A hole making device with floating pressing function

Abstract

The application discloses a hole making device with floating pressing function and particularly relates to the technical field of drilling devices, which comprises a robot, an electric control cabinet, a control box, a drilling workbench and an oil-free air compressor. A mounting plate is fixedly installed at the execution end of the robot. A slide rail is fixedly installed at the front end of the mounting plate. A slide base is slidably installed on the slide rail. A mounting seat is installed on the slide base. A bottom plate is fixedly installed at the bottom of the mounting plate. The hole making device with floating pressing function can detect the contact force in real time through a pressure sensor and dynamically adjust the air pressure in combination with a pneumatic floating platform, so that the pressing force is constant during drilling, and the hole position deviation, burr or tearing caused by the uneven surface of a workpiece or the positioning error of the robot is avoided. The floating air bag can compensate the height difference of the surface of the workpiece in multiple dimensions, so that the contact head is always close to the curved surface, the drilling perpendicularity and the depth consistency are ensured, and the hole making device is particularly suitable for the machining of complex curved surfaces such as aircraft skin.

Description

Technical Field

[0001] This invention relates to the field of hole-making equipment technology, and in particular to a hole-making device with a floating clamping function. Background Technology

[0002] Modern aircraft face increasingly stringent safety and service life requirements, with fatigue life requirements now reaching tens of thousands or even eighty thousand flight hours. Currently, aircraft structures widely employ mechanical connections, with a large aircraft containing as many as 1.5 million to 2 million connection holes. The loads borne by the aircraft during flight are primarily transmitted through these connections, leading to significant stress concentrations around the holes. Industry statistics show that 70% of aircraft fatigue failures originate at structural connections, and up to 80% of fatigue cracks initiate at these connection holes. Therefore, the quality of these connection holes directly determines the service life and reliability of the aircraft structure.

[0003] In the field of automated aircraft assembly, the use of industrial robots for drilling has become a key technology for improving efficiency and quality. However, in practical applications, this technology still faces several serious challenges. Because aircraft skin and other components are mostly complex curved surfaces with inherent manufacturing tolerances and assembly errors, the surfaces are uneven. In existing technologies, robot end effectors are mostly rigid structures, making it difficult to actively adapt to these surface changes during drilling. This easily leads to: excessive clamping force at high points on the surface, potentially causing indentations or even damage to the workpiece surface; and insufficient clamping force or "virtual pressure" at low points. Insufficient clamping force can trigger cutting vibration, resulting in rough hole walls, exit burrs, non-circular hole shapes, or even "nail pulling," severely deteriorating hole wall quality and becoming a source of fatigue crack initiation. Therefore, this invention provides a drilling device with a floating clamping function, hoping to solve the above problems. Summary of the Invention

[0004] The main objective of this invention is to provide a hole-making device with a floating clamping function, which can effectively solve the problems in the background art.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A hole-making device with floating clamping function includes a robot, an electrical control cabinet, a control box, a drilling workbench, and an oil-free air compressor. The robot's execution end is fixedly mounted with a mounting plate. A slide rail is fixedly mounted at the front end of the mounting plate. A slide block is slidably mounted on the slide rail. A mounting seat is mounted on the slide block. A base plate is fixedly mounted at the bottom of the mounting plate. A connecting seat is fixedly mounted on the mounting seat. A motor is mounted on the connecting seat. A drill bit is fixedly mounted at the bottom output end of the motor. A floating clamping platform is fixedly mounted at the bottom of the base plate. A contact is mounted at the bottom of the floating clamping platform. A pressure sensor is installed between the contact and the floating clamping platform.

[0007] Preferably, the floating clamping platform includes an upper flange, a sealing ring, a floating airbag, an air chamber piston assembly, a main cylinder, a sealing positioning ring, a lower flange, and an outer shell. The upper flange is bolted to the bottom of the base plate, and the air chamber piston assembly is bolted to the bottom of the upper flange. An annular groove is provided on the upper part of the inner wall of the upper flange. The upper part of the floating airbag is embedded in the annular groove, and the sealing ring is bolted to the annular groove. The upper part of the floating airbag is clamped between the sealing ring and the upper flange. The lower flange is bolted to the outer shell. In the middle of the bottom wall of the housing, the main cylinder body is sleeved on the outside of the air chamber piston assembly and the lower flange. An annular groove is formed in the middle of the air chamber piston assembly, and the upper end of the main cylinder body is fitted into the annular groove. The sealing positioning ring securely connects the main cylinder body to the lower flange with bolts. A pipe is fixedly installed in the middle of the upper end of the lower flange, extending upwards through the air chamber piston assembly and into the interior of the upper flange. An annular groove is formed on the upper part of the outer wall of the pipe at the upper end of the lower flange, and the lower end of the floating airbag is fitted into the annular groove. The floating airbag, upper flange, and air chamber piston are all present in the design. The components, main cylinder, and lower flange form a sealed air chamber. The contact is installed at the bottom of the outer casing, and an air cushion element is installed between the lower flange and the bottom wall of the outer casing. Through the adaptive adjustment of the floating clamping platform, the contact maintains a perpendicular and stable contact with the workpiece surface, effectively compensating for robot absolute positioning errors and workpiece theoretical model deviations. This fundamentally avoids problems such as hole position deviations, elliptical holes, or burrs at the hole opening caused by angle deviations or uneven clamping. The constant clamping force provides reliable workpiece stability and effectively suppresses vibrations generated during drilling, thereby reducing... This device reduces the damage to the hole wall caused by cutting vibration and achieves a better surface finish. The floating airbag can generate multi-dimensional elastic deformation under air pressure control, enabling the device to automatically adapt to the contour changes of complex curved surfaces such as aircraft skin, and effectively compensate for local height differences on the workpiece surface (within ±2mm). Traditional rigid clamping is prone to causing clamping force concentration or false pressure on curved workpieces. The floating clamping of this device achieves a combination of rigidity and flexibility, which can provide sufficient clamping force and conform to the curved surface like a "hand", avoiding workpiece deformation or indentation damage caused by improper clamping.

[0008] Preferably, the upper flange has an air inlet, and the air chamber piston assembly has a channel that connects the air inlet to the sealed air chamber. The air inlet is connected to an oil-free air compressor via a pipe.

[0009] Preferably, a sealing gasket is provided between the gas chamber piston assembly and the upper flange.

[0010] Preferably, an electric cylinder is mounted on the mounting plate, and the electric cylinder drives the slide block to slide on the slide rail.

[0011] Preferably, a protective cover is fixedly installed on the upper end of the base plate and the front end of the mounting plate, and the slide rail, slide seat, mounting seat, connecting seat, and motor are all covered inside the protective cover.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] This invention discloses a hole-making device with floating clamping function. The device detects the contact force in real time through a pressure sensor and dynamically adjusts the air pressure in combination with a pneumatic floating platform to ensure that the clamping force is constant during the drilling process. This avoids hole position deviation, burrs or tearing caused by uneven workpiece surface or robot positioning error. The floating airbag can compensate for the height difference of the workpiece surface in multiple dimensions, so that the contact head is always in close contact with the curved surface, ensuring the verticality and depth consistency of the drilling. It is particularly suitable for machining complex curved surfaces such as aircraft skin. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0015] Figure 2 This is a schematic diagram showing the connection of some structures of the present invention;

[0016] Figure 3 This is a first cross-sectional view of the floating clamping platform of the present invention;

[0017] Figure 4 This is a second cross-sectional view of the floating clamping platform of the present invention;

[0018] Figure 5 This is an exploded view of the floating clamping platform of the present invention.

[0019] In the diagram: 1. Robot; 2. Mounting plate; 3. Slide rail; 4. Slide block; 5. Mounting base; 6. Connecting base; 7. Motor; 8. Floating clamping platform; 9. Contact; 10. Pressure sensor; 81. Upper flange; 82. Sealing ring; 83. Floating airbag; 84. Air chamber piston assembly; 85. Main cylinder; 86. Sealing positioning ring; 87. Lower flange; 88. Outer shell; 89. Air cushion element; 12. Base plate; 13. Electrical control cabinet; 14. Control box; 15. Drilling workbench; 16. Oil-free air compressor; 17. Electric cylinder; 11. Protective cover. Detailed Implementation

[0020] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0021] like Figure 1-5As shown, a hole-making device with floating clamping function includes a six-axis industrial robot 1 (six-axis industrial robotic arm) as the main actuator, an integrated electrical control cabinet 13, a control box 14, a drilling worktable 15 for fixing the workpiece, and an oil-free air compressor 16 that provides a clean air source for the pneumatic system. The end effector of the robot 1 is rigidly connected to a mounting plate 2. A precision slide rail 3 is mounted on the front end of the mounting plate 2. A slide block 4 that can slide along its axial direction is fitted on the slide rail 3. A mounting base 5 is further fixed to the slide block 4. To enhance structural stability, a base plate 12 is fixed to the bottom of the mounting plate 2. A motor 7, serving as a power source, is mounted on the mounting base 5 via a connecting seat 6. The motor 7 is preferably an electric spindle, with the drill bit directly mounted at its bottom output end to achieve high-speed drilling. A floating clamping platform 8 is fixedly mounted at the bottom of the base plate 12. The bottom of the platform is provided with a contact 9 that directly contacts the workpiece surface. A high-precision pressure sensor 10 is connected in series between the contact 9 and the floating clamping platform 8. This pressure sensor 10 is used to detect and provide feedback on the contact force between the tool and the workpiece during the drilling process in real time, forming a key sensing link in the closed-loop control system. The slide 4 is driven by the modular electric cylinder 17 mounted on the mounting plate 2, thereby driving the entire drill bit assembly motor 7 and the drill bit to make precise feed movements along the slide rail 3 to complete the drilling entry and exit actions.

[0022] The floating compression platform 8 has a sealed air chamber inside, which is connected to the oil-free air compressor 16 through a pipeline. The core elastic element inside the floating compression platform 8—the floating airbag 83—can produce multi-dimensional elastic deformation under controlled air pressure. During operation, the real-time force signal detected by the pressure sensor 10 is transmitted to the central controller in the control box 14 or the electrical control cabinet 13. The controller compares this signal with the preset force target value and outputs control commands to the air pressure regulating element, such as a proportional valve, to dynamically adjust the air pressure entering the floating clamping platform 8. The adjustment logic is as follows: when the detected pressure is greater than the set value, the system reduces the air pressure, the platform floats downward, and the clamping force is reduced; when the detected pressure is less than the set value, the system increases the air pressure, the platform floats upward, and the clamping force is increased. The robot 1 is responsible for positioning the entire device to the hole to be processed. Then, the contact 9 of the floating clamping platform 8 first contacts the workpiece surface and, under the above adaptive control mechanism, automatically adjusts and maintains a constant optimal clamping force to compensate for the unevenness of the workpiece surface, stabilize the workpiece, and eliminate vibration. After the clamping force stabilizes, the motor 7 starts, and the electric cylinder 17 pushes the drill bit to complete the drilling operation.

[0023] The floating clamping platform 8 includes an upper flange 81, a sealing ring 82, a floating airbag 83, an air chamber piston assembly 84, a main cylinder 85, a sealing positioning ring 86, a lower flange 87, and an outer shell 88. The upper flange 81 serves as the upper mounting base of the platform and is fixedly installed on the bottom of the base plate 12 by bolts, achieving a rigid connection with the execution end of the robot 1. The upper flange 81 itself is designed with an air inlet, serving as the entrance for external compressed air to enter the platform. An annular groove is machined on the upper part of the inner wall of the upper flange 81. The floating airbag 83, as the core elastic deformation element, has its upper edge embedded in this annular groove. Subsequently, the sealing ring... 82 is bolted and fixed in the annular groove, thereby tightly clamping the upper part of the floating airbag 83 between the sealing ring 82 and the groove wall of the upper flange 81, forming a reliable upper static seal. The air chamber piston assembly 84 is bolted to the bottom of the upper flange 81, and the lower flange 87 is bolted to the middle of the bottom wall of the outer casing 88. An air cushion element 89 is installed between the lower flange 87 and the bottom wall of the outer casing 88. The main cylinder body 85, as the main housing, is sleeved on the outside of the air chamber piston assembly 84 and the lower flange 87. An annular groove is opened in the middle of the air chamber piston assembly 84, and the upper part of the main cylinder body 85... The end of the floating airbag 83 is embedded and engaged in this groove to achieve initial positioning and sealing. The sealing positioning ring 86 is then tightly connected to the lower end of the main cylinder 85 and the lower flange 87 by bolts to ensure a seal at this point. A central pipe is fixedly installed in the middle of the upper end of the lower flange 87. This pipe extends upward, passes through the air chamber piston assembly 84 in sequence, and finally extends into the internal cavity of the upper flange 81. Another annular groove is opened on the upper outer wall of this central pipe. The lower end of the floating airbag 83 is embedded and engaged in this groove to achieve fixation and sealing of its lower end. Through the above structure, the upper flange 81, the floating airbag 83, and the air chamber piston assembly are connected. The components 84, the main cylinder 85, and the lower flange 87 together form a complete sealed air chamber. External compressed air enters through the air inlet of the upper flange 81, passes through the corresponding connecting channels inside the air chamber piston assembly 84, and is finally injected into this sealed air chamber. The contact 9 is directly installed at the bottom of the outer shell 88 as the terminal that directly contacts the workpiece surface. When the air pressure in the sealed air chamber changes, it acts on the floating airbag 83 to cause it to produce axial or multidimensional elastic deformation, which in turn drives the contact 9 to produce floating displacement through the lower flange 87 and the outer shell 88. The pressure sensor 10 integrated above the contact 9 monitors this clamping force in real time.

[0024] A sealing gasket is provided between the air chamber piston assembly 84 and the upper flange 81. Its main function is to achieve a static seal between the two and fill any gaps that may exist on the metal joint surface due to microscopic unevenness. This is the key channel interface for compressed air to enter the sealed air chamber composed of the air chamber piston assembly 84 and other parts from the air inlet of the upper flange 81. If there is a leak here after assembly, it will directly lead to a loss of compressed air pressure, making it impossible for the entire floating clamping platform 8 to establish a stable working pressure. This will cause the adaptive clamping function to fail and the platform to be unable to accurately respond to the air pressure adjustment commands of the control system. When bolts are used to tighten the gasket, the platform will be unable to achieve a stable working pressure. When the air chamber piston assembly 84 is fastened to the upper flange 81, the sealing gasket undergoes elastic or plastic deformation under the action of the bolt preload, tightly filling the contact surface between the two metal flanges, thereby forming a leak-free sealing interface. This ensures that compressed air can only enter the air chamber through the pre-designed channels and will not escape from the mating surface. At the same time, this sealing gasket, together with other sealing elements inside the platform such as the sealing ring 82, the sealing positioning ring 86, and the edge seal of the floating airbag 83 itself, constitutes a complete multi-seal system, ensuring the long-term reliability and stability of the entire sealed air chamber under working pressure.

[0025] A protective cover 11 is fixedly installed on the upper end of the base plate 12 and the front end of the mounting plate 2. This protective cover 11 is constructed as a closed or semi-closed shell structure that completely encloses the precision transmission and drive components such as the slide rail 3, slide block 4, mounting base 5, connecting base 6, and motor 7. The protective cover serves to protect and isolate the components. During the drilling process, a large amount of metal shavings, dust, and potentially used coolant are generated. If these contaminants directly adhere to the moving parts such as the slide rail 3 and slide block 4, they will drastically accelerate wear, leading to movement jamming, loss of precision, and even damage to the motor 7. This design, through the protective cover 11, forms a physical barrier, effectively isolating these harmful factors and ensuring the long-term operational precision and service life of the core moving components. The protective cover 11 protects high-speed moving transmission components such as the slide block driven by the electric cylinder 17. 4 and the high-speed rotating motor 7 are isolated from the external environment, effectively preventing the risk of operators' hands or clothing getting caught in the shavings. It also avoids injuries caused by flying chips, meeting the safety requirements of industrial equipment. The protective cover 11 is fixed together with the upper end of the base plate 12 and the front end of the mounting plate 2. This design makes it tightly integrated with the main load-bearing structure, enhancing the rigidity and stability of the overall device and avoiding vibration or deformation that may be caused by a single mounting point. Its shell structure also helps to suppress and absorb some vibration and noise. At the same time, while ensuring protection, the protective cover 11 is usually designed to be openable or detachable (such as by means of hinges, quick-release screws, etc.) to facilitate regular cleaning, lubrication, and replacement of vulnerable parts of the internal slide rails 3 and sliders, ensuring the convenience of equipment maintenance.

[0026] The working principle of this invention is as follows:

[0027] Step 1: Initial State

[0028] Robot 1, carrying the entire drilling device, is in a standby position. The sealed air chamber inside the floating clamping platform 8 maintains a preset initial air pressure. The platform is in the center position, the electric cylinder 17 is in the retracted state, and the drill bit is raised.

[0029] Step 2: Robot positioning and contact with the workpiece

[0030] The control system drives the robot 1 to move according to the pre-programmed path or the hole position data obtained by visual scanning, and accurately positions the device to the hole to be processed. The robot 1 moves downward so that the contact 9 at the bottom of the floating clamping platform 8 contacts the workpiece surface before the drill bit.

[0031] Step 3: Adaptive clamping

[0032] Sensing: When the contact 9 contacts the workpiece, the pressure sensor 10 immediately detects the contact force signal and transmits it to the central controller of the control box 14 in real time;

[0033] Decision: The controller compares the received actual force value with the target force value set in the program, and calculates the amount of air pressure adjustment that needs to be increased or decreased based on the difference;

[0034] Execution: The controller sends a command to the air pressure regulation system, such as a proportional valve, to adjust the air pressure delivered by the oil-free air compressor 16 to the floating clamping platform 8. If the actual force is greater than the set force, the air pressure in the sealed air chamber is reduced. After the air pressure is reduced, the deformation of the floating air bag 83 decreases. Under the weight of the device or external action, the platform drives the contact 9 to float downward, thereby reducing the clamping force. If the actual force is less than the set force, the air pressure in the sealed air chamber is increased. The increased air pressure causes the floating air bag 83 to expand and deform, generating an upward force that pushes the platform to drive the contact 9 to float upward, thereby increasing the clamping force.

[0035] Step 4: Stabilize and tighten the hole and proceed with drilling.

[0036] Once the force value fed back by the pressure sensor 10 stabilizes within the target range, the control system confirms that the clamping state is ready. Subsequently, the control system issues a command: the electric spindle of motor 7 starts, driving the drill bit to rotate at high speed, the electric cylinder 17 actuates, pushing the slide 4 to feed precisely along the slide rail 3, the drill bit moves downward, and drilling begins. Throughout the drilling process, the adaptive clamping control works continuously, effectively absorbing cutting vibration, resisting workpiece deformation, and ensuring the quality and perpendicularity of the hole.

[0037] Step 5: Complete drilling and reposition the equipment.

[0038] After the drilling reaches the predetermined depth, the electric cylinder 17 moves in the opposite direction to retract the drill bit from the hole. The motor 7 stops rotating, and the pressure sensor 10 detects that the contact force has disappeared. The controller then controls the pneumatic system to restore the air pressure of the floating clamping platform 8 to its initial value. The robot 1 moves to the next drilling point and repeats the above process.

[0039] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A hole-making device with a floating clamping function, characterized in that: The system includes a robot (1), an electrical control cabinet (13), a control box (14), a drilling workbench (15), and an oil-free air compressor (16). The robot (1) has a mounting plate (2) fixedly installed at its execution end. A slide rail (3) is fixedly installed at the front end of the mounting plate (2). A slide block (4) is slidably installed on the slide rail (3). A mounting seat (5) is installed on the slide block (4). A base plate (12) is fixedly installed at the bottom of the mounting plate (2). A connecting seat (6) is fixedly installed on the mounting seat (5). A motor (7) is installed on the connecting seat (6). A drill bit is fixedly installed at the bottom output end of the motor (7). A [missing information - likely a component or component] is fixedly installed at the bottom of the base plate (12). A floating clamping platform (8) is provided, with a contact (9) installed at its bottom. A pressure sensor (10) is installed between the contact (9) and the floating clamping platform (8). The floating clamping platform (8) includes an upper flange (81), a sealing ring (82), a floating airbag (83), an air chamber piston assembly (84), a main cylinder (85), a sealing positioning ring (86), a lower flange (87), and an outer shell (88). The upper flange (81) is fixedly installed at the bottom of the base plate (12) by bolts. The air chamber piston assembly (84) is fixedly installed at the bottom of the upper flange (81) by bolts. The upper part of the inner wall of the upper flange (81) is... An annular groove is provided, and the upper part of the floating airbag (83) is embedded in the annular groove. At the same time, the sealing ring (82) is fixedly installed in the annular groove by bolts. The upper part of the floating airbag (83) is sandwiched between the sealing ring (82) and the upper flange (81). The lower flange (87) is fixedly installed in the middle of the bottom wall of the outer shell (88) by bolts. The main cylinder (85) is sleeved on the outside of the air chamber piston assembly (84) and the lower flange (87). An annular groove is provided in the middle of the air chamber piston assembly (84). The upper end of the main cylinder (85) is stuck in the annular groove. The sealing positioning ring (86) connects the main cylinder (85) to the lower flange by bolts. (87) Sealed and fixed connection, a pipe is fixedly installed in the middle of the upper end of the lower flange (87), and the pipe extends upward through the air chamber piston assembly (84) and extends into the interior of the upper flange (81). An annular groove three is opened on the upper part of the outer wall of the pipe at the upper end of the lower flange (87). The lower end of the floating airbag (83) is stuck in the annular groove three. The floating airbag (83), the upper flange (81), the air chamber piston assembly (84), the main cylinder (85) and the lower flange (87) form a sealed air chamber. The contact (9) is installed at the bottom of the outer shell (88). An air cushion element (89) is installed between the lower flange (87) and the bottom wall of the outer shell (88).

2. The hole-making device with floating clamping function according to claim 1, characterized in that: The upper flange (81) has an air inlet, and the air chamber piston assembly (84) has a channel that communicates with the air inlet and the sealed air chamber. The air inlet is connected to the oil-free air compressor (16) through a pipe.

3. A hole-making device with floating clamping function according to claim 2, characterized in that: A sealing gasket is provided between the gas chamber piston assembly (84) and the upper flange (81).

4. A hole-making device with floating clamping function according to claim 1, characterized in that: An electric cylinder (17) is installed on the mounting plate (2), and the electric cylinder (17) drives the slide block (4) to slide on the slide rail (3).

5. A hole-making device with floating clamping function according to claim 1, characterized in that: The upper end of the base plate (12) and the front end of the mounting plate (2) are jointly fixedly installed with a protective cover (11). The slide rail (3), slide seat (4), mounting seat (5), connecting seat (6), and motor (7) are all covered inside the protective cover (11).

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