Modular joint quick-change structure, mechanical arm and robot

Abstract

The application relates to a joint connecting structure of a mechanical arm, and provides a modular joint quick-change structure, a mechanical arm and a robot, the quick-change structure is used for connecting an uplink joint and a downlink joint, the downlink joint is provided with a downlink connecting seat, the uplink joint is provided with an uplink connecting seat, a plug-in guiding structure is arranged between the two, and electric, gas and liquid line connections are realized through a plug and a socket; the downlink connecting seat is provided with a mechanical connecting hole, the uplink connecting seat is provided with a mechanical connecting head, a plurality of steel ball holes are arranged in the side wall of the mechanical connecting head in the circumferential direction, locking steel balls are arranged in the steel ball holes, and a locking sliding groove matched with the locking steel balls is arranged on the inner wall of the mechanical connecting hole; an expansion head is arranged in the mechanical connecting head, the expansion head is a variable-diameter structure and is connected with a quick-change driving assembly, so that the axial movement of the expansion head is driven to realize the expansion or release of the locking steel balls. The application realizes quick and reliable disassembly and replacement between adjacent joints, and improves the modular degree, maintainability and reconstruction efficiency of the mechanical arm.

Description

Technical Field

[0001] This invention relates to the field of joint connection structure technology for robotic arms, and more specifically, to a modular joint quick-change structure, a robotic arm, and a robot. Background Technology

[0002] As a core execution unit in modern intelligent manufacturing, logistics handling, and precision assembly, the flexibility and reconfigurability of robotic arms directly affect the adaptability of production systems. To meet the needs of flexible production with multiple varieties and small batches, the concept of modular robotic arms has emerged—through the rapid combination and reconfiguration of standardized joint units, robotic arm configurations adapted to different task requirements can be quickly built.

[0003] However, existing joint connection technology for robotic arms severely restricts the practical application of this concept. Traditional industrial robotic arms typically employ permanent fixed connections between their joints: high-precision machined integral housings, interference-fit bearings, and non-removable cabling ensure the rigidity and precision of the joints under long-term high-load operation. While this design guarantees stand-alone performance, once the robotic arm is assembled, it forms a fixed configuration and cannot be quickly reconfigured according to changes in the task. Summary of the Invention

[0004] The purpose of this invention is to provide a modular joint quick-change structure, a robotic arm, and a robot to overcome the above-mentioned deficiencies of the prior art.

[0005] This invention is achieved through the following technical solution:

[0006] A modular joint quick-change structure is used to connect adjacent ascending and descending joints. The descending joint is provided with a descending connecting seat, the ascending joint is provided with an ascending connecting seat, and an insertion guide structure is provided between the descending connecting seat and the ascending and descending connecting seats. Electrical, pneumatic and hydraulic lines are connected by plug and socket insertion. The downward connecting seat is provided with a mechanical connecting hole, and the upward connecting seat is provided with a mechanical connecting head that mates with the mechanical connecting hole. The side wall of the mechanical connecting head is provided with several steel ball holes along the circumference. Locking steel balls are provided in the steel ball holes. The inner wall of the mechanical connecting hole is provided with a locking groove that mates with the locking steel balls. The mechanical connecting head is provided with a tightening head inside. The tightening head has a variable diameter structure and is connected to a quick-change drive assembly to drive its axial reciprocating motion to tighten or release the locking steel balls.

[0007] Furthermore, the upper joint is provided with a rotary drive assembly for driving the upper connecting seat to rotate, and a slip ring is provided inside the upper joint. The stator part of the slip ring is fixedly installed, and the rotor part of the slip ring is fixedly connected to the upper connecting seat.

[0008] Furthermore, the rotary drive assembly includes a worm gear, a worm, and a drive element. The worm gear and the worm are rotatably disposed inside the ascending joint and mesh with each other, and the drive element is used to drive the worm to rotate.

[0009] Furthermore, the quick-change drive assembly includes a pull rod, a fixed seat, and a drive screw. The fixed seat is fixedly disposed inside the upper joint, and the drive screw is rotatably disposed inside the fixed seat and axially fixed. One end of the pull rod is connected to the expansion head, and the other end of the pull rod is threadedly engaged with the drive screw. The pull rod is circumferentially fixed to the inner wall of the fixed seat.

[0010] Furthermore, the center of the tensioning head is provided with a T-shaped connecting groove, and the end of the pull rod is provided with a T-shaped connector that mates with the T-shaped connecting groove; a tensioning spring is sleeved on the pull rod, and a spring limiting plate is fixedly connected to the upper connecting seat, with the tensioning spring pressed between the spring limiting plate and the end of the tensioning head.

[0011] Furthermore, the outer wall of the end of the pull rod near the drive screw is provided with an outer flat surface, and the inner wall of the fixing seat is provided with an inner flat surface that mates with the outer flat surface.

[0012] Furthermore, the diameter of the outer end of the steel ball hole is smaller than the diameter of the locking steel ball.

[0013] Furthermore, the insertion guide structure includes guide pins and guide holes that can cooperate with each other. One of the upper connecting seat and the lower connecting seat is provided with a plurality of guide pins along the circumferential direction, and the other is provided with a plurality of guide holes along the circumferential direction.

[0014] The present invention also provides a robotic arm comprising a plurality of joints, wherein adjacent joints are connected by a modular joint quick-change structure as described in any one of the above claims.

[0015] The present invention also provides a robot, including the aforementioned robotic arm.

[0016] The technical solution of the present invention has at least the following advantages and beneficial effects: 1. In this invention, the connection and disconnection of electrical, pneumatic, and hydraulic lines are achieved through the insertion and separation of the plug and socket. The insertion guide structure ensures the alignment accuracy and smooth assembly during insertion. The unique steel ball locking combined with the axial drive expansion head design achieves high-rigidity mechanical locking after connection, and locking and releasing can be quickly completed through simple operation of the drive component. This structure eliminates the complex assembly and wiring processes required for traditional permanent fixed connections, integrating physical connection, electrical, pneumatic, and hydraulic line connection, and mechanical locking into one unit. While ensuring the connection strength, transmission accuracy, and signal reliability between joints, it achieves rapid and reliable disassembly and replacement between adjacent joints, significantly improving the modularity, maintainability, and reconfigurability of the robotic arm, enabling it to flexibly and economically adapt to the flexible production needs of various products.

[0017] 2. In this invention, the rotational drive component satisfies the rotational function of the descending joint relative to the ascending joint. The application of slip rings enables unlimited continuous rotation of the joint, solving the problem of cable entanglement limiting the rotation angle in traditional rotary joints, and greatly expanding the workspace and motion flexibility of the robotic arm. Simultaneously, integrating the drive and rotation functions within the ascending joint allows the entire module below the quick-change connection point (including the ascending connector, descending joint, and subsequent parts) to be driven to rotate as a whole, simplifying system design and enhancing the independence and functionality of the modules. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of a modular joint quick-change structure provided by the present invention; Figure 2 This is a front view of a modular joint quick-change structure provided by the present invention; Figure 3 for Figure 2 AA section view in the middle; Figure 4 for Figure 3 Enlarged view of point B in the image; Figure 5 for Figure 3 Enlarged view of point C in the image; Figure 6 This is a schematic diagram of the ascending joint. Figure 7 for Figure 6 Enlarged view of point D in the image; Figure 8 This is a schematic diagram of the descending joint. Figure 9 for Figure 8 Enlarged view of point E in the image; Reference numerals: 1-Upward joint, 101-Upward connecting seat, 102-Guide pin, 103-Socket, 104-Mechanical connector, 105-Locking ball, 106-Tightening head, 107-Fixed seat, 108-Pull rod, 109-Drive screw, 110-Tightening spring, 111-Spring limit plate, 112-Slip ring, 113-Worm gear, 114-Worm, 115-Upward housing, 2-Downward joint, 201-Downward connecting seat, 202-Guide hole, 203-Plug, 204-Mechanical connecting hole, 205-Downward housing. Detailed Implementation

[0019] refer to Figure 1 as well as Figures 6-9 A modular joint quick-change structure is provided for connecting adjacent upper joint 1 and lower joint 2. Lower joint 2 has a lower connecting seat 201, which is connected to the outer shell (named lower shell 205) of lower joint 2 by screws. Upper joint 1 has an upper connecting seat 101. An insertion guide structure is provided between the lower connecting seat 201 and the upper and lower connecting seats. Electrical, pneumatic, and hydraulic circuit connections are achieved through the insertion of a plug 203 and a socket 103. That is, the insertion and separation of the plug 203 and the socket 103 realizes the connection and disconnection of electrical, pneumatic, and hydraulic circuits, and the insertion guide structure ensures alignment accuracy and smooth assembly during insertion.

[0020] In this embodiment, the plug 203 is disposed on the downlink connector 201, and the socket 103 is disposed on the uplink connector 101. The mating guide structure in this embodiment includes mutually cooperating guide pins 102 and guide holes 202. Specifically, the uplink connector 101 is provided with a plurality of guide pins 102 along the circumference, and the downlink connector 201 is provided with a plurality of guide holes 202 along the circumference. In other embodiments, the guide pins 102 can also be disposed on the downlink connector 201, and the guide holes 202 can be disposed on the uplink connector 101. It is easy to understand that the specific shapes of the guide pins 102 and guide holes 202 are not limited; for example, cylindrical and conical shapes are both acceptable.

[0021] refer to Figures 2-4The downward connecting seat 201 is provided with a mechanical connecting hole 204, and the upward connecting seat 101 is provided with a mechanical connecting head 104 that mates with the mechanical connecting hole 204. Mechanical connection is achieved through the mate of the mechanical connecting head 104 and the mechanical connecting hole 204. Specifically, the side wall of the mechanical connecting head 104 has several steel ball holes along its circumference, and a locking steel ball 105 is provided inside each steel ball hole. Further, in this embodiment, the diameter of the outer end of the steel ball hole is smaller than the diameter of the locking steel ball 105 to ensure that the locking steel ball 105 will not disengage from the steel ball hole. The inner wall of the mechanical connecting hole 204 is provided with a locking groove that mates with the locking steel ball 105. The mechanical connecting head 104 has an expansion head 106 inside. The expansion head 106 has a variable diameter structure and is connected to a quick-change drive assembly to drive its axial reciprocating motion to tighten or release the locking steel ball 105. As is easily understood, in practical applications, when the tightening head 106 moves in one direction, the diameter of the portion contacting the locking ball 105 gradually increases, causing the locking ball 105 to expand outward and press against the locking groove, achieving high-rigidity locking after mechanical connection; when the tightening head 106 moves in the opposite direction, the diameter of the portion contacting the locking ball 105 gradually decreases, causing the tightening head 106 to no longer compress the locking ball 105, achieving unlocking of the mechanical connection. Furthermore, in practical applications, to improve the reliability of the connection, a screw connection can be added between the upper connecting seat 101 and the lower connecting seat 201.

[0022] As can be seen, the quick-change structure provided by this invention eliminates the complex assembly and wiring processes required for traditional permanent fixed connections, integrating physical connections, electrical, pneumatic and hydraulic line connections and mechanical locking into one unit. Under the premise of ensuring the connection strength, transmission accuracy and signal reliability between joints, it realizes quick and reliable disassembly and replacement between adjacent joints, significantly improving the modularity, maintainability and reconfiguration efficiency of the robotic arm, enabling it to flexibly and economically adapt to the flexible production needs of multiple varieties.

[0023] The ascending joint 1 houses a rotary drive assembly for rotating the ascending connecting seat 101. This assembly drives the ascending connecting seat 101, which in turn rotates the descending joint 2, fulfilling its rotational requirements. Furthermore, the ascending joint 1 contains a slip ring 112. The stator of the slip ring 112 is fixedly mounted. In practical applications, the stator of the slip ring 112 is connected to the outer shell of the ascending joint 1 (named ascending shell 115), while the rotor of the slip ring 112 is circumferentially fixed to the ascending connecting seat 101. Notably, the slip ring 112 enables unlimited continuous rotation of the joint, solving the problem of cable entanglement limiting the rotation angle in traditional rotary joints and significantly expanding the workspace and mobility of the robotic arm. Simultaneously, integrating the drive and rotation functions within the ascending joint 1 allows the entire module below the quick-change connection point (including the ascending connecting seat 101, the descending joint 2, and subsequent components) to be driven and rotated as a whole, simplifying system design and enhancing module independence and functionality.

[0024] In this embodiment, the rotary drive assembly includes a worm gear 113, a worm 114, and a drive element. The worm gear 113 and worm 114 are rotatably disposed inside the ascending joint 1 and mesh with each other. The drive element is used to drive the worm 114 to rotate. Preferably, the drive element is a servo motor, which drives the worm 114 to rotate. The worm 114 then drives the worm gear 113 to rotate, thereby driving the ascending connecting seat 101 connected to the worm gear 113 to rotate. In other embodiments, the rotary drive assembly can also use a drive element to drive the ascending connecting seat 101 to rotate through other transmission structures, such as gear transmission or belt transmission.

[0025] refer to Figure 4 and Figure 5In this embodiment, the quick-change drive assembly for reciprocating the expansion head 106 has the following specific structure: it includes a pull rod 108, a fixed seat 107, and a drive screw 109. The fixed seat 107 is fixedly disposed inside the ascending joint 1. The drive screw 109 is rotatably disposed inside the fixed seat 107 and is axially fixed (i.e., the drive screw 109 rotates within the fixed seat 107 but does not move axially). One end of the pull rod 108 is connected to the expansion head 106, and the other end of the pull rod 108 is threadedly engaged with the drive screw. The pull rod 108 is circumferentially fixed to the inner wall of the fixed seat 107 (i.e., the pull rod 108 cannot rotate). By rotating the drive screw 109, the pull rod 108 can be driven to move linearly. In practical applications, an internal hexagonal hole can be provided at the head of the drive screw 109 to facilitate rotation of the drive screw 109 using an internal hexagonal wrench. It should be understood that in other embodiments, the quick-change drive assembly may of course adopt other structures, such as a built-in miniature electric push rod that directly drives the tension head 106 to move axially back and forth; or it may be an electromagnet that moves the tension head 106 by switching on and off power.

[0026] In some embodiments, the tension head 106 can be directly fixedly connected to the pull rod 108. In this embodiment, the tension head 106 has a T-shaped connecting groove at its center, and the end of the pull rod 108 has a T-shaped connector that mates with the T-shaped connecting groove. A tension spring 110 is sleeved on the pull rod 108, and a spring limiting plate 111 is fixedly connected to the upper connecting seat 101. The tension spring 110 is pressed between the spring limiting plate 111 and the end of the tension head 106. That is, when the tension head 106 is sleeved on the pull rod 108, and the pull rod 108 moves toward the drive screw 109, it can drive the tension head 106 to move synchronously, releasing the mechanical lock. When the pull rod 108 moves away from the drive screw 109, the tension head 106 resets under the action of the tension spring, realizing the mechanical lock. It is worth noting that this design, on the one hand, allows the expansion head 106 to float radially relative to the pull rod 108, reducing the requirement for strict coaxiality between the expansion head 106 and the pull rod 108 during assembly and improving assembly processability and reliability; on the other hand, the expansion spring 110 can provide continuous preload, ensuring that even if a slight gap occurs due to vibration or wear in the locked state, the expansion head 106 can still effectively press the steel ball to prevent loosening of the connection, thereby enhancing the vibration resistance and long-term reliability of the locking structure.

[0027] In this embodiment, the circumferential fixation between the pull rod 108 and the inner wall of the fixing seat 107 is achieved as follows: the outer wall of the end of the pull rod 108 near the drive screw 109 has an outer flat surface, and the inner wall of the fixing seat 107 has an inner flat surface that mates with the outer flat surface. In other embodiments, other methods can also be used to achieve the circumferential fixation between the pull rod 108 and the inner wall of the fixing seat 107. For example, the pull rod 108 may adopt a D-shaped shaft structure, and the inner hole of the fixing seat 107 may adopt a corresponding D-shaped hole structure; or one of the outer wall of the pull rod 108 and the inner hole of the fixing seat 107 may be provided with a limiting groove, and the other may be provided with a limiting protrusion that mates with the limiting groove.

[0028] The present invention also provides a robotic arm comprising a plurality of joints, wherein adjacent joints are connected by the aforementioned modular joint quick-change structure. The present invention also provides a robot comprising the aforementioned robotic arm.

[0029] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A modular joint quick-change structure for connecting adjacent ascending and descending joints, characterized in that, The down joint is equipped with a down connecting seat, the up joint is equipped with an up connecting seat, and there is an insertion guide structure between the down connecting seat and the up and down connecting seats. Electrical, pneumatic and hydraulic lines are connected by plug and socket insertion. The downward connecting seat is provided with a mechanical connecting hole, and the upward connecting seat is provided with a mechanical connecting head that mates with the mechanical connecting hole. The side wall of the mechanical connecting head is provided with several steel ball holes along the circumference. Locking steel balls are provided in the steel ball holes. The inner wall of the mechanical connecting hole is provided with a locking groove that mates with the locking steel balls. The mechanical connecting head is provided with a tightening head inside. The tightening head has a variable diameter structure and is connected to a quick-change drive assembly to drive its axial reciprocating motion to tighten or release the locking steel balls.

2. The modular joint quick-change structure according to claim 1, characterized in that, The upper joint is equipped with a rotary drive assembly for driving the upper connecting seat to rotate. The upper joint is equipped with a slip ring, the stator part of which is fixedly installed, and the rotor part of which is fixedly connected to the upper connecting seat.

3. The modular joint quick-change structure according to claim 2, characterized in that, The rotary drive assembly includes a worm gear, a worm, and a drive element. The worm gear and the worm are rotatably disposed inside the ascending joint and mesh with each other. The drive element is used to drive the worm to rotate.

4. The modular joint quick-change structure according to claim 1, characterized in that, The quick-change drive assembly includes a pull rod, a fixed seat, and a drive screw. The fixed seat is fixedly installed inside the upper joint, and the drive screw is rotatably installed inside the fixed seat and axially fixed. One end of the pull rod is connected to the expansion head, and the other end of the pull rod is threadedly engaged with the drive screw. The pull rod is circumferentially fixed to the inner wall of the fixed seat.

5. The modular joint quick-change structure according to claim 4, characterized in that, The center of the tensioning head is provided with a T-shaped connecting groove, and the end of the pull rod is provided with a T-shaped connector that mates with the T-shaped connecting groove; a tensioning spring is sleeved on the pull rod, and a spring limiting plate is fixedly connected to the upper connecting seat, with the tensioning spring pressed between the spring limiting plate and the end of the tensioning head.

6. The modular joint quick-change structure according to claim 4, characterized in that, The outer wall of the pull rod near the drive screw has an outer flat surface, and the inner wall of the fixing seat has an inner flat surface that mates with the outer flat surface.

7. The modular joint quick-change structure according to claim 1, characterized in that, The diameter of the outer end of the ball hole is smaller than the diameter of the locking ball.

8. The modular joint quick-change structure according to claim 1, characterized in that, The insertion guide structure includes guide pins and guide holes that can cooperate with each other. One of the upper connecting seat and the lower connecting seat is provided with a plurality of guide pins along the circumferential direction, and the other is provided with a plurality of guide holes along the circumferential direction.

9. A robotic arm comprising a plurality of joints, characterized in that, Adjacent joints are connected by the modular joint quick-change structure described in any one of claims 1-8.

10. A robot, characterized in that, Includes the robotic arm as described in claim 9.

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