A digital quick clamping device for multi-dimensional sensing of mirror milling force

Abstract

The present application belongs to the field of tooling design technology, and particularly relates to a multi-dimensional sensing mirror milling force digital fast clamping device. The device includes a support frame and a plurality of clamping mechanisms fixed to the support frame, each clamping mechanism including a first telescopic rod, a second telescopic rod and a chuck; one end of the first telescopic rod and one end of the second telescopic rod are respectively hinged to two support points of the support frame through a ball joint, the other end of the first telescopic rod and the other end of the second telescopic rod are hinged to each other, the chuck is arranged in front of one end where the first telescopic rod and the second telescopic rod are hinged to each other, and a three-axis sensor is arranged between the hinged end, and the chuck of each clamping mechanism is used to clamp the skin at multiple locations on both sides of the skin. The present application improves the clamping efficiency of mirror milling of large aircraft skin.

Description

Technical Field

[0001] The present application belongs to the field of tooling design technology, and in particular relates to a digital quick clamping device for multi-dimensional sensing mirror milling force. Background Art

[0002] Existing dual five-axis mirror milling equipment is mainly used for milling large and complex curved surface parts such as aircraft skins. It is widely used in processes such as milling and weight reduction, milling and opening windows, trimming and drilling of large and complex aircraft skin parts. During the mirror milling process of weakly rigid skin parts, the skin parts are very prone to vibration and deformation. Therefore, the mirror milling of weakly rigid skin parts of large aircraft places strict requirements on the dynamic response and rigidity of the clamping system. The current mirror milling equipment at home and abroad mainly uses a telescopic arm mechanism with multi-point clamping on all sides of the part for the clamping of skin parts. For the complex skin parts of large aircraft, the clamping time of the entire skin is too long, which seriously affects the efficiency of the mirror milling processing of the aircraft skin. At the same time, factors such as stress release, stress concentration, and changes in mirror milling force that occur in the skin parts during the processing process can easily affect the processing accuracy of the parts. Summary of the Invention

[0003] In order to solve the above problems, the present application provides a multi-dimensional sensing mirror milling force digital fast clamping device, which mainly includes a support frame and multiple clamping mechanisms fixed to the support frame, each clamping mechanism includes a first telescopic rod, a second telescopic rod and a clamping head;

[0004] One end of the first telescopic rod and one end of the second telescopic rod are respectively hinged to two supporting points of the support frame through a ball joint, and the other end of the first telescopic rod and the other end of the second telescopic rod are hinged to each other. The clamping head is arranged on the front side of one end where the first telescopic rod and the second telescopic rod are hinged to each other, and a three-axis sensor is arranged between the clamping end and the hinged end. The clamping heads of each clamping mechanism are used to clamp the skin at multiple positions on both sides of the skin.

[0005] Preferably, the first telescopic rod and the second telescopic rod are three-level or more telescopic rods, the telescopic rods of adjacent levels are locked by cam clamping shafts, and the outer part of the telescopic rod is provided with a protective sleeve made of a bellows.

[0006] Preferably, the three-axis sensor is a resistance strain sensor.

[0007] Preferably, the chuck includes an arc-shaped seat, a clamping jaw, a push rod and a locking nut. The arc-shaped seat has a first strip hole and a second strip hole on both sides along the circumference. The clamping jaw is located in the arc-shaped seat. The clamping jaw has a screw passing through the first strip hole. The screw is adapted to connect to the locking nut outside the arc-shaped seat. After the push rod passes through the second strip hole, it can tighten the skin located in the clamping jaw.

[0008] Preferably, the clamping jaw has a sliding rod passing through the second strip-shaped hole, the sliding rod has a through hole with an internal thread, the through hole is connected to the inner side surface of the clamping jaw, and the push rod has an external thread adapted to pass through the through hole.

[0009] Preferably, the clamping jaw has a support frame passing through the arc seat, the support frame has a through hole, the push rod passes through the through hole and is connected to the rocker arm, and the rocker arm is hinged on the support frame.

[0010] This application improves the clamping efficiency of mirror milling of large aircraft skins. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a structural schematic diagram of a preferred embodiment of the multi-dimensional sensing mirror milling force digital rapid clamping device of the present application.

[0012] Figure 2 It is a structural diagram of the clamping mechanism.

[0013] Figure 3 This is a schematic diagram of the left side structure of the chuck of a preferred embodiment of the present application.

[0014] Figure 4 yes Figure 3 Schematic diagram of the right side structure of the chuck of the illustrated embodiment.

[0015] Figure 5 It is a schematic diagram of the chuck structure of another preferred embodiment of the present application.

[0016] Among them, 100-clamping mechanism, 200-support frame, 300-skin, 1-ball joint, 2-first telescopic rod, 3-cam shaft, 4-protective cover, 5-three-axis sensor, 6-chuck, 61-arc seat, 611-first strip hole, 612-second strip hole, 62-clamping claw, 621-support frame, 63-push rod, 631-rocker arm, 64-locking nut, 7-second telescopic rod. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solutions and advantages of the implementation of this application clearer, the technical solutions in the implementation of this application will be described in more detail below in conjunction with the drawings in the implementation of this application. In the drawings, the same or similar numbers throughout represent the same or similar elements or elements with the same or similar functions. The described implementation is a part of the implementation of this application, not all of the implementations. The implementation described below with reference to the drawings is exemplary and is intended to be used to explain this application, and should not be understood as a limitation on this application. Based on the implementation in this application, all other implementations obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. The implementation of this application is described in detail below in conjunction with the drawings.

[0018] This application provides a multi-dimensional sensing mirror milling force digital fast clamping device, such as Figure 1 As shown, it mainly includes a support frame 200 and a plurality of clamping mechanisms 100 fixed on the support frame 200 , and the skin 300 is clamped and fixed by the plurality of clamping mechanisms 100 .

[0019] like Figure 2 As shown, each clamping mechanism 100 includes a first telescopic rod 2, a second telescopic rod 7, and a clamping head 6. One end of the first telescopic rod 2 and one end of the second telescopic rod 7 are respectively hinged to two support points of the support frame 200 via a ball joint 1. The other ends of the first telescopic rod 2 and the second telescopic rod 7 are hinged to each other. The clamping head 6 is arranged in front of the hinged end of the first telescopic rod 2 and the second telescopic rod 7, and a three-axis sensor 5 is disposed between the clamping head 6 and the hinged end. The clamping head 6 of each clamping mechanism 100 is used to clamp the skin 300 at multiple locations on both sides of the skin 300.

[0020] The dual-stage telescopic rod designed in this application enables precise multi-degree-of-freedom positioning of the clamping end within the XYZ three-dimensional space, meeting the needs of rapid clamping of skin workpieces with varying curvatures. During skin processing, the three-axis sensor 5 monitors the three-dimensional dynamic components of the cutting force in real time, enabling better optimization and adjustment of processing parameters. This device effectively solves the problem of skin deformation caused by traditional rigid clamping. Through force-position coordinated control, it can increase processing efficiency by over 40%, significantly improving the processing quality and efficiency of thin-walled aviation parts.

[0021] This application also includes a data acquisition module and a data display and recording analysis system. The data acquisition module uses a high-speed acquisition card connected to a three-axis sensor via a flexible cable to obtain real-time data from the three-axis sensor. This data is then sent to the data display and recording analysis system to display the milling force changes and guide skin clamping. The data display and recording analysis system is developed in C# and includes a data display function area, a data recording function area, and a data analysis function area.

[0022] The steps for using the multi-dimensional sensing mirror milling force digital quick clamping device and its supporting analysis system of the present application are as follows:

[0023] Step S1: Initialize the clamping mechanism, that is, distribute the clamping devices along the edge of the skin at an equal distance of 150±5mm, and then establish the skin global coordinate system through the laser tracker.

[0024] Step S2: Adaptive clamping: first perform preload (the initial pressure is usually set to 50N). After obtaining stress data through the three-axis sensor and data acquisition module, adjust the spatial position of the clamping point through the ball joint 1, the first telescopic rod 2, and the second telescopic rod 7.

[0025] Step S3: Clamp the skin 300 by the chuck 6 and perform mirror milling on the skin 300. The data during the milling process is monitored and recorded in real time by the data display and recording analysis system.

[0026] In step S2, each sensor needs to be calibrated in advance without pressure. After the tooling is erected, the changes in each sensor are observed and the sensor values ​​are adjusted to within a reasonable range. After the skin is clamped using the clamping device of this application, the surface error of the processed skin is ≤ 0.05mm, which improves the accuracy by 67% and the clamping efficiency by 40%.

[0027] In some optional embodiments, the first telescopic rod 2 and the second telescopic rod 7 are three-level or more telescopic rods, and the telescopic rods of adjacent levels are locked by a cam shaft 3. The outside of the telescopic rod is provided with a protective sleeve 4 made of a bellows.

[0028] The telescopic rod of the present application is supported by a high-strength alloy material. By designing a three-stage telescopic mechanism, it meets the clamping requirements during the milling process of skins of different models and sizes. A long guide mechanism is used in the telescopic tube to further improve the strength of the telescopic mechanism when it is fully extended, so that it maintains sufficient rigidity. On the other hand, the present application uses a protective cover 4 to enhance the surface corrosion protection of the telescopic rod and at the same time improve the stability of the telescopic rod. The steps for clamping the skin using the clamping device of the present application are as follows:

[0029] For aircraft skins of different models and sizes, the telescopic position of the telescopic rod of the clamping device is first adjusted preliminarily. Specifically, the cam clamp is opened to ensure that the three-stage telescopic rod structure can be smoothly extended and retracted, and the length of the three-stage telescopic rod is adjusted so that the end clamp is in the appropriate position of the edge of the clamped skin; then, the end clamp is controlled to firmly clamp the edge position of the aircraft skin to achieve locking and fixation of the skin; finally, the cam clamp is closed and the telescopic rod is tightened to complete the clamping of the aircraft skin by the entire clamping device.

[0030] In some optional implementations, the three-axis sensor 5 is a resistive strain sensor, which is suitable for high-frequency acquisition of dynamic milling forces.

[0031] In some optional embodiments, the chuck 6 includes an arc-shaped seat 61, a clamping jaw 62, a push rod 63 and a locking nut 64. The arc-shaped seat 61 has a first strip hole 611 and a second strip hole 612 on both sides along the circumference. The clamping jaw 62 is located in the arc-shaped seat 61. The clamping jaw 62 has a screw passing through the first strip hole 611. The screw is adapted to be connected to the locking nut 64 outside the arc-shaped seat 61. After the push rod 63 passes through the second strip hole 612, it can tighten the skin 300 located in the clamping jaw 62.

[0032] In this embodiment, the first strip hole 611 is provided on the arc seat 61, passing through the side wall of the arc seat 61, and the screw passes through the hole to connect with the clamping jaw 62. In an alternative embodiment, the first strip hole can also be provided on the clamping jaw 62. Figure 4 When it is set on the arc seat 61, it is usually necessary to ensure that the outer wall of the arc seat 61 is an arc structure. When it is set on the clamping jaw 62, the outer wall of the arc seat 61 is not restricted, for example, it is a polygonal structure. The arc seat only needs to open a through hole through the side wall to allow the screw to pass through.

[0033] In some optional embodiments, the clamping jaw 62 has a sliding rod passing through the second bar-shaped hole 612, the sliding rod has a through hole with an internal thread, the through hole is connected to the inner side of the clamping jaw 62, and the push rod 63 has an external thread adapted to pass through the through hole.

[0034] The above embodiment provides an implementation method of the chuck, that is, the push rod 63 is driven by a thread to achieve forward and backward movement. Figure 3 and Figure 4 The chuck 6 mainly includes an arc seat 61 and a clamping jaw 62. The arc seat 61 provides a slot between 90° and 180°. The clamping jaw 62 is installed in the slot and can rotate freely in the slot. There are two bar holes on both sides of the arc seat 61, such as Figure 3 As shown, the left side of the arc seat 61 is a second strip hole 612, which is mainly used to install the push rod 63. After the push rod 63 passes through the clamping jaw 62, it can tighten the skin inside the clamping jaw 62. In this embodiment, the push rod 63 is a screw with an external thread. Correspondingly, the clamping jaw 62 provides a through hole with an internal thread. The push rod 63 can be moved forward and backward in the through hole by rotating. Figure 4 As shown, the right side of the arc seat 61 is a first strip-shaped hole 611, which is mainly used to install a screw and cooperate with a lock nut 64 to realize the rotation of the clamping jaw 62. When the lock nut 64 is tightened, the clamping jaw 62 is fixed in the arc seat 61. When the lock nut 64 is loosened, the clamping jaw 62 can rotate freely in the arc seat 61. That is, tightening the lock nut 64 can lock the angle of the clamping jaw 62, and loosening the lock nut 64 can adjust the angle of the clamping jaw 62. In this embodiment, the rotation angle of the clamping jaw 62 is determined by the length of the first strip-shaped hole.

[0035] In this embodiment, the clamping jaw 62 is initially in a locked state and is locked in the slot of the arc seat 61 and cannot rotate. After adjusting the telescopic rod of the clamping device so that the clamping jaw 62 at the end of the telescopic rod presses against the skin, the push rod 63 is rotated to press against the skin in the clamping jaw 62. Then, the locking nut 64 is loosened so that the clamping jaw 62 can rotate freely in the slot of the arc seat 61 to meet on-site use requirements.

[0036] In some optional embodiments, the clamping jaw 62 has a support frame 621 passing through the arc seat 61 , the support frame 621 has a through hole, the push rod 63 passes through the through hole and is connected to the rocker arm 631 , and the rocker arm 631 is hinged on the support frame 621 .

[0037] This embodiment provides another implementation of the chuck 6, in which the push rod 63 that originally moved in a threaded stepping manner is driven by a rocker arm 631, and the threaded push rod and the rocker arm push rod exist independently. Figure 5 A support frame 621 is provided, one end of the support frame 621 is connected to the clamping claw 62 through two connecting rods, and the other end of the support frame 621 is a cylindrical structure with a through hole. The push rod 63 can pass through the through hole. After the push rod 63 further passes through the clamping claw 62, the end extends into the clamping claw 62 to provide a top thrust on the skin. The other end of the push rod 63 is hinged with a right-angle rocker arm 631. Both sides of the rocker arm 631 are hinged to the cylindrical structure through a connecting rod. The push and pull of the push rod 63 is achieved by rotating the rocker arm 631. Figure 5 The push rod 63 is shown as being in a clamped state with the clamping jaws 62 extended therein. After the rocker arm 631 is rotated downward, the push rod 63 is pulled back, so that the push rod 63 is converted from the clamped state to the relaxed state. This embodiment realizes the rapid clamping function of the clamping jaws.

[0038] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A multi-dimensional sensing mirror milling force digital fast clamping device, characterized in that: It comprises a support frame (200) and a plurality of clamping mechanisms (100) fixed on the support frame (200), each clamping mechanism (100) comprising a first telescopic rod (2), a second telescopic rod (7) and a clamping head (6); One end of the first telescopic rod (2) and one end of the second telescopic rod (7) are respectively hinged to two support points of the support frame (200) through a ball joint (1); the other end of the first telescopic rod (2) and the other end of the second telescopic rod (7) are hinged to each other; a clamp (6) is arranged in front of one end where the first telescopic rod (2) and the second telescopic rod (7) are hinged to each other, and a three-axis sensor (5) is arranged between the clamp and the hinge end; the clamp (6) of each clamping mechanism (100) is used to clamp the skin (300) at multiple locations on both sides of the skin (300); The chuck (6) comprises an arc seat (61), a clamping jaw (62), a push rod (63) and a locking nut (64); the arc seat (61) has a first strip hole (611) and a second strip hole (612) on both sides along the circumference; the clamping jaw (62) is located in the arc seat (61); the clamping jaw (62) has a screw passing through the first strip hole (611); the screw is adapted to connect the locking nut (64) outside the arc seat (61); after the push rod (63) passes through the second strip hole (612), it can tighten the skin (300) located in the clamping jaw (62); The clamping jaw (62) has a sliding rod passing through the second strip-shaped hole (612), the sliding rod has a through hole with an internal thread, the through hole is connected to the inner side of the clamping jaw (62), and the push rod (63) has an external thread adapted to pass through the through hole; The clamping jaw (62) has a support frame (621) passing through the arc seat (61), the support frame (621) has a through hole, the push rod (63) passes through the through hole and is connected to the rocker arm (631), and the rocker arm (631) is hinged on the support frame (621).

2. The multi-dimensional sensing mirror milling force digital quick clamping device according to claim 1, characterized in that: The first telescopic rod (2) and the second telescopic rod (7) are three-stage or more telescopic rods, and the telescopic rods of adjacent stages are locked by a cam shaft (3). The outer surface of the telescopic rod is provided with a protective sleeve (4) made of a corrugated tube.

3. The multi-dimensional sensing mirror milling force digital quick clamping device according to claim 1 is characterized in that: The three-axis sensor (5) adopts a resistance strain sensor.

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