An assembly stand with stress monitoring and adjustment function

Abstract

The present application belongs to the field of assembly of aeronautical manufacturing engineering, and relates to an assembly jig with stress monitoring and adjusting functions. The present application extends the size control of aircraft assembly to the coupling control of size and stress, realizes real-time monitoring and adjusting of assembly stress, reduces or even eliminates assembly stress, and further improves the assembly quality of products. The presser is replaced by a wall plate adjusting unit at a key position, one-way press adjusting is extended to two-way tension and press adjusting, and the flexibility of wall plate adjusting is enhanced. The proposed assembly jig with stress monitoring and adjusting functions is improved on the basis of a traditional assembly jig, and effectively controls the design, manufacturing and use costs. The mechanical interfaces of the designed numerical control positioning unit, intersection measuring unit and wall plate adjusting unit with the basic structure are the same as those of a single-point positioner, intersection positioner and presser, respectively, and the system complexity can be avoided by reasonable arrangement according to the assembly quality requirements.

Description

Technical Field

[0001] This invention belongs to the assembly field of aerospace manufacturing engineering, and relates to an assembly jig with stress monitoring and adjustment functions. The related technology of the assembly jig with stress monitoring and adjustment functions can also be applied to the assembly tooling of other components. Background Technology

[0002] In traditional aircraft assembly, process control primarily focuses on dimensional control, typically using methods like pin tightness to qualitatively assess assembly stress. However, with the widespread use of composite materials and increasingly stringent aircraft performance requirements, the impact of assembly stress on product quality cannot be ignored. Therefore, in addition to dimensional control, aircraft assembly processes must also consider stress control. Currently, aircraft sub-assembly faces challenges such as weak part consistency, complex assembly processes, and the inability to quantitatively measure assembly stress. Traditional aircraft assembly jigs are primarily purely mechanical structures, mainly composed of basic frame beams, locators, jigs, clamps, and panel clamps. They have low levels of electrification and can generally only be adjusted through design and process compensation.

[0003] Chengdu Aircraft Industry (Group) Co., Ltd. has proposed a modular airfoil assembly tooling, CN118220519A. This tooling adopts a modular design concept, featuring multiple basic units. It achieves reconfigurability through box-type connections, reducing the design and manufacturing costs of airfoil tooling and decreasing tooling preparation time. However, this tooling is a purely mechanical structure and lacks the ability to automatically monitor and adjust assembly stress.

[0004] The Beijing Great Wall Aviation Measurement and Control Technology Research Institute of the Aviation Industry Corporation of China (AVIC) has proposed an adjustable, weakly rigid, conformal tooling for large components and a support method for aircraft cylindrical sections (CN112660412A). The support module of this tooling has position and angle adjustment functions. The position and attitude of the support module are adjusted by detecting the deformation of the cylindrical section using measuring equipment, thereby compensating for the deformation of the cylindrical part and reducing assembly stress. However, this method is mainly manual, with a low degree of automation, and the equipment and related technologies are highly specialized, making it difficult to apply to the assembly of other aircraft components.

[0005] Xi'an Aircraft Industry Group Co., Ltd. of AVIC has proposed an adaptive micro-adjustment mechanism and method for aircraft wing box sections (CN115924105A). This device consists of an adaptive docking device, horizontal and vertical adjustment devices, and force sensors. During wing box assembly, the force sensors can determine the stress state of the wing box, and the horizontal and vertical adjustment devices can reduce the stress. However, this device is generally used for overall attitude adjustment of the wing box to facilitate the docking of large aircraft components, and it cannot monitor and adjust assembly stress during the assembly process of the wing box itself.

[0006] Shortcomings of existing inventions:

[0007] (1) The traditional assembly jigs currently used do not have the ability to monitor stress state and cannot adjust assembly stress through means other than design and process compensation.

[0008] (2) At present, equipment for compensating for deformation or stress of weak rigid large components generally adopts a purely mechanical structure, relies mainly on manual operation, has a low degree of automation, and is difficult to achieve precise adjustment.

[0009] (3) At present, equipment with stress monitoring and adjustment functions is used in assembly scenarios such as large component assembly and wing assembly. However, due to the limitations of equipment size and technology, the relevant technology has not yet been promoted to the aircraft assembly stage.

[0010] (4) The stress monitoring and adjustment equipment currently used is generally used in assembly processes such as fuselage assembly, and the complexity of the monitoring and adjustment system is relatively low. However, there are many components to be processed in the sub-assembly process, and the assembly process and manufacturing cost must be considered. The complexity of the monitoring system cannot be too high, and there is currently no relevant solution. Summary of the Invention

[0011] This invention proposes an assembly frame with stress monitoring and adjustment functions.

[0012] The proposed assembly jig is an improvement upon the traditional assembly jig, in which accessories such as single-point locators, intersection locators, and clamps are the basic units. In the proposed jig, the single-point locators, intersection locators, and clamps are replaced with modules possessing measurement and adjustment functions, such as CNC positioning units, intersection measurement units, and panel adjustment units. During assembly, for areas requiring monitoring of assembly stress, the single-point locators, intersection locators, and clamps are replaced with CNC positioning units, intersection measurement units, and panel adjustment units, respectively, improving the monitoring and adjustment capabilities of the assembly process. In non-critical areas, traditional single-point locators, intersection locators, and clamps are still used to avoid excessive system complexity.

[0013] The proposed assembly frame with stress monitoring and adjustment functions can be divided into a basic structure, a CNC positioning unit, an intersection measurement unit, and a wall panel adjustment unit, based on its structural characteristics.

[0014] The basic structure consists of traditional prefabricated frame components, including frame beams, single-point locators, intersection locators, clamps, and other accessories such as drill jigs and clamping plates. The frame beams are assembled using welding and screws, while the single-point locators, intersection locators, clamps, and other accessories such as drill jigs and clamping plates are installed on the frame beams using screws and pins.

[0015] The CNC positioning unit is a three-axis slide with high positioning accuracy, composed of three stacked single-axis slides, with the three motion axes of the three-axis slides perpendicular to each other. An end positioner is installed at the end of the CNC positioning unit; one end of the end positioner connects to the positioning point of the product, and the other end connects to a three-dimensional force sensor on the CNC positioning unit via screws and pins. The three-dimensional force sensor is used to measure the stress at the positioning point. Each single-axis slide of the CNC positioning unit uses a ball screw and linear guide as its transmission mechanism. Each linear guide is equipped with a guide clamp to maintain the position of each motion axis. A servo motor provides power to each single-axis slide via a precision reducer. The servo motor has a braking function and integrates a high-precision encoder. Each single-axis slide of the CNC positioning unit is equipped with a grating ruler to achieve precise displacement control of each motion axis.

[0016] The intersection measurement unit consists of an additional six-dimensional force sensor added to the existing intersection locator for real-time monitoring of triaxial forces and torques at critical intersection points. The intersection measurement unit is not adjustable. It comprises a base A, a screw-in nut, a screw-in rod A, a sensor mounting base, a six-dimensional force sensor, a sensor adapter, and a locator. Base A is mounted to the foundation structure with screws. The screw-in rod A engages with the screw-in nut on base A; rotating the screw-in nut moves the screw-in rod A along its axial direction. The inner hole of the sensor mounting base mates with the end shaft of the screw-in rod A and is secured with a pin. The outer surface of the six-dimensional force sensor is positioned with the sensor mounting base via a stop, and the six-dimensional force sensor is mounted on the sensor mounting base with screws. The concave hole on the measuring surface of the six-dimensional force sensor mates with the boss at one end of the sensor adapter, and the sensor adapter is mounted on the six-dimensional force sensor using pins and screws. The shaft at the other end of the sensor adapter mates with the inner hole of the locator and is secured with a pin.

[0017] The wall panel adjustment unit is used to press and tighten the composite wall panel and monitor the pressure or tension applied during the pressing and tightening process. The wall panel adjustment unit consists of a vacuum suction cup, a mounting cover plate, a suction cup mounting seat, an adapter flange, a tension / compression sensor, a ball socket seat, a ball socket cover plate, a screw B, and a base B. The base B is mounted on the foundation structure with screws. The screw B mates with the threaded hole in the base B. The end of the screw B is spherical and is installed in the ball socket of the ball socket seat. The ball socket cover plate is mounted on one end of the ball socket seat with screws, encapsulating the screw B within the ball socket seat. The other end of the ball socket seat has a stop that mates with the outer surface of the tension / compression sensor, and the sensor is secured to the ball socket seat with screws. One end of the adapter flange has a boss that mates with a recess on the tension / compression sensor and is fixed to the sensor with screws. The adapter flange and the suction cup mounting seat are positioned by a stop and connected by screws. The vacuum suction cup is locked to the mounting cover plate with a nut, and the mounting cover plate is installed onto the suction cup mounting base with screws. In assembly operations, multiple sets of wall panel adjustment units are generally combined into an array to more precisely control the wall panel shape and assembly stress.

[0018] According to one aspect of this application, an assembly frame with stress monitoring and adjustment functions is provided, which consists of a base structure 100, a CNC positioning unit 200, an intersection measurement unit 300, and a wall panel adjustment unit 400.

[0019] The basic structure 100 includes a frame beam structure 101, a single-point locator 102, an intersection locator 103, a clamping device 104, a drilling jig, a clamping plate, and other accessories 105.

[0020] The frame beam structure 101 is constructed using welding, screw connection, and pin connection methods.

[0021] The single-point locator 102, intersection locator 103, and clamping device 104 can be used for non-critical parts that do not require stress monitoring or adjustment.

[0022] The CNC positioning unit 200, intersection measurement unit 300, and wall panel adjustment unit 400 have the same mechanical interface as the single-point positioner 102, intersection positioner 103, and clamping device 104, respectively, and can be flexibly configured according to requirements.

[0023] The CNC positioning unit 200 mainly realizes the positioning of key parts of the product that require stress monitoring and adjustment;

[0024] The basic configuration of the CNC positioning unit 200 is a three-axis slide table, in which the three motion axes of the three-axis slide table are perpendicular to each other and are formed by stacking three single-axis slide tables.

[0025] The numerical control positioning unit 200 includes an end positioner 201, a three-dimensional force sensor 202, an end slide 203, a guide rail clamp 204, a ball screw 205, a linear guide rail 206, a precision reducer 207, a servo motor 208, and a grating ruler 209.

[0026] One side of the end positioner 201 is fixed to the three-dimensional force sensor 202 by screws and pins, and the other end is connected to the positioning hole on the product by a pin. During the assembly operation, the CNC positioning unit 200 can monitor the stress value at the connection positioning point and can finely adjust the position of the end positioner 201 within the tolerance range to release assembly stress.

[0027] A three-dimensional force sensor 202 is installed on the end slide 203 of the CNC positioning unit 200 to monitor the stress at the positioning point. This stress is used as one of the inputs for assembly stress evaluation. The adjustment range of the CNC positioning unit 200 is limited by the measured stress value to avoid over-adjustment and damage to the product.

[0028] The transmission mechanism of each single-axis slide of the CNC positioning unit 200 adopts ball screw 205 and linear guide 206. Each linear guide 206 is equipped with a guide clamp 204 to realize the position holding of each motion axis of the CNC positioning unit 200.

[0029] Each motion axis uses a servo motor 208 as the power source via a precision reducer 207. The servo motor 208 has a brake function and integrates a high-precision encoder.

[0030] Each single-axis slide is equipped with a set of grating rulers 209 to achieve position control of each motion axis.

[0031] The intersection measurement unit 300 includes a base A301, a screw-in nut 302, a screw-in screw A303, a sensor mounting base 304, a six-dimensional force sensor 305, a sensor adapter 306, and a positioner 307.

[0032] The intersection measurement unit 300 is used for stress monitoring at important intersections that have a significant impact on assembly quality. It can monitor the triaxial force and the torque around the triaxial force at the intersection. The intersection measurement unit 300 does not have adjustment capability.

[0033] The base A301 is mounted on the base structure 100 by screws, and the screw-in nut 302 is mounted on the base A301 by a sliding groove. The screw-in rod A303 is engaged with the threaded hole of the screw-in nut 302. By rotating the screw-in nut 302, the screw-in rod A303 can be moved along its own axis.

[0034] The inner hole of the sensor mounting base 304 mates with the end shaft section of the screw A303 and is fastened by a pin;

[0035] The outer cylindrical surface of the six-dimensional force sensor 305 is positioned with the sensor mounting base 304 by a stop, and the six-dimensional force sensor 305 is fastened to the sensor mounting base 304 by screws.

[0036] The end boss of the sensor adapter 306 engages with the recessed hole on the measuring surface of the six-dimensional force sensor 305, and the sensor adapter 306 is fastened to the six-dimensional force sensor 305 by pins and screws.

[0037] The inner hole of the positioner 307 mates with one end of the shaft of the sensor adapter 306, and is positioned and fastened by a pin.

[0038] The wall panel adjustment unit 400 is used to press or tighten the composite wall panel;

[0039] The wall panel adjustment unit 400 includes a vacuum suction cup 401, a mounting cover plate 402, a suction cup mounting seat 403, an adapter flange 404, a tension / compression sensor 405, a ball socket seat 406, a ball socket cover plate 407, a screw B408, and a base B409.

[0040] The base B409 is mounted on the base structure 100 by screws;

[0041] The screw B408 engages with the threaded hole on the base B409. The end of the screw B408 is spherical and is installed in the ball socket 406.

[0042] The ball socket cover plate 407 is installed at one end of the ball socket seat 406 by screws, and the spherical end of the screw B408 is encapsulated inside the ball socket seat 406.

[0043] The tension / compression sensor 405 is positioned at the end of the ball socket 406 by a stop, and the tension / compression sensor 405 is fixed on the ball socket 406 with screws;

[0044] The boss at one end of the adapter flange 404 mates with the recessed hole on the tension / compression sensor 405 and is connected to the tension / compression sensor 405 by screws.

[0045] The suction cup mounting base 403 and the adapter flange 404 are positioned by a stop and fastened by screws;

[0046] The end of the vacuum suction cup 401 is locked onto the mounting cover plate 402 by a nut, and the mounting cover plate 402 is installed on one side of the suction cup mounting base 403 by screws.

[0047] The suction cup mounting base 403 has a certain space inside to provide a buffer stroke for the vacuum suction cup 401;

[0048] During the assembly process, multiple sets of wall panel adjustment units 400 are constructed into an array to achieve precise adjustment of the deformation and stress of the composite wall panel;

[0049] During the assembly process, the vacuum generator is driven by the high-pressure air source in the factory to extract the air from the vacuum suction cup 401, and the vacuum suction cup 401 is controlled by the solenoid valve to attract the composite wall panel.

[0050] It also includes electrical control systems;

[0051] The electrical control system includes a servo driver, an industrial data acquisition card, a PLC controller, an industrial switch, and an industrial computer. All components communicate with each other via the Internet or an EtherCAT bus.

[0052] The beneficial effects of this invention are:

[0053] (1) Extend aircraft assembly from size control to coupled control of size and stress, realize real-time monitoring and adjustment of assembly stress, reduce or even eliminate assembly stress, and thus improve product assembly quality.

[0054] (2) The single-point positioner at the key positioning point is replaced with a CNC positioning unit to realize stress monitoring and position fine adjustment of the positioning point. The CNC positioning unit has a large stroke range of three motion axes and has a certain degree of flexibility.

[0055] (3) Replace the clamping device with the wall panel adjustment unit at key locations to extend the unidirectional clamping adjustment to bidirectional tensioning and clamping adjustment, thereby enhancing the flexibility of wall panel adjustment.

[0056] (5) The proposed assembly jig with stress monitoring and adjustment function is an improvement on the traditional assembly jig, which effectively controls the design, manufacturing and use costs.

[0057] (6) The mechanical interfaces of the designed CNC positioning unit, intersection measurement unit and wall panel adjustment unit with the basic structure are the same as those of the single point positioner, intersection positioner and clamping device, respectively. They can be reasonably arranged according to the assembly quality requirements to avoid excessive system complexity. Attached Figure Description

[0058] Figure 1 This is a schematic diagram of an assembly frame with stress monitoring and adjustment functions.

[0059] Figure 2 A partially enlarged diagram (I) shows the assembly frame with stress monitoring and adjustment functions.

[0060] Figure 3 Partial enlarged view II of the assembly frame composition diagram with stress monitoring and adjustment functions.

[0061] Figure 4 This is a schematic diagram of the CNC positioner unit structure.

[0062] Figure 5 This is a schematic diagram of the intersection measurement unit.

[0063] Figure 6 This is a schematic diagram of the intersection measurement unit structure.

[0064] Figure 7 This is a schematic diagram of the wall panel adjustment unit.

[0065] Figure 8 This is a schematic cross-sectional view of the wall panel adjustment unit.

[0066] Figure 9 This is a schematic diagram of the wall panel adjustment unit array.

[0067] Figure 10 This is a schematic diagram of a single-point locator.

[0068] Figure 11 This is a schematic diagram of the intersection locator structure.

[0069] Figure 12 This is a schematic diagram of the clamping device structure.

[0070] Figure 13 This is a diagram of the electrical control system for an assembly frame with stress monitoring and adjustment functions.

[0071] Figure 14 This is a flowchart of the assembly jig process with stress monitoring and adjustment functions.

[0072] The components include: 100 basic structure, 200 CNC positioning unit, 300 intersection measurement unit, 400 wall panel adjustment unit, 101 frame beam structure, 102 single-point positioner, 103 intersection positioner, 104 clamping device, 105 drill jig and clamping plate and other accessories, 201 end positioner, 202 three-dimensional force sensor, 203 end slide, 204 guide rail clamp, 205 ball screw, 206 linear guide, and 207 precision reducer. 208 Servo Motor, 209 Grating Ruler, 301 Base A, 302 Screw-in Nut, 303 Screw-in Screw A, 304 Sensor Mounting Base, 305 Six-Dimensional Force Sensor, 306 Sensor Adapter, 307 Positioner, 401 Vacuum Suction Cup, 402 Mounting Cover, 403 Suction Cup Mounting Base, 404 Adapter Flange, 405 Tension / Compression Sensor, 406 Ball Mouth Seat, 407 Ball Mouth Cover, 408 Screw-in Screw B, 409 Base B. Detailed Implementation

[0073] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.

[0074] Example 1

[0075] Reference Figure 1 and Figure 3 The assembly frame with stress monitoring and adjustment functions is an improvement on the traditional assembly frame, and includes four parts: basic structure 100, CNC positioning unit 200, intersection measurement unit 300, and wall panel adjustment unit 400.

[0076] Reference Figure 1 , Figure 2 , Figure 10 , Figure 11 and Figure 12 The basic structure 100 includes a frame beam structure 101, a single-point locator 102, an intersection locator 103, a clamping device 104, and other accessories 105 such as a drill jig and a clamping plate. The frame beam structure 101 is constructed using welding, screw connections, and pin connections. The single-point locator 102, intersection locator 103, and clamping device 104 can be used for non-critical parts that do not require stress monitoring or adjustment. The CNC positioning unit 200, intersection measurement unit 300, and wall panel adjustment unit 400 have the same mechanical interfaces as the single-point locator 102, intersection locator 103, and clamping device 104, respectively, and can be flexibly configured according to requirements.

[0077] Reference Figure 4 The CNC positioning unit 200 primarily positions key parts of the product that require stress monitoring and adjustment. The basic configuration of the CNC positioning unit 200 is a three-axis slide, with its three motion axes perpendicular to each other, formed by stacking three single-axis slides. During assembly, the CNC positioning unit 200 can monitor the stress value at the connected positioning point and fine-tune the position of the end positioner 201 within a tolerance range to release assembly stress. A three-dimensional force sensor 202 is installed on the end slide 203 of the CNC positioning unit 200 to monitor the stress at the positioning point, serving as one of the inputs for assembly stress evaluation. The measured stress value limits the adjustment range of the CNC positioning unit 200, preventing over-adjustment and damage to the product. One side of the end positioner 201 is fixed to the three-dimensional force sensor 202 with screws and pins, while the other end is connected to the positioning hole on the product via a pin. The transmission mechanism of each single-axis slide of the CNC positioning unit 200 adopts a ball screw 205 and a linear guide 206. Each linear guide 206 is equipped with a guide clamp 204 to maintain the position of each motion axis of the CNC positioning unit 200. Each motion axis uses a servo motor 208 as its power source through a precision reducer 207. The servo motor 208 has a braking function and integrates a high-precision encoder. Each single-axis slide is equipped with a set of grating rulers 209 to achieve position control of each motion axis.

[0078] Reference Figure 5 and Figure 6The intersection measurement unit 300 is used for stress monitoring at important intersections that significantly affect assembly quality. It can monitor the triaxial force and triaxial torque at the intersection. The intersection measurement unit 300 is not adjustable. The intersection measurement unit 300 mainly consists of a base A301, a screw-in nut 302, a screw-in rod A303, a sensor mounting base 304, a six-dimensional force sensor 305, a sensor adapter 306, and a positioner 307. The base A301 is mounted on the base structure 100 with screws. The screw-in nut 302 is mounted on the base A301 via a sliding groove. The screw-in rod A303 engages with the threaded hole of the screw-in nut 302. Rotating the screw-in nut 302 allows the screw-in rod A303 to move along its own axis. The inner hole of the sensor mounting base 304 engages with the end shaft of the screw-in rod A303 and is secured with a pin. The outer cylindrical surface of the six-dimensional force sensor 305 is positioned against the sensor mounting base 304 using a stop, and the six-dimensional force sensor 305 is fastened to the sensor mounting base 304 with screws. The end boss of the sensor adapter 306 mates with the recessed hole on the measuring surface of the six-dimensional force sensor 305, and the sensor adapter 306 is fastened to the six-dimensional force sensor 305 using pins and screws. The inner hole of the positioner 307 mates with one end shaft section of the sensor adapter 306, and is positioned and fastened using pins.

[0079] Reference Figure 7 , Figure 8 and Figure 9The wall panel adjustment unit 400 is used to press or tighten the composite wall panel. The wall panel adjustment unit 400 mainly consists of a vacuum suction cup 401, a mounting cover plate 402, a suction cup mounting base 403, an adapter flange 404, a tension / compression sensor 405, a ball socket seat 406, a ball socket cover plate 407, a screw-in screw B408, and a base B409. The base B409 is mounted on the base structure 100 with screws. The screw-in screw B408 mates with a threaded hole on the base B409, and its end is spherical, installed in the ball socket seat 406. The ball socket cover plate 407 is mounted on one end of the ball socket seat 406 with screws, encapsulating the spherical end of the screw-in screw B408 inside the ball socket seat 406. The tension / compression sensor 405 is positioned at the end of the ball socket seat 406 via a stop, and is fixed to the ball socket seat 406 with screws. One end of the adapter flange 404 has a boss that mates with a recessed hole in the tension / compression sensor 405, and is connected to the tension / compression sensor 405 by screws. The suction cup mounting base 403 and the adapter flange 404 are positioned using a stop joint and secured with screws. The end of the vacuum suction cup 401 is locked to the mounting cover plate 402 by a nut, and the mounting cover plate 402 is installed on one side of the suction cup mounting base 403 by screws. A certain amount of space is provided inside the suction cup mounting base 403 to allow for a buffer stroke for the vacuum suction cup 401. During assembly, multiple sets of wall panel adjustment units 400 are arranged in an array to achieve precise adjustment of the deformation and stress of the composite wall panel. During assembly, a vacuum generator driven by a high-pressure air source in the plant is used to extract air from the vacuum suction cup 401, and a solenoid valve controls the suction of the vacuum suction cup 401 onto the composite wall panel.

[0080] Reference Figure 13 The assembly frame with stress monitoring and adjustment functions has an electrical control system comprising servo drivers, industrial data acquisition cards, PLC controllers, industrial switches, and industrial PCs. These components communicate via the Internet or EtherCAT bus. Each servo motor 208 and linear encoder 209 of the single-axis slide in the CNC positioning unit 200 is connected to a servo driver, and multiple servo drivers are controlled by PLC-1. PLC-1 is connected to the industrial PC via an industrial switch. PLC-2 controls the solenoid valves to achieve the adsorption and release of the vacuum suction cups 401 on the wall panel adjustment unit 400, and is also connected to the industrial PC via an industrial switch. A six-dimensional force sensor 305, a three-dimensional force sensor 202, and a tension / compression sensor 405 are connected to the industrial PC via data acquisition cards.

[0081] Reference Figure 14The workflow of the assembly jig with stress monitoring and adjustment functions is as follows: After the assembly operation begins, the electrical system of the assembly jig is activated and a self-test is initiated. The CNC positioning unit 200, intersection measurement unit 300, and wall panel adjustment unit 400 are in their theoretical positions and initial states. After the self-test confirms there are no problems, the assembly operation begins according to the assembly process specifications. When assembling parts requiring precise stress control, the three-dimensional force sensor 202, six-dimensional force sensor 305, and tension / compression sensor 405 transmit the measured values ​​to the industrial control computer. After calculation, the industrial control computer determines whether the stress meets the quality requirements. If not, the CNC positioning unit 200 makes fine adjustments within the tolerance range and rotates the screw B408 of the wall panel adjustment unit 400 until the assembly stress meets the standard. After completing the assembly of all components according to this process, the assembly operation ends.

[0082] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions made by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An assembly frame with stress monitoring and adjustment functions, characterized in that, It consists of a basic structure (100), a CNC positioning unit (200), an intersection measurement unit (300), and a wall panel adjustment unit (400); The basic structure (100) includes a frame beam structure (101), a single-point locator (102), an intersection locator (103), a clamping device (104), a drill jig, and a clamping plate (105). The single-point locator (102), intersection locator (103), and clamping device (104) are used for non-critical parts that do not require stress monitoring or adjustment. The numerical control positioning unit (200) and the single-point positioner (102) have the same mechanical interface and can be flexibly configured according to requirements; The intersection measurement unit (300) and the intersection locator (103) have the same mechanical interface and can be flexibly configured according to requirements; The wall panel adjustment unit (400) and the clamping device (104) have the same mechanical interface and can be flexibly configured according to requirements; The CNC positioning unit (200), intersection measuring unit (300), wall panel adjusting unit (400), single point locator (102), intersection locator (103) and clamping device (104) are connected to the frame beam structure (101); The numerical control positioning unit (200) mainly realizes the positioning of key parts of the product that require stress monitoring and adjustment; The basic configuration of the numerical control positioning unit (200) is a three-axis slide table. The three motion axes that make up the three-axis slide table are perpendicular to each other and are formed by stacking three single-axis slide tables. The numerical control positioning unit (200) includes an end positioner (201), a three-dimensional force sensor (202), an end slide (203), a guide rail clamp (204), a ball screw (205), a linear guide rail (206), a precision reducer (207), a servo motor (208), and a grating ruler (209). One side of the end positioner (201) is fixed to the three-dimensional force sensor (202) by screws and pins, and the other end is connected to the positioning hole on the product by a pin. During the assembly operation, the CNC positioning unit (200) monitors the stress value at the connection positioning point and finely adjusts the position of the end positioner (201) within the tolerance range to release the assembly stress. A three-dimensional force sensor (202) is installed on the end slide (203) of the CNC positioning unit (200) to monitor the stress at the positioning point. The stress is used as one of the input parameters for assembly stress evaluation. The adjustment range of the CNC positioning unit (200) is limited by the measured stress value to avoid over-adjustment and damage to the product. The transmission mechanism of each single-axis slide of the CNC positioning unit (200) adopts ball screw (205) and linear guide (206). Each linear guide (206) is equipped with a guide clamp (204) to realize the position holding of each motion axis of the CNC positioning unit (200). Each motion axis uses a servo motor (208) as the power source via a precision reducer (207). The servo motor (208) has a brake function and integrates a high-precision encoder. Each single-axis slide is equipped with a set of grating rulers (209) to realize the position control of each motion axis; The intersection measurement unit (300) includes a base A (301), a screw-in nut (302), a screw-in screw A (303), a sensor mounting base (304), a six-dimensional force sensor (305), a sensor adapter (306), and a positioner (307). The intersection measurement unit (300) is used for stress monitoring at important intersections that have a significant impact on assembly quality. It can monitor the triaxial force and the torque around the triaxial force at the intersection. The intersection measurement unit (300) does not have adjustment capability. The base A (301) is mounted on the base structure (100) by screws, and the screw-in nut (302) is mounted on the base A (301) by a sliding groove. The screw-in rod A (303) is engaged with the threaded hole of the screw-in nut (302). By rotating the screw-in nut (302), the screw-in rod A (303) can move along its own axis. The inner hole of the sensor mounting base (304) is engaged with the end shaft section of the screw A (303) and fastened by a pin; The outer cylindrical surface of the six-dimensional force sensor (305) is positioned with a stop between it and the sensor mounting base (304), and the six-dimensional force sensor (305) is fastened to the sensor mounting base (304) by screws; The end boss of the sensor adapter (306) engages with the recessed hole on the measuring surface of the six-dimensional force sensor (305), and the sensor adapter (306) is fastened to the six-dimensional force sensor (305) by pins and screws. The inner hole of the positioner (307) mates with one end of the shaft of the sensor adapter (306) and is positioned and fastened by a pin; The wall panel adjustment unit (400) is used to press or tighten the composite wall panel; The wall panel adjustment unit (400) includes a vacuum suction cup (401), a mounting cover plate (402), a suction cup mounting seat (403), a transition flange (404), a tension / compression sensor (405), a ball socket seat (406), a ball socket cover plate (407), a screw B (408), and a base B (409). The base B (409) is mounted on the base structure (100) by screws; The screw B (408) engages with the threaded hole on the base B (409), and the end of the screw B (408) is spherical and is installed in the ball socket (406); The ball socket cover plate (407) is installed at one end of the ball socket seat (406) by screws, and the spherical end of the screw B (408) is encapsulated inside the ball socket seat (406); The tension / compression sensor (405) is positioned at the end of the ball socket (406) through a stop, and the tension / compression sensor (405) is fixed to the ball socket (406) with screws; The adapter flange (404) has a boss at one end that mates with a recessed hole on the tension / compression sensor (405) and is connected to the tension / compression sensor (405) by screws; The suction cup mounting base (403) and the adapter flange (404) are positioned by a stop and fastened by screws; The end of the vacuum suction cup (401) is locked to the mounting cover plate (402) by a nut, and the mounting cover plate (402) is installed on one side of the suction cup mounting base (403) by screws; The suction cup mounting base (403) has a certain space inside to provide a buffer stroke for the vacuum suction cup (401); In the assembly process, multiple sets of wall panel adjustment units (400) are arranged in an array to achieve precise adjustment of the deformation and stress of the composite wall panel; During the assembly process, the vacuum generator is driven by the high-pressure air source in the factory to extract the air from the vacuum suction cup (401), and the vacuum suction cup (401) is controlled by the solenoid valve to adhere to the composite wall panel.

2. The assembly frame with stress monitoring and adjustment function according to claim 1, characterized in that, It also includes electrical control systems; The electrical control system includes a servo driver, an industrial data acquisition card, a PLC controller, an industrial switch, and an industrial computer. All components communicate with each other via the Internet or an EtherCAT bus.

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