Laser-based wind turbine blade web mold joint gap measuring device and method

Abstract

This invention relates to the field of wind turbine blade inspection technology, and discloses a device for measuring the gap between the web and the mold joint of a wind turbine blade using laser as a reference. The device includes: a reference laser emitter, fixedly mounted at the tail end of a fixture, for emitting a laser beam as a position reference; a self-propelled support mechanism, movably mounted on a guide rail laid on the fixture, capable of moving along the length of the web; a position-sensitive detector, mounted on the self-propelled support mechanism and positioned opposite the reference laser emitter, for receiving the reference laser beam and detecting the displacement of the self-propelled support mechanism relative to the reference laser emitter in real time; and a ranging mechanism, mounted on the self-propelled support mechanism, for measuring the vertical distance between the ranging mechanism and the upper surface of the web. This invention employs laser positioning and laser ranging principles, avoiding contact between the web and the fixture surface throughout the process, thus preventing scratches and contamination. The measurement accuracy is significantly higher than traditional methods, and the data consistency is strong.

Description

Technical Field

[0001] This invention relates to the field of wind turbine blade testing technology, and more specifically, to a non-contact measuring device and method for measuring the gap between the web and the mold joint of a wind turbine blade. Background Technology

[0002] The gap between the web and the mold joint during wind turbine blade installation is a key quality indicator affecting the blade's structural strength, assembly accuracy, and overall service life. As the main supporting structure inside the blade, the gap between the web and the blade shell must be controlled within a strict range (usually 3mm-8mm). An excessively large gap will affect the structural strength, while an excessively small gap may lead to assembly difficulties or stress concentration.

[0003] Currently, the industry commonly uses clay, glue, or feeler gauges for contact measurements. These traditional methods have the following inherent drawbacks: 1. Easily damages workpieces: Contact measurement can easily scratch the surface of the web plate and the reference surface of the tooling, causing damage to the workpiece and affecting the quality of the blades; 2. Low measurement accuracy and poor consistency: Large human error, differences in measurement results among different operators, and difficulty in ensuring consistency of multiple measurements by the same operator; 3. Low efficiency: It cannot meet the requirements of long-stroke, automated and continuous detection, especially for large wind turbine blades (which can be tens of meters long), where traditional measurement methods are time-consuming and labor-intensive.

[0004] Therefore, there is an urgent need for a non-contact, high-precision, stable and reliable mold gap measuring device that is suitable for long web plate detection. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing methods for measuring the gap between the web of wind turbine blades, such as easy damage to the workpiece, low accuracy, and low efficiency. This invention provides a measurement device and method that uses laser as a reference, non-contact measurement, high precision, and automated scanning.

[0006] This invention proposes a laser-based device for measuring the gap between the web and the mold joint of a wind turbine blade, comprising: A reference laser emitter is fixedly mounted at the tail end of the fixture and is used to emit a laser beam that serves as a position reference. The self-propelled bearing mechanism is movably mounted on the guide rails laid on the tooling frame and can move along the length of the web. A position-sensitive detector is installed on the self-propelled bearing mechanism and is positioned opposite to the reference laser emitter. It is used to receive the reference laser beam and detect the displacement of the self-propelled bearing mechanism relative to the reference laser emitter in real time. A ranging mechanism, mounted on the self-propelled bearing mechanism, is used to measure the vertical distance between the ranging mechanism and the upper surface of the web plate.

[0007] As a further optimization of the present invention, the reference laser emitter includes a phase laser rangefinder and a tilt sensor. The phase laser rangefinder is used to emit a laser beam as a position reference, and the tilt sensor is used to detect and compensate for the tilt angle of the mounting reference.

[0008] As a further optimization of the present invention, the self-propelled bearing mechanism includes a magnetic roller, a drive motor and a bearing plate. The magnetic roller is magnetically attracted to the guide rail, the drive motor drives the magnetic roller to rotate, and the ranging mechanism and the position sensitive detector are mounted on the bearing plate.

[0009] As a further optimization of the present invention, the self-propelled bearing mechanism further includes a driving gear and a driven gear. The output shaft of the drive motor is equipped with the driving gear, and the driven gear is mounted on the rotating shaft and meshes with the driving gear. The drive motor drives the magnetic roller to rotate through gear transmission.

[0010] As a further optimization of the present invention, the ranging mechanism includes at least one triangular laser rangefinder for measuring the vertical distance between the emission point and the upper surface of the web.

[0011] As a further optimization of the present invention, the ranging mechanism includes three triangular laser rangefinders arranged in parallel, with a light-blocking plate between adjacent rangefinders.

[0012] As a further optimization of the present invention, the position-sensitive detector is a PSD position-sensitive detector.

[0013] As a further optimization of the present invention, the device also includes a data processing system, which is electrically connected to the position-sensitive detector and the ranging mechanism, for collecting position data and distance data, and generating a web mold joint gap curve. The data processing system converts the distance data measured each time based on the difference between the current position detected by the position-sensitive detector and the initial absolute coordinates, and converts the measurement data back to the absolute coordinate system to eliminate position deviation during the walking process.

[0014] A method for measuring the gap between the web and the mold opening of a wind turbine blade, based on a laser, applied to the aforementioned device, includes the following steps: Initial positioning steps: Place the device at the beginning of the guide rail, calibrate the horizontal attitude of the reference laser emitter and make its emitted laser hit the center of the position-sensitive detector to establish an absolute coordinate reference; Scanning measurement steps: Drive the self-propelled bearing mechanism to move forward at a constant speed along the guide rail and stop at the preset measurement interval. The position sensitive detector reads the current position coordinates, and the ranging mechanism measures the vertical distance between the bearing and the upper surface of the web plate. Error compensation steps: The data measured at the current position is converted based on the difference between the real-time position detected by the position-sensitive detector and the initial absolute coordinates, and the measurement data is converted into the absolute coordinate system. Data processing steps: Fit the multi-point measurement data into the upper surface of the web plate, compare it with the standard web plate theoretical surface, and obtain the mold joint gap.

[0015] As a further optimization of the present invention, in the scanning measurement step, the preset measurement interval is 80mm; in the data processing step, surface fitting is performed using MATLAB software, and positions with gaps less than 3mm or greater than 8mm are marked as areas requiring manual trimming.

[0016] The laser-based device and method for measuring the gap between the web and the mold of wind turbine blades proposed in this invention have the following advantages: 1. It adopts the principle of laser positioning and laser ranging, without contacting the web plate and tooling surface throughout the process, avoiding scratches and contamination. The measurement accuracy is much higher than that of traditional methods, and the data consistency is strong. Moreover, through the cooperation of laser emitter and position sensor, the actual position of self-propelled bearing mechanism can be detected in real time. After comparing with the initial absolute coordinates, error compensation is performed, which effectively eliminates the installation error caused by long-distance laying of guide rails and position deviation during the movement.

[0017] 2. With the magnetic rollers and double-rimmed structure, it has the ability to automatically center, prevent derailment, and resist vibration interference. It can eliminate wheel-rail gap, reduce vibration, and ensure smooth operation over long distances. Moreover, the magnetic adsorption combined with the polyurethane-coated rollers will not scratch or indent the surface of the tooling, protect the installation reference accuracy, and meet the high cleanliness production requirements of wind turbine blades. In addition, the roller-type moving mechanism has low frictional resistance and fast running speed, which is more suitable for long axial scanning of the web plate than screw drive. There is no sagging or resonance, and the detection efficiency is greatly improved.

[0018] 3. By combining the phase laser rangefinder with the PSD, the position of the entire ranging device can be detected in real time, and the gap and flatness of the mold joint can be calculated quickly, simplifying the inspection process. Moreover, the measurement data can be collected, stored and output in real time, which facilitates quality traceability and process monitoring, and is suitable for the intelligent manufacturing and digital inspection needs of wind turbine blades.

[0019] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of one embodiment of the present invention.

[0021] Figure 2 This is a schematic diagram of the laser positioning mechanism of the present invention.

[0022] Figure 3 This is a schematic diagram of the laser ranging mechanism of the present invention.

[0023] Figure 4 This is a schematic diagram of the single-track self-propelled bearing mechanism of the present invention.

[0024] Figure 5 This is a schematic diagram of the overall structure of the tooling frame of the present invention.

[0025] Figure 6 This is a schematic diagram of the structure of the tail end of the tooling frame of the present invention. Explanation of the attached drawings

[0026] 1. Reference laser emitter; 101. Bracket; 102. Fixing plate; 103. Connecting plate; 104. Phase laser rangefinder; 105. Tilt sensor; 2. Distance measuring mechanism; 201. Square tube frame; 202. Rangefinder box; 203. Light shield; 204. Triangular laser rangefinder; 3. Self-propelled load-bearing mechanism; 301. Magnetic roller; 302. Rotating shaft; 303. Base plate; 304. Driving gear; 305. Guide rail; 306. Driven gear; 307. Long bolt; 308. Drive motor; 309. Support plate; 4. Web; 5. Wind turbine blades; 6. Tooling rack; 7. Position-sensitive detector. Detailed Implementation

[0027] Embodiments of the present invention are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar symbols denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0028] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0029] Please see Figures 1 to 6 The wind turbine blade web mold gap measuring device proposed in this invention, which uses laser as a reference, mainly includes a reference laser emitter 1, a self-propelled bearing mechanism 3, a position-sensitive detector 7, a ranging mechanism 2, and a data processing system.

[0030] In this embodiment, the device also includes a web plate to be tested 4, a wind turbine blade 5, and a fixture 6. The fixture 6 is used to fix the wind turbine blade and web plate to be tested, and a guide rail 305 is laid on it.

[0031] A reference laser emitter is fixedly mounted at the tail end of fixture 6 and is used to emit a laser beam that serves as a position reference, such as... Figure 2 As shown, the reference laser emitter includes a bracket 101, a fixing plate 102, a connecting plate 103, a phase laser rangefinder 104, and a tilt sensor 105; Bracket 101: Welded and fixed to the crossbeam at the tail end of the tooling frame 6, providing support for the entire reference laser emitter 1; Fixing plate 102: Located on the top of bracket 101, serving as an installation platform; Connecting plate 103: It is fixed to the fixing plate 102 by bolts; Phase laser rangefinder 104: Fixed on the connecting plate 103, used to emit a positioning laser beam as a position measurement reference for the self-propelled bearing mechanism 3; Tilt sensor 105: It is fixed to the mounting plate 102 by bolt connection and is used to detect the tilt angle of the installation reference and perform attitude compensation to ensure that the laser emission direction is horizontal.

[0032] The self-propelled bearing mechanism 3 is movably mounted on the guide rail 305 laid on the tooling frame 6, and can move along the length of the web plate, such as... Figure 4 As shown, the self-propelled bearing mechanism 3 includes a magnetic roller 301, a rotating shaft 302, a base plate 303, a driving gear 304, a driven gear 306, a long bolt 307, a drive motor 308, and a bearing plate 309. Magnetic rollers 301: There are four in number, distributed at the four corners, connected to the end of the rotating shaft 302 by a flat key and axially fixed with a round nut. The magnetic rollers 301 adopt a double-rim or grooved structure, which has automatic centering and anti-derailment functions. At the same time, they rely on magnetic force to be attracted to the metal guide rail, eliminating wheel-rail gap, reducing Z-axis runout, and achieving traceless movement. The surface of the magnetic rollers is covered with polyurethane elastic material, which does not scratch the surface of the tooling frame. Shaft 302: The first end is installed on the inner ring of the bearing, the outer ring of the bearing is interference-fitted with the base plate 303, and a double bearing symmetrical installation method is adopted; Driven gear 306: Connected to the middle section of rotating shaft 302 via a flat key; Drive motor 308: mounted on base plate 303, with drive gear 304 mounted on its output shaft, drive gear 304 meshing with driven gear 306 for transmission; Support plate 309: Installed on top of base plate 303 by long bolts 307, used to support the ranging mechanism 2 and position sensitive detector 7; When the drive motor 308 outputs power to drive the drive gear 304 to rotate, the drive gear 304 meshes with the driven gear 306, the driven gear 306 drives the rotating shaft 302 to rotate, and the rotating shaft 302 drives the magnetic roller 301 to move forward steadily along the guide rail 305.

[0033] Position-sensitive detector 7: In this embodiment, a PSD position-sensitive detector is preferably installed on the bearing plate 309 of the self-propelled bearing mechanism 3 and is set opposite to the phase laser rangefinder 104 of the reference laser emitter. It is used to receive the reference laser beam and detect the displacement of the self-propelled bearing mechanism relative to the reference laser emitter in real time. The laser beam emitted by the phase laser rangefinder 104 continuously illuminates the position-sensitive detector 7. The position-sensitive detector 7 can sense the change in the position of the center of the light spot in real time, thereby determining the real-time position offset of the self-propelled bearing mechanism 3 in the direction perpendicular to the laser beam (i.e., the web height direction). After comparing this position data with the initial position, the position deviation during the walking process can be calculated and used for error compensation of subsequent measurement data.

[0034] The ranging mechanism 2 is mounted on the bearing plate 309 of the self-propelled bearing mechanism 3, and is used to measure the vertical distance between the ranging mechanism and the upper surface of the web plate, such as... Figure 3 As shown, the ranging mechanism 2 includes a square tube frame 201, a rangefinder box 202, a light-blocking plate 203, and a triangular laser rangefinder 204; Square tube frame 201: One end is welded to the bearing plate 309, and the other end is welded to the rangefinder box 202, used to cantilever support the rangefinder box 202; Rangefinder box 202: It contains three parallel triangular laser rangefinders 204; Triangular laser rangefinder 204: used to measure the vertical distance from the emission point to the upper surface of the web plate 4. In this embodiment, three are set up so that the distance data of three points can be measured at the same time, thereby improving the measurement efficiency. Light-blocking plate 203: Installed between two adjacent triangular laser rangefinders 204 to prevent different rangefinders from receiving light returned by other rangefinders and causing interference.

[0035] The data processing system is electrically connected to the position-sensitive detector 7 and the ranging mechanism 2 to collect position data and distance data, and automatically generate the web mold joint gap curve. The data processing system can be a computer or industrial control computer with built-in data processing software such as MATLAB. It has the functions of real-time display and storage of measurement data. The system compares the distance data measured each time with the current position detected by the position sensitive detector and the initial absolute coordinates. After the computer analyzes the error, it converts the data measured at the current position into absolute coordinates, thereby eliminating the position deviation caused by the guide rail installation error during the movement.

[0036] The method for measuring the gap between the web and the mold joint of a wind turbine blade, based on a laser, provided by this invention, is implemented using the aforementioned device and specifically includes the following steps: S1: Initial Positioning and Coordinate Establishment Place the device at the starting end of the guide rail 305 of the tooling frame 6, and install the phase laser rangefinder 104 horizontally according to the tilt sensor 105 and make its emitted laser hit the center of the position sensitive detector 7, using this as the absolute coordinate; Among them, the laser path of the phase laser rangefinder 104 is used as the X-axis, the thickness direction of the web is used as the Y-axis, and the height direction is used as the Z-axis.

[0037] S2: Continuous scanning measurement After the system is started, the drive motor 308 drives the self-propelled bearing mechanism 3 to move forward at a constant speed, stopping after each preset distance, such as 80mm. The position-sensitive detector 7 reads the current real-time position coordinates (i.e., the center position of the light spot), while the triangular laser rangefinder 204 measures the vertical distance h from the emission point to the upper surface of the web plate 4 at this position.

[0038] S3: Position Error Compensation During the uniform forward movement of the self-propelled bearing mechanism 3, the vertical fluctuation position error caused by the guide rail installation error is reflected on the position sensitive detector 7. The system converts the data measured at the current position according to the difference between the real-time position detected by the position sensitive detector and the initial absolute coordinates, and converts the measurement data into the absolute coordinate system, thereby eliminating the position deviation during the movement.

[0039] S4: Surface Fitting and Gap Calculation The computer uses software such as MATLAB to fit the surface shape of the upper surface of the web plate in the absolute coordinate system by measuring data from several points. The fitted surface is compared with the theoretical surface of the standard web plate to obtain the mold gap value. Compared with the standard web plate, the gap is less than 3mm or greater than 8mm and is manually trimmed.

[0040] The scope of protection of this invention is not limited to the specific embodiments described above. Several typical variations are listed below, all of which fall within the scope of protection of this invention: Variant 1: Replacement of the driving method The drive motor is not limited to ordinary DC motors; frequency converter servo drives can also be used to achieve low-speed, high-stability operation.

[0041] Variant 2: Replacement of rangefinder type Rangefinders are not limited to triangulation laser rangefinders; they can also be phase-type laser rangefinders, pulse-type laser rangefinders, and other types.

[0042] Variation 3: Replacement of position detection methods Position detection is not limited to the combination of phase laser rangefinder + PSD; it can also be achieved using laser trackers, optical grating rulers, magnetic grating rulers, and other methods.

[0043] Variation 4: Replacement of the guiding method for moving mechanisms The guiding method is not limited to magnetic rollers and guide rails; linear guide rails, air-bearing guide rails, and other forms can also be used.

[0044] Variation 5: Changes in the number and layout of rangefinders The number of rangefinders is not limited to three; it can be set to one, two, four, or more depending on the measurement accuracy requirements. The layout can also be adjusted according to the width of the web.

[0045] Variation 6: Extension of Wireless Data Transmission It can be integrated with a wireless communication module to upload the detection data to the host computer or MES manufacturing execution system in real time, so as to realize online quality monitoring of the wind turbine blade production line.

[0046] Variation 7: Extension of the automatic lifting and leveling structure An automatic lifting and leveling structure can be added to the ranging mechanism to ensure that the rangefinder and the web surface always maintain the optimal measuring angle.

[0047] Variation 8: Expansion of Application Areas This invention is not only applicable to the detection of gaps in the web mold of wind turbine blades, but can also be extended to other applications requiring long-stroke, high-precision surface profile measurement, such as large steel structures, shipbuilding, aerospace and other fields.

[0048] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A device for measuring the gap between the web and the mold joint of a wind turbine blade using laser as a reference, characterized in that, include: A reference laser emitter (1) is fixedly mounted at the tail end of the fixture (6) and is used to emit a laser beam that serves as a position reference. The self-propelled bearing mechanism (3) is movably mounted on the guide rail (305) laid on the tooling frame (6) and can move along the length of the web plate (4); A position-sensitive detector (7) is installed on the self-propelled bearing mechanism (3) and is positioned opposite to the reference laser emitter (1). It is used to receive the reference laser beam and detect the displacement of the self-propelled bearing mechanism (3) relative to the reference laser emitter (1) in real time. The distance measuring mechanism (2) is installed on the self-propelled bearing mechanism (3) and is used to measure the vertical distance between the distance measuring mechanism (2) and the upper surface of the web plate (4).

2. The laser-based wind turbine blade web mold gap measuring device according to claim 1, characterized in that, The reference laser emitter includes a phase laser rangefinder (104) and a tilt sensor (105). The phase laser rangefinder (104) is used to emit a laser beam as a position reference, and the tilt sensor (105) is used to detect and compensate for the tilt angle of the mounting reference.

3. The laser-based wind turbine blade web mold gap measuring device according to claim 1, characterized in that, The self-propelled bearing mechanism (3) includes a magnetic roller (301), a drive motor (308), and a bearing plate (309). The magnetic roller (301) is magnetically attracted to the guide rail (305). The drive motor (308) drives the magnetic roller (301) to rotate. The ranging mechanism (2) and the position sensitive detector (7) are mounted on the bearing plate (309).

4. The laser-based wind turbine blade web mold gap measuring device according to claim 3, characterized in that, The self-propelled bearing mechanism (3) further includes a drive gear (304) and a driven gear (306). The output shaft of the drive motor (308) is equipped with the drive gear (304), and the driven gear (306) is mounted on the rotating shaft (302) and meshes with the drive gear (304). The drive motor (308) drives the magnetic roller (301) to rotate through gear transmission.

5. The laser-based wind turbine blade web mold gap measuring device according to claim 1, characterized in that, The ranging mechanism (2) includes at least one triangular laser rangefinder (204) for measuring the vertical distance between the emission point and the upper surface of the web (4).

6. The laser-based wind turbine blade web mold gap measuring device according to claim 5, characterized in that, The ranging mechanism (2) includes three parallel triangular laser rangefinders (204), with a light-blocking plate (203) between adjacent rangefinders.

7. The laser-based wind turbine blade web mold gap measuring device according to claim 1, characterized in that, The position-sensitive detector (7) is a PSD position-sensitive detector.

8. The laser-based wind turbine blade web mold gap measuring device according to claim 1, characterized in that, It also includes a data processing system, which is electrically connected to the position-sensitive detector (7) and the ranging mechanism (2) to collect position data and distance data and generate the web mold joint gap curve; The data processing system converts the distance data measured each time based on the difference between the current position detected by the position-sensitive detector (7) and the initial absolute coordinates, and converts the measurement data into the absolute coordinate system to eliminate position deviation during the walking process.

9. A method for measuring the gap between the web and the mold joint of a wind turbine blade using a laser as a reference, applied to the apparatus described in any one of claims 1 to 8, characterized in that, Includes the following steps: Initial positioning steps: Place the device at the beginning of the guide rail (305), calibrate the horizontal attitude of the reference laser emitter (1) and make its emitted laser hit the center of the position sensitive detector (7) to establish an absolute coordinate reference; Scanning measurement steps: Drive the self-propelled bearing mechanism (3) to move forward at a constant speed along the guide rail (305), stop at the preset measurement interval, read the current position coordinates of the position sensitive detector (7), and measure the vertical distance between the measuring mechanism (2) and the upper surface of the web plate (4). Error compensation steps: The data measured at the current position is converted according to the difference between the real-time position detected by the position-sensitive detector (7) and the initial absolute coordinates, and the measurement data is converted into the absolute coordinate system; Data processing steps: Fit the multi-point measurement data into the upper surface of the web plate, compare it with the standard web plate theoretical surface, and obtain the mold joint gap.

10. The method for measuring the gap between the web and the mold opening of a wind turbine blade based on a laser as described in claim 9, characterized in that, In the scanning measurement step, the preset measurement interval is 80mm; in the data processing step, surface fitting is performed using MATLAB software, and positions with gaps less than 3mm or greater than 8mm are marked as areas requiring manual trimming.

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