A robotic arm suitable for batch gripping and single-sheet separation of sheet metal

Abstract

This application relates to the field of sheet metal gripping technology, and discloses a robotic arm suitable for batch gripping and single-sheet separation of sheets metal. The arm includes: a main support spanning across the sheet metal storage area and above the laser cutting machine worktable; a main frame slidably connected laterally within the transverse guide rail of the main support, reciprocating between the sheet metal storage area and the laser cutting machine worktable along a first horizontal direction; and a gripping frame assembly installed at the bottom of the main frame, including gripping frames A and B that can move relative to each other along a second horizontal direction. By integrating the gripping frame assembly and the suction cup assembly at the bottom of the same main frame, integrated continuous operation of batch gripping and single-sheet separation is achieved. The gripping frame transports an entire stack of sheets at once using a forklift-style bottom support method, while the suction cup assembly adsorbs and separates sheets one by one at the separation station and loads them, simplifying the production line layout.

Description

Technical Field

[0001] This invention relates to the field of sheet material gripping technology, specifically a robotic arm suitable for batch gripping and single-sheet separation of sheet materials. Background Technology

[0002] Before laser cutting, stacked sheets need to be separated and transported to the cutting table one by one. Currently, the sheet loading process typically involves manual handling with auxiliary lifting devices, or a single-function suction cup robotic arm for individual sheet grabbing. For the transfer of batches of sheets, forklifts or specialized lifting vehicles are usually required to transport the entire stack to the loading station, where suction cup robotic arms then separate each sheet individually. These two processes require separate equipment, occupying a significant amount of space, and the connection between processes requires manual intervention, resulting in low automation and difficulty in further improving production efficiency.

[0003] Existing suction cup-type sheet material feeding devices mostly use vacuum suction cups to directly adsorb the top layer of sheet material, separating it from the lower layers through lifting motion. However, when there is an oil film, moisture, or electrostatic adsorption on the sheet material surface, adjacent sheets are prone to sticking together, causing multiple sheets to be lifted simultaneously, affecting the normal progress of subsequent cutting and processing. To solve the adhesion problem, some equipment has added air-blowing separation devices or mechanical shaking devices, but the direction and position of air blowing are limited by the independently arranged pipeline structure, resulting in limited penetration into the gaps between the bottom layers of the sheet material; the shaking separation structure is prone to damaging the seal between the suction cup and the sheet material during vibration, leading to a decrease in adsorption force or even sheet material detachment. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a robotic arm suitable for batch gripping and single-sheet separation of sheet materials, solving the problems of existing sheet material feeding equipment requiring separate devices for batch handling and single-sheet separation, and poor reliability in separating adhered sheet materials.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a robotic arm suitable for batch gripping and single-sheet separation of sheet metal, comprising:

[0006] The main support spans across the plate storage area and above the laser cutting machine worktable;

[0007] The main frame of the equipment is slidably connected to the transverse guide rail of the main support, and moves back and forth between the plate storage area and the laser cutting machine worktable along the first horizontal direction;

[0008] The gripping frame assembly is installed at the bottom of the main frame of the equipment and includes gripping frame A and gripping frame B that can move relative to each other in a second horizontal direction. The lower ends of gripping frame A and gripping frame B are respectively provided with a plurality of gripping rods extending in the first horizontal direction. The gripping rods are used to support the plates from the bottom of the plate assembly.

[0009] The suction cup assembly is installed at the bottom of the main frame of the device and is located above the gripping rod in the vertical direction. The suction cup assembly includes a suction cup bracket that can be raised and lowered in the vertical direction, a plurality of suction cup components installed below the suction cup bracket, and an elastic buffer connecting the suction cup bracket and the suction cup components.

[0010] The suction cup bracket has an edge positioning push plate assembly installed around its bottom perimeter. The edge positioning push plate assembly includes an L-shaped reference block, a miniature pushing cylinder, and a magnetorheological fluid damper connected in series between the miniature pushing cylinder and the L-shaped reference block. The magnetorheological fluid damper is filled with magnetorheological fluid, and its cylinder sidewall is embedded with a ring-shaped excitation coil. A visual positioning camera is installed at the center of the suction cup bracket. A position fine adjustment rotating disk and a coaxially arranged disc magnetorheological fluid brake are installed at the connection between the suction cup bracket and the main frame of the equipment. The position fine adjustment rotating disk is driven by a stepper motor and a harmonic reducer to drive the suction cup bracket to rotate around the vertical axis for angle correction. The rotor of the disc magnetorheological fluid brake is fixedly connected to the rotating surface of the rotating disk, and the stator is fixedly connected to the fixed surface of the rotating disk. An excitation coil is provided inside the stator.

[0011] A vibration mechanism is installed on one side of the outer surface of the suction cup bracket and is used to drive the suction cup bracket to vibrate.

[0012] A vacuum system, connected to the suction cup assembly, provides suction force.

[0013] Preferably, the main frame of the device is slidably connected to the main support via a guide rail pair and is driven by a first drive mechanism to move in the first horizontal direction; the main frame of the device is provided with a vertical lifting drive device to drive the suction cup assembly to lift synchronously as a whole.

[0014] Preferably, the A gripper and the B gripper are connected by a bidirectional screw mechanism and driven by a second drive mechanism to move symmetrically closer or further apart; the front end of the gripper rod is provided with an inlet ramp, and the surface of the gripper rod is provided with an anti-slip coating.

[0015] Preferably, the suction cup assembly includes a connecting rod and a suction cup body. The upper end of the connecting rod is movably inserted through the suction cup bracket. The elastic buffer is a compression spring sleeved on the outer periphery of the connecting rod. The two ends of the compression spring abut against the suction cup bracket and the limiting part at the lower end of the connecting rod, respectively.

[0016] Preferably, the vibration mechanism includes a reciprocating cylinder assembly, which drives the suction cup bracket to generate vertical vibration with a frequency of 10 to 20 Hz and an amplitude of 1 to 3 mm when the vibration mechanism is activated.

[0017] Preferably, the gripping rod has an internal air passage, and the upper surface of the end of the gripping rod away from the center of the main frame of the equipment has an air hole that communicates with the air passage. A compressed air source is provided on one side of the outer wall of the main support. The air passage is connected to the compressed air source through a pipeline and is controlled to open and close. The air outlet direction of the air hole points to the interlayer gap at the bottom edge of the plate assembly.

[0018] Preferably, a pre-pressure roller frame is also installed on the front side of the main frame of the equipment along the first horizontal direction. The outer surface of the pre-pressure roller frame is provided with several freely rotatable elastic rubber-coated rollers. The pre-pressure roller frame is floatingly connected to the main frame of the equipment through an elastic guide structure, so that the lowest point of the elastic rubber-coated rollers is lower than the height of the initial contact plane of the suction cup assembly when in operation.

[0019] Preferably, at least one of the elastic rubber-coated rollers is provided with a rotary encoder or vibration sensor at its shaft to detect the jumping signal generated by the elastic rubber-coated roller due to the unevenness of the plate surface.

[0020] Preferably, it also includes a displacement detection device, which is installed on one side of the outer wall of the main frame of the equipment, and the second drive mechanism automatically adjusts the distance between the A gripper and the B gripper according to the preset plate width value.

[0021] Preferably, the suction cup assembly includes multiple suction cup components arranged in an array, and the vacuum system is connected to each suction cup component through a multi-channel gas distribution block and several independently controlled solenoid valves; the main frame of the device is also equipped with a photoelectric sensor array for scanning the contour of the upper surface of the board assembly before adsorption, and the solenoid valves, based on the feedback from the photoelectric sensor array, only supply vacuum to the suction cup components located above the solid area of ​​the board.

[0022] Working Principle: The robotic arm for batch gripping and single-sheet separation of sheet metal proposed in this invention is supported and driven by an external three-axis gantry-type mobile platform. Using a gantry truss as a carrier, the robotic arm for batch gripping and single-sheet separation of sheet metal is mounted on the gantry truss. The three-axis movement function of the three-axis gantry-type mobile platform enables the movement and height adjustment of the robotic arm. Under the support and movement of the three-axis gantry-type mobile platform, the main frame of the equipment slides to the sheet metal storage area, descends to allow the gripping rod to insert into the bottom gap of the sheet metal stack and support the entire stack of sheets, and then is lifted and transferred to the separation station and lowered onto a temporary support surface. The two gripping frames... Symmetrical unfolding allows the gripping rod to retract laterally, completing the support conversion; subsequently, the pre-pressure roller frame contacts the upper surface of the board to pre-press and flatten it and detect warping; the suction cup assembly descends to adhere to the top layer of board; the shaking mechanism drives the suction cup to vibrate at high frequency while air is sprayed into the bottom interlayer through the air hole at the end of the gripping rod, forming a double separation of upper shaking and lower blowing, causing the single board to separate from the lower layer; after the suction cup lifts the separated single board, the main frame of the equipment slides to the laser cutting machine worktable to release the board, and then returns to repeat the separation action until the entire stack is completed; when changing specifications, the displacement detection device provides feedback on the position and automatically adjusts the spacing of the gripping frame.

[0023] This invention provides a robotic arm suitable for batch gripping and single-sheet separation of sheet metal. It has the following beneficial effects:

[0024] 1. This invention integrates the gripping frame assembly and the suction cup assembly at the bottom of the same main frame of the equipment, realizing integrated continuous operation of batch forklift picking and single sheet separation. The gripping frame transports the entire stack of sheets at once using a forklift-style bottom support method, while the suction cup assembly picks up and separates sheets one by one at the separation station and loads them. The two functional mechanisms share a single walking and lifting system, reducing the equipment's footprint, simplifying the production line layout, and significantly improving the sheet loading efficiency.

[0025] 2. This invention employs a composite separation structure combining a spring-loaded floating suction cup with a shaking mechanism and an air jet from the end of the gripping rod, forming a dual separation mechanism of upper shaking and lower blowing. The shaking mechanism drives the suction cup to vibrate at high frequency, applying alternating forces to the sheet material through the extension and contraction of the compressed spring. Simultaneously, the air jet at the end of the gripping rod sprays airflow into the interlayer gaps at the bottom of the sheet material, creating an air knife effect. This effectively overcomes vacuum adsorption, oil film adhesion, and electrostatic adsorption between sheets, ensuring reliable single-sheet separation. It is particularly suitable for thin stainless steel sheets or coated sheets with severe surface adhesion.

[0026] 3. By setting a pre-pressure roller frame on the front side of the main frame of the equipment, the present invention can not only pre-press and flatten the end of the plate to facilitate the adhesion and adsorption of the suction cup, but also detect the flatness of the plate online through the roller jump signal, and reject the plate that exceeds the standard in advance, so as to avoid unqualified plates entering the laser cutting process and causing poor processing quality or equipment collision accidents. This invention gives the equipment a quality inspection function, improves the intelligence level of the equipment and production safety.

[0027] 4. This invention utilizes a series design of a magnetorheological fluid damper and an edge positioning push plate assembly. This allows the contact force of the push plate during the translation and centering of the sheet material to be adjusted in real time via the excitation coil current. The millisecond-level response of the flexible damping achieves zero-impact pushing, completely avoiding scratches or indentations on the edge of the sheet material. At the same time, the disc-type magnetorheological fluid brake instantly solidifies and locks the angle of the rotating disc after the calibration is completed. It clamps tightly when the power is off and does not require continuous power supply to maintain torque, ensuring that the sheet material does not drift during high-speed transportation and placement. This achieves a high-precision, non-destructive posture calibration and stable locking effect for the sheet material before laser cutting. Attached Figure Description

[0028] Figure 1 This is a perspective view of the robotic arm used for batch gripping and single-sheet separation of sheet metal in this invention.

[0029] Figure 2 This is a diagram illustrating the robotic arm used for batch gripping and single-sheet separation of sheet metal in this invention.

[0030] Figure 3 For the present invention Figure 2 Enlarged view of point A in the image;

[0031] Figure 4 This is a schematic diagram of the robotic arm for batch gripping and single-sheet separation of sheet metal in this invention;

[0032] Figure 5 This is a schematic diagram of the vacuum system in this invention;

[0033] Figure 6 This is a diagram illustrating the gripping frame assembly of the present invention;

[0034] Figure 7 This is a schematic diagram of the shaking mechanism in this invention;

[0035] Figure 8 This is a cross-sectional view of the elastic buffer element in this invention;

[0036] Figure 9 This is a cross-sectional view of the vacuum system in this invention;

[0037] Figure 10 This is a diagram illustrating the edge positioning push plate assembly in this invention.

[0038] The components include: 1. Main support; 2. Main frame of the equipment; 3. Gripping frame assembly; 31. A gripping frame; 32. B gripping frame; 33. Gripping rod; 331. Guide slope; 332. Anti-slip coating layer; 333. Air passage; 334. Air hole; 34. Bidirectional screw mechanism; 4. Suction cup assembly; 41. Suction cup bracket; 42. Suction cup assembly; 421. Connecting rod; 422. Suction cup body; 423. Limiting part; 43. Elastic buffer; 5. Vibration mechanism; 51. Reciprocating cylinder assembly; 6. Vacuum system; 61. Multi-channel air distribution block; 62. Solenoid valve; 7. First drive mechanism; 8. Vertical lifting drive device; 9. Second drive mechanism; 10. Compressed air source; 11. Preload roller frame; 111. Elastic rubber-coated roller; 112. Elastic guide structure; 113. Rotary encoder; 12. Displacement detection device; 13. Photoelectric sensor array; 14. Edge positioning push plate assembly; 141. L-shaped reference block; 142. Miniature push cylinder; 143. Magnetorheological fluid damper; 15. Visual positioning camera; 16. Posture fine-tuning rotary disk; 17. Disc-type magnetorheological fluid brake. Detailed Implementation

[0039] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] Please see the appendix Figure 1 - Appendix Figure 10 This invention provides a robotic arm suitable for batch gripping and single-sheet separation of sheet metal, comprising:

[0041] Main support 1 spans across the plate storage area and above the laser cutting machine worktable;

[0042] The main frame 2 of the equipment is slidably connected to the transverse guide rail of the main support 1 and moves back and forth between the plate storage area and the laser cutting machine worktable along the first horizontal direction.

[0043] The gripping frame assembly 3 is installed at the bottom of the main frame 2 of the equipment and includes gripping frame A 31 and gripping frame B 32 that can move relative to each other in the second horizontal direction. The lower ends of gripping frame A 31 and gripping frame B 32 each have a plurality of gripping rods 33 extending in the first horizontal direction. The gripping rods 33 are used to support the plates from the bottom of the plate assembly.

[0044] The suction cup assembly 4 is installed at the bottom of the main frame 2 of the equipment and is located above the gripping rod 33 in the vertical direction. The suction cup assembly 4 includes a suction cup bracket 41 that can be raised and lowered in the vertical direction, a plurality of suction cup components 42 installed below the suction cup bracket 41, and an elastic buffer 43 connecting the suction cup bracket 41 and the suction cup components 42.

[0045] The vibration mechanism 5 is installed on one side of the outer surface of the suction cup bracket 41 and is used to drive the suction cup bracket 41 to vibrate.

[0046] Vacuum system 6 is connected to suction cup assembly 42 to provide suction force.

[0047] The main frame 2 of the equipment is slidably connected to the main support 1 through the guide rail pair, and is driven by the first drive mechanism 7 to move in the first horizontal direction; the main frame 2 of the equipment is equipped with a vertical lifting drive device 8, which is used to drive the suction cup assembly 4 to lift synchronously as a whole.

[0048] A gripper 31 and B gripper 32 are connected by a bidirectional screw mechanism 34 and driven by a second drive mechanism 9 to move symmetrically closer or further apart;

[0049] The bidirectional lead screw mechanism 34 engages with two nut seats via left and right helical thread sections, driving the A gripper frame 31 and the B gripper frame 32 to open and close symmetrically. The displacement detection device 12 provides real-time position feedback to automatically adjust the gripping spacing. The gripping rod 33 has an inlet ramp 331 at its front end to facilitate wedging into the bottom gap of the plate. The rod body is wrapped with a polyurethane anti-slip layer to prevent the plate from slipping during transport. The inlet ramp 331 at the front end of the gripping rod 33 acts as a guide when forking the plate assembly, allowing the gripping rod 33 to smoothly wed into the bottom gap of the plate and avoid hard collisions with the edge of the plate. The anti-slip coating 332 is made of polyurethane, which has a high surface friction coefficient. During the horizontal transport process when the gripping rod 33 supports the plate assembly, it effectively suppresses the sliding displacement of the plate caused by inertia or vibration, ensuring safe transport.

[0050] Specifically, the main frame 2 of the equipment serves as the motion support platform for the entire machine. Its horizontal sliding motion along the transverse guide rail of the main support 1 and the lifting motion of the vertical lifting drive device 8 work together to form a transport path in a two-dimensional plane. The gantry-type main support and the transverse lifting structure of the main frame of the equipment have been applied in the field of automatic sheet material feeding. The gripping frame assembly 3 and the suction cup assembly 4 are integrated at the bottom of the same main frame 2 of the equipment, and serve both batch forklifting and single sheet separation processes through a set of walking and lifting systems. The first driving mechanism 7 drives the main frame 2 of the equipment to slide on the main support 1. The gripping frame assembly 3 and the suction cup assembly 4 grip and adsorb the plates respectively. The robot for batch gripping and single separation of plates proposed in this embodiment is driven by an external displacement structure. The displacement structure has the ability to move in the horizontal and vertical directions, such as a three-axis gantry mobile platform. The robot for batch gripping and single separation of plates is installed on the Z-axis lifting end of the gantry gantry. The gantry gantry realizes the switching of the robot's planar position in the plate storage area, the separation station and the laser cutting machine worktable through the horizontal bidirectional tracks of the X-axis and Y-axis. The Z-axis lifting mechanism drives the robot to move synchronously to approach or detach from the plates. Thus, the three-axis gantry realizes the robot's movement and height adjustment at any point in three-dimensional space, and realizes the horizontal transfer of plates between the storage area, the separation station and the laser cutting machine worktable.

[0051] The vertical lifting drive device 8 lowers the gripping frame assembly 3 to the bottom gap height of the board during material picking, raises the board assembly to a safe height during transfer, places the board assembly on a temporary support surface at the separation station, and controls the lowering and raising height of the suction cup assembly 4 when feeding a single sheet.

[0052] The suction cup assembly 42 includes a connecting rod 421 and a suction cup body 422. The upper end of the connecting rod 421 is movably inserted through the suction cup bracket 41. The elastic buffer 43 is a compression spring sleeved on the outer periphery of the connecting rod 421. The two ends of the compression spring abut against the suction cup bracket 41 and the limiting part 423 at the lower end of the connecting rod 421, respectively.

[0053] Specifically, when the suction cup assembly 4 descends to contact the plate, the compression spring is compressed first, causing the suction cup body 422 to adhere to the plate surface with a certain pre-pressure, compensating for minor unevenness on the plate surface and establishing an initial seal. When the vacuum system 6 is activated, a negative pressure is formed inside the suction cup body 422, and atmospheric pressure tightly presses the suction cup body 422 against the plate, completing the adsorption action. The elastic buffer 43 not only plays a buffering role but also works in conjunction with the vibration mechanism 5 during the vibration separation process—the connecting rod 421 moves slightly axially under the vibration of the suction cup bracket 41, and the compression spring stretches and deforms accordingly. In addition, the connecting rod 421 is internally machined into a coaxial nested double-layer airflow channel. The upper end of the outer channel is connected to the vacuum branch of the module's air outlet for vacuum adsorption; the upper end of the inner channel is connected to the compressed air source 10 through an independent interface for positive pressure release. A rotary air connector is provided at the connection between the upper end of the connecting rod 421 and the module's air outlet, so that the connecting rod 421 can maintain the sealed connection of the double channels when vibrating with the suction cup bracket 41. The lower end of the connecting rod 421 is connected to the suction cup body 422. The suction cup body 422 has two independent airflow openings, which correspond to the vacuum adsorption channel and the positive pressure release channel, respectively. While maintaining the adsorption seal, the suction cup body 422 applies alternating tensile and compressive forces to the board, causing interlayer air to enter and destroy the adsorption force, thereby achieving single-sheet separation.

[0054] The multi-component regional control works as follows: Before adsorption, the photoelectric sensor array 13 performs a rapid optical scan on the upper surface of the board assembly to obtain the outline shape and hole location information of the board and transmits it to the control system; the control system determines whether the area below each suction cup assembly 42 is a solid board according to a preset algorithm. For suction cup assemblies 42 located on the outer edge of the board or directly opposite the pre-made holes, the control system instructs the corresponding solenoid valve 62 to remain closed and not to introduce vacuum into them; only the solenoid valve 62 connected to the suction cup assembly 42 corresponding to the solid board area is opened, and the vacuum is distributed to that part of the suction cup assembly 42 through the multi-way gas distribution block 61.

[0055] The multi-channel gas distribution block 61 is a metal gas distribution valve body with one air inlet and multiple air outlets. It is composed of several standard modular units spliced ​​along a rectangular array, with adjacent modules fastened together by snap-fit, and the mating surfaces are equipped with sealing rings. Each modular unit corresponds to a set of suction cup assemblies 42 and a solenoid valve 62. The first module has a main air inlet, which is connected to the vacuum pump outlet through a main pipeline; the last module is sealed with a blind flange. The number of modules can be flexibly increased or decreased according to the number of suction cup assemblies 4. If a single module fails, it can be replaced independently without affecting the normal operation of the remaining modules. Its air inlet is connected to the vacuum pump outlet of the vacuum system 6 through a main pipeline, and each air outlet is connected to the corresponding solenoid valve 62 and suction cup assembly 42 through an independent branch pipeline. The multi-channel gas distribution block 61 has a main air chamber inside, and each air outlet has an independent airflow channel between the main air chamber and each air outlet. The cross-sectional dimensions of each airflow channel are the same to ensure that each air outlet receives a balanced air pressure distribution.

[0056] The airflow channel between the main air chamber and the air outlet within each module unit adopts an equal path length design, meaning the airflow path length from the main air inlet to the air outlet of each module is equal. Specifically, the main air chamber runs through all modules along the module splicing direction to form a common air channel. The air outlet branches of each module are led out of the main air chamber with the same bending radius and arc length, and the number of bends is consistent. This design ensures that the airflow resistance along each branch is the same, and that each air outlet receives a balanced air pressure distribution, fundamentally eliminating uneven vacuum caused by differences in channel length.

[0057] During the multi-component regional control operation, when some solenoid valves 62 are closed, no airflow passes through the corresponding outlet and branch pipe. The airflow drawn by the vacuum pump flows only through the main air chamber to the branch where the solenoid valve 62 is open. Each open branch obtains a stable and consistent negative pressure value due to the balanced distribution characteristics of the gas distribution block, avoiding the decrease in system vacuum caused by some suction cups being empty, thereby ensuring that the adsorption force of the effective suction cup group is uniform and reliable.

[0058] The vibration mechanism 5 includes a reciprocating cylinder assembly 51. When the vibration mechanism 5 is started, it drives the suction cup bracket 41 to generate vertical vibration with a frequency of 10 to 20 Hz and an amplitude of 1 to 3 mm.

[0059] It also includes a displacement detection device 12, which is a wire-type displacement sensor whose movable end is connected to either gripping frame A 31 or gripping frame B 32. When the second drive mechanism 9 drives the bidirectional lead screw mechanism 34 to rotate to adjust the gripping frame opening, the displacement detection device 12 measures the displacement of the gripping frame in real time and feeds back the position signal to the control system. The control system compares the real-time position with the target opening corresponding to the preset plate width value, and adjusts the output speed and direction of the second drive mechanism 9 through a closed-loop control algorithm. The displacement detection device 12 measures the actual opening position of the gripping frame in real time and feeds it back to the control system. The control system compares the actual value with the target opening corresponding to the preset plate width, and adjusts the speed and direction of the second drive mechanism 9 according to the deviation through a closed-loop control algorithm until the gripping frame spacing accurately reaches the preset value and is locked.

[0060] Specifically, the reciprocating cylinder assembly 51 consists of a cylinder body, a piston rod, and a reversing control valve. Compressed air drives the piston rod to reciprocate rapidly. The output end of the piston rod is connected to the suction cup bracket 41. The reversing control valve alternately switches the air supply direction at a set frequency, causing the piston rod to drive the suction cup bracket 41 to generate high-frequency, small-amplitude vibrations. This effectively disrupts the vacuum adsorption effect and oil film tension between the plates. Simultaneously, controlling the amplitude within a small range avoids damaging the seal between the suction cup body 422 and the plate, ensuring that the adsorption force is not lost.

[0061] The gripping rod 33 has an internal air passage 333. An air hole 334, communicating with the air passage 333, is located on the upper surface of the end of the gripping rod 33 furthest from the center of the main frame 2. The air passage 333 is connected to a compressed air source 10 via a pipe and its operation is controlled. The air outlet of the air hole 334 points towards the interlayer gap at the bottom edge of the sheet material assembly. This application integrates the air hole 334 into the end of the gripping rod 33. When the gripping frame is deployed, the air hole 334 is precisely aligned with the interlayer gap at the bottom of the sheet material, eliminating the need for a separate air blowing pipe or air knife device.

[0062] In the single-sheet separation process, when the suction cup assembly 4 adsorbs the uppermost sheet material and initiates a shaking action, the control system issues a command to open the solenoid valve 62 connected to the air passage 333. Compressed air output from the compressed air source 10 enters the air passage 333 inside the gripping rod 33 through the pipeline and is ejected at high speed from the air hole 334 on the upper surface of the end. The airflow actively wedges into the bottom of the sheet material and expands the interlayer gap. This airflow-assisted separation action, together with the shaking lifting action of the upper suction cup assembly 42, forms a dual separation mechanism with upper and lower coordination—the airflow breaks the adsorption and adhesion at the bottom of the sheet material, and the shaking breaks the adsorption and adhesion at the top of the sheet material. The combined effect of these two actions improves the success rate of single-sheet separation.

[0063] A pre-pressure roller frame 11 is also installed on the front side of the main frame 2 along the first horizontal direction. The pre-pressure roller frame 11 contacts the upper surface of the plate before the suction cup assembly 4 descends and contacts the plate. The elastic guide structure 112 consists of a guide rod and a pre-pressure spring. The upper end of the guide rod is fixed to the main frame 2, and the lower end is slidably connected to the pre-pressure roller frame 11. The pre-pressure spring is sleeved on the outer periphery of the guide rod, and its two ends abut against the main frame 2 and the pre-pressure roller frame 11, respectively. When the main frame 2 continues to descend or moves slightly along the first horizontal direction, the pre-pressure roller frame 11 can adapt to the height change of the plate within a certain range under the action of the elastic guide structure 112. The elastic rubber-coated roller 111 rolls on the plate surface and applies a certain pre-pressure. This pre-pressure can flatten the slight warping or wave deformation at the end of the plate, so that the plate surface is restored to a flat state, creating good contact conditions for the subsequent adhesion and adsorption of the suction cup body 422. The rubber coating layer of the elastic rubber-coated roller 111 has elastic deformation capability and will not cause scratches on the plate surface.

[0064] During the rolling process, if there are significant unevenness defects on the surface of the sheet material, the elastic rubber-coated roller 111 will generate vertical jumping displacement. The rotary encoder 113 installed on the rotating shaft can sensitively capture this jumping signal and transmit the signal to the control system. The control system analyzes the amplitude and frequency of the jumping signal. When the jumping amount exceeds the preset threshold, the system determines that the sheet material has serious deformation that affects the subsequent processing quality, and then issues an alarm or suspends the operation of the equipment. The alarm terminal includes an audible and visual alarm and a human-machine interface. The audible and visual alarm is installed in a conspicuous position on the main frame 2 of the equipment. When the control system issues an alarm command, the audible and visual alarm emits a flashing red light accompanied by a buzzer sound to alert the operator. The human-machine interface simultaneously pops up a fault prompt window, displaying the alarm type, the detected value of the sheet material deformation exceeding the limit, and suggested handling measures.

[0065] The bottom of the suction cup bracket 41 is equipped with an edge positioning push plate assembly 14. The edge positioning push plate assembly 14 consists of an L-shaped reference block 141, a miniature push cylinder 142, and a magnetorheological fluid damper 143 connected in series between the two. The magnetorheological fluid damper 143 is filled with magnetorheological fluid and has an annular excitation coil embedded in its cylinder side wall. A visual positioning camera 15 is installed at the center of the suction cup bracket 41. A position fine adjustment rotating disk 16 and a coaxially arranged disc magnetorheological fluid brake 17 are installed at the connection between the suction cup bracket 41 and the main frame 2 of the equipment. The position fine adjustment rotating disk 16 is driven by a stepper motor and a harmonic reducer. The rotor of the disc magnetorheological fluid brake 17 is fixedly connected to the rotating surface of the rotating disk, and the stator is fixedly connected to the fixed surface of the rotating disk. An excitation coil is provided inside the stator. During operation, after the suction cup assembly 4 lifts a single sheet of material to the transfer height, the visual positioning camera 15 captures images of the four edges of the sheet. The image processing module of the control system calculates the horizontal offset of the center point of the sheet relative to the center of the suction cup bracket 41 and the deflection angle of the sheet edge relative to the first horizontal direction using an edge recognition algorithm. Subsequently, the control system extends the miniature push cylinder 142 in the direction corresponding to the offset command, and simultaneously applies a preset current to the annular excitation coil of the magnetorheological fluid damper 143. Under the action of the magnetic field, the apparent viscosity of the magnetorheological fluid increases, causing the L-shaped reference block 141 to contact and push the edge of the sheet in a flexible and controllable manner under the combined action of the cylinder thrust and the damper buffer. The opposite push plate moves synchronously to push the center of the sheet to coincide with the center of the suction cup bracket 41. The contact force is controlled in real time by adjusting the coil current to avoid damaging the sheet. On the surface, after centering is completed, the excitation coil is de-energized, the damping force is reduced to the minimum, and all push plates retract. Then, the control system commands the stepper motor of the position fine adjustment rotary disk 16 to rotate according to the deflection angle value. The stepper motor drives the suction cup bracket 41 to rotate around the vertical axis to correct the angle via the harmonic reducer. After correction, the excitation coil of the disc magnetorheological fluid brake 17 is energized. The magnetorheological fluid solidifies instantaneously in the shear gap between the rotor and the stator, generating braking torque to lock the angle of the suction cup bracket 41 along with the plate. There is no need for the stepper motor to continuously output holding torque. After correction and locking, the control system can perform secondary image acquisition to verify that the offset and deflection angle are within the allowable tolerance range. Subsequently, the main frame 2 of the equipment carries the plate with standardized posture to continue to be transferred to the laser cutting machine worktable and placed accurately. After placement, the brake is de-energized and the locking is released, and the device returns to the initial state.

[0066] The power circuit breaking system includes a contactor connected in series in the main power supply circuit of the equipment. The control coil of the contactor is connected to one digital output port of the control system. When the control system determines that the deformation of the plate exceeds the limit and the equipment needs to be stopped, the control system outputs a signal to de-energize the contactor coil, the main contacts of the contactor open, and the power supply to the vertical lifting drive device 8, the first drive mechanism, and the second drive mechanism 9 is cut off. All moving parts of the equipment immediately stop moving, ensuring that the equipment cannot continue to operate before the fault is cleared, thus ensuring operational safety.

[0067] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A robotic arm suitable for batch gripping and single-sheet separation of sheet metal, characterized in that, include: The main support (1) spans across the plate storage area and above the laser cutting machine worktable; The main frame (2) of the equipment is slidably connected to the transverse guide rail of the main support (1) and moves back and forth between the plate storage area and the laser cutting machine worktable along the first horizontal direction; The gripping frame assembly (3) is installed at the bottom of the main frame (2) of the equipment and includes an A gripping frame (31) and a B gripping frame (32) that can move relative to each other in the second horizontal direction. The lower ends of the A gripping frame (31) and the B gripping frame (32) respectively have a plurality of gripping rods (33) extending in the first horizontal direction. The gripping rods (33) are used to support the plates from the bottom of the plate assembly. The suction cup assembly (4) is installed at the bottom of the main frame (2) of the device and is located above the gripping rod (33) in the vertical direction. The suction cup assembly (4) includes a suction cup bracket (41) that can be raised and lowered in the vertical direction, a plurality of suction cup components (42) installed below the suction cup bracket (41), and an elastic buffer (43) connecting the suction cup bracket (41) and the suction cup components (42). The suction cup bracket (41) is equipped with an edge positioning push plate assembly (14) around its bottom perimeter. The edge positioning push plate assembly (14) includes an L-shaped reference block (141), a miniature push cylinder (142), and a magnetorheological fluid damper (143) connected in series between the miniature push cylinder (142) and the L-shaped reference block (141). The magnetorheological fluid damper (143) is filled with magnetorheological fluid and has an annular excitation coil embedded in its cylinder sidewall. A viewing device is installed at the center of the suction cup bracket (41). The sensory positioning camera (15) is connected to the suction cup bracket (41) and the main frame (2) of the device, and a position fine adjustment rotating disk (16) and a coaxially arranged disc magnetorheological fluid brake (17) are installed at the connection. The position fine adjustment rotating disk (16) is driven by a stepper motor and a harmonic reducer to drive the suction cup bracket (41) to rotate around the vertical axis to correct the angle. The rotor of the disc magnetorheological fluid brake (17) is fixedly connected to the rotating surface of the rotating disk, and the stator is fixedly connected to the fixed surface of the rotating disk. The stator is provided with an excitation coil. A vibration mechanism (5) is installed on one side of the outer surface of the suction cup bracket (41) and is used to drive the suction cup bracket (41) to vibrate. A vacuum system (6) is connected to the suction cup assembly (42) to provide adsorption force.

2. The robotic arm for batch gripping and single-sheet separation of sheet metal according to claim 1, characterized in that, The main frame (2) of the equipment is slidably connected to the main support (1) through the guide rail pair, and is driven by the first drive mechanism (7) to realize the movement in the first horizontal direction; the main frame (2) of the equipment is provided with a vertical lifting drive device (8) to drive the suction cup assembly (4) to lift synchronously as a whole.

3. The robotic arm according to claim 1, suitable for batch gripping and single-sheet separation of sheet metal, is characterized in that, The A gripper (31) and the B gripper (32) are connected by a bidirectional screw mechanism (34) and driven by a second drive mechanism (9) to move symmetrically closer or further away; the front end of the gripper (33) is provided with an inlet ramp (331) and the surface of the gripper (33) is provided with an anti-slip coating layer (332).

4. A robotic arm suitable for batch gripping and single-sheet separation of sheet metal according to claim 1, characterized in that, The suction cup assembly (42) includes a connecting rod (421) and a suction cup body (422). The upper end of the connecting rod (421) is movably inserted through the suction cup bracket (41). The elastic buffer (43) is a compression spring sleeved on the outer periphery of the connecting rod (421). The two ends of the compression spring abut against the suction cup bracket (41) and the limiting part (423) at the lower end of the connecting rod (421), respectively.

5. A robotic arm suitable for batch gripping and single-sheet separation of sheet metal according to claim 1, characterized in that, The vibration mechanism (5) includes a reciprocating cylinder assembly (51), which drives the suction cup bracket (41) to generate vertical vibration with a frequency of 10 to 20 Hz and an amplitude of 1 to 3 mm when the vibration mechanism (5) is activated.

6. A robotic arm suitable for batch gripping and single-sheet separation of sheet metal according to claim 1, characterized in that, The gripping rod (33) has an internal air passage (333). The upper surface of the end of the gripping rod (33) away from the center of the main frame (2) of the equipment has an air hole (334) that communicates with the air passage (333). A compressed air source (10) is provided on one side of the outer wall of the main support (1). The air passage (333) is connected to the compressed air source (10) through a pipeline and is controlled to open and close. The air outlet of the air hole (334) points to the interlayer gap at the bottom edge of the plate assembly.

7. A robotic arm suitable for batch gripping and single-sheet separation of sheet metal according to claim 1, characterized in that, The main frame (2) of the equipment is also equipped with a pre-pressure roller frame (11) on the front side along the first horizontal direction. The outer surface of the pre-pressure roller frame (11) is provided with several freely rotatable elastic rubber-coated rollers (111). The pre-pressure roller frame (11) is floatingly connected to the main frame (2) of the equipment through an elastic guide structure (112), so that the lowest point of the elastic rubber-coated rollers (111) is lower than the height of the initial contact plane of the suction cup assembly (42) when in operation.

8. A robotic arm suitable for batch gripping and single-sheet separation of sheet metal according to claim 7, characterized in that, At least one of the elastic coated rollers (111) is provided with a rotary encoder (113) at its shaft for detecting the jumping signal generated by the elastic coated roller (111) due to the unevenness of the plate surface.

9. A robotic arm suitable for batch gripping and single-sheet separation of sheet metal according to claim 3, characterized in that, It also includes a displacement detection device (12), which is installed on one side of the outer wall of the main frame (2) of the equipment. The second drive mechanism (9) automatically adjusts the distance between the A gripper (31) and the B gripper (32) according to the preset plate width value.

10. A robotic arm suitable for batch gripping and single-sheet separation of sheet metal according to claim 1, characterized in that, The suction cup assembly (4) includes multiple suction cup components (42) arranged in an array. The vacuum system (6) is connected to each suction cup component (42) through a multi-channel gas distribution block (61) and several independently controlled solenoid valves (62). A photoelectric sensor array (13) is also installed on the main frame (2) of the device to scan the contour of the upper surface of the plate assembly before adsorption. The solenoid valve (62) introduces vacuum only to the suction cup component (42) located above the solid area of ​​the plate according to the feedback of the photoelectric sensor array (13).

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