Mechanical hand end effector

Abstract

This invention discloses a robotic end effector, specifically relating to the field of robotic arm technology. It includes a positioning rod fixedly connected to a frame, with a rotating positioning seat fixed to one end of the positioning rod. A connecting plate is rotatably connected to the middle of the side of the rotating positioning seat. The driving component of this invention drives the connecting plate to rotate according to the workpiece's position, moving the robotic finger to a suitable height and angle. The driving component extends from its initial retracted state. When the driving component extends to its maximum distance, a limiting pin abuts against the positioning surface of the connecting plate, limiting the orientation of the connecting plate and improving the repeatability of the end effector. Subsequently, a rotary cylinder actuates, rotating the gripping end of the robotic finger to a position corresponding to the workpiece. This allows the robotic finger to grasp and transfer workpieces in different directions, providing it with multi-directional orientation adjustment capabilities to adapt to workpiece grasping requirements with different arrangement orientations and placement postures, reducing the need for frequent adjustments to the robotic arm's movement trajectory.

Description

Technical Field

[0001] This invention relates to the field of robotic arm technology, specifically to a robotic arm end effector. Background Technology

[0002] With the development of industrial automation technology, robotic arms are widely used in operations such as parts handling, assembly, sorting, palletizing, and loading / unloading. The end effector, as the actuator that directly contacts the workpiece, is usually installed at the end of the robotic arm and, depending on the shape, size, and operational requirements of the workpiece, uses methods such as gripper clamping, vacuum adsorption, or magnetic adsorption to grasp and release the workpiece.

[0003] The robotic fingers in existing robotic arm end effectors are typically mounted in a fixed posture. When the workpiece's orientation, placement angle, or gripping position changes, the entire robotic arm needs to move, rotate, or re-plan its motion trajectory, which can easily result in a long robotic arm motion path, complex adjustment process, and low gripping efficiency. Furthermore, the end effector lacks a reliable endpoint positioning structure after reaching the working position, making it prone to posture deviations due to factors such as cylinder stroke errors and connection gaps, affecting the repeatability and positioning accuracy of the robotic fingers. Summary of the Invention

[0004] The purpose of this invention is to provide a robotic end effector to solve the problems mentioned in the background section.

[0005] The main technical problem solved by this invention is: When the robotic arm moves over a large range or replans its motion trajectory, it is easy to cause the robotic arm's motion path to be long and the grasping efficiency to be low. At the same time, the end effector is prone to posture deviation when it reaches the working position due to factors such as cylinder stroke error and connection gap, which affects the repeatability and positioning accuracy of the robotic finger.

[0006] This invention can be achieved through the following technical solutions: A robotic end effector includes a positioning rod fixedly connected to a frame, a rotating positioning seat fixed to one end of the positioning rod, a connecting plate rotatably connected to the middle of the side of the rotating positioning seat, a mounting block fixed to the upper end face of the connecting plate, and a driving component hinged to the other end of the positioning rod for driving the connecting plate to rotate around a rotation axis. The rotating positioning seat is internally fitted with a limiting component that restricts the rotation angle of the connecting plate. A limiting pin is installed at the center of the edge of the outer wall of the rotating positioning seat to restrict the initial position of the connecting plate. The limiting pin is perpendicular to the axis of the rotating positioning seat. A rotary cylinder is fixed to the lower end face of the connecting plate. The driving end of the rotary cylinder is connected to an outer mounting plate. The front end of the outer mounting plate is provided with a mechanical finger. The clamping end of the mechanical finger faces downward and rotates horizontally to clamp. The main shaft end of the rotary cylinder is not axially parallel to the length extension direction of the mechanical finger.

[0007] A further technical improvement of the present invention is that: the surface of the connecting plate is provided with a plurality of positioning holes arranged in a ring; The inner wall of the rotating positioning seat is provided with an annular groove, and a snap-fit ​​part that slides along the center of the rotating positioning seat is slidably installed inside the annular groove. The snap-fit ​​part is snap-fitted into the positioning hole.

[0008] A further technical improvement of the present invention is that: the snap-fit ​​part includes a limiting slip ring, and a plurality of positioning pins corresponding to the positioning holes are installed on the side surface of the limiting slip ring facing the connecting plate. A limiting cylinder is installed on the end surface of the positioning rod facing the rotating positioning seat, and the pushing end of the limiting cylinder is fixed to the other side of the limiting slip ring.

[0009] A further technical improvement of the present invention is that: the mechanical finger includes a rectangular support plate, and a finger assembly is mounted on the front end face of the support plate; The finger assembly includes a fixed block and a movable block arranged in pairs on the lower end face of the support plate. The two movable blocks are located between the two fixed blocks. The fixed blocks are fixedly connected to the bottom surface of the support plate. The rear ends of the two movable blocks are connected to the drive assembly inside the support plate. The front end of the fixed block is provided with a fitting opening, and the front end of the movable block forms a clamping opening for clamping the workpiece.

[0010] A further technical improvement of the present invention is that the driving assembly includes two telescopic cylinders distributed along the length of the support plate. The piston rods of the two telescopic cylinders are fixedly connected to the support plate, and the cylinder bodies of the two telescopic cylinders are fixedly connected to a connecting frame. The two connecting frames are rotatably connected to the support plate through rotating shafts on corresponding sides, and the front ends of the two rotating shafts are fixedly connected to the rear ends of the movable block, respectively.

[0011] A further technical improvement of the present invention is that the driving component includes a linear cylinder, and a U-shaped block is fixed to the front end of the piston rod of the linear cylinder, and the U-shaped block is hinged to the protruding end of the upper part of the mounting block.

[0012] Compared with the prior art, the present invention has the following beneficial effects: 1. The driving component drives the connecting plate to rotate according to the position of the workpiece, so that the robotic finger moves to a suitable height and angle. The driving component extends from the initial retracted state. When the driving component extends to the maximum distance, the limit pin abuts against the positioning surface of the connecting plate, which limits the posture of the connecting plate and improves the repeatability of the end effector. Then the rotary cylinder moves to rotate the gripping end of the robotic finger to the position corresponding to the workpiece, so that the robotic finger can complete the workpiece gripping and transfer in different directions. This gives the robotic finger the posture adjustment capability in multiple directions, which can adapt to the workpiece gripping requirements of different arrangement directions and different placement postures, and reduce the problem of frequent adjustment of the movement trajectory of the robotic arm. 2. By using a limit cylinder to drive several positioning pins to selectively insert into the positioning holes, the connecting plate can be mechanically locked at multiple set angles. This not only adjusts the working posture of the mechanical fingers and prevents the connecting plate from rotating on its own under the action of workpiece gravity or clamping reaction force, but also allows several positioning pins to engage with several positioning holes simultaneously, forming a multi-point circumferential restriction on the connecting plate. The limit cylinder and the driving component form a sequential control, ensuring that the connecting plate can only rotate after the positioning pins exit the positioning holes, and is relocked after the connecting plate rotates into place. Attached Figure Description

[0013] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0014] Figure 1 This is a schematic diagram of the external structure of the present invention; Figure 2 This is a three-dimensional structural schematic diagram of the present invention from another angle; Figure 3 This is a three-dimensional structural diagram of the mechanical finger of the present invention; Figure 4 This is a schematic diagram of the installation structure of the connecting plate and the rotating positioning seat of the present invention.

[0015] In the diagram: 1. Positioning rod; 2. Connecting plate; 3. Rotary cylinder; 4. External mounting plate; 5. Mechanical finger; 6. Limit pin; 7. Linear cylinder; 8. Fixed block; 9. Movable block; 10. Telescopic cylinder; 11. Positioning hole; 12. Limiting slip ring; 13. Positioning pin; 14. Rotating positioning seat; 15. Annular groove; 16. Mounting block. Detailed Implementation

[0016] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided.

[0017] Please see Figures 1-4As shown, the present invention provides a robotic end effector, including a positioning rod 1 fixedly connected to a frame, a rotating positioning seat 14 fixed to one end of the positioning rod 1, a connecting plate 2 rotatably connected to the middle of the side of the rotating positioning seat 14, and a driving component for driving the connecting plate 2 to rotate around the rotation axis at the other end of the positioning rod 1. The rotating positioning seat 14 has a limiting component that restricts the rotation angle of the connecting plate 2; A limiting pin 6 is installed at the center of the edge of the outer wall of the rotating positioning seat 14 to restrict the initial position of the connecting plate 2. The limiting pin 6 is perpendicular to the axis of the rotating positioning seat 14. A rotary cylinder 3 is fixed to the lower end face of the connecting plate 2. The drive end of the rotary cylinder 3 is connected to an outer mounting plate 4. The front end of the outer mounting plate 4 is provided with a mechanical finger 5. The clamping end of the mechanical finger 5 faces downward and rotates horizontally to clamp. The spindle end of the rotary cylinder 3 is not axially parallel to the length extension direction of the mechanical finger 5.

[0018] First, the positioning rod 1 is fixedly connected to the end of the robotic arm or the frame to achieve the installation and positioning between the end effector and the main body of the robotic arm. The connecting plate 2 is installed through the rotating connection structure in the middle of the side of the rotating positioning seat 14, so that the connecting plate 2 swings around the set rotation axis of the rotating positioning seat 14, thereby changing the spatial posture of the robotic finger 5 relative to the robotic arm.

[0019] When the working position of the mechanical finger 5 needs to be adjusted, the driving component moves. When the driving component extends and retracts, its output end pulls the connecting plate 2, causing the connecting plate 2 to rotate around the rotation axis of the rotating positioning seat 14. This converts the linear motion of the driving component into the angular swing of the connecting plate 2, so that the mechanical finger 5 installed on the connecting plate 2 and below it changes its angle synchronously, thereby realizing the adjustment of the overall posture of the mechanical finger 5.

[0020] During the rotation of the connecting plate 2, the driving component extends from its initial retracted state. When the driving component extends to its maximum distance, the limiting pin 6 abuts against the positioning surface of the connecting plate 2, thereby limiting the posture of the connecting plate 2 and ensuring that the mechanical finger 5 maintains a uniform initial position during operation, thus improving the repeatability of the end effector.

[0021] When the robotic finger 5 needs to adjust its gripping direction, the rotary cylinder 3 is activated. The rotary cylinder 3 causes its output spindle to rotate, which in turn drives the outer mounting plate 4 connected to its drive end to rotate synchronously. When the outer mounting plate 4 rotates, it can drive the robotic finger 5 to adjust its angle around the rotation axis of the rotary cylinder 3, enabling the robotic finger 5 to complete workpiece gripping and transfer in different directions and change its gripping posture in space. When the connecting plate 2 abuts against the limit pin 6, the gripping end of the robotic finger 5 faces downward and rotates horizontally to grip and grasp the workpiece. The vertical position of the robotic finger 5 is adjusted by the swing of the connecting plate 2, and the horizontal gripping direction is adjusted by the rotary cylinder 3, thereby expanding the working range of the robotic finger 5.

[0022] See Figure 1 and Figure 4 As shown, the surface of the connecting plate 2 is provided with a number of positioning holes 11 arranged in a ring. The inner wall of the rotating positioning seat 14 is provided with an annular groove 15. A snap-fit ​​part that slides along the center of the rotating positioning seat 14 is slidably installed inside the annular groove 15. The snap-fit ​​part is snap-fitted with the positioning hole 11. The locking part includes a limiting slip ring 12. Several positioning pins 13 that are locked to the positioning holes 11 are installed on the side surface of the limiting slip ring 12 facing the connecting plate 2. A limiting cylinder is installed on the end surface of the positioning rod 1 facing the rotating positioning seat 14. The pushing end of the limiting cylinder is fixed to the other side of the limiting slip ring 12.

[0023] When it is necessary to adjust the working angle of the connecting plate 2 and the mechanical finger 5, the limit cylinder retracts first, and the output end of the limit cylinder drives the limit slip ring 12 to slide away from the connecting plate 2 along the ring groove 15. At this time, the locking part does not lock with the positioning hole 11.

[0024] The driving component pushes the connecting plate 2 to rotate around the rotation axis of the rotating positioning seat 14. When the connecting plate 2 rotates, the rotary cylinder 3, the outer mounting plate 4 and the mechanical finger 5 installed below the connecting plate 2 swing synchronously with the connecting plate 2, so that the mechanical finger 5 is adjusted to the tilt angle or working posture corresponding to the workpiece to be gripped.

[0025] After the connecting plate 2 rotates to the preset angle, the driving component stops moving. At this time, the limiting cylinder extends and pushes the limiting slip ring 12 along the ring groove 15 and closer to the connecting plate 2, so that several positioning pins 13 are inserted into the corresponding positioning holes 11 at the same time. After the positioning pins 13 are engaged with the positioning holes 11, the positioning pins 13 can form a mechanical restriction on the connecting plate 2 in the circumferential direction, preventing the connecting plate 2 from continuing to rotate relative to the rotating positioning seat 14, thereby fixing the connecting plate 2 at the current working angle.

[0026] Several positioning holes 11 are arranged in a ring around the rotation axis of the connecting plate 2, so that the connecting plate 2 can be engaged with the corresponding positioning hole 11 by the positioning pin 13 after rotating to different set angles.

[0027] See Figure 4 As shown, the mechanical finger 5 includes a rectangular support plate, and a finger assembly is mounted on the front end face of the support plate; The finger assembly includes a fixed block 8 and a movable block 9 arranged in pairs on the lower end face of the support plate. The two movable blocks 9 are located between the two fixed blocks 8. The fixed blocks 8 are fixedly connected to the bottom surface of the support plate. The rear ends of the two movable blocks 9 are connected to the drive assembly inside the support plate. The front end of the fixed block 8 is provided with a fitting opening, and the front end of the movable block 9 forms a clamping opening for clamping the workpiece. The drive assembly includes two telescopic cylinders 10 distributed along the length of the support plate. The piston rods of the two telescopic cylinders 10 are fixedly connected to the support plate, and the cylinder bodies of the two telescopic cylinders 10 are fixedly connected to connecting frames. The two connecting frames are rotatably connected to the support plate through rotating shafts on corresponding sides. The front ends of the two rotating shafts are fixedly connected to the rear ends of the movable block 9, respectively.

[0028] After the end effector of the robot moves to the workpiece to be clamped, the part of the workpiece to be clamped enters between the fitting opening and the clamping opening; the two telescopic cylinders 10 can operate simultaneously, or they can operate separately depending on the number of workpieces and their location.

[0029] When clamping a workpiece, compressed air enters the corresponding air chamber of the telescopic cylinder 10. Since the piston rod end of the telescopic cylinder 10 is connected to the support plate, the position of the piston rod relative to the support plate is restricted. Therefore, after the cylinder is vented, the cylinder body moves relative to the piston rod.

[0030] like Figure 3 As shown, when the cylinder body of the telescopic cylinder 10 moves, it drives the connecting frame fixedly connected to it to move. The connecting frame is restricted by the rotation of the rotating shaft and cannot simply move in a straight line with the cylinder body. Therefore, the linear driving force generated by the telescopic cylinder 10 is converted into the rotational torque of the connecting frame around the rotating shaft, causing the connecting frame to drive the rotating shaft to rotate relative to the support plate. Since the front end of the rotating shaft is fixedly connected to the rear end of the movable block 9, when the rotating shaft rotates, the movable block 9 swings synchronously with the rotating shaft, so that the clamping port at the front end of the movable block 9 gradually approaches the contact port at the front end of the corresponding fixed block 8. When the movable block 9 rotates to the clamping position, one side of the workpiece contacts the contact port of the fixed block 8, and the other side of the workpiece contacts the clamping port of the movable block 9. The contact port and the clamping port together cover and press against both sides of the workpiece, thereby completing the clamping of the workpiece.

[0031] See Figure 2 As shown, a mounting block 16 is fixed to the upper end face of the connecting plate 2; The driving component includes a linear cylinder 7, with a U-shaped block fixed to the front end of the piston rod of the linear cylinder 7. The U-shaped block is hinged to the protruding end of the upper part of the mounting block 16.

[0032] When the connecting plate 2 needs to be adjusted in angle, the limiting cylinder first drives the limiting slip ring 12 to slide away from the connecting plate 2, so that the positioning pin 13 set on the limiting slip ring 12 exits the positioning hole 11 on the connecting plate 2, and releases the circumferential locking of the locking part to the connecting plate 2.

[0033] Subsequently, compressed air is introduced into the linear cylinder 7, and the piston rod extends or retracts relative to the cylinder body. When the piston rod of the linear cylinder 7 extends, the U-shaped block pushes the mounting block 16 to move in one direction, causing the connecting plate 2 to rotate around its rotation axis in the first direction. When the piston rod of the linear cylinder 7 retracts, the U-shaped block pulls the mounting block 16 to move in the opposite direction, causing the connecting plate 2 to rotate in the opposite direction.

[0034] In use, the end effector moves to the position of the workpiece to be grasped. The drive unit drives the connecting plate 2 to rotate according to the position of the workpiece, so that the mechanical finger 5 moves to a suitable height and angle. The drive unit extends from the initial retracted state. When the drive unit extends to the maximum distance, the limiting pin 6 abuts against the positioning surface of the connecting plate 2 to limit the posture of the connecting plate 2, thereby improving the repeatability of the end effector. Then, the rotary cylinder 3 is activated, so that the gripping end of the mechanical finger 5 rotates to the position corresponding to the workpiece, enabling the mechanical finger 5 to complete the workpiece grasping and transfer in different directions. This gives the mechanical finger 5 the posture adjustment capability in multiple directions, which can adapt to the workpiece grasping requirements of different arrangement directions and different placement postures, reducing the problem of frequent adjustment of the movement trajectory of the robot. By using a limit cylinder to drive several positioning pins 13 to selectively insert into positioning holes 11, the connecting plate 2 can be mechanically locked at multiple set angles. This not only adjusts the working posture of the mechanical finger 5 and prevents the connecting plate 2 from rotating on its own under the action of workpiece gravity or clamping reaction force, but also allows several positioning pins 13 to simultaneously engage with several positioning holes 11, forming a multi-point circumferential restriction on the connecting plate 2. The limit cylinder and the driving component form a sequential control, ensuring that the connecting plate 2 can only rotate after the positioning pins 13 exit the positioning holes 11, and is relocked after the connecting plate 2 has rotated into place.

[0035] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A robotic end effector, comprising a positioning rod (1) fixedly connected to a frame, characterized in that: One end of the positioning rod (1) is fixed with a rotating positioning seat (14), and a connecting plate (2) is rotatably connected to the middle of the side of the rotating positioning seat (14). The other end of the positioning rod (1) is hinged with a driving component for driving the connecting plate (2) to rotate around the rotation axis. The rotating positioning seat (14) is internally fitted with a limiting element that restricts the rotation angle of the connecting plate (2); A limiting pin (6) is installed at the middle of the edge of the outer wall of the rotating positioning seat (14) to limit the initial position of the connecting plate (2). The limiting pin (6) is perpendicular to the axis of the rotating positioning seat (14). A rotary cylinder (3) is fixed on the lower end face of the connecting plate (2). The driving end of the rotary cylinder (3) is connected to an outer mounting plate (4). The front end of the outer mounting plate (4) is provided with a mechanical finger (5). The clamping end of the mechanical finger (5) faces downward and rotates horizontally to clamp. The spindle end of the rotary cylinder (3) is not axially parallel to the length extension direction of the mechanical finger (5).

2. The robotic end effector according to claim 1, characterized in that, The surface of the connecting plate (2) is provided with a number of positioning holes (11) arranged in a ring. The inner wall of the rotating positioning seat (14) is provided with an annular groove (15), and a snap-fit ​​part that slides along the center of the rotating positioning seat (14) is slidably installed inside the annular groove (15). The snap-fit ​​part is snap-fitted with the positioning hole (11).

3. The robotic end effector according to claim 2, characterized in that, The snap-fit ​​part includes a limiting slip ring (12). The limiting slip ring (12) has several positioning pins (13) that are snap-fitted to the positioning holes (11) on one side surface facing the connecting plate (2). The positioning rod (1) has a limiting cylinder installed on one end surface facing the rotating positioning seat (14). The pushing end of the limiting cylinder is fixed to the other side of the limiting slip ring (12).

4. The robotic end effector according to claim 1, characterized in that, The mechanical finger (5) includes a rectangular support plate, and a finger assembly is mounted on the front end face of the support plate; The finger assembly includes a fixed block (8) and a movable block (9) arranged in pairs on the lower end face of the support plate. The two movable blocks (9) are located between the two fixed blocks (8). The fixed blocks (8) are fixedly connected to the bottom surface of the support plate. The rear ends of the two movable blocks (9) are connected to the drive assembly inside the support plate. The front end of the fixed block (8) is provided with a fitting opening. The front end of the movable block (9) forms a clamping opening for clamping the workpiece.

5. The robotic end effector according to claim 4, characterized in that, The drive assembly includes two telescopic cylinders (10) distributed along the length of the support plate. The piston rods of the two telescopic cylinders (10) are fixedly connected to the support plate, and the cylinder bodies of the two telescopic cylinders (10) are fixedly connected to the connecting frame. The two connecting frames are rotatably connected to the support plate through the rotating shafts on the corresponding sides. The front ends of the two rotating shafts are fixedly connected to the rear ends of the movable block (9).

6. The robotic end effector according to claim 1, characterized in that, A mounting block (16) is fixed on the upper end face of the connecting plate (2); The driving component includes a linear cylinder (7), and a U-shaped block is fixed to the front end of the piston rod of the linear cylinder (7). The U-shaped block is hinged to the protruding end of the upper part of the mounting block (16).

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