Humanoid robot linear joint and humanoid robot

Abstract

According to the humanoid robot linear joint and the humanoid robot, an output end knuckle bearing seat and a fixed end knuckle bearing seat are integrally integrated on a push rod and a force sensor correspondingly, the integration degree is high, the structure is compact, and therefore the axial size of the linear joint can be effectively shortened. A motor assembly is arranged in a joint shell, an encoder assembly is connected with the motor assembly, the motor assembly is connected with a ball screw pair, the ball screw pair is connected with a push rod assembly, a front end cover is arranged on one side of the joint shell, a rear end cover is arranged on the other side of the joint shell, and the push rod assembly is arranged in the front end cover. An output end joint bearing seat is integrally integrated on the push rod assembly, the output end joint bearing seat is arranged outside the front end cover, the force sensor is arranged on one side of the rear end cover, a fixed end joint bearing seat is integrally integrated on the force sensor, and the fixed end joint bearing seat is arranged outside the force sensor.

Description

Technical Field

[0001] This application relates to the field of intelligent machinery technology, and particularly to a linear joint of a humanoid robot and a humanoid robot. Background Art

[0002] With the increasingly wide application of humanoid robots, the joint actuators of humanoid robots, as the core components for realizing motion control, are particularly suitable for parts such as the arms and legs of humanoid robots that require high explosive force movements due to their high efficiency and impact resistance characteristics.

[0003] Currently, the mainstream electric drive linear joints on the market usually adopt a lead screw pair and a push rod to form a telescopic mechanism, use an electric motor as the power source, and are equipped with a force sensor and rod end bearings at both ends of the joint. The fixed end of the existing linear joint is equipped with a force sensor, and each end of the joint is equipped with a rod end bearing for connecting the body structural parts. However, the integration degree of the above linear joints is not high enough, and the overall structure is not compact enough. In particular, the usage in places with high axial dimension requirements, such as the lower arm of the upper limb of a humanoid robot, does not meet the requirements. Moreover, during the use process, due to the low integration degree, the arm length of the humanoid robot is forced to be lengthened or the joint is exposed, affecting the aesthetics and practicality. Summary of the Invention

[0004] This application provides a linear joint of a humanoid robot and a humanoid robot to solve the above technical problems.

[0005] In the first aspect of this application, a linear joint of a humanoid robot is provided, including: a joint housing, a motor assembly, an encoder assembly, a front end cover, a rear end cover, a ball screw pair, a push rod assembly, a force sensor, a fixed end joint bearing seat, and an output end joint bearing seat; The motor assembly is arranged in the joint housing, the encoder assembly is connected to the motor assembly, the motor assembly is connected to the ball screw pair, the ball screw pair is connected to the push rod assembly, the front end cover is arranged on one side of the joint housing, the rear end cover is arranged on the other side of the joint housing, the push rod assembly is arranged in the front end cover, the output end joint bearing seat is integrally formed on the push rod assembly, the output end joint bearing seat is arranged outside the front end cover, the force sensor is arranged on one side of the rear end cover, the fixed end joint bearing seat is integrally formed on the force sensor, and the fixed end joint bearing seat is arranged outside the force sensor; The motor assembly is used to drive the ball screw pair to rotate, the ball screw pair is used to drive the push rod assembly to perform telescopic movement, and the fixed end joint bearing seat and the output end bearing seat are used to connect with joint bearings.

[0006] Optionally, the motor assembly includes a motor stator, rolling elements, and motor magnets. The motor stator is fixedly connected to the inside of the joint housing. The rolling elements are arranged inside the motor stator. The motor magnets are arranged between the rolling elements and the motor stator. The motor magnets are arranged outside the rolling elements. An internal cavity is arranged in the rolling elements and is used for placing the ball screw pair.

[0007] Optionally, the ball screw pair includes a screw rod, a limit piece, and a screw nut. The screw rod is arranged in the internal cavity. One end of the screw rod is provided with a circular positioning boss. The screw rod is connected to the push rod assembly through the circular positioning boss. The other end of the screw rod is connected to the limit piece. The limit piece is arranged in the internal cavity. The screw nut is mounted on the screw rod. The screw nut is fixed in the joint housing. The push rod, the limit piece, and the screw nut in the push rod assembly cooperate to limit the forward and backward movement of the screw rod.

[0008] Optionally, the push rod assembly includes a push rod, a push rod bearing seat, a push rod guide groove, and a limit sleeve. One end of the push rod is connected to the circular positioning boss on the screw rod. The other end of the push rod is connected to the push rod bearing seat. The push rod bearing seat extends out of the front end cover and is integrally formed with the output end joint bearing seat. The push rod is provided with the push rod guide groove. The limit sleeve is arranged between the push rod and the front end cover. The inner surface of the limit sleeve is set as a square surface corresponding to the outer surface contour of the push rod. The limit sleeve is provided with a limit sleeve flat position, and the limit sleeve flat position corresponds to the positioning boss of the front end cover to realize the positioning of the front end cover and the limit sleeve.

[0009] Optionally, one end of the rolling element is connected to the inner ring of the first bearing through a thin nut. The other end of the rolling element is connected to the inner ring of the second bearing. The outer ring of the first bearing is concentrically fixed to the joint housing. The outer ring of the second bearing is concentrically fixed to the joint housing with the rear end cover. A wave spring is installed between the outer ring of the second bearing and the rear end cover.

[0010] Optionally, the rear end cover is concentrically connected and fixed to the joint housing. A cavity is arranged in the rear end cover. A joint encoder static disk is installed in the cavity. The strain gauge on the force sensor is connected to the cavity on the rear end cover.

[0011] Optionally, a first pin hole, a second pin hole, and a third pin hole are provided on the circular positioning boss. The second pin hole is disposed between the first pin hole and the third pin hole. The first pin hole and the second pin hole are through openings, and the third pin hole is a blind hole.

[0012] Optionally, first engraved lines indicating the assembly orientation are engraved on the outer surfaces of the joint housing, the rear end cover, and the force sensor.

[0013] Optionally, second engraved lines indicating the assembly orientation are engraved on the outer surfaces of the front end cover and the joint housing, and the second engraved lines correspond to the first engraved lines.

[0014] A second aspect of the present application provides a humanoid robot, including a humanoid robot body and the humanoid robot linear joint as described in the first aspect and any one of the first aspects. The humanoid robot linear joints are installed on the arms and legs of the humanoid robot body.

[0015] As can be seen from the above technical solutions, the present application has the following advantages: 1. By integrally integrating the output end joint bearing seat and the fixed end joint bearing seat on the push rod and the force sensor respectively, the linear joint of the present application has a high integration degree and a compact structure, thereby effectively shortening the axial dimension of the linear joint, which is beneficial to the miniaturization design and anthropomorphic design of the humanoid robot.

[0016] 2. The push rod and the force sensor respectively integrate the joint bearing seats at the output end and the fixed end. The joint bearings can be directly press-fitted onto the structures of the push rod and the force sensor without using additional fasteners, effectively compressing the axial space of the joint, thereby reducing the number of components of the linear joint and simplifying the assembly difficulty of the joint bearings, which is beneficial to the mass production of the linear joint. Description of the Drawings

[0017] In order to more clearly illustrate the technical solutions in the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0018] Figure 1 is an overall mechanism schematic diagram of the humanoid robot linear joint provided by the present application; Figure 2 is a side view schematic diagram of the structure of the humanoid robot linear joint provided by the present application; Figure 3 is Figure 2 a structural cross-sectional view taken along A-A in Figure 4It is another side view schematic diagram of the structure of the linear joint of the humanoid robot provided by this application; Figure 5 It is a schematic diagram of the push rod assembly installed in the linear joint of the humanoid robot provided by this application; Figure 6 It is a schematic diagram of the extended state of the linear joint of the humanoid robot provided by this application. Specific embodiments

[0019] In this application, the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal", etc. is based on the orientation or positional relationship shown in the drawings, and is only used to illustrate the relative positional relationship between each component or part, and does not particularly limit the specific installation orientation of each component or part.

[0020] Moreover, in addition to being able to represent the orientation or positional relationship, some of the above terms may also be used to represent other meanings. For example, the term "upper" may also be used to represent a certain attachment relationship or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to the specific situation.

[0021] In addition, the terms "install", "set", "be provided with", "connect", "be connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or there is an internal connection between two devices, components or parts. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to the specific situation.

[0022] In addition, the structures, ratios, sizes, etc. drawn in the drawings of this application are only used to cooperate with the content disclosed in the specification for those skilled in the art to understand and read, and are not used to limit the implementation conditions of this application. Therefore, they do not have technical essential significance. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects that this application can produce and the purposes that can be achieved, should still fall within the scope covered by the technical content disclosed in this application.

[0023] Next, the technical solutions in this application will be clearly and completely described in conjunction with the drawings in this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope protected by this application.

[0024] The fixed end of the existing linear joint is equipped with a force sensor, and a rod end bearing is arranged at each end of the joint for connecting the body structural members. However, the integration degree of the above linear joint is not high enough, and the overall structure is not compact enough. Especially in places where the axial dimension requirements are relatively high, such as the forearm of the upper limb of a humanoid robot, the usage situation cannot meet the requirements. Moreover, during the use process, due to the low integration degree, the arm length of the humanoid robot is forced to be elongated or the joints are exposed, affecting the aesthetics and practicality.

[0025] Based on this, the present application provides a linear joint for a humanoid robot and a humanoid robot. The linear joint of the present application integrally integrates an output end joint bearing seat and a fixed end joint bearing seat on the push rod and the force sensor respectively, with high integration degree and compact structure, thereby effectively shortening the axial dimension of the linear joint, which is beneficial to the miniaturization design and anthropomorphic design of the humanoid robot.

[0026] Please refer to Figures 1 to 6 , the first aspect of the present application provides a linear joint for a humanoid robot, including: a joint housing 1, a motor assembly, an encoder assembly, a front end cover 9, a rear end cover 10, a ball screw pair, a push rod assembly, a force sensor 12, a fixed end joint bearing seat 15, and an output end joint bearing seat 21; The motor assembly is arranged in the joint housing 1, the encoder assembly is connected to the motor assembly, the motor assembly is connected to the ball screw pair, the ball screw pair is connected to the push rod assembly, the front end cover 9 is arranged on one side of the joint housing 1, the rear end cover 10 is arranged on the other side of the joint housing 1, the push rod assembly is arranged in the front end cover 9, the output end joint bearing seat 21 is integrally integrated on the push rod assembly, the output end joint bearing seat 21 is arranged outside the front end cover 9, the force sensor 12 is arranged on one side of the rear end cover 10, the fixed end joint bearing seat 15 is integrally integrated on the force sensor 12, and the fixed end joint bearing seat 15 is arranged outside the force sensor 12; the motor assembly is used to drive the ball screw pair to rotate, the ball screw pair is used to drive the push rod assembly to perform telescopic movement, and the fixed end joint bearing seat 15 and the output end bearing seat are used to connect with joint bearings.

[0027] First, the functions and roles of each component in the present application are described: Joint housing 1: As the external support structure of the entire linear joint, it provides installation space and protection for each internal component, and can integrate components such as the motor assembly, encoder assembly, ball screw pair, push rod assembly, and force sensor 12 to ensure the relative positions and coordinated work of each component.

[0028] Motor assembly: It provides the power source for the movement of the linear joint, and the motor assembly is used to drive the ball screw pair to rotate.

[0029] Encoder assembly: It detects the rotational position and speed information of the motor assembly. The encoder assembly is connected to the motor assembly to monitor the motion state of the motor assembly in real time and feedback the detected signals to the control system, so that the control system can precisely control the motion of the motor to achieve precise positioning and speed adjustment of the linear joint.

[0030] Front end cover 9: It is installed on one side of the joint housing 1, which plays a certain role in enclosing and protecting the internal structure of the joint housing 1. At the same time, it provides guidance for the installation and movement of the push rod assembly. Among them, the front end cover 9 cooperates with the push rod assembly to guide the push rod assembly to perform telescopic movement. And there are engraved lines indicating the assembly orientation on the outer surface of the front end cover 9, which correspond to the engraved lines on the outer surfaces of the joint housing 1, the rear end cover 10, and the force sensor 12, and are used to position the parts during assembly, so as to control the position of the output end joint bearing.

[0031] Rear end cover 10: It is installed on the other side of the joint housing 1, jointly encloses the internal space of the joint with the front end cover 9, and at the same time provides support for the installation of the force sensor 12. The rear end cover 10 is connected to the force sensor 12 to fix the force sensor 12 on the joint housing 1. And there are also engraved lines indicating the assembly orientation on the outer surface of the rear end cover 10, which participate in the assembly positioning.

[0032] Ball screw pair: It converts the rotational motion of the motor assembly into the linear telescopic motion of the push rod assembly. The ball screw pair is used as a transmission mechanism between the motor assembly and the push rod assembly, and realizes efficient transmission through the cooperation of the screw rod 16 and the screw nut 19. In this application, both ends of the screw rod 16 are respectively connected to the push rod 18 and the limit piece 17. The end face of the push rod 18 and the limit piece 17 respectively limit the backward and forward movement of the screw rod with the two end planes of the screw nut 19, forming a mechanical limit to ensure that the telescopic range of the push rod assembly is within a safe range.

[0033] Push rod assembly: It realizes the telescopic motion of the linear joint and integrates the output end joint bearing seat 21. The push rod assembly performs telescopic movement driven by the ball screw pair, converting the rotational motion of the motor assembly into a linear motion. Among them, the front end of the push rod 18 is a circular positioning boss 161, and there are three pin holes on the boss, two of which are through holes and one is a blind hole. It is connected to the screw rod 16 through a pin to realize the assembly of the two. The output end joint bearing seat 21 is integrally formed on the push rod 18 and is used to connect with the joint bearing to transmit the motion of the linear joint to other components.

[0034] Force sensor 12: It is used to detect the magnitude of the force borne by the linear joint. The force sensor 12 is arranged on one side of the rear end cover 10, and its interior includes a cavity for accommodating the static disk 14 of the joint encoder. This force sensor 12 is a strain gauge type tensile and compressive force sensor, and the strain gauges are evenly attached to the top of its cavity or the inner surface of the cavity circumference, converting the magnitude of the force into an electrical signal for output. Moreover, a force sensor bearing seat 124 and a fixed-end joint bearing seat 15 are integrally formed on the force sensor 12 for connecting with the joint bearing.

[0035] Fixed-end joint bearing seat 15: As a connecting component between the force sensor 12 and the joint bearing, it is fixed at one end of the linear joint. This fixed-end joint bearing seat 15 is arranged outside the force sensor 12 for connecting with the joint bearing.

[0036] Output-end joint bearing seat 21: As a connecting component between the push rod assembly and the joint bearing, it outputs the motion of the linear joint. The output-end joint bearing seat 21 is arranged outside the front end cover 9 and is connected with the joint bearing, transmitting the telescopic motion of the push rod assembly to other components through the joint bearing to achieve the motion output of the linear joint.

[0037] In practical applications, after the motor assembly is powered on, the electromagnetic conversion principle inside the motor causes the motor rotor to rotate, thereby driving the lead screw 16 in the ball screw pair connected thereto to rotate. When the lead screw 16 rotates, since the lead screw nut 19 is fixed, the lead screw 16 is forced to move axially. Among them, the lead screw nut 19 is fixed inside the joint housing 1, and the push rod assembly performs telescopic movement under the axial movement of the lead screw 16. The output-end joint bearing seat 21 on the push rod assembly is connected with the joint bearing, transmitting the telescopic motion of the push rod assembly to other components to achieve the motion output of the linear joint.

[0038] Among them, the force sensor 12 is arranged on one side of the rear end cover 10. When the linear joint bears an external force, the strain gauges on the force sensor 12 deform, converting the magnitude of the force into an electrical signal for output, realizing the detection of the force borne by the linear joint.

[0039] Among them, the encoder assembly is used to detect information such as the rotation position and speed of the motor assembly in real time and feedback the signal to the control system. The control system precisely controls the motion of the motor according to the feedback signal to achieve precise positioning and speed adjustment of the linear joint.

[0040] During the assembly process, it should be noted that by aligning the engraved lines indicating the assembly orientation on the outer surfaces of the front end cover 9, rear end cover 10, joint housing 1, and force sensor 12 to position the parts, the relative positions of the output-end joint bearing seat 21 and the fixed-end joint bearing seat 15 are controlled, ensuring the assembly accuracy and motion performance of the linear joint.

[0041] Therefore, in the present application, by integrating the push rod 18 and the force sensor 12 with the joint bearing seats of the output end and the fixed end respectively, the integration degree is high and the structure is compact. The joint bearing can be directly press-fitted onto the structures of the push rod 18 and the force sensor 12, so that without using additional fasteners, the axial space of the joint can be effectively compressed, aiming to reduce the number of components of the linear joint and simplify the assembly difficulty of the joint bearing.

[0042] Optionally, the motor assembly includes a motor stator 2, rolling elements 3, and a motor magnet 4; The motor stator 2 is fixedly connected to the inside of the joint housing 1. The rolling elements 3 are arranged inside the motor stator 2. A motor magnet 4 is arranged between the rolling elements 3 and the motor stator 2. The motor magnet 4 is arranged outside the rolling elements 3. An internal cavity is arranged in the rolling elements 3, and the internal cavity is used to place the ball screw pair.

[0043] In the embodiment of the present application, the motor stator 2 is the fixed part of the motor assembly, providing a magnetic field basis and structural support for the operation of the motor. The motor stator 2 is fixedly connected to the inside of the joint housing 1 to ensure the stable installation of the motor in the linear joint. When the motor is powered on and running, the motor stator 2 generates a magnetic field, interacts with the motor magnet 4, and drives the rolling elements 3 to rotate. The stable structure of the motor stator 2 can also ensure that the motor will not displace or deform during high-speed operation and under certain external forces, ensuring the normal operation of the motor.

[0044] Among them, the rolling elements 3 are the rotating part of the motor assembly. Under the action of the magnetic field generated by the motor magnet 4, electrical energy is converted into mechanical energy and rotation is achieved. The rolling elements 3 are arranged inside the motor stator 2 and rotate relative to the motor stator 2 through the magnetic field action of the motor magnet 4. An internal cavity is arranged in the rolling elements 3, and this internal cavity provides an installation space for the ball screw pair, enabling the ball screw pair to be closely integrated with the motor assembly and achieving efficient power transmission. The rotation of the rolling elements 3 drives the screw rod 16 of the ball screw pair to rotate, thereby converting the rotational motion of the motor into the linear motion of the ball screw pair.

[0045] By arranging an internal cavity in the rolling elements 3, it can be ensured that the ball screw pair can be smoothly installed and operate stably in the internal cavity. At the same time, a certain gap is maintained between the outer surface of the rolling elements 3 and the inner surface of the motor stator 2. The specific value of this gap is not specifically limited in the present application and can be set according to the actual situation, so as to ensure that the rolling elements 3 can rotate flexibly under the action of the magnetic field and reduce friction and energy loss.

[0046] The motor magnet 4 interacts with the motor stator 2 to drive the rolling element 3 to rotate. The motor magnet 4 is arranged outside the rolling element 3 and is located between the motor stator 2 and the rolling element 3. When the motor is powered on, the motor stator 2 generates a magnetic field. Under the action of the magnetic field, the motor magnet 4 generates a magnetic force, which interacts with the magnetic field of the motor stator 2 to form an electromagnetic torque, driving the rolling element 3 to rotate. It should be noted that the motor magnet 4 is usually installed outside the rolling element 3 by bonding to ensure that it will not fall off or displace during the operation of the motor.

[0047] The internal cavity in the rolling element 3 is used to place the ball screw pair, which is for realizing the integrated design of the motor assembly and the ball screw pair. The internal cavity provides a space for the installation and operation of the ball screw pair, enabling the ball screw pair to be tightly connected to the motor assembly and realizing the efficient transmission of power. By placing the ball screw pair in the internal cavity, the overall volume of the linear joint is reduced, the structural compactness is improved, and at the same time, it is beneficial to reduce the weight of the linear joint and improve the motion performance of the humanoid robot.

[0048] As the power source of the linear joint of the humanoid robot, through the coordinated work of components such as the motor stator 2, the rolling element 3, the motor magnet 4 and the internal cavity, the motor assembly realizes the conversion of electrical energy into mechanical energy and drives the ball screw pair to drive the push rod assembly to perform linear telescopic motion. At the same time, the integrated setting of the motor assembly and the ball screw pair improves the structural compactness and motion stability of the linear joint, providing a strong guarantee for the efficient and precise motion of the humanoid robot.

[0049] Optionally, the ball screw pair includes a lead screw 16, a limit piece 17 and a lead screw nut 19; the lead screw 16 is arranged in the internal cavity. One end of the lead screw 16 is set as a circular positioning boss 161. The lead screw 16 is connected to the push rod assembly through the circular positioning boss 161. The other end of the lead screw 16 is connected to the limit piece 17. The limit piece 17 is arranged in the internal cavity. The lead screw nut 19 is installed on the lead screw 16, and the lead screw nut 19 is fixed in the joint housing 1. The push rod 18 in the push rod assembly, the limit piece 17 and the lead screw nut 19 cooperate to limit the forward and backward movement of the lead screw 16.

[0050] In the embodiment of the present application, the lead screw 16 is a transmission component of the ball screw pair. One end of the lead screw 16 is set as a circular positioning boss 161, and the other end is connected to the limit piece 17. The setting of the limit piece 17 plays a role in restricting the movement of the lead screw 16 to prevent the lead screw 16 from having excessive displacement during the movement process.

[0051] The lead screw 16 rotates driven by the motor assembly. Since the lead nut 19 is fixed, the lead screw 16 is forced to move axially. The push rod 18 is connected to the lead screw 16, so that synchronous movement can be achieved. However, due to the restraint of the limit sleeve 20, it cannot rotate and finally only exhibits linear motion, thus realizing the form conversion from the rotational motion of the motor to the linear motion and ensuring that the lead screw 16 can perform linear motion along its axis. Among them, the limit piece 17 is arranged in the inner cavity of the motor assembly and connected to one end of the lead screw 16 to ensure that it can play a limiting role when the lead screw 16 moves to the limited position.

[0052] The lead nut 19 has a thread structure matching the lead screw 16, so that the lead screw 16 can move on the lead nut 19.

[0053] In practical applications, when the lead screw 16 rotates driven by the motor assembly, the threads inside the lead nut 19 mesh with the threads of the lead screw 16, causing the lead screw 16 to perform linear motion along the axis, thus realizing the transmission from the rotational motion of the motor to the linear motion and providing power for the telescopic motion of the linear joint of the humanoid robot.

[0054] Furthermore, the lead nut 19 is connected and fixed to the joint housing 1, so that the lead screw 16 is forced to move axially when rotating. The push rod 18 moves synchronously with the lead screw 16 through key connection, and at the same time, the rotation is restricted by the limit sleeve 20. Finally, the rotational input of the motor can be converted into the linear output of the push rod 18. The lead nut 19 plays both a bearing role and a guiding role in this process.

[0055] Among them, it should be noted that the push rod 18 in the push rod assembly is connected to the circular positioning boss 161 at one end of the lead screw 16. When the push rod assembly moves backward under the action of external force or internal driving force, it will drive the lead screw 16 to move backward together. During the backward movement of the lead screw 16, the limit piece 17 will contact the rear end face of the inner cavity of the motor assembly to form a mechanical block. Since the strength and stiffness of the limit piece 17 are large enough to withstand the force generated by the backward movement of the lead screw 16, the lead screw 16 is prevented from continuing to move backward, realizing the limit of the backward movement of the lead screw 16.

[0056] Optionally, the push rod assembly includes a push rod 18, a push rod bearing seat 181, a push rod guide groove 182 and a limit sleeve 20; One end of the push rod 18 is connected to the circular positioning boss 161 on the lead screw 16, and the other end of the push rod 18 is connected to the push rod bearing seat 181. The push rod bearing seat 181 extends out of the front end cover 9 and is integrally formed and connected to the output end spherical plain bearing seat 21. A push rod guide groove 182 is provided on the push rod 18. A limit sleeve 20 is provided between the push rod 18 and the front end cover 9. The inner surface of the limit sleeve 20 is set as a square surface corresponding to the outer surface contour of the push rod 18. A flat position 201 of the limit sleeve is provided on the limit sleeve 20, and the flat position 201 of the limit sleeve corresponds to the front end cover positioning boss 91 to realize the positioning of the front end cover 9 and the limit sleeve 20.

[0057] In the embodiment of the present application, one end of the push rod 18 is connected to the circular positioning boss 161 on the lead screw 16. The connection method can be key connection and adhesive connection. The other end of the push rod 18 is connected to the push rod bearing seat 181 to ensure the smoothness and flexibility of the push rod 18 during movement.

[0058] As a connecting component between the lead screw 16 and the push rod bearing seat 181, the push rod 18 transmits the power of the lead screw 16 to the push rod bearing seat 181, and then drives the output end spherical plain bearing seat 21 to move, realizing the telescopic function of the linear joint. The push rod bearing seat 181 and the output end spherical plain bearing seat 21 are integrally formed and connected. This integrally formed setting improves the strength and stiffness of the connecting part between the push rod bearing seat 181 and the output end spherical plain bearing seat 21, reduces the stress concentration and deformation of the connecting part, and thus is beneficial to improving the overall performance of the linear joint. The integrally formed connection can be realized by casting, forging or machining, etc., and is not specifically limited here.

[0059] The integrally formed connection reduces the number of parts and connecting parts, reduces the assembly difficulty and failure rate of the linear joint, and helps to improve the overall stability and reliability of the structure.

[0060] Among them, the push rod guide groove 182 is provided on the push rod 18. The push rod guide groove 182 usually cooperates with the pin on the circular positioning boss 161 to form a sliding guide structure. The pin on the boss is inserted into the guide groove to guide and limit the movement of the push rod 18, ensuring that the push rod 18 can move along a predetermined linear trajectory.

[0061] Among them, the inner surface of the limit sleeve 20 is set as a square surface corresponding to the outer surface contour of the push rod 18. The square surface can effectively limit the rotation of the push rod 18, so that the push rod 18 can only perform linear motion, and the size of the square surface matches the outer surface of the push rod 18 to ensure the close fit between the limit sleeve 20 and the push rod 18 and prevent the push rod 18 from rotating during movement.

[0062] The limiting sleeve 20 is provided with a limiting sleeve flat position 201, and the limiting sleeve flat position 201 corresponds to the positioning boss 91 on the front end cover. The positioning boss is a protruding structure on the front end cover 9 and cooperates with the limiting sleeve flat position 201 of the limiting sleeve 20 to achieve the positioning of the front end cover 9 and the limiting sleeve 20, thereby ensuring the position accuracy between the limiting sleeve 20 and the front end cover 9 during the installation process and improving the assembly quality of the linear joint.

[0063] The square inner surface of the limiting sleeve 20 and the setting of the limiting sleeve flat position 201 prevent the push rod 18 from rotating during movement and can only move in a straight line direction, thus ensuring the movement accuracy and stability of the linear joint.

[0064] In practical applications, when the motor assembly drives the lead screw 16 to rotate, under the action of the lead screw nut 19 and the push rod 18, the lead screw 16 will be forced to move linearly. Since the push rod 18 is connected to the circular positioning boss 161 on the lead screw 16, the force on the lead screw 16 will be applied to the push rod 18, and the movement of the push rod 18 is further transmitted to the push rod bearing seat 181. The push rod bearing seat 181 drives the output end joint bearing seat 21 to move through integral molding connection, thereby realizing the power output of the linear joint.

[0065] Optionally, one end of the rolling element 3 is connected to the inner ring of the first bearing 5 through a thin nut, and the other end of the rolling element 3 is connected to the inner ring of the second bearing 6. The outer ring of the first bearing 5 is concentrically fixed with the joint housing 1, and the outer ring of the second bearing 6 is concentrically fixed with the rear end cover 10 to the joint housing 1. A wave spring 11 is installed between the outer ring of the second bearing 6 and the rear end cover 10.

[0066] In the embodiment of the present application, one end of the rolling element 3 is connected to the inner ring of the first bearing 5 through a thin nut. The thin nut has a small thickness and a light weight and is suitable for occasions with limited space. During installation, the thin nut is threadedly engaged with the thread at the end of the rolling element 3, and after being tightened, the rolling element 3 is tightly connected to the inner ring of the first bearing 5, thereby effectively transmitting torque and axial force.

[0067] Due to the tightening force of the thin nut, sufficient pre-tightening force is generated between the rolling element 3 and the inner ring of the first bearing 5 to ensure that there is no relative movement between the two. At the same time, the thin nut can also play a certain anti-loosening role to prevent loosening of the connection due to vibration or other reasons during the movement of the linear joint.

[0068] The other end of the rolling element 3 is directly connected to the inner ring of the second bearing 6, usually by interference fit or key connection. The interference fit utilizes the interference amount between the end of the rolling element 3 and the inner ring of the second bearing 6 to tightly combine the two together to achieve the transmission of torque and axial force.

[0069] Among them, the outer ring of the first bearing 5 is concentrically fixed with the joint housing 1. The outer ring of the first bearing 5 is installed in the joint housing 1, and the concentric fixation of the outer ring of the first bearing 5 and the joint housing 1 ensures the stability and precision of the rolling elements 3 during movement.

[0070] The outer ring of the second bearing 6 is concentrically fixed with the rear end cover 10 to the joint housing 1. The rear end cover 10 serves as the closed end of the linear joint. A wave spring 11 is installed between the rear end cover 10 and the outer ring of the second bearing 6. The wave spring 11 provides a pre-tightening force to compensate for the axial clearance and ensure the tight fit between the bearing outer ring and the rear end cover 10.

[0071] Through the synergistic action of the thin nut, the bearing inner ring, the outer ring fixation, and the wave spring 11, the rolling element 3 assembly achieves precise fit and stable connection between the rolling elements 3 and the joint housing 1 and the rear end cover 10. And the thin nut ensures the reliable connection between the rolling element 3 and the bearing inner ring. The fixing method of the bearing outer ring ensures the stable movement of the rolling element 3 between the joint housing 1 and the rear end cover 10. The wave spring 11 provides the necessary pre-tightening force to compensate for the axial clearance generated by movement. Through the cooperation of each component, the movement precision, load-bearing capacity, and service life of the linear joint are effectively improved, providing a reliable guarantee for the movement of the humanoid robot.

[0072] Optionally, the rear end cover 10 is concentrically connected and fixed to the joint housing 1. A cavity is provided in the rear end cover 10, and a joint encoder static disk 14 is installed in the cavity. The strain gauge on the force sensor 12 is connected to the cavity on the rear end cover 10.

[0073] In the embodiment of the present application, the rear end cover 10 and the joint housing 1 are concentrically connected and fixed. The concentric connection method ensures the position precision of the two in the axial and radial directions, enabling the linear joint to maintain a stable axis during movement and reducing vibration and wear caused by eccentricity.

[0074] Among them, a cavity is provided in the rear end cover 10, which is used to position and install the joint encoder static disk 14 to ensure the relative position between the joint encoder static disk 14 and the rear end cover 10 remains stable. Specifically, the joint encoder static disk 14 is installed in the cavity of the rear end cover 10, usually fixed by screw connection. The screw connection method has the advantages of reliable connection and convenient disassembly, and is suitable for occasions that require frequent maintenance and replacement of the encoder.

[0075] The joint encoder static disk 14 cooperates with the moving disk of the joint encoder to detect the movement position and speed information of the linear joint. By installing the joint encoder static disk 14 in the cavity of the rear end cover 10, the encoder can accurately obtain the movement parameters of the linear joint and feedback these parameters to the control system to achieve precise control of the linear joint.

[0076] Among them, the strain gauge on the force sensor 12 is connected to the cavity on the rear end cover 10. The strain gauge on the force sensor 12 is the core component of the force sensor 12 and can convert the force received by the linear joint into an electrical signal. When an external force acts on the linear joint, the strain gauge will undergo a slight deformation, resulting in a change in its resistance value. By measuring the change in the resistance value of the strain gauge, the magnitude and direction of the force received by the linear joint can be calculated.

[0077] Optionally, a first pin hole 25, a second pin hole 23, and a third pin hole 22 are provided on the circular positioning boss 161. The second pin hole 23 is provided between the first pin hole 25 and the third pin hole 22. The first pin hole 25 and the second pin hole 23 are through holes, and the third pin hole 22 is a blind hole.

[0078] In the embodiment of the present application, a first pin hole 25, a second pin hole 23, and a third pin hole 22 are provided on the circular positioning boss 161. Among them, the first pin hole 25 is a through hole, that is, it penetrates from one side surface of the circular positioning boss 161 to the other side surface. The through first pin hole 25 enables the pin to be inserted from one side of the circular boss and protrude from the other side during the assembly process, facilitating positioning connection with other components.

[0079] Similarly, the second pin hole 23 is also provided on the circular positioning boss 161 and is located between the first pin hole 25 and the third pin hole 22. The second pin hole 23 is also a through hole and, similar to the first pin hole 25, has the characteristic of penetrating from one side of the boss to the other side.

[0080] The first pin hole 25 and the second pin hole 23 are used in combination, which can further improve the positioning accuracy between the circular positioning boss 161 and other components. By providing multiple through pin holes, positioning constraints can be achieved, ensuring that the positional relationship between the circular positioning boss 161 and other components is accurate and error-free, and the stability of the connection structure can be improved.

[0081] A third pin hole 22 is also provided on the circular positioning boss 161. The third pin hole 22 is a blind hole, that is, the third pin hole 22 only opens on one side surface of the circular positioning boss 161 and does not penetrate the entire boss internally.

[0082] In practical applications, when the lead screw 16 and the push rod 18 are connected and installed, first, a blind pin is installed in the third pin hole 22. The push rod 18 is provided with a guide groove corresponding to the pin on the third pin hole 22, thus facilitating the guiding and positioning of the push rod 18. Then, pins are used to install in the first pin hole 25 and the second pin hole 23 to complete the assembly of the push rod 18 and the lead screw 16.

[0083] Optionally, first engraved lines 24 indicating the assembly orientation are engraved on the outer surfaces of the joint housing 1, the rear end cover 10, and the force sensor 12.

[0084] In the embodiment of the present application, during the assembly process of the linear joint, first engraved lines 24 indicating the assembly orientation are engraved on the outer surfaces of the joint housing 1, the rear end cover 10, and the force sensor 12, aiming to provide intuitive and accurate assembly guidance for the assemblers, ensuring that each component can be precisely assembled according to the design requirements, thereby improving the assembly accuracy, reliability, and stability of the linear joint.

[0085] Through the mutual cooperation of the first engraved lines 24 on the joint housing 1, the rear end cover 10, and the force sensor 12, a complete assembly indication mark is formed. The assemblers can perform precise assembly according to these engraved lines, reducing assembly errors and improving the overall assembly accuracy of the linear joint.

[0086] Optionally, second engraved lines 26 indicating the assembly orientation are engraved on the outer surfaces of the front end cover 9 and the joint housing 1, and the second engraved lines 26 correspond to the first engraved lines 24.

[0087] In the embodiment of the present application, in the assembly system of the linear joint, first engraved lines 24 have been set on the outer surfaces of the joint housing 1, the rear end cover 10, and the force sensor 12 to indicate the assembly orientation, while the newly added second engraved lines 26 on the outer surfaces of the front end cover 9 and the joint housing 1 correspond to the first engraved lines 24. The second engraved lines 26 and the first engraved lines 24 complement each other functionally and jointly constitute a complete assembly indication for the linear joint. Among them, the first engraved lines 24 mainly indicate the assembly orientation of the joint housing 1, the rear end cover 10, and the force sensor 12, while the second engraved lines 26 focus on the assembly relationship between the front end cover 9 and the joint housing 1. They correspond to each other in position and direction, ensuring the overall coordination of each component of the linear joint during the assembly process.

[0088] The synergistic effect of the first engraved lines 24 and the second engraved lines 26 enables the assemblers to precisely control the assembly orientation of each component from multiple angles. By accurately assembling the components corresponding to the first engraved lines 24 and the second engraved lines 26 respectively, assembly errors are reduced, and the overall assembly accuracy of the linear joint is improved.

[0089] The accurate assembly orientation ensures the movement matching accuracy between the components of the linear joint, reduces friction and resistance during the movement process, and improves the movement speed, acceleration, and positioning accuracy of the linear joint.

[0090] The second aspect of the present application provides a humanoid robot, including a humanoid robot body and the linear joint of the humanoid robot as described in the first aspect and any one of the first aspect. The linear joints of the humanoid robot are installed on the arms and legs of the humanoid robot body.

[0091] It should be noted that the above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but rather should be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A humanoid robot linear joint, characterized in that: include: Joint housing, motor assembly, encoder assembly, front cover, rear cover, ball screw pair, push rod assembly, force sensor, fixed end joint bearing seat and output end joint bearing seat; The motor assembly is arranged in the joint housing, the encoder assembly is connected to the motor assembly, the motor assembly is connected to the ball screw pair, the ball screw pair is connected to the push rod assembly, the front end cover is arranged on one side of the joint housing, the rear end cover is arranged on the other side of the joint housing, the push rod assembly is arranged in the front end cover, the output end joint bearing seat is integrated on the push rod assembly, and the output end joint bearing seat is arranged outside the front end cover, the force sensor is arranged on one side of the rear end cover, the fixed end joint bearing seat is integrated on the force sensor, and the fixed end joint bearing seat is arranged outside the force sensor; The motor assembly is used to drive the ball screw pair to rotate, the ball screw pair is used to drive the push rod assembly to telescopically move, and the fixed end joint bearing seat and the output end bearing seat are used to be connected to the joint bearing.

2. The humanoid robot linear joint according to claim 1, characterized in that: The motor assembly includes a motor stator, a rolling element and a motor magnetic steel; The motor stator is fixedly connected to the inside of the joint housing, the rolling body is arranged inside the motor stator, the motor magnet is arranged between the rolling body and the motor stator, the motor magnet is arranged outside the rolling body, an internal cavity is arranged in the rolling body, and the internal cavity is used to place the ball screw pair.

3. The humanoid robot linear joint according to claim 2, characterized in that: The ball screw pair includes a lead screw, a limit plate and a lead screw nut; The lead screw is arranged in the internal cavity, one end of the lead screw is arranged as a circular positioning boss, the lead screw is connected to the push rod assembly through the circular positioning boss, the other end of the lead screw is connected to the limit plate, the limit plate is arranged in the internal cavity, the lead screw nut is installed on the lead screw, and the lead screw nut is fixed in the joint housing, the push rod in the push rod assembly, the limit plate and the lead screw nut cooperate to limit the forward and backward movement of the lead screw.

4. The humanoid robot linear joint according to claim 3, characterized in that: The push rod assembly comprises a push rod, a push rod bearing seat, a push rod guide groove and a limit sleeve; One end of the push rod is connected to the circular positioning boss on the lead screw, and the other end of the push rod is connected to the push rod bearing seat. The push rod bearing seat extends out of the front end cover and is integrally connected with the output end joint bearing seat. The push rod is provided with the push rod guide groove, and the limit sleeve is provided between the push rod and the front end cover. The inner surface of the limit sleeve is set to a square surface corresponding to the outer surface contour of the push rod, and a limit sleeve flat position is set on the limit sleeve, and the limit sleeve flat position corresponds to the positioning boss of the front end cover to realize the positioning of the front end cover and the limit sleeve.

5. The humanoid robot linear joint according to claim 2, characterized in that: One end of the rolling body is connected to the inner ring of the first bearing through a thin nut, and the other end of the rolling body is connected to the inner ring of the second bearing. The outer ring of the first bearing is concentrically fixed to the joint housing, and the outer ring of the second bearing is concentrically fixed to the joint housing with the rear end cover, and a wave spring is installed between the outer ring of the second bearing and the rear end cover.

6. The humanoid robot linear joint according to claim 5, characterized in that: The rear end cover is concentrically connected and fixed to the joint housing, a cavity is provided in the rear end cover, a joint encoder static disk is installed in the cavity, and the strain gauge on the force sensor is connected to the cavity on the rear end cover.

7. The humanoid robot linear joint according to claim 3, characterized in that: The circular positioning boss is provided with a first pin hole, a second pin hole and a third pin hole, the second pin hole is arranged between the first pin hole and the third pin hole, the first pin hole and the second pin hole are through openings, and the third pin hole is a blind hole.

8. The humanoid robot linear joint according to claim 1, characterized in that: The outer surfaces of the joint housing, the rear end cover and the force sensor are all engraved with first engraved lines indicating the assembly orientation.

9. The humanoid robot linear joint according to claim 8, characterized in that: The outer surfaces of the front end cover and the joint housing are both engraved with second engraved lines indicating the assembly orientation, and the second engraved lines correspond to the first engraved lines.

10. A humanoid robot, characterized in that: It comprises a humanoid robot body and the humanoid robot linear joint as claimed in any one of claims 1 to 9, wherein the arms and legs of the humanoid robot body are equipped with the humanoid robot linear joint.

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