Gripping robot

Abstract

This invention relates to the field of robotic arms, and discloses a gripping robotic arm, comprising a base, a first gripper and a second gripper symmetrically arranged on the base, and an opening and closing drive mechanism for driving the two grippers to open and close synchronously. Each gripper includes a first link group and a second link group hinged to each other, several pulleys arranged on the link groups, a closed flexible belt wound around the pulleys, a pulley drive mechanism, and a link adjustment drive component. The opening and closing drive mechanism drives the two grippers to open and close to fit objects of different sizes; the pulley drive mechanism drives the flexible belt to circulate, which can transport the object from the end of the gripper to the middle to form a wrapping grip; the link adjustment drive component adjusts the angle of the link, synchronously changing the gripping space and the tension of the flexible belt. This invention can adapt to objects of various shapes and materials, provides stable and reliable gripping, and allows adjustment of the object's position and posture while gripping, featuring flexible adaptation, stable gripping, and efficient operation.

Description

Technical Field

[0001] This invention relates to the field of robotic arm technology, and in particular to a gripping robotic arm. Background Technology

[0002] With the rapid development of intelligent manufacturing and the industrial robot industry, gripping robots, as the end effector of robots, can realize automated grasping, handling, and assembly operations. Among them, rigid gripping robots typically adopt parallel gripper or swing gripper structures. The gripper is opened and closed by a drive motor or cylinder. It relies on the normal pressure between the gripper and the surface of the object to generate friction to complete the gripping. This type of rigid robot has a simple structure, simple control logic, and strong load-bearing capacity, and is widely used in regular hard workpieces.

[0003] However, in actual production operations, firstly, rigid gripper robots have poor adaptability to objects of different shapes, sizes, and material hardness. Their contact with objects is mostly point or line contact, with a limited contact area. When facing objects with curved surfaces or irregular contours, the fit is insufficient, failing to form an effective enclosure. For fragile items, soft materials, and other easily damaged objects, the localized stress concentration caused by rigid gripping can easily lead to surface damage, deformation, or even breakage. Furthermore, the effective opening and closing stroke of the grippers is fixed, resulting in a narrow range of adaptable object sizes. Changing grippers is often necessary for different sizes of objects being gripped, leading to high changeover costs and long downtime.

[0004] Secondly, the gripping force of a rigid robotic arm relies on the positive pressure generated by the opening and closing of the grippers and the friction of the contact surface. When the surface of the object is smooth, there is mechanical vibration during the operation, or the robotic arm starts, stops, or turns at high speed, the friction of the contact surface weakens, causing the object to slip and fall off. Moreover, the gripping force area is concentrated at the end of the grippers, and the overall force on the object is uneven. During the handling process, it is easy to deflect or loosen, and it is impossible to form a stable gripping state.

[0005] Furthermore, the gripping point of traditional rigid grippers is fixed at the tip of the gripper. Once the object is gripped, its position cannot be adjusted inside the gripper, and it is always at the extended end of the gripper. This not only causes the gripping center of gravity to shift outward and reduces the overall gripping stability, but also makes it impossible for the robot to adjust the gripping posture or to store the object inside the gripper to avoid obstacles in the surrounding environment when the operation requires adjustment. It is necessary to use an external positioning mechanism or vision system for secondary positioning and gripping, which increases the system complexity and operation cycle.

[0006] To improve the adaptability of rigid gripping, existing technologies have developed solutions such as soft robotic arms and airbag-type flexible grippers. These solutions improve the fit with the object surface through flexible deformation. However, these solutions generally suffer from weak load capacity, low precision in gripping force control, and slow response speed. They also lack the ability to adjust the position of the object after gripping, and cannot simultaneously meet the multiple requirements of flexible adaptation, stable gripping, and efficient operation.

[0007] It is evident that existing technologies still need improvement and enhancement. Summary of the Invention

[0008] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a gripping manipulator that can adapt to various object sizes and shapes, achieve reliable gripping, and operate efficiently in complex environments.

[0009] To achieve the above objectives, the present invention adopts the following technical solution: A gripping manipulator includes a base, a first gripper, a second gripper, and an opening / closing drive mechanism. The opening / closing drive mechanism is mounted on the base and drives the first and second grippers to open and close synchronously relative to each other. The first and second grippers are symmetrically arranged and each includes a first linkage group, a second linkage group, several pulleys, a closed flexible belt, a pulley drive mechanism, and a linkage adjustment drive component. The first and second linkage groups are hinged to each other to form a two-bar structure that can rotate relative to each other. Several pulleys are respectively arranged at the hinge points of the first and second linkage groups, the free ends of the first and second linkage groups, and the free ends of the second linkage groups. The flexible belt is wound around all the pulleys to form a cyclic gripping working surface that rotates with the pulleys. The pulley drive mechanism drives the corresponding pulleys to rotate. The linkage adjustment drive component drives the first and second linkage groups to rotate relative to each other to adjust the angle between the first and second linkage groups.

[0010] Furthermore, the opening and closing drive mechanism includes an opening and closing drive member disposed on the back of the base and whose output end passes through the front and rear side walls of the base, a first transmission gear that is tractively connected to the output end of the opening and closing drive member and located on the front of the base, and a second transmission gear that meshes with the first transmission gear; the opening and closing drive member is used to drive the first gripper to rotate, and to drive the second gripper to rotate synchronously in the opposite direction through gear meshing.

[0011] Further, the pulley includes a first pulley, a second pulley, and a third pulley arranged from top to bottom; the first connecting rod assembly includes a first connecting rod fixedly connected to the first transmission gear or the second transmission gear and extending obliquely outward, a second connecting rod disposed in front of the first connecting rod and extending obliquely outward, and a first crossbar integrally formed with the first connecting rod and used to connect the lower end of the second connecting rod; the second pulley is disposed on the first crossbar, and the centers of the first transmission gear and the second transmission gear are respectively connected to the first pulley through a first bearing; the pulley drive mechanism is disposed on the front side of the upper end of the second connecting rod, and the pulley drive mechanism is used to drive the first pulley to rotate.

[0012] Furthermore, a clearance hole is provided on the second connecting rod, and a second bearing is provided in the clearance hole. The output end of the pulley drive mechanism passes through the center of the second bearing and is connected to the first pulley for transmission.

[0013] Furthermore, a connecting shaft is provided on the back of the first pulley, and the connecting shaft is connected to the first transmission gear or the second transmission gear through the first bearing; a keyway is provided on the front of the first pulley, and the pulley drive mechanism is a pulley drive motor, the output end of the pulley drive motor is connected to the first pulley through the keyway.

[0014] Furthermore, the second link includes a laterally extending mounting plate and an extension plate integrally formed with the lower surface of the mounting plate; the front side of the mounting plate is used to mount the pulley drive mechanism, and the lower end of the extension plate is fixedly connected to the first crossbar.

[0015] Furthermore, the second linkage assembly includes a third linkage whose upper end is located on the back of the first linkage and extends obliquely inward, a fourth linkage whose upper end is located on the front of the second linkage and extends obliquely inward, and a second crossbar integrally formed with the third linkage and used to connect the lower end of the fourth linkage; the second crossbar is provided with the third pulley; the linkage adjustment drive is a linkage adjustment drive motor, which is located on the back of the third linkage, and the output end of the linkage adjustment drive motor is connected to the upper end of the third linkage.

[0016] Furthermore, the second linkage assembly also includes a first insertion hole disposed at the front end of the second crossbar, and a first pin disposed in the first insertion hole; the lower end of the fourth linkage is provided with a first through hole, the end of the second crossbar passes through the first through hole, and the first pin is located in front of the fourth linkage.

[0017] Furthermore, the first link assembly also includes a second insertion hole disposed at the front end of the first crossbar, and a second pin disposed in the second insertion hole; the upper end of the fourth link is provided with a second through hole, the end of the first crossbar passes through the second through hole, and the second pin is located in front of the fourth link.

[0018] Furthermore, two counterweight limiting blocks are provided at the rear of the base, and each of the two counterweight limiting blocks has a threaded hole at its center. The base has two mounting holes, and each of the two mounting holes has a third bearing. The back of the first transmission gear and the second transmission gear are each provided with an integrally formed threaded post, which passes through the corresponding third bearing and is threadedly connected to the corresponding threaded hole.

[0019] Beneficial effects: This invention provides a gripping robot, comprising a base, a first gripper and a second gripper symmetrically arranged on the base, and an opening and closing drive mechanism for driving the two grippers to open and close synchronously relative to each other. Each gripper consists of a first link group and a second link group hinged to each other, several pulleys, a closed flexible belt, a pulley drive mechanism, and a link adjustment drive component. The synchronous opening and closing of the two grippers is achieved through the opening and closing drive mechanism in conjunction with gear meshing transmission. Combined with a flexible gripping working surface and a dynamically adjustable link angle structure, it achieves the advantage of a wide gripping adaptability range, adapting to objects of different sizes, shapes, and material hardness. The flexible belt conforms to the object's contour through elastic deformation, avoiding pressure damage and deformation caused by rigid gripping. Simultaneously, adjusting the link angle can change the internal space of the grippers and the tension of the flexible belt, allowing for the handling of multiple material specifications without changing the grippers, effectively reducing changeover costs. The flexible belt, driven by a pulley drive mechanism, circulates along the pulley path, achieving strong gripping stability. It transports objects initially held by the gripper's end to the middle, forming a wraparound grip. This shifts the center of gravity inward and distributes force more evenly, improving vibration and impact resistance and effectively preventing slippage and deflection during transport. Independent control and differential speed coordination of the two pulley drive mechanisms on both sides achieve high operational efficiency. The gripping position and posture can be adjusted while maintaining the grip, eliminating the need for secondary gripping with external positioning mechanisms. Objects can also be stored inside the grippers to avoid environmental obstacles, simplifying system configuration and shortening the work cycle. Attached Figure Description

[0020] Figure 1 A schematic diagram of the structure of a gripping robotic hand. Figure 1 ; Figure 2 A schematic diagram of the structure of a gripping robotic hand. Figure 2 ; Figure 3For the unfolding of a gripping robotic hand Figure 1 ; Figure 4 For the unfolding of a gripping robotic hand Figure 2 .

[0021] Key component symbols: 1-Base; 11-Mounting hole; 2-First gripper; 21-First linkage group; 211-First link; 212-Second link; 2121-Mounting plate; 2122-Extension plate; 2123-Clearing hole; 213-First crossbar; 214-Second insertion hole; 22-Second linkage group; 221-Third link; 222-Fourth link; 2221-First through hole; 2222-Second through hole; 223-Second crossbar; 224-First insertion hole; 2 3-Pulley; 231-First pulley; 2311-Connecting shaft; 2312-Keyway; 232-Second pulley; 233-Third pulley; 24-Flexible belt; 25-Pulley drive mechanism; 26-Linkage adjustment drive component; 3-Second gripper; 4-Opening and closing drive mechanism; 41-Opening and closing drive component; 42-First transmission gear; 421-Threaded column; 43-Second transmission gear; 5-First bearing; 6-Second bearing; 7-Counterweight limit block; 71-Threaded hole; 8-Third bearing. Detailed Implementation

[0022] This invention provides a gripping robotic hand. To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the scope of protection of the invention.

[0023] Please see Figures 1-4 This invention provides a gripping manipulator, including a base 1, a first gripper 2, a second gripper 3, and an opening / closing drive mechanism 4. The opening / closing drive mechanism 4 is disposed on the base 1 and is used to drive the first gripper 2 and the second gripper 3 to synchronously open and close relative to each other. The first gripper 2 and the second gripper 3 are symmetrically arranged left and right, and each includes a first link group 21, a second link group 22, several pulleys 23, a closed flexible belt 24, a pulley drive mechanism 25, and a link adjustment drive component 26. The first link group 21 and the second link group 22 are hinged to each other to form a responsive gripper. The system comprises a rotating two-bar linkage; several pulleys 23 are respectively arranged at the hinge of the first link group 21 and the second link group 22, the free end of the first link group 21, and the free end of the second link group 22; a flexible belt 24 is wound around all the pulleys 23 to form a cyclic clamping working surface that rotates with the pulleys 23; a pulley drive mechanism 25 is used to drive the corresponding pulleys 23 to rotate; and a link adjustment drive 26 is used to drive the first link group 21 and the second link group 22 to rotate relative to each other to adjust the included angle between the first link group 21 and the second link group 22.

[0024] In the initial standby state, the opening and closing drive mechanism 4 drives the first gripper 2 and the second gripper 3 to open to a preset opening angle. The linkage adjustment drive component 26 adjusts the included angle between the first linkage group 21 and the second linkage group 22 to the initial position, so that the flexible belts 24 wrapped around each pulley 23 maintain basic tension. When the robot moves to the corresponding workstation of the object to be grasped, the opening and closing drive mechanism 4 outputs power, driving the first gripper 2 and the second gripper 3 to rotate synchronously in opposite directions. The flexible belts 24 on the two grippers gradually approach and contact the surface of the object. Since the flexible belts 24 have their own deformation capability, they can adapt to the outer contour of the object and form surface contact with the object surface, completing the initial clamping of the object and avoiding the problem of local stress concentration caused by rigid clamping. After initial clamping, the pulley drive mechanisms 25 on the two grippers start synchronously, driving the corresponding pulleys 23 to rotate, which in turn drives the closed flexible belts 24 to circulate along the arrangement path of the pulleys 23. The flexible belts 24 on both sides rotate in opposite directions synchronously towards the inside of the grippers, and rely on the friction of the contact surface to move the object from the free end of the gripper to the middle area of ​​the gripper until the object is in the center gripping position of the two grippers. At this time, the object is wrapped by the flexible belts 24 on both sides, and the center of gravity of the gripping shifts inward. Compared with the traditional end gripping method, the contact area is larger and the force is more balanced, which can effectively improve the stability of the grip and reduce the risk of the object slipping. During the clamping process, the linkage adjustment drive 26 can output power to drive the first linkage group 21 and the second linkage group 22 to rotate relative to each other around the hinge. By changing the included angle of the two linkage groups, the center distance of the pulleys 23 is adjusted, thereby changing the tension of the flexible belt 24 and the internal accommodating space of the grippers. For objects of different sizes and material hardness, the clamping space and clamping force can be matched by adjusting the included angle of the linkages, which is suitable for various gripping objects such as fragile items and soft materials. At the same time, the pulley drive mechanisms 25 on both sides can also adjust the clamping contact position and posture of the object without loosening it through differential rotation, which can meet the needs of different working scenarios. When the robot arm moves the object to the target workstation, the opening and closing drive mechanism 4 drives in the opposite direction, causing the first gripper 2 and the second gripper 3 to rotate and open synchronously in opposite directions. At the same time, the pulley drive mechanism 25 can cooperate with the reverse rotation to assist the object in detaching, completing the object release action.

[0025] Please see Figure 3 and Figure 4In some embodiments, the opening and closing drive mechanism 4 includes an opening and closing drive member 41 disposed on the back of the base 1 and whose output end passes through the front and rear side walls of the base 1, a first transmission gear 42 connected to the output end of the opening and closing drive member 41 and located on the front of the base 1, and a second transmission gear 43 meshing with the first transmission gear 42. The opening and closing drive member 41 is used to drive the first gripper 2 to rotate, and drives the second gripper 3 to rotate synchronously in the opposite direction through gear meshing. The opening and closing drive mechanism 4 is used to provide driving force for the opening and closing action of the two grippers and to ensure the synchronicity and centering of the movement of the two grippers. The opening and closing drive member 41 is fixedly installed on the back of the base 1, and its output end passes forward through the front and rear side walls of the base 1 and is connected to the first transmission gear 42 located on the front of the base 1. This layout allows the drive body to be placed at the rear to balance the weight of the gripper side, optimize the overall center of gravity distribution, and concentrate the transmission meshing structure on the front of the base 1 to improve the structural compactness. During operation, the opening / closing drive component 41 outputs torque and drives the first transmission gear 42 to rotate synchronously. Since the first transmission gear 42 is fixedly connected to the upper end of the first gripper 2, the first transmission gear 42 will synchronously drive the first gripper 2 to rotate around its axis. At the same time, the second transmission gear 43, which meshes with the first transmission gear 42, will rotate synchronously in the opposite direction as the first transmission gear 42 rotates. The second transmission gear 43 is fixedly connected to the upper end of the second gripper 3, thereby driving the second gripper 3 to rotate synchronously around its axis in the opposite direction to the first gripper 2. Ultimately, this achieves synchronous closing of the two grippers towards each other or synchronous opening of the two grippers in opposite directions. By transmitting power through a pair of meshing transmission gears, the opening and closing angles of the two grippers can be strictly guaranteed to be consistent and the motion response synchronized. This ensures that the clamping force is symmetrically applied to both sides of the object to be gripped, guaranteeing the centering of the object during the gripping process. At the same time, the gear transmission has the characteristics of high transmission accuracy, strong load-bearing capacity, and stable transmission efficiency, and can reliably transmit the driving force required for the gripping operation.

[0026] Please see Figure 1 In some embodiments, the pulley 23 includes a first pulley 231, a second pulley 232, and a third pulley 233 arranged from top to bottom; see also Figures 2-4The first linkage group 21 includes a first link 211 fixedly connected to the first transmission gear 42 or the second transmission gear 43 and extending obliquely outward, a second link 212 disposed in front of the first link 211 and extending obliquely outward, and a first crossbar 213 integrally formed with the first link 211 and used to connect the lower end of the second link 212; a second pulley 232 is disposed on the first crossbar 213, and the centers of the first transmission gear 42 and the second transmission gear 43 are respectively connected to the first pulley 231 through the first bearing 5; the pulley drive mechanism 25 is disposed on the front of the upper end of the second link 212, and the pulley drive mechanism 25 is used to drive the first pulley 231 to rotate. The pulley 23 and the first linkage group 21 together constitute the rigid support frame of the upper half of the gripper and the active transmission structure of the flexible belt 24, providing a structural basis and power input for the opening and closing action of the gripper and the cyclic conveying of the flexible belt 24. The first connecting rod 211 extends obliquely outward and its upper end is fixedly connected to the corresponding transmission gear. As the main bearing arm of the gripper, it directly bears the torque of the opening and closing drive, driving the entire gripper to swing and open around the axis of the transmission gear. The second connecting rod 212 is arranged parallel to the front of the first connecting rod 211, and its lower end is connected to the first crossbar 213 integrally formed with the first connecting rod 211. The three together form a frame-shaped rigid frame, which improves the structural strength and torsional resistance of the upper half of the gripper. Three pulleys 23 are arranged from top to bottom along the extension direction of the connecting rod assembly, forming a triangular support belt drive wheel system, providing tension support and steering guidance for the closed flexible belt 24; the first pulley 231 is mounted at the center of the first transmission gear 42 / second transmission gear 43 through the first bearing 5, and is coaxially arranged with the first transmission gear 42 / second transmission gear 43 and can rotate independently of each other, thereby decoupling the opening and closing swing motion of the gripper as a whole from the rotational conveying motion of the first pulley 231 itself. The two sets of motion share the same axis of rotation but do not interfere with each other, simplifying the structural layout while avoiding motion interference. The second pulley 232 is mounted on the first crossbar 213 and serves as a support and steering wheel for the middle section of the flexible belt 24, ensuring the flatness and tension consistency of the working surface of the flexible belt 24. The pulley drive mechanism 25 is fixedly mounted on the front of the upper end of the second connecting rod 212, and its output end is directly connected to the first pulley 231 for transmission. During operation, the output torque drives the first pulley 231 to rotate, and the first pulley 231 acts as the driving wheel to drive the flexible belt 24 to circulate along the wheel system path. It works in conjunction with the third pulley 233 at the lower end to complete the steering support, and finally realizes the stable circulatory conveying of the flexible belt 24, providing power for the position adjustment of the object in the gripper.

[0027] Please see Figure 3 and Figure 4In some embodiments, a clearance hole 2123 is provided on the second connecting rod 212, and a second bearing 6 is disposed in the clearance hole 2123. The output end of the pulley drive mechanism 25 passes through the center of the second bearing 6 and is connected to the first pulley 231 for transmission. The clearance hole 2123 allows the pulley drive mechanism 25 to be externally mounted on the front of the second connecting rod 212, and the output end can directly extend through the body of the second connecting rod 212 to the inner side to dock with the first pulley 231. Direct power transmission can be achieved without the need for additional intermediate transmission components. The space on both sides of the second connecting rod 212 is fully utilized to realize the layered arrangement of the drive component and the transmission wheel system, simplifying the transmission structure. The second bearing 6, which is embedded in the clearance hole 2123, is coaxially engaged with the output end of the pulley drive mechanism 25. After passing through the inner ring of the second bearing 6, the output end is connected to the first pulley 231 for transmission. The second bearing 6 can provide stable radial support for the output shaft, offset the radial load on the first pulley 231 during the tensioning of the flexible belt 24 and the transmission process, and at the same time reduce the frictional resistance and wear of the output shaft during rotation, so as to ensure the coaxial operation accuracy of the output shaft and the first pulley 231.

[0028] Please see Figure 3 and Figure 4 In some embodiments, a connecting shaft 2311 is provided on the back of the first pulley 231. The connecting shaft 2311 is connected to the first transmission gear 42 or the second transmission gear 43 through the first bearing 5. A keyway 2312 is provided on the front of the first pulley 231. The pulley drive mechanism 25 is a pulley drive motor. The output end of the pulley drive motor is connected to the first pulley 231 through the keyway 2312. The connecting shaft 2311 is integrally provided on the back of the first pulley 231. The connecting shaft 2311 is rotated with the corresponding transmission gear through the first bearing 5, so that the first pulley 231 can rotate freely around the central axis of the transmission gear. When the transmission gear drives the entire gripper to complete the opening and closing swing, the first pulley 231 can maintain its own independent rotation state and does not rotate synchronously with the transmission gear. This decouples the opening and closing swing motion of the gripper from the conveying motion of the first pulley 231 driving the flexible belt 24. The two sets of motion share the same axis of rotation but do not interfere with each other. The first pulley 231 has a keyway 2312 on its front side. The output end of the pulley drive motor forms a circumferentially fixed transmission connection with the first pulley 231 through the keyway 2312. The key connection stabilizes the torque transmission, ensuring the positional accuracy and response speed of the flexible belt 24. At the same time, this connection is compact and easy to assemble, which can effectively improve the assembly efficiency and maintenance convenience of the belt drive system. Combined with the bearing support on the back side, it forms a double-end supported shaft structure, so that the first pulley 231 is subjected to balanced force when it is running.

[0029] Please see Figure 3In some embodiments, the second connecting rod 212 includes a laterally extending mounting plate 2121 and an extension plate 2122 integrally formed with the lower surface of the mounting plate 2121. The front side of the mounting plate 2121 is used to mount the pulley drive mechanism 25, and the lower end of the extension plate 2122 is fixedly connected to the first crossbar 213. The laterally extending mounting plate 2121 provides a flat and sufficient front mounting area, and the pulley drive mechanism 25 can be directly fixed to the front side of the mounting plate 2121. The lateral arrangement can be adapted to the radial mounting dimensions of the drive motor, making the installation force of the drive component more balanced. The extension plate 2122, integrally formed with the lower surface of the mounting plate 2121, extends obliquely outward along the gripper, and its lower end is connected to the first crossbar 213. This allows the load generated during the gripper clamping operation to be smoothly transmitted to the first crossbar 213 and the first connecting rod 211, forming a continuous and stable force-bearing path and ensuring the overall structural rigidity of the gripper.

[0030] Please see Figures 3-4In some embodiments, the second linkage group 22 includes a third linkage 221 with its upper end located on the back of the first linkage 211 and extending obliquely inward, a fourth linkage 222 with its upper end located on the front of the second linkage 212 and extending obliquely inward, and a second crossbar 223 integrally formed with the third linkage 221 and used to connect the lower end of the fourth linkage 222; the second crossbar 223 is provided with the third pulley 233; the linkage adjustment drive component 26 is a linkage adjustment drive motor, which is located on the back of the third linkage 221, and the output end of the linkage adjustment drive motor is connected to the upper end of the third linkage 221. The second linkage group 22 and the first linkage group 21 are hinged to each other to form an adjustable two-link structure of the gripper, and at the same time support the lower pulley 23 and the angle adjustment drive component. It is a key structural unit for realizing the tension adjustment of the flexible belt 24 and the dynamic adaptation of the clamping space. The third link 221 and the fourth link 222 are arranged in a staggered manner, with their upper ends hinged to the back of the first link 211 and the front of the second link 212, respectively. Their lower ends are connected to the second crossbar 223, which is integrally formed with the third link 221, together forming a closed frame-type rigid frame. The symmetrical layout of the front and rear double links can evenly bear the radial load during clamping operations, avoiding the problem of eccentric torsion caused by unilateral force, and effectively improving the structural rigidity and fatigue resistance of the lower section of the gripper. The second crossbar 223 is equipped with a third pulley 233, which serves as the support and steering wheel for the lower end of the flexible belt 24. Together with the first pulley 231 at the upper end and the second pulley 232 in the middle section, it forms a triangular pulley support system, providing complete tension support and steering guidance for the closed flexible belt 24, ensuring the flatness and tension consistency of the inner clamping working surface of the flexible belt 24. The linkage adjustment drive motor is rear-mounted and fixed on the back of the third linkage 221. This fully utilizes the unused space on the back of the gripper and avoids structural interference with the pulley 23, flexible belt 24, and the object being gripped. Its output end is connected to the upper hinge shaft of the third linkage 221. During operation, the output torque can directly drive the entire second linkage group 22 to swing relative to the first linkage group 21 around the hinge axis. By changing the angle between the first linkage group 21 and the second linkage group 22, the center distance between the third pulley 233 and the other pulleys is adjusted synchronously, thereby changing the tension of the flexible belt 24 and adjusting the effective accommodating space inside the gripper. This allows it to adapt to gripping objects of different sizes and precisely adjust the gripping force to meet the flexible gripping needs of fragile, soft, and other materials.

[0031] Please see Figure 1 , Figure 3 and Figure 4In some embodiments, the second link assembly 22 further includes a first insertion hole 224 disposed at the front end of the second crossbar 223, and a first pin disposed in the first insertion hole 224; the lower end of the fourth link 222 is provided with a first through hole 2221, the end of the second crossbar 223 passes through the first through hole 2221, and the first pin is located in front of the fourth link 222. This structure is a detachable hinged limiting structure at the lower end of the second link assembly 22, used to realize the rotational connection and axial positioning of the fourth link 222 and the second crossbar 223. During assembly, the front end of the second crossbar 223 passes through the first through hole 2221 at the lower end of the fourth link 222, allowing the fourth link 222 to rotate freely around the axis of the second crossbar 223. This works in conjunction with the hinge structure at the upper end to ensure that the entire second link assembly 22 can swing smoothly around the hinge axis, thereby adjusting the angle of the link. Subsequently, the first pin is inserted into the first insertion hole 224 at the end of the second crossbar 223. The first pin is positioned in front of the fourth link 222, which can axially limit the fourth link 222 and maintain the structural integrity of the frame structure formed by the third link 221, the second crossbar 223, and the fourth link 222. The device adopts a pin-type detachable limiting structure, which makes assembly and disassembly simple. When it is necessary to replace the flexible belt 24, repair the third pulley 233, or clean the inside of the gripper, the fourth link 222 can be removed from the second crossbar 223 simply by pulling out the first pin. The side frame of the link assembly can be opened without disassembling the transmission gear, drive motor and other core components at the upper end of the gripper. This reduces the difficulty of daily maintenance and replacement of vulnerable parts and improves the operation and maintenance convenience of the robot.

[0032] Please see Figure 3 and Figure 4In some embodiments, the first link assembly 21 further includes a second insertion hole 214 disposed at the front end of the first crossbar 213, and a second pin disposed in the second insertion hole 214; the upper end of the fourth link 222 is provided with a second through hole 2222, the end of the first crossbar 213 passes through the second through hole 2222, and the second pin is located in front of the fourth link 222. This structure is a detachable hinged limiting structure between the upper end of the second link assembly 22 and the first link assembly 21, corresponding vertically to the first pin limiting structure at the lower end, together forming a stable rotating joint and axial limiting system of the two-link structure. During assembly, the front end of the first crossbar 213 is inserted into the second through hole 2222 at the upper end of the fourth link 222, allowing the upper end of the fourth link 222 to rotate freely around the axis of the first crossbar 213, cooperating with the rotating joint formed by the lower end around the second crossbar 223, ensuring that the second link assembly 22 as a whole can swing smoothly relative to the first link assembly 21 along a unified axis of rotation. The second pin is inserted into the second insertion hole 214 at the end of the first crossbar 213 and is positioned in front of the fourth link 222, thus axially limiting the upper end of the fourth link 222 and restricting the axial movement of the fourth link 222 along the first crossbar 213. Together with the first pin at the lower end, it maintains the stability of the frame structure in which the first link group 21 and the second link group 22 are arranged in front and behind. This structure also adopts a pin-type detachable design, forming a unified disassembly and assembly method with the lower limiting structure. When it is necessary to replace the flexible belt 24, inspect the third pulley 233, or clean the internal space of the gripper, the upper and lower pins can be pulled out at the same time to quickly separate the fourth connecting rod 222 from the connecting rod assembly, opening the installation space on the side of the gripper. There is no need to disassemble the transmission gear, drive motor and other core components at the upper end of the gripper, which effectively reduces the complexity of operation and maintenance and improves the efficiency of replacing vulnerable parts and daily maintenance. At the same time, the pin-hinged structure is simple to process and assemble, and the rotational fit accuracy is easy to ensure, which can control the manufacturing cost while ensuring structural strength and smooth operation.

[0033] Please see Figures 2-4In some embodiments, two counterweight limiting blocks 7 are provided at the rear of the base 1, and each of the two counterweight limiting blocks 7 has a threaded hole 71 at its center. Two mounting holes 11 are provided on the base 1, and a third bearing 8 is provided in each of the two mounting holes 11. An integrally formed threaded post 421 is provided on the back of both the first transmission gear 42 and the second transmission gear 43. The threaded post 421 passes through the corresponding third bearing 8 and is threadedly connected to the corresponding threaded hole 71. Mounting holes 11 are provided on the base 1 at the positions corresponding to the two transmission gears, and the third bearing 8 is embedded in the holes. The integrally formed threaded post 421 on the back of the first transmission gear 42 and the second transmission gear 43 passes rearward through the inner ring of the corresponding third bearing 8, providing stable radial support to the transmission gears and ensuring the meshing coaxiality and transmission accuracy of the two gears. After the rear end of the threaded column 421 extends out of the third bearing 8, it is threadedly connected to the threaded hole 71 at the center of the corresponding counterweight limiting block 7 at the rear of the base 1. This secures the counterweight limiting block 7 to the back of the base 1 and simultaneously provides axial restraint to the transmission gear, limiting its forward and backward movement along the axial direction. The two counterweight limiting blocks 7, located on the back of the base 1, balance the total weight of the gripper, drive motor, and transmission components on the front of the base 1, causing the overall center of gravity of the robot to shift back towards the center of the base 1. This effectively reduces the overturning moment caused by the frontal off-center load, alleviates the load bias at the robot's end effector, and improves the dynamic balance performance of the robot during its movement.

[0034] The working principle of this invention will be further explained below with reference to the complete working process: Initial standby state: The opening and closing drive mechanism 4 drives the first gripper 2 and the second gripper 3 to open to the preset angle, the connecting rod adjustment drive component 26 adjusts the angle between the two connecting rods to the initial position, and the flexible belt 24 maintains the basic tension.

[0035] Initial gripping: The robotic arm moves to the front of the object to be gripped, and the opening and closing drive 41 drives the two grippers to rotate in opposite directions. The flexible strips 24 on both sides contact the surface of the object and produce elastic deformation, conforming to the outline of the object and completing the initial gripping.

[0036] Conveying and holding: The pulley drive mechanism 25 starts, and the pulley drive motors on both sides rotate synchronously and in opposite directions, driving the flexible belts 24 on both sides to rotate inwards towards the inside of the gripper. Through friction, the object is moved from the end of the gripper to the middle of the gripper. When the object moves to the middle of the gripper, the pulley drive mechanism 25 stops, and the object is wrapped and held by the flexible belts 24 on both sides. The center of gravity shifts inward, forming a stable holding state.

[0037] Clamping force adjustment: Based on the material and weight of the object and the operational requirements, the linkage adjustment drive 26 drives the second linkage group 22 to rotate, adjusts the included angle of the two linkages, changes the tension of the flexible belt 24, and achieves precise adjustment of the clamping force; the tension can be reduced for fragile objects and increased for heavy objects.

[0038] Attitude adjustment: If it is necessary to adjust the clamping attitude of the object, the differential rotation of the drive motors of the two pulleys can be controlled to make the object rotate or move while it is clamped, thereby adjusting the contact position and gripping attitude, and allowing for a second gripping without releasing.

[0039] Release of object: After reaching the target position, the opening and closing drive mechanism 4 drives the two grippers to rotate in opposite directions and open. The pulley drive mechanism 25 can cooperate to rotate in the opposite direction to assist the object in detaching and complete the release action.

[0040] In summary, this invention uses the opening and closing drive mechanism 4 in conjunction with gear meshing to drive the double grippers to open and close synchronously. Combined with the synergistic effect of the two linkages hinged on the grippers, the closed flexible belt 24 arranged around the multi-pulley 23, the independent pulley drive mechanism 25, and the linkage adjustment drive component 26, it achieves flexible and adaptable gripping of objects of different sizes, shapes, and materials, resulting in a wide gripping range, strong gripping stability, and high work efficiency. The flexible belt 24, serving as the clamping working surface, can conform to the contour of the object through elastic deformation, avoiding local stress damage caused by rigid clamping, and is suitable for irregularly shaped, fragile, and soft materials. With the linkage angle adjustment, the clamping space and the tension of the flexible belt 24 can be changed simultaneously, allowing for the handling of objects of various sizes without changing the grippers. The cyclic conveying of the flexible belt 24 can transfer the object from the end of the gripper to the middle to form a wrap-around grip, shifting the center of gravity inward and making the force more balanced, effectively reducing the risk of the object slipping. At the same time, the pulley drive mechanism 25 on both sides can adjust the clamping position and posture of the object through differential speed control, adapting to different operation requirements without secondary gripping. The overall structure is compact and the transmission is stable, which can meet the needs of automated gripping and handling under complex working conditions.

[0041] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0042] Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0043] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows for communication; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0044] It is understood that those skilled in the art can make equivalent substitutions or changes to the technical solution and inventive concept of the present invention, and all such changes or substitutions should fall within the protection scope of the present invention.

Claims

1. A gripping robotic hand, characterized in that, The device includes a base, a first gripper, a second gripper, and an opening / closing drive mechanism. The opening / closing drive mechanism is mounted on the base and drives the first and second grippers to open and close synchronously relative to each other. The first and second grippers are symmetrically arranged and each includes a first linkage group, a second linkage group, several pulleys, a closed flexible belt, a pulley drive mechanism, and a linkage adjustment drive component. The first and second linkage groups are hinged to each other to form a two-bar structure that can rotate relative to each other. Several pulleys are respectively arranged at the hinge point of the first and second linkage groups, the free end of the first linkage group, and the free end of the second linkage group. The flexible belt is wound around all the pulleys to form a cyclic clamping working surface that rotates with the pulleys. The pulley drive mechanism drives the corresponding pulley to rotate. The linkage adjustment drive component drives the first and second linkage groups to rotate relative to each other to adjust the angle between the first and second linkage groups.

2. The gripping robotic hand according to claim 1, characterized in that, The opening and closing drive mechanism includes an opening and closing drive member disposed on the back of the base and whose output end passes through the front and rear side walls of the base, a first transmission gear that is pulsatorically connected to the output end of the opening and closing drive member and located on the front of the base, and a second transmission gear that meshes with the first transmission gear; the opening and closing drive member is used to drive the first gripper to rotate, and drives the second gripper to rotate synchronously in the opposite direction through gear meshing.

3. The gripping robotic hand according to claim 2, characterized in that, The pulleys include a first pulley, a second pulley, and a third pulley arranged from top to bottom; the first connecting rod assembly includes a first connecting rod fixedly connected to the first transmission gear or the second transmission gear and extending obliquely outward, a second connecting rod disposed in front of the first connecting rod and extending obliquely outward, and a first crossbar integrally formed with the first connecting rod and used to connect the lower end of the second connecting rod; the second pulley is disposed on the first crossbar, and the centers of the first transmission gear and the second transmission gear are respectively connected to the first pulley through a first bearing; the pulley drive mechanism is disposed on the front side of the upper end of the second connecting rod, and the pulley drive mechanism is used to drive the first pulley to rotate.

4. The gripping robotic hand according to claim 3, characterized in that, The second connecting rod has a clearance hole, in which a second bearing is installed. The output end of the pulley drive mechanism passes through the center of the second bearing and is connected to the first pulley for transmission.

5. The gripping robotic hand according to claim 4, characterized in that, The first pulley has a connecting shaft on its back side, which is connected to the first transmission gear or the second transmission gear via the first bearing; the first pulley has a keyway on its front side, and the pulley drive mechanism is a pulley drive motor, the output end of which is connected to the first pulley via the keyway.

6. The gripping robotic hand according to claim 3, characterized in that, The second link includes a laterally extending mounting plate and an extension plate integrally formed with the lower surface of the mounting plate; the front of the mounting plate is used to mount the pulley drive mechanism, and the lower end of the extension plate is fixedly connected to the first crossbar.

7. The gripping robotic hand according to claim 3, characterized in that, The second linkage assembly includes a third linkage whose upper end is located on the back of the first linkage and extends obliquely inward, a fourth linkage whose upper end is located on the front of the second linkage and extends obliquely inward, and a second crossbar integrally formed with the third linkage and used to connect the lower end of the fourth linkage; the second crossbar is provided with the third pulley; the linkage adjustment drive is a linkage adjustment drive motor, which is located on the back of the third linkage, and the output end of the linkage adjustment drive motor is connected to the upper end of the third linkage.

8. The gripping robotic hand according to claim 7, characterized in that, The second linkage group further includes a first insertion hole disposed at the front end of the second crossbar, and a first pin disposed in the first insertion hole; the lower end of the fourth linkage is provided with a first through hole, the end of the second crossbar passes through the first through hole, and the first pin is located in front of the fourth linkage.

9. The gripping robotic hand according to claim 8, characterized in that, The first link assembly further includes a second insertion hole disposed at the front end of the first crossbar, and a second pin disposed in the second insertion hole; the upper end of the fourth link is provided with a second through hole, the end of the first crossbar passes through the second through hole, and the second pin is located in front of the fourth link.

10. The gripping robotic hand according to claim 2, characterized in that, Two counterweight limiting blocks are provided at the rear of the base, and each of the two counterweight limiting blocks has a threaded hole at its center. Two mounting holes are provided on the base, and a third bearing is provided in each of the two mounting holes. The back of the first transmission gear and the second transmission gear are provided with an integrally formed threaded post, which passes through the corresponding third bearing and is threadedly connected to the corresponding threaded hole.

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