A measuring and positioning tool for a magnetic shielding panel

Abstract

The application provides a kind of magnetic shielding panel measurement positioning tool, including installation on the profile between magnetic shielding panel tool base, tool base includes reference seat and can be detachedly connected on the measurement component above reference seat;The bottom of reference seat is provided with the plug-in part, and the plug-in part is matched with the rebate of profile to form the measurement reference;The measurement component includes vertical column and the spacing measurement piece symmetrically arranged on the two sides of column;Spacing measurement piece can slide along the height direction of column, and its measurement end extends to the upper surface of magnetic shielding panel.This scheme forms stable measurement reference by the gap cooperation of the plug-in part on the bottom of tool base and the rebate of profile, and realizes accurate positioning by combining with the double-side spacing measurement piece symmetrically arranged on vertical column.The height of spacing measurement piece can be adjusted longitudinally, so that it extends to the upper surface of panel, and the influence of installation inclination angle is eliminated through adaptive structure, which significantly reduces the operation difficulty of construction personnel while ensuring accuracy, and solves the core defects of insufficient adaptability of prior art to complex working conditions.

Description

Technical Field

[0001] This invention relates to the field of measurement and positioning fixture technology, and in particular to a measurement and positioning fixture for a magnetically shielded panel. Background Technology

[0002] In the construction of magnetic shielding structures for large facilities such as large low-magnetic spaces, the installation accuracy of permalloy panels directly affects the magnetic field shielding effectiveness. Traditional construction methods, which rely on manual visual inspection combined with simple measuring tools for positioning, have systemic drawbacks: construction workers need to repeatedly adjust the panel position, visually observe the alignment of the panel edges with reference marks, and use steel rulers or tape measures to measure distances. This method depends on the experience of the construction workers and is particularly inefficient in curved surface installation scenarios (such as reactor domes). Actual measurement data shows that the average adjustment time for a single panel exceeds 5 minutes, and the final positioning error rate is relatively high, making it difficult to meet the installation requirements of high-precision magnetic shielding structures.

[0003] To address the aforementioned issues, existing solutions, such as the "Distance Measuring Device and Method for Power Grid Planning" disclosed in Chinese patent literature (publication number CN117006370A), include a distance measuring device and a mounting base installed at its bottom. It also includes a connecting platform installed below the mounting base. The connecting platform has two sets of symmetrically arranged snap-fit ​​structures for limiting the position of the mounting base. Below the connecting platform is an angle adjustment component for rotating the distance measuring device. Below the base plate is a height adjustment component for vertically adjusting the distance measuring device. The height adjustment component is movably connected to a housing for storing the distance measuring device. Another improved solution uses a laser distance measuring instrument, which achieves non-contact measurement, but requires manual calculation of spatial coordinates, resulting in a complex operation process and the inability to provide real-time feedback on positional deviations.

[0004] In summary, while the above solutions simplify the inspection process and reduce the calculation of cumulative data, several problems remain unresolved. Firstly, using traditional vernier calipers for measurement and installation requires repeated readings on both sides to adjust the spacing, leading to delays, inefficiency, and decreased focus due to repetitive operations. Secondly, since not all panels are installed horizontally, some are angled, and manual measurement is prone to errors in judging the contact state between the measuring element and the panel, potentially resulting in measurements being taken and installation completed before the measuring element is properly aligned with the panel. Thirdly, for outdoor construction involving magnetic shielding panel installation, the metal panels are susceptible to thermal expansion due to ambient temperature, causing measurement benchmark drift and resulting in errors that affect construction quality. These problems remain unresolved and represent significant pain points in the industry. Summary of the Invention

[0005] The primary objective of this invention is to address the measurement errors and low efficiency caused by tilt angle changes during the installation of magnetic shielding panels. By using the small gap between the bottom insertion part of the tooling base and the tongue and groove of the profile to form a fixed measurement benchmark, and combining this with the spacing measuring parts symmetrically arranged on both sides of the vertical column that can slide along the height and extend to the upper surface of the panel, tilt angle-independent direct reading distance positioning can be achieved, thereby eliminating the influence of installation tilt angle and improving installation accuracy and construction efficiency.

[0006] The second objective of this invention is to address the lack of non-contact high-precision positioning and real-time feedback in large magnetic shielding facilities. By generating dual-wavelength moiré fringes using a laser projection module and combining them with differential signal processing from a photoelectric detector, the invention enables the detection of edge displacement of the magnetic shielding panel and graded audio-visual prompts, thereby avoiding damage to the coating and reducing human error. At the same time, it improves detection efficiency and delays work fatigue.

[0007] The third objective of this invention is to solve the problem of reference drift caused by the thermal expansion of metal under diurnal temperature difference, and to maintain the stability of the measurement reference through the phase change compensation mechanism of the thermal expansion layer of the reference base.

[0008] The fourth objective of this invention is to solve the problem of misjudgment of contact status caused by uneven panel surface. It achieves visual guidance of abnormal local contact force by using the pressure sensing unit at the end of the spacing measuring device and the zone color display system.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] A measuring and positioning fixture for a magnetic shielding panel includes a fixture base mounted on a profile between the magnetic shielding panels. The fixture base includes a reference base and a measuring component detachably connected above the reference base. The bottom of the reference base is provided with a plug-in portion, which engages with the tongue and groove joint of the profile to form a measuring reference. The measuring component includes a vertical column and spacing measuring elements symmetrically arranged on both sides of the column. The spacing measuring elements can slide along the height direction of the column, and their measuring ends extend to the upper surface of the magnetic shielding panel.

[0011] The tooling base proposed in this solution forms a physical reference by fitting the bottom of the reference base with the profile tongue and groove joint with a small gap, eliminating the reference drift problem caused by traditional manual visual inspection. The dual-sided spacing measuring components on the vertical column can slide along the height, with their measuring ends extending to the upper surface of the magnetic shielding panel for edge positioning, ensuring that the distance between the edge of the shielding panel and the measuring reference meets the preset standard. The symmetrically arranged measuring components can be independently slidable to accommodate panels with different tilt angles within a range of ±15 degrees, solving the interference problem of traditional vernier calipers when installed on concave / convex surfaces. The modular design of the reference base and measuring components allows for quick assembly and disassembly, adapting to operations in confined spaces. Actual measurements show that the single-board adjustment time is reduced from 5-10 minutes to within 3 minutes, while the installation accuracy is improved from ±3mm to ±1mm.

[0012] Preferably, the column and the base are fixedly connected by a connector; the plug has a downwardly extending pin; the cross-sectional profile of the pin matches the profile of the tongue and groove inner wall; the pin and the tongue and groove are fitted with a small clearance.

[0013] Preferably, the spacing measuring elements on both sides of the column can be adjusted independently; the spacing measuring element includes a measuring head assembly that matches the angle of the magnetic shielding panel.

[0014] Preferably, the measuring head assembly includes an adaptive contour ruler that can abut against the angle of the magnetic shielding panel and adjust the extension direction of the bottom measuring mark.

[0015] Preferably, a laser projection module is integrated at the top of the column; the laser projection module includes:

[0016] The red laser emitting unit and the blue laser emitting unit are arranged side by side;

[0017] A diffraction grating plate fixed in front of the transmitting unit;

[0018] The diffraction grating is configured to generate a group of red parallel stripes and a group of blue parallel stripes with the same spacing, so that the two stripe groups form an overlapping projection area at the edge of the magnetic shielding panel at a preset position.

[0019] Preferably, a cantilever bracket is fixed to the side wall of the column; a photodetector is installed at the end of the cantilever bracket, the optical axis of the photodetector is perpendicular to the mounting plane of the magnetic shielding panel, and the center of the lens of the photodetector is at the same height as the center of the overlapping projection area; the output end of the photodetector is connected to a prompting device through a signal processing circuit.

[0020] Preferably, the measuring end of the spacing measuring element is provided with a contact detection element; the contact detection element has a pressure sensing unit embedded inside; the contact surface of the pressure sensing unit can match the upper surface of the magnetic shielding panel.

[0021] Preferably, the contact detection element includes an annular color-developing groove arranged around the length of the spacing measuring element; the annular color-developing groove has a color-developing strip embedded in it; the color-developing strip includes a plurality of LED units arranged along the length direction; each LED unit is connected to the partition output terminal of the pressure sensing unit through an independent wire; the partition output terminal of the pressure sensing unit corresponds one-to-one with the position of the LED unit.

[0022] Preferably, the reference base includes a first base and a second base that can slide relative to each other; an adjusting screw is connected between the first base and the second base along the width direction; a locking member is provided across the first base and the second base for fixation; and a thermal expansion layer is detachably provided on any side wall of the reference base along the width direction.

[0023] Preferably, the base is provided with a mounting hole at the bottom, and a fastening bolt is installed in the mounting hole from bottom to top. The fastening bolt includes a threaded part connected to the mounting port and a limiting head placed below the base. The limiting head includes at least two limiting parts, which extend outward along the radial direction of the limiting head. The limiting parts can be connected to the tongue and groove hook of the profile.

[0024] The present invention has the following beneficial effects:

[0025] The tooling base forms a stable reference by fitting the plug-in part with the small gap of the profile tongue and groove, eliminating the reference drift problem caused by manual visual inspection, and improving the installation accuracy to ±1mm.

[0026] The dual-sided spacing measuring components slide independently and extend to the upper surface of the panel, automatically adapting to changes in the tilt angle of the magnetically shielded panel, thus solving the interference problem of traditional vernier scales when installed on concave / convex surfaces.

[0027] The laser projection module, combined with a photodetector, enables non-contact displacement detection. The displacement signal is amplified by moiré fringes, avoiding scratches on the coating and significantly improving efficiency.

[0028] The modular reference base and measurement components support quick assembly and disassembly, adapting to operations in confined spaces. The adjustment time for a single board is reduced to within 3 minutes, lowering the difficulty of operation for construction personnel. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the tooling base in this invention.

[0030] Figure 2 for Figure 1 Enlarged view of point A in the middle.

[0031] Figure 3 This is a front view of the panel with an inner concave surface installed in this invention.

[0032] Figure 4 for Figure 3 Enlarged view of point B in the middle.

[0033] Figure 5 This is a schematic diagram of the tooling base in Example 2.

[0034] Figure 6 This is a schematic diagram of the tooling base in Example 2.

[0035] Figure 7 This is a schematic diagram of the tooling base in Example 3.

[0036] Figure 8 This is the optical path diagram of the laser projection module in the tooling state in Example 3.

[0037] In the diagram: 100, Profile; 101, Tongue and groove joint; 200, Magnetic shielding panel; 201, Inner concave panel; 1, Reference base; 11, Connector; 111, Pin; 12, First base; 13, Second base; 14, Spacing adjustment component; 15, Bolt; 16, Locking component; 2, Measuring assembly; 21, Column; 22, Spacing measuring component; 221, Measuring head assembly; 222, Adaptive contour ruler; 223, Measuring mark; 23, Contact detection component; 24, Color display tank; 25, Color display strip; 26, Inclined pad; 27, Scale film; 3, Laser projection module; 31, Red laser emitting unit; 32, Blue laser emitting unit; 33, Diffraction grating plate; 34, Red parallel stripe group; 35, Blue parallel stripe group; 36, Overlapping projection area; 37, Cantilever bracket; 38, Photodetector; 4. Fastening bolt, 41. Screw part, 42. Limiting head, 421. Limiting part. Detailed Implementation

[0038] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Examples of the embodiments are shown in the drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout.

[0039] Example 1

[0040] like Figure 1 , 2 As shown, in this embodiment, the tooling base consists of a reference base 1 and a detachable measuring component 2. The bottom of the reference base 1 has a plug 11 with downwardly extending pins 111. The cross-sectional profile of the pins 111 strictly matches the inner wall shape of the profile tongue and groove 101, such as the trapezoidal cross-section of an I-beam slot, forming a physical reference through a small gap control within 0.1 millimeters. This fitting method completely eliminates the reference drift problem caused by traditional caliper clamping. The vertical column 21 of the measuring component 2 is fixed to the top of the reference base 1 by bolts 15 to ensure no displacement during construction vibration. The spacing measuring elements 22 symmetrically arranged on both sides of the column 21 can slide independently along the height direction of the column 21, and their measuring ends extend to the upper surface of the magnetic shielding panel 200. In this embodiment, the magnetic shielding panel 200 is made of permalloy to avoid direct contact with the coating during measurement and prevent damage.

[0041] The measuring head assembly 221 at the end of the spacing measuring component 22 includes an adaptive profile ruler 222, which abuts against the surface of the permalloy panel via a hinge mechanism. When the panel tilt angle changes, such as when the inner side of the mesh shell is concave or the outer side is convex, the profile ruler automatically deflects to a state parallel to the panel plane. The measuring mark 223 at its bottom adjusts its direction synchronously, ensuring the scale is always perpendicular to the panel edge. Specifically, for example, when installing a 13-degree inclined panel, the mark deflects 13 degrees to output the true distance value, fundamentally solving the projection error problem of the horizontal vernier ruler. This dynamic adaptation mechanism replaces the cumbersome process of replacing traditional special accessories.

[0042] The reference base 1 consists of a first base 12 and a second base 13, which are infinitely adjustable in width via an adjustable spacing component 14. In this embodiment, the adjustable spacing component uses an adjusting bolt, which can accommodate profile 100 size variations from 20 mm to 50 mm. A thermosensitive expansion layer is detachably installed on the side wall. In this embodiment, a paraffin composite material is used to achieve temperature compensation. When the ambient temperature of the construction site fluctuates, the difference in the expansion coefficient between this material and the metal substrate causes deformation compensation, effectively preventing reference drift. Fastening bolts 4 are inserted into the bottom mounting holes from bottom to top. The fastening bolts 4 are connected to the reference base via a screw part 41. The radial limiting part 421 of its limiting head 42 is designed as an L-shaped hook structure, which can hook the profile tongue and groove 101 to form a two-way mechanical lock. This installation method significantly improves the efficiency of disassembly and assembly, and is particularly suitable for situations where tooling needs to be placed laterally through the gaps in the permalloy panel in narrow spaces.

[0043] In this design, the small clearance fit of pin 111 eliminates displacement gaps through mechanical interference. Its tolerance of -0.1 mm to -0.2 mm, verified by finite element analysis, can withstand twenty times the construction vibration load, ensuring the reference accuracy remains stable within ±0.05 mm. The hinge mechanism of the adaptive contour ruler 222 employs a low-friction coefficient telescopic or elastic structure, with deflection resistance less than 0.1 Newtons within the 0-15 degree tilt angle range, ensuring the markings follow the panel plane changes in real time and eliminating angle-related errors. The paraffin composite material of the thermosensitive expansion layer exhibits linear expansion characteristics in the -10°C to 50°C range, compensating for 0.05 mm deformation per degree Celsius, maintaining installation accuracy within ±1.5 mm.

[0044] Furthermore, those skilled in the art can further extend the technical solution. For example, the pin 111 can be replaced with a single-pin, double-pin, or triple-pin base structure to match the irregular tongue and groove joint 101. This design originates from the classification data of three types of tongue and groove joints 101 in the acceptance test of aluminum alloy mesh shells. The scale markings of the adaptive contour ruler 222 can be replaced with a combination of inclined pad 26 and scale film. This solution has been verified in scaled-down prototype testing to meet the measurement requirements of tilt angles from 0 to 15 degrees, including inward tilt to 15 degrees and outward tilt to 15 degrees. The thermal expansion layer can be replaced with a bimetallic sheet compensation structure, which utilizes the thermal expansion difference of different metals to achieve temperature self-adaptation. The limiting part 421 of the fastening bolt 4 can be replaced with a T-bolt rotating lock, which completes the tooling fixation by rotating 90 degrees. This method improves efficiency by 70% in the tooling side-placement installation process.

[0045] In this embodiment, the small gap between the insert 111 and the profile tongue and groove 101 is controlled within one millimeter. When the cross-sectional profile of the insert 111 perfectly matches the inner wall of the I-beam slot, the micro-deformation generated by mechanical interference creates a self-locking effect. Under construction vibration conditions, this fit eliminates displacement gaps through intermolecular forces. Its direct effect is to compress the measurement reference drift to within ±0.5 millimeters, completely solving the reference instability problem caused by traditional caliper clamping.

[0046] The adaptive contour ruler 222 is essentially a contour reproduction mechanism. It can be a pin-type contour gauge for measuring the magnetic shielding panel 200 at various angles, or it can be constructed from multiple layers of flexible silicone sheets. When in contact with the permalloy panel surface (such as the concave inner surface or convex outer surface of the mesh shell), the silicone layer undergoes elastic deformation under contact pressure, accurately reproducing the local curvature of the panel surface. The bottom measuring mark 223 is linked to the deformation layer via a linkage mechanism. For example, when the panel is tilted at a 13-degree angle, the difference in compression of the deformation layer drives the mark to deflect synchronously by 13 degrees, ensuring that the scale direction is always perpendicular to the tangent of the panel edge. This process replaces manual visual alignment, controlling the reading error within 0.2 millimeters even at a 10-degree tilt.

[0047] In this embodiment, the column is provided with scale lines along its length to form a longitudinal measuring ruler, which is used by construction personnel to quickly read the height of the distance measuring components on both sides of the column. The column includes, but is not limited to, various forms such as single rulers, double rulers, and electronic displays. Single ruler columns are suitable for schemes where the distance measuring components on both sides of the column can be adjusted synchronously, while double ruler columns are suitable for schemes where the distance measuring components on both sides of the column can be adjusted independently. Columns equipped with electronic displays are more versatile and can be adapted to various distance measuring rulers, enabling fast and accurate height measurement.

[0048] Furthermore, during actual work, operators can also eliminate the use of the spacing measuring piece 22 and directly measure the horizontal distance and height between the magnetic shielding panels on both sides of the column and the measuring benchmark by carrying a ruler, thereby determining whether there is an installation error. This makes the structure of the tooling base simpler, which is the basic measurement scheme.

[0049] The temperature compensation function of the thermosensitive expansion layer is based on the principle of material phase change. The paraffin composite material exhibits linear expansion characteristics in the temperature range of -10°C to 50°C, and the difference in its expansion coefficient with the metal substrate creates a compensation amount. For every degree Celsius increase in ambient temperature, the thermosensitive layer expands by 0.05 mm, precisely offsetting the thermal expansion of the metal substrate. This passive compensation requires no external energy source and, in large, low-magnetic spaces with diurnal temperature variations of up to 30°C, successfully limits the deformation of the reference base 1 to within ±0.3 mm, maintaining overall installation accuracy within ±1 mm.

[0050] The ability to handle special working conditions further demonstrates the technological advantages. When working in confined spaces (permalloy panel gap ≤ 30mm), the L-shaped limiting head 42 of the fastening bolt 4 locks with the hook of the profile 100 by rotating 90 degrees. The tooling can be placed laterally through the gap and then reset for installation. In environments with large temperature differences, the thermosensitive expansion layer and the adjusting screw work synergistically: the adjusting screw addresses the manufacturing tolerance of the profile 100 width, and the thermosensitive layer compensates for temperature deformation, providing dual protection for reference stability. Panel surface coating protection is achieved through the low-pressure threshold of the contact detection element 23; a 0.5 Newton trigger value ensures that no scratches are produced when the measuring end lightly touches the surface.

[0051] The various subsystems work together to form a complete solution: the mechanical locking of the reference base 1 establishes an absolute reference, the dynamic adaptation of the measurement component 2 eliminates angular variables, the thermal compensation mechanism combats environmental interference, and intelligent feedback reduces human error. This integrated design enables the tooling to simultaneously meet the three core requirements of high precision, high efficiency, and low barrier to entry for magnetic shielding installation in large, low-magnetic spaces.

[0052] In practical applications, the construction personnel first align the pin 111 at the bottom of the reference base 1 with the tongue and groove 101 of the profile, and then apply slight pressure to create a small gap fit between the pin 111 and the inner wall of the tongue and groove 101. At this time, the tight fit between the cross-sectional profile of the pin 111 and the slot of the I-beam creates a self-locking effect, and the reference base 1 is firmly fixed in the measurement position. Subsequently, the lower end of the vertical column 21 of the measuring component 2 is inserted into the slot at the top of the reference base 1, and the bolt 15 is tightened to complete the rigid connection, ensuring that the column 21 does not shake during subsequent operations.

[0053] When adjusting the spacing measuring component 22, the construction personnel slide the measuring components on both sides of the column 21 to a predetermined height according to the spatial position of the permalloy panel. When the measuring end approaches the panel surface, the flexible silicone layer of the adaptive contour ruler 222 contacts the permalloy. For example, when installing the concave panel inside the mesh shell, the silicone layer in the middle of the contour ruler is subjected to greater pressure and undergoes deep deformation, while the deformation in the edge area is smaller, thus accurately reproducing the concave curvature. The bottom measuring mark 223 automatically deflects according to the deformation state through a linkage mechanism, so that the scale direction is always perpendicular to the tangent of the panel edge. The construction personnel directly read the scale value indicated by the mark, without the need for manual calculation of projection compensation. In this embodiment, the spacing measuring component 22 can also be a single ruler for direct distance measurement.

[0054] Environmental adaptability is demonstrated in two aspects: when encountering diurnal temperature variations, the thermosensitive expansion layer automatically compensates for the deformation of the metal substrate, maintaining baseline stability; when faced with profiles 100 of different widths, the operator rotates the adjusting screw to allow the first base 12 and the second base 13 to slide relative to each other, expanding or contracting the width of the reference base 1 to the matching size. After installation, the L-shaped limiting head 42 of the fastening bolt 4 hooks onto the profile tongue-and-groove 101 from below, achieving mechanical locking through a quarter turn. When working in confined spaces, the tool can be tilted laterally through the gap in the permalloy panel, and after resetting, the limiting head 42 can still accurately hook onto the hook.

[0055] In a practical application of a certain project, this tooling achieved full-process optimization: the time for benchmark installation was reduced from five minutes using the traditional method to thirty seconds; the single-board adjustment process, relying on LED pressure distribution indicators, required only three fine adjustments on average for construction personnel to meet the standard; and the thermal compensation mechanism ensured that the cumulative benchmark drift was less than 0.3 millimeters even in coastal areas with temperature differences of up to 30 degrees Celsius, allowing for continuous construction for seven days. The entire operation process requires no professional measurement knowledge.

[0056] The tooling disassembly follows a reverse process: first, loosen the fastening bolt 4 to release the hook of the limiting head 42; then, remove the bolts connecting the column and the base; next, open the locking fastener 16 to separate the first base 12 and the second base 13; finally, lift the base 1 to disengage the pin 111 from the profile tongue and groove 101. The modular design allows for independent maintenance of each component, such as replacing worn silicone deformation layers or LED units, significantly reducing maintenance costs.

[0057] Example 2

[0058] like Figure 6As shown, in this embodiment, a contact detection element 23 is added to the measuring end of the spacing measuring element 22. The internal pressure sensing unit is set with a trigger threshold of 0.5 Newtons and outputs a signal when the permalloy surface is lightly touched. The LED units embedded in the annular color display groove 24 are zoned to correspond to the pressure sensing areas. If the panel surface is uneven, causing abnormal local contact force, the corresponding LED will light up immediately. For example, when the contact force on the left exceeds the limit, the LED on the left will light up, accurately guiding the construction personnel to make targeted adjustments and avoiding the positioning ambiguity defects of traditional overall alarms. The LED zoned color display system converts the contact force distribution into 36 segments of light signals through spatial discrete sampling of the pressure sensing unit, enabling the construction personnel to quickly identify uneven areas and reducing the adjustment error rate by 90% in actual tests. The operational fault tolerance of the contact detection element 23 stems from the spatial discrete sampling design. The annular color display groove 24 is covered with a color display strip 25, and 36 LED units are set on the back of the color display strip 25, each connected to an independent pressure sensing zone. When there is a local protrusion on the permalloy panel surface, such as the presence of sand or other debris, the excessive contact pressure triggers the corresponding area LED to light up. For example, when the contact force in the third section on the left exceeds 0.5 Newtons, the LED in that section emits a red light, clearly indicating the local area that needs adjustment. This visual feedback mechanism reduces the error rate of adjustments by construction workers by 90%. In a field test of a large-scale low-magnetic space project, the average adjustment time for a single board was reduced from 15 minutes to 3 minutes.

[0059] In actual construction, the contact detection element 23 functions when the measuring end lightly touches the panel surface. When the local contact pressure exceeds 0.5 Newtons, the LED unit in the corresponding zone of the annular color display groove 24 lights up red. If the permalloy panel is tilted during installation, causing abnormal pressure on the right side, the LED group on the right side will remain lit, prompting the construction personnel to prioritize adjusting the fastening bolts 4 on that side. This visual guidance significantly lowers the operational threshold, allowing the construction team to quickly locate the problem area.

[0060] In addition, in this embodiment, such as Figure 3 , 4 As shown, for V-shaped installation positioning (outer convex panel of the mesh shell) and inverted V-shaped installation positioning (inner concave panel 201), the adaptive contour ruler 222 mentioned in Embodiment 1 can be omitted, and instead, a combination of inclined pad 26 and scale film 27 can be directly used. Figure 3 , 5As shown, based on the actual working condition requirement of a 10-degree inward tilt of the permalloy panel, the top surface of the inclined pad 26 is machined into a 13-degree inclined plane. This angle design ensures coverage of the maximum expected tilt angle. The bottom surface of the pad, made of hard aluminum alloy, is rigidly connected to the vernier scale with screws. The scale film consists of an anti-wear coating and fluorescent scale lines. Its base adhesive layer is firmly attached to the top surface of the pad, and the surface scale lines are printed according to the angle compensation value. For example, for a 10-degree tilt panel, the scale spacing of the film is pre-corrected according to the projection formula related to the sine trigonometric function, so that the scale value read by the construction personnel directly corresponds to the actual distance. This split design solves the problem of vernier scale interference when concave and convex surfaces coexist at the mesh shell nodes, while avoiding the aging risk of the silicone layer of the adaptive contour ruler 222 in extreme environments.

[0061] In practice, construction personnel need to match the pad model according to the site conditions. Thirteen-degree pads are used when installing the concave panel inside the mesh shell. Use a torque screwdriver to tighten the four M3 screws on the back of the pad to the bottom of the vernier caliper, ensuring the installation flatness error is less than 0.1 mm. Then, remove the release paper and precisely attach the pad along the baseline of the top edge, aligning it with the zero point of the vernier caliper using the crosshair on the edge of the release paper.

[0062] After the reference base 1 pin 111 is inserted into the profile tongue and groove 101, the vernier caliper is pushed so that the top surface of the pad contacts the target measurement point. For asymmetrical panel assemblies with different inclination angles on both sides, the construction personnel need to install pads of different angles on the left and right sides of the fixture respectively.

[0063] This solution demonstrates significant advantages in complex working conditions. When the panel height and angle at the reticulated shell nodes differ, construction personnel can independently adjust the height of the left and right vernier scales and match the corresponding pads. Actual measurement data shows that even under extreme conditions with a panel tilt angle difference of five degrees and a height difference of seven millimeters, the installation error of this solution is still controlled within ±0.5 millimeters. Maintenance only requires replacing worn film or locally deformed pads, reducing overall maintenance costs by 60% compared to the adaptive contour ruler 222.

[0064] Example 3

[0065] like Figure 7 , 8As shown, this embodiment integrates an optical detection system based on the mechanical positioning of Embodiment 1. The overall structure consists of a reference base 1 fixed to the profile tongue and groove 101, a vertical column 21, and a laser projection module 3. The pins 111 at the bottom of the reference base 1 maintain a small gap fit with the profile tongue and groove 101 within one millimeter, forming an immovable measurement reference. The vertical column 21 is rigidly connected to the top of the reference base 1 by bolts. The laser projection module 3 integrated at its top includes a red laser emitting unit 31 and a blue laser emitting unit 32 arranged side by side. The parallelism of the optical axes of the two emitting units is controlled within 0.1 degrees. A diffraction grating plate 33 is fixed five millimeters in front of it. The surface of this plate is etched with a parallel groove array of 200 lines per millimeter, and the groove depth is one-quarter of the wavelength of light.

[0066] The diffraction grating 33 decomposes the red laser into a group 34 of parallel red fringes with constant spacing, and the blue laser into a group 35 of parallel blue fringes with equal spacing. Due to the wavelength difference between the red laser (630 nm) and the blue laser (450 nm), the two fringes form an overlapping projection area 36 at a predetermined position 300 mm away from the pillar 21. This area is located at the theoretical installation position along the edge of the magnetic shielding panel 200. Within the overlapping area, the red and blue fringes interfere to form a moiré fringe pattern, the fringe spacing of which is determined by the difference in wavelengths and the geometric relationship of the projection.

[0067] A photodetector 38 is installed at the end of the cantilever bracket 37 extending from the side wall of column 21. The optical axis of the detector lens is strictly perpendicular to the mounting plane of the magnetic shielding panel 200, and the center of the lens is at the same height as the center of the overlapping projection area 36. The dual photosensitive element array inside the detector corresponds to the peak values ​​of the red and blue spectral responses: the peak sensitivity of the red channel is 630 nanometers, and that of the blue channel is 450 nanometers. When the construction personnel move the magnetic shielding panel 200 laterally, the edge of the panel cuts moiré fringes within the overlapping projection area 36. If the edge deviates from its theoretical position by 0.1 millimeters, the red and blue fringes will shift relative to each other, resulting in an imbalance of light intensity in the dual channels.

[0068] The differential amplifier circuit of photodetector 38 monitors changes in light intensity ratio in real time. When the edge of the panel is in the theoretical position, the red and blue stripes completely overlap, and the output voltage is balanced; when the edge deviates, the differential voltage exceeds the threshold, triggering an audible and visual alarm. The signal processing circuit has a built-in bandpass filter with a center frequency of 100 Hz to suppress ambient light interference. The rectangular hollow steel beam structure of the cantilever bracket 37 ensures that the detector's displacement is less than five micrometers under vibration.

[0069] The dual-wavelength selection of the laser projection module 3 is optimized based on the reflectivity of permalloy: 65% reflectivity for red laser and 42% for blue, enhancing stripe contrast. The grooves of the diffraction grating 33 are parallel to the edge extension direction of the panel, making the stripes perpendicular to the displacement detection direction. The photodetector 38 is loaded with a narrow-band filter (red passband 625-635nm, blue 445-455nm), maintaining a signal-to-noise ratio greater than 20 dB under 100,000 lux ambient light.

[0070] The spacing measuring elements 22 on both sides of the column 21 serve as auxiliary positioning devices, with their measuring ends extending to the upper surface of the magnetic shielding panel 200. When the construction personnel adjust the panel position laterally, they can directly read the distance between the edge and the tooling base by observing the scale of the measuring element. For example, if the edge of the panel contacts the 20mm scale line of the measuring element, it indicates that the current spacing is 20mm. The optical system works in conjunction with the mechanical measuring elements: the mechanical measuring elements provide a coarse adjustment reference, while the optical system achieves precise positioning at the zero-point-one-millimeter level.

[0071] Furthermore, for curved panel detection, the moiré fringes in the overlapping projection area 36 exhibit curvature changes at the curved edge. A preset algorithm compares the fringe curvature radius with the design curvature to automatically correct the displacement reading. For example, when there is an offset at an arc-shaped edge, the rate of change of fringe curvature is linearly related to the offset.

[0072] In this embodiment, the optical coordinate system established by the fixed fixture constitutes an absolute spatial reference. The laser projection module 3 generates red and blue interference fringes through the diffraction grating plate 33, forming an overlapping projection area 36 at a distance of 300 mm from the column 21. This area serves as the theoretical installation position of the edge of the magnetic shielding panel 200. When the fixture reference base 1 is fixed to the profile tongue and groove 101 with a small clearance fit, the spatial coordinates of the projection area are locked and unaffected by construction disturbances. Its technical effect is to eliminate the reference drift of traditional mobile measuring tools, maintain the stability of the coordinate origin in the construction of large facilities, and the measured reference drift is less than five micrometers.

[0073] The spacing measuring element 22 provides a relative distance reference. The independently sliding measuring ends on both sides of the column 21 extend to the surface of the magnetically shielded panel 200, and their scale marks directly indicate the millimeter-level distance between the panel edge and the tooling substrate. When the construction personnel move the panel laterally, they can observe the changes in the scale value of the measuring element to determine the real-time spacing. For example, if the panel edge contacts a 20mm scale line, the current spacing is 20mm, providing a more intuitive reflection of the coarse adjustment position than an optical system. This mechanical measurement serves as a redundant backup for the optical system, maintaining basic positioning functionality even under conditions of strong light interference.

[0074] The real-time feedback mechanism driven by photodetector 38 enables closed-loop control. When the panel edge cuts the moiré fringes within the overlapping projection area 36, ​​the relative displacement of the red and blue fringes is captured by the dual photosensitive element array, and the differential amplifier circuit converts the displacement signal into a voltage change. If the offset exceeds the 0.1 mm threshold, the signal processing circuit drives the audible and visual alarm to issue a warning. Its working principle is as follows: voltage imbalance triggers a three-level alarm—a single-frequency buzzer for 0.1 mm offset, a dual-frequency buzzer plus flashing yellow light for 0.2 mm offset, and a constant red light plus a continuous alarm for offsets above 0.3 mm. This tiered warning system allows construction personnel to quickly determine the adjustment direction, reducing the adjustment error rate by more than 80% in actual tests.

[0075] The synergy of three technical features forms a complete positioning system: the spatial benchmark established by the fixed tooling ensures a constant coordinate system, the mechanical measuring components provide real-time distance reference, and the optical feedback system achieves precise positioning. In large-scale industrial applications, this embodiment addresses three major pain points: First, the small-gap fitting of the 111 pins eliminates benchmark drift, keeping the cumulative installation error within ±0.8 mm; second, non-contact optical detection avoids scratching the permalloy coating, extending the service life of the magnetic shielding panel 200; and third, the audible and visual prompting system reduces the single-board adjustment time from 5-10 minutes to within 150 seconds, significantly improving construction efficiency.

[0076] In actual operation, the construction personnel first align the pin 111 at the bottom of the reference base 1 with the tongue and groove of the profile 101, and apply vertical pressure to make the pin 111 and the inner wall of the tongue and groove 101 form a small gap fit. At this time, the reference base 1 is firmly locked in the measurement position. Then, the lower end of the vertical column 21 is inserted into the top slot of the reference base 1, and the bolt is tightened to complete the rigid connection. The power of the laser projection module 3 at the top of the column 21 is turned on. The red and blue laser beams are decomposed into parallel stripe groups by the diffraction grating plate 33, forming an alternating red and blue overlapping projection area 36 at a distance of 300 mm from the column 21. This area is the theoretical installation position of the edge of the magnetic shielding panel 200.

[0077] When moving the magnetic shielding panel 200, the construction worker pushes the panel laterally along its width, gradually bringing the panel edge closer to the overlapping projection area 36. At this time, coarse positioning can be achieved using the spacing measuring pieces 22 on both sides of the column 21: slide the measuring piece until its end contacts the panel surface, and observe the real-time distance value indicated by the scale markings. For example, when the panel edge contacts the 20mm scale line on the measuring piece, it indicates that the current edge is 20mm from the fixture base. During the coarse adjustment phase, keep the panel edge moving within the projection area while simultaneously observing the status of the photoelectric detector 38.

[0078] The fine-tuning stage relies on an optical feedback system: when the panel edge cuts moiré fringes, the photodetector 38 monitors the red-blue light intensity ratio in real time. If the edge deviates from the theoretical position by more than 0.1 millimeters, the differential amplifier circuit output voltage becomes unbalanced, triggering an audible and visual alarm to emit a single-frequency buzzer. Construction personnel fine-tune the panel position according to the alarm direction: a rapid buzzer indicates adjustment to the left, while a gentle buzzer indicates adjustment to the right. When the deviation reaches 0.2 millimeters, the alarm escalates to a dual-frequency buzzer accompanied by a flashing yellow light; exceeding 0.3 millimeters results in a constant red light and a continuous alarm. This tiered prompting allows construction personnel to achieve precise positioning without needing to understand optical principles.

[0079] Environmentally adaptable operation includes: under strong ambient light conditions, the narrow-band filter loaded on the photodetector 38 automatically suppresses interference signals; when there are changes in day and night temperature differences, the thermosensitive expansion layer of the reference base 1 compensates for metal deformation through a paraffin phase change; when encountering profiles 100 of different widths, the width of the reference base 1 is expanded by rotating the adjusting screw to ensure a constant projection distance. When installing curved panels, the construction personnel correct the readings according to the preset curvature compensation algorithm—for example, when detecting an arc edge with a radius of three meters, the system automatically converts the stripe curvature into a displacement.

[0080] When disassembling the tooling, first turn off the laser power supply, loosen bolt 15 to separate column 21 from reference base 1, and finally lift reference base 1 to disengage pin 111 from profile tongue and groove 101. The laser module and photodetector 38 are separated through quick-release interface for easy individual maintenance or replacement.

[0081] It is also worth noting that when the project requires a change in the preset standard distance between the edge of the magnetic shielding panel 200 and the column 21, the laser projection system achieves rapid adaptation through mechanical and electrical coordinated adjustment. The construction personnel first operate the adjustment mechanism of the diffraction grating plate 33 of the laser projection module 3, which is mounted on a precision slide rail with axial graduations. If the design distance needs to be adjusted from 300 mm to 400 mm, the grating plate is moved backward along the slide rail to the corresponding graduation position, and then the fixing screws are tightened. This displacement changes the incident angle of the laser beam on the grating plate, causing the overlapping projection area 36 to synchronously migrate to 400 mm, maintaining the fringe imaging quality unaffected by distance changes. The position of the photodetector 38 is adjusted synchronously. The quick-release interface at the end of the cantilever bracket 37 uses a dovetail slider design; after releasing the latch, the detector can slide along the bracket guide rail. The operator uses a laser rangefinder to confirm that the center of the detector lens and the center of the new projection area are at the same horizontal level, then tightens the slider and uses a level to calibrate the verticality of the optical axis. This step ensures that the detection field of view accurately covers the displacement detection area, avoiding parallax errors introduced by changes in distance.

[0082] The distance correction knob in the signal processing circuit enables threshold recalibration. This knob is connected to an internal precision potentiometer, and its rotation angle is linearly related to the change in distance. For example, when the distance increases by 100 millimeters, rotating the knob clockwise by approximately 30 degrees will change the potentiometer resistance, reducing the differential voltage alarm threshold by 20%, compensating for the decrease in stripe displacement sensitivity caused by the increased projected distance. After adjustment, double verification is required: the audible and visual alarms should deactivate when the standard distance block is placed in the new theoretical position; and the single-frequency buzzer should respond normally when the offset is triggered using a 0.1 millimeter standard gauge.

[0083] For example, during the construction of a certain project, the installation distance of the magnetic shielding panel 200 was uniformly adjusted to 350 mm. The construction team performed a three-step adjustment on each fixture: the grating plate was moved back 50 mm to the 350 mm mark, the detector was moved outward 50 mm simultaneously, and the distance calibration knob was rotated 15 degrees uniformly. Actual measurement data showed that after the adjustment, the positioning error of the projection area did not exceed 0.3 mm, the alarm threshold drift was less than 5%, and the adjustment time for a single panel remained at approximately 110 seconds. The entire adjustment process took an average of three minutes per unit, without the need to replace optical components or use professional instruments for calibration.

[0084] The core technology of this adaptive design lies in converting changes in distance parameters into mechanical displacement. The sliding rail displacement ΔS of the diffraction grating plate 33 and the projection distance increment ΔL satisfy the condition that ΔS equals the product of ΔL and the tangent function of the grating diffraction angle θ, ensuring accurate migration of the projection area through trigonometric relationships. The detector displacement is equal to the projection distance increment, maintaining the coincidence of the field of view center. The circuit threshold adjustment is based on the inverse relationship between fringe displacement sensitivity and distance, achieving electrical parameter matching with changes in optical characteristics. This modular adjustment mechanism allows the same tooling to adapt to different engineering standards, significantly reducing equipment modification costs.

Claims

1. A measuring positioning tool for magnetic shielding panels, comprising a tool base mounted on an interpanel profile, characterized in that: The tool base includes a reference seat and a measurement assembly detachably connected above the reference seat; the bottom of the reference seat is provided with a plug-in part, which cooperates with the tongue-and-groove of the profile to form a measurement reference; the measurement assembly includes a vertical column and a spacing measurement member symmetrically arranged on both sides of the column; the spacing measurement member is slidable along the height direction of the column, and the measurement end thereof extends to the upper surface of the magnetic shielding panel; The top of the column is integrated with a laser projection module, which includes red and blue laser emitting units and a diffraction grating plate; the diffraction grating plate decomposes the red and blue lasers into red and blue parallel stripe groups with constant spacing, and the two stripe groups form an overlapping projection area at a preset position away from the column, which is located at the theoretical installation position of the edge of the magnetic shielding panel; the red and blue stripes in the overlapping projection area interfere to form a moire fringe pattern, and when the edge of the panel cuts the moire fringe, a photodetector monitors the red-to-blue light intensity ratio in real time; the side wall of the column is provided with a cantilever support, the optical axis of the photodetector at the end of the cantilever support is perpendicular to the installation plane of the magnetic shielding panel, and the lens center is at the same height as the projection area; the spacing measurement member includes a self-adaptive profiling ruler and a contact detection member with a pressure sensing unit.

2. The measurement positioning fixture of claim 1, wherein: The column and the reference seat are fixedly connected through a connecting piece; the plug-in part has a downward extending plug; the cross-sectional profile of the plug matches the inner wall profile of the profile tongue-and-groove; the plug cooperates with the tongue-and-groove gap.

3. The measurement positioning fixture of claim 1, wherein: The spacing measurement members on both sides of the column can be independently adjusted; the spacing measurement member includes a measurement head assembly matching the angle of the magnetic shielding panel.

4. The measurement positioning fixture of claim 3, wherein: The measurement head assembly includes a self-adaptive profiling ruler, which can abut against the angle of the magnetic shielding panel and adjust the extension direction of the bottom measurement scale.

5. The measurement positioning tool of claim 1, wherein: the red laser emitting unit and the blue laser emitting unit are arranged side by side; the diffraction grating plate is fixed in front of the emitting units.

6. The measurement positioning fixture of claim 5, wherein: The lens center of the photodetector is at the same height as the center of the overlapping projection area; the output end of the photodetector is connected to a signal processing circuit to connect a prompt device.

7. The measurement positioning fixture of claim 1, wherein: The measurement end of the spacing measurement member is provided with a contact detection member; the contact detection member is embedded with a pressure sensing unit; the contact surface of the pressure sensing unit can match the upper surface of the magnetic shielding panel.

8. The measurement positioning fixture of claim 7, wherein: The contact detection member includes a color developing groove arranged around the length direction of the spacing measurement member; the color developing groove is embedded with a color developing tape; the color developing tape includes a plurality of LED units arranged along the length direction; each LED unit is connected to the partitioned output end of the pressure sensing unit through an independent lead; the partitioned output end of the pressure sensing unit corresponds to the position of the LED unit.

9. The measurement positioning fixture of claim 2, wherein: The reference seat includes a first base and a second base that can slide relative to each other; an adjusting screw is arranged along the width direction between the first base and the second base; a lock piece is arranged on the first base and the second base; a heat-sensitive expansion layer is detachably arranged on the side wall of the reference seat along the width direction.

10. The measurement positioning fixture of any one of claims 1-9, wherein: The bottom of the reference seat is provided with a mounting hole, a fastening bolt is mounted in the mounting hole from bottom to top, the fastening bolt comprises a screw rod part connected to the mounting hole and a limiting head placed below the reference seat, the limiting head comprises at least two limiting parts, the limiting parts extend outward along the radial direction of the limiting head, and the limiting parts can be connected with the tongue-and-groove hooks of the profile.

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