A multi-stage adaptive machining auxiliary clamping device
By using a multi-stage adaptive machining auxiliary clamping device and a cylindrical pin array to achieve conformal clamping of the workpiece surface, combined with a locking and alignment module, the problem of hole-making accuracy for workpieces with large curvature is solved, achieving efficient and high-precision hole-making processing.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- DALIAN UNIV OF TECH
- Filing Date
- 2024-08-21
- Publication Date
- 2026-05-26
AI Technical Summary
Existing pressure foot devices are difficult to adapt to workpieces with large curvature or variable curvature, resulting in large workpiece deformation and poor hole-making accuracy, which makes it difficult to meet the hole-making requirements of aerospace, energy and power and marine engineering fields.
Design a multi-level adaptive machining auxiliary clamping device, including a base module, a conformal module, a locking module, and a deviation-correction module. The conformal clamping of the workpiece surface is achieved through a cylindrical pin array, the locking module ensures stability, and the deviation-correction module realizes perpendicularity detection and adjustment. The integrated structure improves adaptability.
It enables efficient and high-precision hole making for workpieces with large curvature, reduces workpiece deformation, improves hole making accuracy, expands the application range of pressure feet, and meets the processing needs of aerospace, energy and power and marine engineering.
Smart Images
Figure CN118849050B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of robotic automatic drilling and riveting technology, and in particular to a multi-stage adaptive machining auxiliary clamping device. Background Technology
[0002] With the increasing precision requirements for drilling in aerospace, energy, and marine engineering, traditional manual drilling has gradually become inadequate due to its low efficiency and poor accuracy. With the rise of digital systems and industrial robots, high-degree-of-freedom automated drilling technology using industrial robots with end effectors has rapidly developed. Pressure feet, as a crucial component of robotic drilling systems, play a role in clamping workpieces, improving the rigidity of the drilling system, eliminating layer gaps, and performing normal detection, making them an important research area in automated drilling technology.
[0003] Some research has been conducted both domestically and internationally on pressure foot devices for robotic drilling systems. Cheng Hui et al.'s invention, "A Geometric-Force Online Sensing Drilling and Riveting Pressure Foot Device and Online Sensing Method," patent publication number CN 115008257A, enables online monitoring of drilling and riveting forces, but its adaptability to curved surfaces has not been studied. Fu Pengqiang et al.'s invention, "A Clamping Module for an Automatic Drilling End Actuator," patent publication number CN 112757021A, effectively enhances the system's dynamic stiffness, suppresses vibrations generated during robot drilling, and eliminates interlayer gaps in laminated parts. However, this device is still only suitable for flat structures and is difficult to adapt to curved surfaces. Kevin Sitton et al.'s ONCE automatic drilling system, mentioned in their paper "ONe-sided Cell End effector Robotic Drilling System," was one of the earliest proposed methods to use pressure foot devices to assist robots in drilling to ensure processing quality. However, this system is also only studied for planar workpieces and is difficult to adapt to curved structures. The pressure foot devices described above are all rigid planar structures, which are more suitable for flat or small curvature workpieces. However, for large curvature workpieces, especially thin-walled parts, the planar pressure foot will cause large deformation after pressing the workpiece, resulting in poor hole diameter accuracy after drilling, making it difficult to meet the drilling requirements. Summary of the Invention
[0004] The purpose of this invention is to provide a multi-stage adaptive machining auxiliary clamping device to achieve conformal clamping of workpieces with large curvature or variable curvature, reduce workpiece deformation, and improve hole-making accuracy.
[0005] The technical solution of the present invention:
[0006] A multi-stage adaptive machining auxiliary clamping device includes: a base module 1, a conformal module 2, a locking module 3, and a deviation-correction module 4. The base module 1 is used to stably connect the pressure foot to the robot end effector and provide installation positions for the conformal module 2, the locking module 3, and the deviation-correction module 4. The conformal module 2 uses an array of cylindrical pins 201 to automatically adapt to the surface shape of workpieces with different curvatures and conform to the shape. The locking module 3 is used to lock the conformed cylindrical pin array 201 to ensure the stability of the conformation. The deviation-correction module 4 is used to correct the perpendicularity between the tool axis and the workpiece surface before drilling. The pressure foot is a multi-stage adaptive machining auxiliary clamping device.
[0007] Further, the base module 1 includes a base 101, a pressure foot body 102, a drive unit rear cover plate 103, a pin fixing block 104, and a pin base 105. The base 101 is fixed to the front end of the robot's end effector during use; the pressure foot body 102 is fixedly connected to the base 101; the drive unit rear cover plate 103 is fixed to the pressure foot body 102, providing an installation position for the drive unit 301 in the locking module 3; the pin base 105 is fixed to the pressure foot body 102; the pin fixing block 104 is fixedly connected to the pin base 105, and the pin fixing block 104 and the pin base 105 provide springback and assembly space for the cylindrical pin 201 in the conformal module 2, and can press against the pin fixing plate 204 and the pin connecting plate 203.
[0008] Furthermore, the conformal module 2 includes a cylindrical pin 201, a return spring 202, and a baffle. The cylindrical pin 201 is divided into three segments, A, B, and C, from the tail end to the head end. The shaft diameter Rc of segment C is the largest, the shaft diameter Rb of segment B is the smallest, and the shaft diameter Ra of segment A is between that of segment C and segment B. The baffle is fixed to the base module 1. An array of through holes is formed on the baffle, and the through holes are clearance-fitted with the cylindrical pins 201. The return spring 202 and the baffle are slidably sleeved on the B section of the cylindrical pins 201 in sequence. The two end faces of the baffle are in contact with the end face of the A section of the cylindrical pins 201 and one end of the return spring 202, respectively. The other end of the return spring 202 is in contact with the end face of the C section of the cylindrical pins 201. The cylindrical pins 201 on the same baffle together form a cylindrical pin array. The cylindrical pin array is tangent to the inner wall of the assembly space reserved on the base module 1 at the C section. The assembly space reserved on the base module 1 provides guidance for the extension and retraction of the cylindrical pins 201.
[0009] Preferably, the baffle includes a pin connecting plate 203 and a pin fixing plate 204. The pin connecting plate 203 has an array of circular through holes, and the pin fixing plate 204 has gourd-shaped irregular holes. The diameter of the larger circular hole of the irregular hole is equal to the diameter of the circular through hole on the pin connecting plate 203, and is larger than the shaft diameter Ra of the cylindrical pin 201A segment but smaller than the shaft diameter Rc of the cylindrical pin 201C segment. The diameter of the smaller circular hole of the irregular hole is larger than the shaft diameter Rb of the cylindrical pin 201B segment but smaller than the shaft diameter Ra of the cylindrical pin 201A segment. The pin connecting plate 203 and the pin fixing plate 204 have the same plate size. When they are completely overlapped, the minimum diameter of the through hole is formed to fit the clearance of the cylindrical pin 201B segment. After the pin connecting plate 203 and the pin fixing plate 204 are overlapped and fixed to each other, the cylindrical pin 201 can be positioned.
[0010] More preferably, the pin connecting plate 203 and the pin fixing plate 204 are completely overlapped and connected by screws, and the two are placed together in the reserved space of the pin base 105 and the pin fixing block 104 to achieve clamping and fixing.
[0011] Furthermore, the locking module 3 includes a drive unit 301, a lever 302, a lever pin 303, and a pressure block 305. The drive unit 301 is fixed to the base module 1, and the pressure block 305 is disposed in the base module 1, capable of contacting one side of the cylindrical pin array 201, and having a certain clamping space. One end of the lever 302 is connected to the drive unit 301, and the other end is rotatably connected to the base module 1 through the lever pin 303. One end of the lever 302 is driven by the drive unit 301, and the other end can rotate relative to the base module 1 around the lever pin 303, thereby clamping the pressure block 305.
[0012] Preferably, the locking module 3 further includes a locking block 304 and a drive unit connecting plate 306. The lever pin 303 passes through the lever 302 and the locking block 304 respectively, and is in clearance fit with the lever 302 and the locking block 304 to provide a fulcrum for the rotation of the lever 302. The locking block 304 is fixedly connected to the base module 1. The drive unit 301 is fixed on the drive unit connecting plate 306, and then the assembly of the drive unit 301 and the drive unit connecting plate 306 is positioned on the base module 1 by three-sided positioning.
[0013] More preferably, the locking block 304 is fixedly connected to the pin fixing block 104. The drive unit 301 and the drive unit connecting plate 306 are fixed together on the drive unit rear cover plate 103 and locked with screws.
[0014] Furthermore, the method-finding module 4 includes a fixed base 401 and a laser generator 402; the fixed base 401 is fixed on the base module 1; the laser generator 402 is positioned on the fixed block 401 through three-sided positioning.
[0015] Preferably, the fixing seat 401 is positioned on the pin fixing block 104 from three sides and fixed by screws.
[0016] According to specific embodiments provided by the present invention, the present invention discloses the following technical effects:
[0017] This invention enables conformal clamping of workpieces with different curvatures through a conformal module, reducing workpiece deformation. The locking module, in conjunction with the base module, ensures consistency between the contact surface of the cylindrical pin and the workpiece surface after conformal clamping, improving conformal accuracy. The normal alignment module enables rapid and accurate detection and adaptive adjustment of the workpiece normal. The high integration of the pressure foot conformal module, locking module, and normal alignment module results in a compact overall structure, improving the accessibility and versatility of the pressure foot, expanding its working range, and ultimately achieving efficient and high-precision hole machining of workpieces with curvature in aerospace, energy, and marine engineering fields. Attached Figure Description
[0018] Figure 1 This is an isometric view of the multi-stage adaptive machining-assisted clamping device of the present invention;
[0019] Figure 2 This is a partial cross-sectional view of the conformal module of the present invention in a freely stretching state;
[0020] Figure 3 This is a partial cross-sectional view of the conformal module of the present invention;
[0021] Figure 4 This is a schematic diagram of the locking unit installation;
[0022] In the diagram: 1-Base module; 2-Follow-form module; 3-Locking module; 4-Alignment module; 101-Base; 102-Pressure foot body; 103-Drive unit rear cover; 104-Pin fixing block; 105-Pin base; 201-Cylindrical pin; 202-Reset spring; 203-Pin connecting plate; 204-Pin fixing plate; 301-Drive unit; 302-Lever; 303-Lever pin; 304-Locking block; 305-Pressure block; 401-Fixing base; 402-Laser generator. Detailed Implementation
[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. 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.
[0024] Reference Figure 1 A multi-stage adaptive machining auxiliary clamping device includes: a base module 1, a conforming module 2, a locking module 3, and a deviation-correction module 4. The base module 1 is used to stably connect the pressure foot to the robot end effector and provides installation positions for the conforming module 2, locking module 3, and deviation-correction module 4. The conforming module 2 uses an array of cylindrical pins 201 to automatically adapt to the surface shape of workpieces with different curvatures and conform to the shape. The locking module 3 is used to lock the conformed cylindrical pin array 201 to ensure the stability of the conformation. The deviation-correction module 4 is used to correct the perpendicularity of the tool axis to the workpiece surface before drilling. The pressure foot is a multi-stage adaptive machining auxiliary clamping device.
[0025] Reference Figure 1 and Figure 2 The base module 1 includes a base 101, a pressure foot body 102, a drive unit rear cover plate 103, a pin fixing block 104, and a pin base 105. The base 101 is fixed to the front end of the robot's end effector with screws during use; the pressure foot body 102 is fixedly connected to the base 101 with screws; the drive unit rear cover plate 103 is fixed to the pressure foot body 102 with screws, providing an installation position for the drive unit 301 in the locking module 3; the pin base 105 is fixed to the pressure foot body 102 with screws; the pin fixing block 104 is fixedly connected to the pin base 105, and the pin fixing block 104, through screws and the pin base 105, provides springback and assembly space for the cylindrical pin 201 in the conformal module 2, and can press against the pin fixing plate 204 and the pin connecting plate 203.
[0026] Reference Figure 1 and Figure 3The conformal module 2 includes a cylindrical pin 201, a return spring 202, a pin connecting plate 203, and a pin fixing plate 204. The cylindrical pin 201 is divided into three segments, A, B, and C, from its tail end to its head end. Segment C has the largest shaft diameter Rc, segment B has the smallest shaft diameter Rb, and segment A has a shaft diameter Ra between segments C and B. The pin connecting plate 203 has an array of circular through holes, and the pin fixing plate 204 has gourd-shaped irregular holes. The diameter of the larger circular hole in the irregular hole is equal to the diameter of the circular through holes on the pin connecting plate 203, and is larger than the shaft diameter Ra of segment A of the cylindrical pin 201 but smaller than the shaft diameter Rc of segment C. The diameter of the smaller circular hole in the irregular hole is larger than the shaft diameter Rb of segment B of the cylindrical pin 201 but smaller than the shaft diameter Ra of segment A of the cylindrical pin 201. The pin connecting plate 203 and the pin fixing plate 204 have the same plate size. When they are completely overlapped, they together reveal the minimum diameter of the through hole, which is clearance-fitted with section B of the cylindrical pin 201. After the pin connecting plate 203 and the pin fixing plate 204 are overlapped and fixed to each other with screws, the cylindrical pin 201 can be positioned. The pin connecting plate 203 and the pin fixing plate 204 are placed together in the reserved space between the pin base 105 and the pin fixing block 104 to achieve clamping and fixation. The return spring 202, the pin connecting plate 203, and the pin fixing plate 204 are sequentially slidably sleeved on section B of the cylindrical pin 201. The outer end face of the pin fixing plate 204 contacts the end face of section A of the cylindrical pin 201, the inner end face of the pin connecting plate 203 contacts one end of the return spring 202, and the other end of the return spring 202 contacts the end face of section C of the cylindrical pin 201. The cylindrical pins 201 on the same pin connecting plate 203 together form a cylindrical pin 201 array. The cylindrical pin 201 array is tangent to the inner wall of the assembly space reserved on the pin fixing block 104 of the base module 1 at section C. The assembly space reserved on the pin fixing block 104 provides guidance for the extension and retraction of the cylindrical pins 201.
[0027] Reference Figure 2 and Figure 4The locking module 3 includes a drive unit 301, a lever 302, a lever pin 303, a locking block 304, a pressure block 305, and a drive unit connecting plate 306. The pressure block 305 is disposed in the pin fixing block 104 of the base module 1, and can contact one side of the cylindrical pin array 201, and has a certain pressure space. One end of the lever 302 is connected to the drive unit 301, and the other end is rotatably connected to the pin fixing block 104 via the lever pin 303. One end of the lever 302 is driven by the drive unit 301, and the other end can rotate around the lever pin 303 relative to the pin fixing block 104, thereby pressing the pressure block 305. The locking module 3 also includes a locking block 304 and a drive unit connecting plate 306. The lever pin 303 passes through the lever 302 and the locking block 304 respectively, and is in clearance fit with the lever 302 and the locking block 304, providing a fulcrum for the rotation of the lever 302. The locking block 304 is fixedly connected to the pin fixing block 104 of the base module 1. The drive unit 301 is fixed on the drive unit connecting plate 306, and then the drive unit 301 and the drive unit connecting plate 306 are fixed together on the drive unit rear cover plate 103 by three-sided positioning, and locked by screws.
[0028] Reference Figure 1 and Figure 2 The alignment module 4 includes a fixed base 401 and a laser generator 402. The fixed base 401 is positioned on the pin fixing block 104 on three sides and is fixed with screws; the laser generator 402 is positioned on the fixed block 401 on three sides and is fixed with screws.
Claims
1. A multi-stage adaptive machining auxiliary clamping device, characterized in that, include: The system comprises a base module (1), a conformal module (2), a locking module (3), and a calibration module (4). The base module (1) is used to stably connect the pressure foot to the robot end effector and to provide installation positions for the conformal module (2), the locking module (3), and the calibration module (4). The conformal module (2) uses an array of cylindrical pins (201) to automatically adapt to the surface shape of workpieces with different curvatures and conform to the shape. The locking module (3) is used to lock the array of cylindrical pins (201) after conformation to ensure the stability of conformation. The calibration module (4) is used to calibrate the perpendicularity between the tool axis and the workpiece surface before drilling. The pressure foot is a multi-level adaptive machining auxiliary clamping device. The conformal module (2) includes a cylindrical pin (201), a return spring (202), and a baffle. The cylindrical pin (201) is divided into three segments, A, B, and C, from its tail end to its head end. The shaft diameter Rc of segment C is the largest, the shaft diameter Rb of segment B is the smallest, and the shaft diameter Ra of segment A is between that of segment C and segment B. The baffle is fixed on the base module (1), and an array of through holes are provided on the baffle. The through holes are clearance-fitted with the cylindrical pin (201). The return spring (202) and the baffle are slidably sleeved on the B segment of the cylindrical pin (201). The two ends of the baffle are in contact with the end face of segment A of the cylindrical pin (201) and one end of the return spring (202), respectively. The other end of the return spring (202) is in contact with the end face of segment C of the cylindrical pin (201). The cylindrical pins (201) on the same baffle together form a cylindrical pin (201) array. The cylindrical pin (201) array is tangent to the inner wall of the assembly space reserved on the base module (1) at segment C. The assembly space reserved on the base module (1) provides guidance for the extension and retraction of the cylindrical pins (201). The locking module (3) includes a drive unit (301), a lever (302), a lever pin (303), and a pressure block (305). The drive unit (301) is fixed on the base module (1), and the pressure block (305) is set in the base module (1) and can contact one side of the cylindrical pin array (201) and has a certain pressing space. One end of the lever (302) is connected to the drive unit (301), and the other end is rotatably connected to the base module (1) through the lever pin (303). One end of the lever (302) is driven by the drive unit (301), and the other end can rotate around the lever pin (303) relative to the base module (1) to press the pressure block (305).
2. The multi-stage adaptive machining auxiliary clamping device according to claim 1, characterized in that, The base module (1) includes a base (101), a pressure foot body (102), a drive unit rear cover plate (103), a pin fixing block (104), and a pin base (105). The base (101) is fixed to the front end of the robot end effector during use. The pressure foot body (102) is fixedly connected to the base (101). The drive unit rear cover plate (103) is fixed on the pressure foot body (102) to provide an installation position for the drive unit (301) in the locking module (3). The pin base (105) is fixed on the pressure foot body (102). The pin fixing block (104) is fixedly connected to the pin base (105). The pin fixing block (104) and the pin base (105) are used to provide springback and assembly space for the cylindrical pin (201) in the conformal module (2) and can press the pin fixing plate (204) and the pin connecting plate (203).
3. The multi-stage adaptive machining auxiliary clamping device according to claim 1, characterized in that, The method-based alignment module (4) includes a fixed base (401) and a laser generator (402); the fixed base (401) is fixed on the base module (1); the laser generator (402) is positioned on the fixed base (401) from three sides.
4. The multi-stage adaptive machining auxiliary clamping device according to claim 1, characterized in that, The baffle includes a pin connecting plate (203) and a pin fixing plate (204). The pin connecting plate (203) has an array of circular through holes, and the pin fixing plate (204) has gourd-shaped irregular holes. The diameter of the larger circular hole in the irregular hole is equal to the diameter of the circular through holes on the pin connecting plate (203), and is larger than the shaft diameter Ra of segment A of the cylindrical pin (201) but smaller than the shaft diameter Rc of segment C of the cylindrical pin (201). The diameter of the small round hole is larger than the shaft diameter Rb of section B of the cylindrical pin (201) and smaller than the shaft diameter Ra of section A of the cylindrical pin (201); the pin connecting plate (203) and the pin fixing plate (204) have the same plate size. After they are completely overlapped, they together show the minimum diameter of the through hole and the clearance fit of section B of the cylindrical pin (201). After the pin connecting plate (203) and the pin fixing plate (204) are overlapped and fixed to each other, they can position the cylindrical pin (201).
5. The multi-stage adaptive machining auxiliary clamping device according to claim 4, characterized in that, After the pin connecting plate (203) and the pin fixing plate (204) are completely overlapped, they are connected by screws, and the two are placed together in the reserved space of the pin base (105) and the pin fixing block (104) to achieve clamping and fixing.
6. The multi-stage adaptive machining auxiliary clamping device according to claim 1, characterized in that, The locking module (3) further includes a locking block (304) and a drive unit connecting plate (306). The lever pin (303) passes through the lever (302) and the locking block (304) respectively, and is in clearance fit with the lever (302) and the locking block (304) to provide a fulcrum for the rotation of the lever (302). The locking block (304) is fixedly connected to the base module (1). The drive unit (301) is fixed on the drive unit connecting plate (306), and then the drive unit (301) and the drive unit connecting plate (306) are positioned on the base module (1) by three-sided positioning.
7. The multi-stage adaptive machining auxiliary clamping device according to claim 6, characterized in that, The locking block (304) is fixedly connected to the pin fixing block (104); the drive unit (301) and the drive unit connecting plate (306) are fixed together on the drive unit rear cover plate (103) and locked by screws.
8. The multi-stage adaptive machining auxiliary clamping device according to claim 3, characterized in that, The fixing seat (401) is positioned on the pin fixing block (104) on three sides and fixed by screws.