seat; a joint is fixedly provided on the rear end cover and the end of the screw, and a spherical bearing is provided on the joint.

[0005] Optionally, the sleeve is a cup-shaped structure, the cup-shaped structure is sleeved on the end of the lead screw, and the bottom of the cup-shaped structure abuts against the end of the lead screw.

[0006] Optionally, at least one through hole is formed at the bottom of the cup-shaped structure.

[0007] Optionally, the code disk and the magnetic ring are both hollow ring structures, the magnetic ring is sleeved and fixed on the shaft sleeve, and the code disk surrounds the outer side of the magnetic ring.

[0008] Optionally, the lead screw passes through the front end cover, an anti-rotation copper sleeve is arranged between the front end cover and the lead screw, the anti-rotation copper sleeve is fixedly connected to the front end cover, a flat hole is arranged on the anti-rotation copper sleeve, an inner wall flat position is arranged on the flat hole, an outer wall flat position is arranged on the lead screw, and the inner wall flat position abuts against the outer wall flat position.

[0009] Optionally, a solid lubricant is embedded in the anti-rotation copper sleeve.

[0010] Optionally, a heat dissipation shell is fixedly arranged between the shell and the rear end cover, the heat dissipation shell is a cup-shaped structure, the opening of the cup-shaped structure is fixedly connected to the shell, and the driver is located in the heat dissipation shell; the driver includes at least one layer of substrate stacked from the rear end cover to the front end cover, the substrate close to the rear end cover is an aluminum substrate, the aluminum substrate is bonded to the bottom surface of the cup-shaped structure, and thermal conductive silicone grease is filled between the aluminum substrate and the bottom surface of the cup-shaped structure.

[0011] Optionally, the tension and pressure sensor is a spoke-type tension and pressure sensor.

[0012] Optionally, an adjusting nut is provided at the rear end cover and / or the end of the screw; when an adjusting nut is provided at the rear end cover, the adjusting nut is threadedly matched with the joint, and the joint is connected to the rear end cover after passing through the adjusting nut; when an adjusting nut is provided at the end of the screw, the adjusting nut is threadedly matched with the joint, and the joint is connected to the end of the screw after passing through the adjusting nut.

[0013] Optionally, a boss is provided on the joint.

[0014] Optionally, the shell, the front end cover, the rear end cover and the heat dissipation shell are all made of aluminum-lithium alloy material.

[0015] Beneficial Effects

[0016] The technical solution provided by the present invention has the following beneficial effects compared with the prior art: in order to solve the technical problems of defects in existing linear joints, the main transmission component of the present invention adopts a reverse planetary roller screw, which has the characteristic of line contact between the screw, roller and nut, so that high load-bearing capacity and high speed can be achieved while achieving high precision, high life, high integration and high thrust density, thus being suitable for use in humanoid robot joints. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic structural diagram of a linear electrically driven joint of a humanoid robot proposed in an embodiment of the present invention.

[0018] Figure 2 This is a schematic structural diagram of the front end cover of the linear electric drive joint of a humanoid robot proposed in an embodiment of the present invention. DETAILED DESCRIPTION

[0019] In order to further understand the content of the present invention, the present invention is described in detail in conjunction with the accompanying drawings and embodiments.

[0020] The present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are only used to explain the relevant inventions, rather than to limit the invention. It should also be noted that, for the convenience of description, only the parts related to the invention are shown in the accompanying drawings. The words "first", "second", etc. described in the present invention are set for the convenience of describing the technical solution of the present invention, and have no specific limiting effect. They are all general references and do not constitute a limiting effect on the technical solution of the present invention. It should be noted that, in the absence of conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. In the description of the present invention, it should be noted that the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention 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 of the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. Unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be a connection between the insides of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. Multiple technical solutions in the same embodiment, and multiple technical solutions in different embodiments, can be arranged and combined to form new technical solutions without contradictions or conflicts, all of which are within the scope of protection required by the present invention.

[0021] Example 1

[0022] Combined with Figure 1-2 This embodiment proposes a linear electric drive joint of a humanoid robot, including a shell 107, a front cover 103 and a rear cover 203, the front cover 103 and the rear cover 203 are respectively fixed to the two ends of the shell 107, and an actuator component and a drive control component are arranged in the shell 107.

[0023] The actuator assembly includes a reverse planetary roller screw and a motor, and the motor is located outside the reverse planetary roller screw.

[0024] In the actuator assembly, the reverse planetary roller screw includes a screw 1091, a roller 1093 and a nut 1092. The screw 1091 passes through the front end cover 103, and a plurality of rollers 1093 are arranged around the outside of the screw 1091. The nut 1092 is arranged on the outside of the screw 1091. The screw 1091 and the roller 1093 are meshed, and the roller 1093 and the nut 1092 are meshed.

[0025] In the actuator assembly, the motor includes a stator 1081 and a rotor 1082 . The stator 1081 is disposed outside the rotor 1082 and fixedly connected to the housing 107 . The nut 1092 is fixedly connected to the rotor 1082 .

[0026] The drive control assembly is located on the side of the reverse planetary roller screw near the rear end cover 203, and the drive control assembly includes an encoder composed of a code disc 2011 and a magnetic ring 2012, a tension and pressure sensor, and a driver 202. In the drive control assembly, the tension and pressure sensor is integrated on the rear end cover 203. The encoder and the tension and pressure sensor are both electrically connected to the driver 202.

[0027] The end of the nut 1092 is fixedly sleeved with a sleeve 111, the magnetic ring 2012 is fixed on the sleeve 111, a bearing seat 112 is arranged on the housing 107, a deep groove ball bearing 110 is arranged between the sleeve 111 and the bearing seat 112, the inner ring of the deep groove ball bearing 110 is fixed to the sleeve 111, the outer ring of the deep groove ball bearing 110 is in contact with the bearing seat 112, and the code disk 2011 is fixed on the bearing seat 112.

[0028] Furthermore, a joint 102 is fixedly provided on the rear end cover 203 and the end of the lead screw 1091 , and a spherical bearing 101 is provided on the joint 102 .

[0029] Based on the structural form of the humanoid robot linear electric drive joint recorded above, its main working principle is: the lead screw 1091, the roller 1093 and the nut 1092 constitute a reverse planetary roller lead screw, the nut 1092 is processed with threads, the roller 1093 is processed with threads and gears, and the lead screw 1091 is processed with threads and gears. The nut 1092 and the roller 1093 are meshed through threads, and the roller 1093 and the lead screw 1091 are meshed through threads and gears. The stator 1081 of the motor can drive the rotor 1082 of the motor to drive the nut 1092 to rotate, and then drive the lead screw 1091 to move linearly. The movement of the lead screw is controlled by the motor, and the motor is controlled by the drive control component. The encoder in the drive control component can output the number of rotations of the nut 1092 to the driver 202, and the tension and pressure sensor can output the tension and pressure of the joint to the driver 202. The driver 202 can drive the movement of the joint in combination with the input information of the encoder and the tension and pressure sensor. As the lead screw 1091 is extended and retracted, the end of the lead screw 1091 can be driven to achieve linear motion through the joint bearing 101 provided through the joint 102, and the distance between the end of the lead screw 1091 and the joint bearing 101 provided through the joint 102 on the rear end cover 203 can be changed.

[0030] In this embodiment, the motor is preferably a permanent magnet frameless motor. The tension and pressure sensor in the drive control assembly preferably adopts a spoke-type tension and pressure sensor, and the tension and pressure sensor is integrated on the rear end cover 203. The integrated tension and pressure sensor reduces the overall space occupied, and compared with the box membrane tension and pressure sensor, the spoke-type tension and pressure sensor has higher accuracy and stability.

[0031] Furthermore, in order to improve the smoothness and stability of the rotation of the nut 1092 , this embodiment further provides a deep groove ball bearing 110 through the combination of the shaft sleeve 111 and the bearing seat 112 . The deep groove ball bearing 110 is arranged on the outer side of the nut 1092 near the rear end cover 203 .

[0032] Accordingly, in one embodiment, an angular contact bearing 106 may be provided between the nut 1092 and the housing 107 at the outer side of the nut 1092 near the front end cover 103, so as to further ensure the smoothness of the rotation of the nut 1092 under load. A four-point angular contact bearing 106 may be preferably used here. The angular contact bearing 106 may be assembled through the locking nut 105, which is threadedly matched with the outer shell of the nut 1092, and one side of the angular contact bearing 106 abuts against the end of the locking nut 105, and the other side may abut against the shoulder on the housing 107 or the shoulder on the outer side of the nut 1092, so as to achieve assembly.

[0033] The drive control assembly in this embodiment includes an encoder composed of a code disk 2011 and a magnetic ring 2012. The encoder is assembled in such a manner that the magnetic ring 2012 is fixed to the shaft sleeve 111, the inner ring of the deep groove ball bearing 110 is fixed to the shaft sleeve 111, the outer ring of the deep groove ball bearing 110 is in contact with the bearing seat 112, and the code disk 2011 is fixed to the bearing seat 112. Based on this assembly method, when the linear electric drive joint of the humanoid robot works normally, the number of rotations of the magnetic ring 2012 is consistent with the nut 1092, and the code disk 2011 can read the number of rotations of the magnetic ring 2012.

[0034] The encoder adopts a non-contact design, and it is necessary to ensure that the magnetic ring 2012 and the code disk 2011 have a high coaxiality, otherwise the rotation accuracy will be affected. Based on the setting method of the encoder in this embodiment, the coaxiality of the magnetic ring 2012 and the code disk 2011 of the encoder can be guaranteed to the greatest extent. The main principle is: the coaxiality between the magnetic ring 2012 and the code disk 2011 is guaranteed by the high precision of the deep groove ball bearing 110 itself. It can be understood that the inner ring of the deep groove ball bearing 110 is matched with the sleeve 111, the magnetic ring 2012 is also matched with the sleeve 111, the outer ring of the deep groove ball bearing 110 is matched with the bearing seat 112, and the code disk 2011 is also matched with the bearing seat 112. This design only needs to ensure the coaxiality between the bearing mating surface on the sleeve 111 and the magnetic ring 2012 mating surface, and the coaxiality between the bearing mating surface on the bearing seat 112 and the code disk 2011 mating surface, so as to ensure the coaxiality between the magnetic ring 2012 and the code disk 2011. That is, the design of this embodiment uses the deep groove ball bearing 110 as a reference datum for the dimension chain, thereby shortening the dimension chain between the magnetic ring 2012 and the code disk 2011 to the greatest extent.

[0035] In a preferred embodiment, the code disc 2011 and the magnetic ring 2012 are both hollow annular structures, the magnetic ring 2012 is sleeved and fixed on the shaft sleeve 111, and the code disc 2011 surrounds the outer side of the magnetic ring 2012. In this embodiment, the hollow annular structure of the code disc 2011 and the magnetic ring 2012 allows the encoder to be sleeved on the nut 1092 of the reverse planetary roller screw as a whole, so that the encoder does not occupy the space in the length direction of the electric drive joint.

[0036] Furthermore, an obvious advantage of this embodiment is that the sleeve 111 and the nut 1092 are matched and fixed, making the assembly and disassembly of the deep groove ball bearing 110 and the magnetic ring 2012 more convenient, and a more convenient assembly method also helps to improve the accuracy.

[0037] In a preferred embodiment, the sleeve 111 is a cup-shaped structure, which is sleeved on the end of the lead screw 1091, and the bottom of the cup-shaped structure abuts against the end of the lead screw 1091. The sleeve 111 with a cup-shaped structure can prevent the grease inside the planetary roller 1093 and the lead screw 1091 from being thrown out during movement, so that the planetary roller 1093 and the lead screw 1091 maintain a good lubrication state, and prevent the thrown grease from causing adverse effects on the encoder and the driver 202.

[0038] The above-mentioned cup-shaped sleeve 111 still has certain defects under certain circumstances, that is, the setting of the cup sleeve may make the space at the rear end of the nut 1092 closed. When the linear electric drive joint of the humanoid robot works normally, if the space at the rear end of the nut 1092 is completely closed or closed to a certain extent, then when the lead screw 1091 is extended, the lead screw 1091 together with the roller 1093 will form a piston-like structure, resulting in negative pressure at the rear end of the lead screw 1091; and when the lead screw 1091 is retracted, high pressure will be generated at the rear end of the lead screw 1091. This change in air pressure formed by the linear motion of the lead screw 1091 will cause a certain retardation to the movement of the lead screw 1091 and will affect the actual load of the lead screw 1091. The impact on the lead screw 1091 will eventually lead to a reduction in the overall response speed and force control bandwidth of the joint.

[0039] To solve the above defects, in an optimized embodiment, at least one through hole 1110 is opened at the bottom of the cup-shaped sleeve 111. Thus, the through hole 1110 at the bottom of the sleeve 111 can eliminate the airtightness inside the reverse planetary roller screw, preventing the airtightness from affecting the response speed of the reverse planetary roller screw.

[0040] In other embodiments, the lead screw 1091 passes through the front end cover 103, an anti-rotation copper sleeve 104 is provided between the front end cover 103 and the lead screw 1091, the anti-rotation copper sleeve 104 is fixedly connected to the front end cover 103, a flat hole is provided on the anti-rotation copper sleeve 104, an inner wall flat position is provided on the flat hole, an outer wall flat position is provided on the lead screw 1091, and the inner wall flat position abuts against the outer wall flat position. Therefore, in this case, the hollow flat hole of the anti-rotation copper sleeve 104 has one side, two sides or more inner wall flat positions, which cooperate with the outer wall flat positions at the end of the lead screw 1091 to prevent the lead screw 1091 from rotating under the influence of transmission friction.

[0041] During the normal use of the linear electric drive joint of the humanoid robot, there will inevitably be impacts, and due to the transmission characteristics of the lead screw 1091 and the nut 1092, part of the impact force is the axial force acting on the lead screw 1091 and the nut 1092, and the other part is converted into the torque acting on the lead screw 1091. The setting of the anti-rotation copper sleeve 104 can further enable the linear electric drive joint of the humanoid robot to withstand greater impacts, because: the flat position on the anti-rotation copper sleeve 104 matches the flat position of the lead screw 1091, and the torque on the lead screw 1091 can be further transmitted to the anti-rotation copper sleeve 104, and the connection part on the joint surface of the anti-rotation copper sleeve 104 and the front end cover 103 finally bears this part of the torque, thereby improving the impact resistance and load-bearing capacity of the lead screw 1091, and ensuring the stability of the lead screw 1091 during linear motion.

[0042] The anti-rotation copper sleeve 104 cooperates with the lead screw 1091, which can not only ensure the stability of the lead screw 1091 during linear motion, but also reduce the friction during motion. The principle of reducing friction is that the main body of the anti-rotation copper sleeve 104 is made of copper, which has a certain self-lubricating effect. In the actual use of the anti-rotation copper sleeve 104, an anti-rotation copper sleeve 104 with a solid lubricant can be selected. For example, a preferred anti-rotation copper sleeve 104 has a solid lubricant such as graphite embedded in its main structure, thereby achieving a self-lubricating effect, thereby reducing the friction during motion.

[0043] In an optional implementation manner, a plurality of circular holes can be provided on the joint surface between the anti-rotation copper sleeve 104 and the front end cover 103, and cylindrical pins can be inserted into the circular holes. By cooperating with the cylindrical pins and the circular holes, the fixed connection between the anti-rotation copper sleeve 104 and the front end cover 103 can be ensured, thereby preventing the anti-rotation copper sleeve 104 and the front end cover 103 from loosening and rotating.

[0044] Generally speaking, the driver 202 is roughly divided into a main control board, a driving board, and a capacitor board, and the electrical components installed thereon will inevitably generate heat when working. Based on this, in a preferred embodiment, a heat dissipation shell 113 is fixedly arranged between the shell 107 and the rear end cover 203, and the heat dissipation shell 113 is a cup-shaped structure, and the opening of the cup-shaped structure is fixedly connected to the shell 107, and the driver 202 is located in the heat dissipation shell 113; the driver 202 includes at least one layer of substrate 2021 stacked from the rear end cover 203 to the front end cover 103, and the substrate 2021 close to the rear end cover 203 is an aluminum substrate, and the aluminum substrate is attached to the bottom surface of the cup-shaped structure, and the aluminum substrate and the bottom surface of the cup-shaped structure are filled with thermal conductive silicone grease.

[0045] In this embodiment, the high-heat-generating element can be set on the bottom-layer substrate 2021, which is the substrate 2021 close to the rear end cover 203. Since the bottom-layer substrate 2021 is an aluminum substrate, the bottom surface of the bottom-layer substrate 2021 is bonded to the bottom surface of the heat dissipation shell 113, and high-thermal conductivity silicone grease is filled between the bonding surfaces. The heat generated by the high-heat-generating element can be transferred to the heat dissipation shell 113 to the greatest extent, and the heat is dissipated through the larger surface area of ​​the heat dissipation shell 113, thereby further ensuring the normal operation of the driver 202.

[0046] The linear electric drive joint of the humanoid robot in this embodiment has a joint 102 fixedly arranged on the rear end cover 203 and the end of the lead screw 1091, and a joint bearing 101 is arranged on the joint 102 to meet the use scenario of the robot joint. The relative rotation angle between the joint 102 and the lead screw 1091 in the axial direction is defined as the orientation of the joint 102, or the orientation of the joint 102 can be understood as the axial rotation of the joint 102 itself. Obviously, different orientations of the joint 102 will result in different orientations of the joint bearing 101.

[0047] In order to finally adjust the orientation of the spherical bearing 101, the rotation of the joint 102 can be adjusted. In a preferred embodiment, an adjusting nut 114 is provided at the rear end cover 203 and / or at the end of the lead screw 1091. When the adjusting nut 114 is provided at the rear end cover 203, the adjusting nut 114 is threadedly matched with the joint 102, and the joint 102 is threadedly connected with the rear end cover 203 after passing through the adjusting nut 114; when the end of the lead screw 1091 is provided with an adjusting nut 114, the adjusting nut 114 is threadedly matched with the joint 102, and the joint 102 is threadedly connected with the end of the lead screw 1091 after passing through the adjusting nut 114.

[0048] Therefore, based on the setting of the adjusting nut 114, the connector 102 and the adjusting nut 114 can form an independent threaded matching area. After the connector 102 is inserted into the rear end cover 203 or the lead screw 1091, it can be freely rotated to adjust the angle of the connector 102. When the angle of the connector 102 is adjusted, first temporarily fix the connector 102 by hand or tooling, and then through the threaded matching of the connector 102 and the adjusting nut 114, continuously rotate the adjusting nut 114 until the end face of the adjusting nut 114 abuts against the rear end cover 203 or the end of the lead screw 1091, so that the connector 102 can be locked and fixed.

[0049] In a practical application, the design of the adjustment nut 114 is used to level the joints 102 at both ends. The adjustment nut 114 is only provided at the rear end cover 203 and is only used to adjust the orientation of the joint 102 at the rear end cover 203 to ensure that the orientation of the joint 102 at the rear end cover 203 is consistent with the orientation of the joint 102 at the end of the lead screw 1091. This ensures that the joints 102 at the front and rear ends are parallel. The joint bearings 101 installed on the joints 102 can allow the connectors at both ends of the linear electric drive joint of the humanoid robot to have a certain angle of rotation space, so that the overall structure has a higher degree of freedom.

[0050] In other preferred embodiments, a boss is provided on the connector 102, and the boss is used to abut against the front cover 103, or the rear cover 203 or the adjusting nut 114. When the boss is used to abut against the front cover 103, the size of the boss needs to be designed to be larger than the diameter of the lead screw 1091. When the lead screw 1091 retracts to the stroke limit, the bottom surface of the boss on the connector 102 can contact the upper surface of the front cover 103 to form a hard limit, so that when the lead screw 1091 exceeds the limit due to control system problems or other external factors, it is ensured that the lead screw 1091 will not retract into the interior and cause damage to the components. When the boss is used to abut against the rear cover 203 or the adjusting nut 114, the screw-in depth of the connector 102 can be limited, which can help the assembly of the connector 102, and the abutment of the boss with the adjusting nut 114 or the rear cover 203 also expands the friction contact area, which helps prevent the connector 102 from loosening.

[0051] In a preferred embodiment, the housing 107, the front cover 103, the rear cover 203 and the heat dissipation housing 113 can all be made of ultra-high strength aluminum-lithium alloy material with a density of 2.67 g / cm 3 , the tensile strength can reach 695Mpa, and the yield strength can reach 566Mpa. Compared with the highest strength 7075 aluminum alloy among traditional aluminum alloys, its density is reduced by 5%, the tensile strength is increased by 30%, and the yield strength is increased by 20%. Using ultra-high-strength aluminum-lithium alloy to replace traditional aluminum alloys can reduce the structural weight by more than 15% and significantly improve the thrust density.

[0052] To sum up, this embodiment proposes a linear electric drive joint of a humanoid robot, whose main transmission component adopts a reverse planetary roller screw, and the characteristic of line contact between the screw 1091, the roller 1093, and the nut 1092 can achieve high load-bearing capacity and high speed while achieving high precision, high life, high integration and high thrust density, which is of great significance in the field of humanoid robots, which have high requirements on the weight and performance of joints.

[0053] The present invention and its embodiments are described schematically above, and the description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. Therefore, if a person skilled in the art is inspired by it and designs a structural method and an embodiment similar to the technical solution without creativity without departing from the purpose of the invention, they shall all fall within the protection scope of the present invention.

Claims

1. A linear electric drive joint of a humanoid robot, characterized in that: The invention comprises a housing (107), a front end cover (103) and a rear end cover (203), wherein the front end cover (103) and the rear end cover (203) are respectively fixed to two ends of the housing (107), and an actuator component and a drive control component are arranged in the housing (107); The actuator assembly includes a reverse planetary roller screw and a motor, wherein the motor is located outside the reverse planetary roller screw; The reverse planetary roller screw comprises a screw (1091), a roller (1093) and a nut (1092); the screw (1091) passes through the front end cover (103); a plurality of rollers (1093) are arranged around the outside of the screw (1091); the nut (1092) is arranged on the outside of the screw (1091); the screw (1091) and the rollers (1093) are meshed with each other; and the rollers (1093) and the nut (1092) are meshed with each other. The motor comprises a stator (1081) and a rotor (1082), the stator (1081) is arranged outside the rotor (1082) and fixedly connected to the housing (107), and the nut (1092) is fixedly connected to the rotor (1082); The drive control component is located on a side of the reverse planetary roller screw close to the rear end cover (203), and the drive control component comprises an encoder composed of a code disk (2011) and a magnetic ring (2012), a tension and pressure sensor, and a driver (202); the tension and pressure sensor is integrated on the rear end cover (203); the encoder and the tension and pressure sensor are both electrically connected to the driver (202); the end of the nut (1092) is fixedly sleeved with a shaft sleeve (111), The magnetic ring (2012) is fixed on the shaft sleeve (111), a bearing seat (112) is arranged on the housing (107), a deep groove ball bearing (110) is arranged between the shaft sleeve (111) and the bearing seat (112), the inner ring of the deep groove ball bearing (110) is fixed to the shaft sleeve (111), the outer ring of the deep groove ball bearing (110) is in contact with the bearing seat (112), and the code disk (2011) is fixed on the bearing seat (112); A joint (102) is fixedly provided on the rear end cover (203) and the end of the lead screw (1091), and a spherical bearing (101) is provided on the joint (102).

2. A humanoid robot linear electric drive joint according to claim 1, characterized in that: The shaft sleeve (111) is a cup-shaped structure, the cup-shaped structure is sleeved on the end of the lead screw (1091), and the bottom of the cup-shaped structure abuts against the end of the lead screw (1091).

3. A humanoid robot linear electric drive joint according to claim 2, characterized in that: At least one through hole (1110) is formed at the bottom of the cup-shaped structure.

4. The linear electric drive joint of a humanoid robot according to claim 1, characterized in that: The code disc (2011) and the magnetic ring (2012) are both hollow ring structures; the magnetic ring (2012) is sleeved and fixed on the shaft sleeve (111); and the code disc (2011) surrounds the outer side of the magnetic ring (2012).

5. The linear electric drive joint of a humanoid robot according to claim 1, characterized in that: The lead screw (1091) passes through the front end cover (103), and an anti-rotation copper sleeve (104) is arranged between the front end cover (103) and the lead screw (1091). The anti-rotation copper sleeve (104) is fixedly connected to the front end cover (103), and a flat hole is arranged on the anti-rotation copper sleeve (104), and an inner wall flat position is arranged on the flat hole. An outer wall flat position is arranged on the lead screw (1091), and the inner wall flat position abuts against the outer wall flat position.

6. The linear electric drive joint of a humanoid robot according to claim 5, characterized in that: Solid lubricant is embedded in the anti-rotation copper sleeve (104).

7. The humanoid robot linear electric drive joint according to claim 1, characterized in that: A heat dissipation shell (113) is fixedly arranged between the shell (107) and the rear end cover (203); the heat dissipation shell (113) is a cup-shaped structure; an opening of the cup-shaped structure is fixedly connected to the shell (107); the driver (202) is located in the heat dissipation shell (113); the driver (202) includes at least one layer of substrate (2021) stacked from the rear end cover (203) to the front end cover (103); the substrate (2021) close to the rear end cover (203) is an aluminum substrate; the aluminum substrate is bonded to the bottom surface of the cup-shaped structure, and thermal conductive silicone grease is filled between the aluminum substrate and the bottom surface of the cup-shaped structure.

8. The linear electric drive joint of a humanoid robot according to claim 1, characterized in that: The tension and pressure sensor is a spoke-type tension and pressure sensor.

9. The humanoid robot linear electric drive joint according to claim 1, characterized in that: An adjusting nut (114) is provided at the rear end cover (203) and / or at the end of the lead screw (1091); When the rear end cover (203) is provided with an adjusting nut (114), the adjusting nut (114) is threadedly matched with the joint (102), and the joint (102) passes through the adjusting nut (114) and is connected to the rear end cover (203); When an adjusting nut (114) is provided at the end of the lead screw (1091), the adjusting nut (114) is threadedly matched with the joint (102), and the joint (102) passes through the adjusting nut (114) and is connected to the end of the lead screw (1091).

10. A linear electric drive joint of a humanoid robot according to claim 1 or 9, characterized in that: The joint (102) is provided with a boss.

11. The humanoid robot linear electric drive joint according to claim 7, characterized in that: The housing (107), the front end cover (103), the rear end cover (203) and the heat dissipation housing (113) are all made of aluminum-lithium alloy material.

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