Method and equipment for measuring wall thickness of optical fiber capillary tube

Abstract

The invention relates to the technical field of pipeline measurement, and discloses an optical fiber capillary tube wall thickness measurement method and device, and the method comprises the following steps: S1, obtaining a to-be-measured capillary tube and a steel wire; s2, performing contact measurement on the outer surface of the capillary tube to be measured by using a deep hole gauge; s3, measuring along the axial direction of the capillary tube to be measured; and S4, inputting the measured data into a data processing module, generating a wall thickness uniformity model through a three-dimensional modeling algorithm, and outputting a wall thickness deviation value. The equipment comprises a base, a clamping assembly, a measuring assembly and a data processing module, and integrates a three-dimensional modeling and deviation analysis process. The steel wire with the diameter accurately matched with the standard diameter of the inner hole of the capillary tube is used as an internal support, so that measurement errors caused by small diameter of the inner hole of the capillary tube and limitation of depth of field are effectively avoided, and meanwhile, the stability in the measurement process is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of pipeline measurement, and in particular to a method and equipment for measuring the wall thickness of an optical fiber capillary. Background Art

[0002] As a precision optical device, the uniformity of the wall thickness and dimensional accuracy of the optical fiber capillary directly affect the performance and reliability of the optical fiber device. In the process of optical fiber manufacturing and packaging, the wall thickness measurement of the optical fiber capillary is one of the key processes.

[0003] After searching, the Chinese patent number CN116929178A discloses a method for measuring the wall thickness of an optical fiber capillary, which includes the following steps: obtaining a capillary to be measured and a steel wire, passing the steel wire through the capillary to be measured, and straightening the steel wire; obtaining a deep hole gauge, the deep hole gauge contacts the surface of the capillary to be measured, the capillary to be measured rotates one circle, and reading the data of the wall thickness of one circle; dividing the capillary to be measured into sections according to a predetermined distance, and measuring the wall thickness data of the capillary to be measured at equal intervals; an optical fiber capillary wall thickness measuring device includes a bracket, a deep hole gauge, a slide rail, and a steel wire, the deep hole gauge is connected to the bracket; the slide rail is slidably connected to the deep hole gauge; the steel wire is connected to the bracket, the steel wire and the slide rail are relatively parallel, and the steel wire is connected to the capillary to be measured to realize the measurement process.

[0004] It can be seen from the above-mentioned comparative patents that the existing measurement methods can be roughly divided into optical microscopic imaging method and contact mechanical measurement method. The optical microscopic imaging method observes the capillary cross section through a high-power microscope, but due to the small diameter of the inner hole of the optical fiber capillary, usually between 1.0mm and 5.0mm, the depth of field of the microscope makes it difficult to accurately measure the wall thickness of the inner wall of the deep hole, especially in the case of a large aperture, the measurement error is significant. Secondly, the microscopic imaging method cannot achieve continuous measurement of the entire length of the capillary, and it is difficult to evaluate the uniformity of the wall thickness, so it cannot be used in a measurement environment with precision requirements; and the contact mechanical measurement method directly contacts the capillary surface through a probe or a probe, and uses a depth sensor to obtain wall thickness data. However, this method has the following problems in practical applications: first, the contact between the probe and the capillary surface is easy to introduce slight deformation, resulting in measurement errors. Secondly, traditional contact measurement equipment usually requires complex adjustment and calibration, and the operation is cumbersome and inefficient. Based on this, the present invention designs a method and device for measuring the wall thickness of an optical fiber capillary to solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to provide a method and device for measuring the wall thickness of an optical fiber capillary, which solves the problems of large measurement error and low efficiency in the background technology.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: A method for measuring the wall thickness of an optical fiber capillary comprises the following steps: Step S1, obtaining a capillary tube to be measured and a steel wire, wherein the diameter of the steel wire meets the matching tolerance of ±0.005 mm with the standard diameter of the inner hole of the capillary tube to be measured, and the straightness error does not exceed 0.01 mm / m, and the steel wire is inserted into the inner hole of the capillary tube to be measured and straightened; Step S2, using a deep hole gauge to perform contact measurement on the outer surface of the capillary to be measured, the measurement accuracy of the probe of the deep hole gauge is ±0.1 micron, and the contact pressure is 0.5 Newton ±0.1 Newton, the deep hole gauge is moved along the slide rail to contact the outer surface of the capillary to be measured, the capillary to be measured is driven to rotate 360 ​​degrees at a speed of 1 revolution per minute, the wall thickness data is collected every 10 degrees, and the full-circle wall thickness data is recorded; Step S3, performing segmented measurement at segment intervals of 2 mm along the axial direction of the capillary to be measured, and repeating step S2 to obtain full-length wall thickness distribution data of the capillary to be measured; Step S4, inputting the measured data into the data processing module, generating a wall thickness uniformity model through a three-dimensional modeling algorithm, and outputting a wall thickness deviation value.

[0007] Preferably, before step S1, it also includes: step S0, straightening the steel wire, adjusting the steel wire to be parallel to the deep hole gauge slide rail, and clamping it on a bracket, a three-jaw chuck is provided on the bracket to fix the steel wire, ensuring that the steel wire remains stable during the measurement process to avoid measurement errors caused by shaking of the steel wire, and the clamping surface of the three-jaw chuck is also provided with anti-slip texture.

[0008] Before the measurement begins, you first need to straighten the wire and adjust it to be parallel to the deep hole gauge rail. The wire is fixed to the bracket by a three-jaw chuck. The clamping surface of the three-jaw chuck is provided with anti-slip patterns to ensure that the wire remains stable during the measurement process and avoid measurement errors caused by wire shaking. The matching tolerance between the wire diameter and the standard diameter of the capillary inner hole to be measured is ±0.005 mm, and the straightness error does not exceed 0.01 mm / m, ensuring that the wire can be evenly distributed in the capillary inner hole, providing a stable benchmark for subsequent measurements.

[0009] Preferably, in step S2, the probe of the deep hole gauge is made of high-precision ceramic material with a measurement accuracy of ±0.1 micron, and the slide rail adopts a high-precision linear guide rail with a straightness error of no more than 0.01 mm / m, thereby ensuring that the deep hole gauge remains stable during movement.

[0010] Preferably, in step S2, the outer surface of the capillary to be measured is cleaned before measurement by wiping with anhydrous ethanol and a clean cotton cloth to remove oil and dust on the surface to ensure the accuracy of the measurement data.

[0011] Insert the steel wire into the inner hole of the capillary to be measured and straighten it. The matching tolerance between the steel wire diameter and the standard diameter of the capillary inner hole is ±0.005 mm, ensuring that the steel wire fits tightly in the capillary inner hole to avoid measurement errors caused by the gap between the steel wire and the inner hole. The straightness error of the steel wire does not exceed 0.01 mm / m, ensuring that the steel wire remains straight in the capillary inner hole, providing a stable benchmark for subsequent measurements.

[0012] Preferably, the data processing module is integrated in an industrial-grade computer, has a built-in 3D modeling algorithm and an automated control program, supports data export formats including CSV, JSON and 3D point cloud files, and generates a wall thickness uniformity model through a 3D modeling algorithm; the wall thickness deviation value is calculated as follows: wall thickness deviation = ((measured wall thickness - standard wall thickness) / standard wall thickness) × 100%, the standard wall thickness is the theoretical wall thickness of the capillary design, the measured wall thickness is the wall thickness value obtained by actual measurement, and the wall thickness deviation does not exceed 2% of the standard wall thickness.

[0013] A deep hole gauge is used to perform contact measurement on the outer surface of the capillary to be measured. The probe of the deep hole gauge is made of high-precision ceramic material, with a measurement accuracy of ±0.1 micron and a contact pressure of 0.5 N ±0.1 N, ensuring stable contact between the probe and the outer surface of the capillary during the measurement process to avoid measurement errors caused by excessive or insufficient contact pressure. The deep hole gauge moves along a high-precision linear guide rail with a straightness error of no more than 0.01 mm / m, ensuring that the deep hole gauge remains stable during movement to avoid measurement errors caused by unevenness of the rail.

[0014] Preferably, the resolution of the wall thickness uniformity model is not less than 0.01 mm, and a wall thickness distribution curve graph can be generated, wherein the abscissa of the curve graph is the axial position of the capillary in millimeters, and the ordinate is the wall thickness value in micrometers.

[0015] During the measurement process, the deep hole gauge moves along the slide rail to contact the outer surface of the capillary to be measured, driving the capillary to be measured to rotate 360° at a speed of 1 rpm, collecting wall thickness data every 10°, and recording the full-circle wall thickness data. The rotation of the capillary and the movement of the deep hole gauge are achieved through precise mechanical linkage to ensure that the measurement points are evenly distributed. The frequency of data collection is 10 times per second to ensure that enough data points are collected during the rotation of the capillary to ensure the integrity and accuracy of the wall thickness data.

[0016] Along the axial direction of the capillary to be measured, segmented measurements are performed at segment intervals of 2 mm, and step S2 is repeated to obtain the full-length wall thickness distribution data of the capillary to be measured. At each segmented position, the deep hole gauge moves along the slide rail to contact the outer surface of the capillary, driving the capillary to rotate 360°, collecting wall thickness data every 10°, and recording the full-circle wall thickness data. Through segmented measurement, the wall thickness distribution data within the full length of the capillary can be obtained to ensure the comprehensiveness and accuracy of the measurement results. The wall thickness uniformity model is generated through a three-dimensional modeling algorithm, and the resolution of the model is not less than 0.01 mm, which can clearly show the distribution of the capillary wall thickness.

[0017] Preferably, a method for measuring the wall thickness of an optical fiber capillary provides an optical fiber capillary wall thickness measuring device for measuring the wall thickness of a capillary to be measured, the device comprising: A base, a stepping motor is installed on the top of the base for rotating the capillary to be measured, and a guide rail is also installed on the top of the base for moving the top assembly; A clamping assembly, which is mounted on the top of the base and is used to fix the capillary to be measured; A measuring component, which is installed on one side of the clamping component and is used to measure the wall thickness of the capillary; Data processing module, integrating 3D modeling and deviation analysis programs.

[0018] Preferably, the clamping assembly includes a sliding seat slidably connected to the top of the guide rail, a moving frame is installed on the top of the sliding seat, the top of the moving frame is slidably connected to the moving seat, a three-jaw clamping seat is installed at the bottom of the moving seat and is used for clamping the capillary, an electric push rod is fixedly connected to the inner wall of the three-jaw clamping seat, and a clamping block is installed on one side of the electric push rod.

[0019] Preferably, the measuring assembly includes a measuring seat slidably connected to the top of the guide rail, a support frame is installed on the top of the measuring seat, a threaded hole is opened on the top of the support frame, a threaded rod is threadedly connected in the inner cavity of the threaded hole, a crank is installed on the top of the threaded rod, a lifting block is installed on the bottom of the threaded rod and the threaded rod and the lifting block are rotatably connected via a bearing, and a deep hole measuring gauge is installed on the bottom of the lifting block for measurement.

[0020] Preferably, a laser calibrator is installed on the top of the base for real-time monitoring of the parallelism between the steel wire and the slide rail; the data processing module is electrically connected to the clamping assembly, the measuring assembly and the laser calibrator.

[0021] Compared with the prior art, the beneficial effects achieved by the present invention are: 1. The present invention adopts a steel wire whose diameter is precisely matched with the standard diameter of the inner hole of the capillary as an internal support, thereby effectively avoiding the measurement error caused by the small diameter of the inner hole of the capillary and the limitation of the depth of field, while ensuring the stability during the measurement process; the deep hole gauge probe and high-precision linear guide made of high-precision ceramic materials are used to significantly improve the accuracy and repeatability of the measurement, and reduce the error caused by insufficient equipment accuracy.

[0022] 2. The present invention can comprehensively obtain the wall thickness distribution within the entire length of the capillary by measuring in sections at intervals of 2 mm along the axial direction of the capillary and collecting the wall thickness data of the entire circumference in combination with the rotation of the capillary, thereby solving the problem that the traditional method cannot continuously measure and evaluate the uniformity of the wall thickness. The data processing module uses a three-dimensional modeling algorithm to generate a wall thickness uniformity model to intuitively display the wall thickness distribution.

[0023] 3. The non-contact internal support method of the present invention avoids the slight deformation that may be introduced by the direct contact between the probe and the capillary surface in traditional contact measurement, thereby reducing the resulting measurement errors; the equipment design simplifies the adjustment and calibration steps before measurement, and through the integrated data processing module and automatic control program, improves the measurement efficiency and reduces the complexity of operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a process flow chart of the present invention; Figure 2 It is a schematic diagram of the device structure of the present invention; Figure 3 It is a side view of the equipment structure of the present invention; Figure 4 For the present invention Figure 3 A magnified image of point A; Figure 5 It is a schematic structural diagram of the clamping assembly of the present invention; Figure 6 It is a schematic diagram of the structure of the measuring assembly of the present invention; Figure 7 For the present invention Figure 6 Enlarged view of point B.

[0025] Among them: 2. Clamping assembly; 3. Measuring assembly; 101. Base; 102. Stepper motor; 103. Guide rail; 104. Laser calibrator; 201. Sliding seat; 202. Moving frame; 203. Moving seat; 204. Three-jaw clamping seat; 205. Electric push rod; 206. Clamping block; 301. Measuring seat; 302. Support frame; 303. Threaded rod; 304. Crank; 305. Lifting block; 306. Deep hole measuring gauge. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] Example 1: Please refer to Figure 1-Figure 7 In an embodiment of the present invention, a method for measuring the wall thickness of an optical fiber capillary comprises the following steps: Step S1, obtaining a capillary tube to be measured and a steel wire, wherein the diameter of the steel wire meets the matching tolerance of ±0.005 mm with the standard diameter of the inner hole of the capillary tube to be measured, and the straightness error does not exceed 0.01 mm / m, and the steel wire is inserted into the inner hole of the capillary tube to be measured and stretched straight; Step S2, using a deep hole gauge to perform contact measurement on the outer surface of the capillary to be measured, the measurement accuracy of the probe of the deep hole gauge is ±0.1 micron, and the contact pressure is 0.5 N ±0.1 N. The deep hole gauge is moved along the slide rail to contact the outer surface of the capillary to be measured, and the capillary to be measured is driven to rotate 360° at a speed of 1 rpm, and the wall thickness data is collected every 10°, and the full-circle wall thickness data is recorded; Step S3, performing segmented measurement at a segmented interval of 2 mm along the axial direction of the capillary to be measured, and repeating step S2 to obtain the full-length wall thickness distribution data of the capillary to be measured; Step S4, inputting the measured data into the data processing module, generating a wall thickness uniformity model through a three-dimensional modeling algorithm, and outputting a wall thickness deviation value.

[0028] Before step S1, it also includes: step S0, straightening the steel wire, adjusting the steel wire to be parallel to the deep hole gauge slide rail, and clamping it on a bracket. A three-jaw chuck is provided on the bracket to fix the steel wire to ensure that the steel wire remains stable during the measurement process to avoid measurement errors caused by shaking of the steel wire. The clamping surface of the three-jaw chuck is also provided with anti-slip texture.

[0029] In step S2, the probe of the deep hole gauge is made of high-precision ceramic material with a measurement accuracy of ±0.1 micron, and the slide rail adopts a high-precision linear guide with a straightness error of no more than 0.01 mm / m, thereby ensuring that the deep hole gauge remains stable during movement.

[0030] In step S2, the outer surface of the capillary to be measured is cleaned before measurement by wiping with anhydrous ethanol and a clean cotton cloth to remove oil and dust on the surface to ensure the accuracy of the measurement data.

[0031] The data processing module is integrated in an industrial-grade computer with built-in 3D modeling algorithms and automated control programs. It supports data export formats including CSV, JSON and 3D point cloud files, and generates a wall thickness uniformity model through a 3D modeling algorithm. The wall thickness deviation value is calculated as follows: Wall thickness deviation = ((measured wall thickness - standard wall thickness) / standard wall thickness) × 100%, where the standard wall thickness is the theoretical wall thickness of the capillary design, and the measured wall thickness is the wall thickness value obtained by actual measurement. The wall thickness deviation does not exceed 2% of the standard wall thickness.

[0032] The resolution of the wall thickness uniformity model is not less than 0.01 mm, and a wall thickness distribution curve graph can be generated, wherein the abscissa of the curve graph is the axial position of the capillary in millimeters, and the ordinate is the wall thickness value in micrometers.

[0033] The working principle of the embodiment of the present invention is: before the measurement begins, the steel wire needs to be straightened and adjusted to be parallel to the deep hole gauge slide rail. The steel wire is fixed to the bracket by a three-jaw chuck, and the clamping surface of the three-jaw chuck is provided with anti-slip texture to ensure that the steel wire remains stable during the measurement process and avoid measurement errors caused by the shaking of the steel wire. The matching tolerance between the diameter of the steel wire and the standard diameter of the inner hole of the capillary to be measured is ±0.005 mm, and the straightness error does not exceed 0.01 mm / m, ensuring that the steel wire can be evenly distributed in the inner hole of the capillary, providing a stable benchmark for subsequent measurements.

[0034] Insert the steel wire into the inner hole of the capillary to be measured and straighten it. The matching tolerance between the steel wire diameter and the standard diameter of the capillary inner hole is ±0.005 mm, ensuring that the steel wire fits tightly in the capillary inner hole to avoid measurement errors caused by the gap between the steel wire and the inner hole. The straightness error of the steel wire does not exceed 0.01 mm / m, ensuring that the steel wire remains straight in the capillary inner hole, providing a stable benchmark for subsequent measurements.

[0035] A deep hole gauge is used to perform contact measurement on the outer surface of the capillary to be measured. The probe of the deep hole gauge is made of high-precision ceramic material, with a measurement accuracy of ±0.1 micron and a contact pressure of 0.5 N ±0.1 N, ensuring stable contact between the probe and the outer surface of the capillary during the measurement process to avoid measurement errors caused by excessive or insufficient contact pressure. The deep hole gauge moves along a high-precision linear guide rail with a straightness error of no more than 0.01 mm / m, ensuring that the deep hole gauge remains stable during movement to avoid measurement errors caused by unevenness of the rail.

[0036] During the measurement process, the deep hole gauge moves along the slide rail to contact the outer surface of the capillary to be measured, driving the capillary to be measured to rotate 360° at a speed of 1 rpm, collecting wall thickness data every 10°, and recording the full-circle wall thickness data. The rotation of the capillary and the movement of the deep hole gauge are achieved through precise mechanical linkage to ensure that the measurement points are evenly distributed. The frequency of data collection is 10 times per second to ensure that enough data points are collected during the rotation of the capillary to ensure the integrity and accuracy of the wall thickness data.

[0037] Along the axial direction of the capillary to be measured, segmented measurements are performed at segment intervals of 2 mm, and step S2 is repeated to obtain the full-length wall thickness distribution data of the capillary to be measured. At each segmented position, the deep hole gauge moves along the slide rail to contact the outer surface of the capillary, driving the capillary to rotate 360°, collecting wall thickness data every 10°, and recording the full-circle wall thickness data. Through segmented measurement, the wall thickness distribution data within the full length of the capillary can be obtained to ensure the comprehensiveness and accuracy of the measurement results. The wall thickness uniformity model is generated through a three-dimensional modeling algorithm, and the resolution of the model is not less than 0.01 mm, which can clearly show the distribution of the capillary wall thickness.

[0038] Example 2: Please refer to Figure 1-Figure 7 In an embodiment of the present invention, a method for measuring the wall thickness of an optical fiber capillary is provided, and an optical fiber capillary wall thickness measuring device is provided, which is used to measure the wall thickness of the capillary to be measured, and the device includes:

[0039] A base 101, a stepper motor 102 is installed on the top of the base 101 for rotating the capillary to be measured, and a guide rail 103 is also installed on the top of the base 101 for moving the top assembly; A clamping assembly 2, which is mounted on the top of the base 101 and is used to fix the capillary to be measured; A measuring component 3, which is installed on one side of the clamping component 2 and is used to measure the wall thickness of the capillary; Data processing module, integrating 3D modeling and deviation analysis programs.

[0040] The clamping assembly 2 includes a sliding seat 201 slidably connected to the top of the guide rail 103, a moving frame 202 is installed on the top of the sliding seat 201, a moving seat 203 is slidably connected to the top of the moving frame 202, a three-jaw clamping seat 204 is installed at the bottom of the moving seat 203 and is used for clamping the capillary, an electric push rod 205 is fixedly connected to the inner wall of the three-jaw clamping seat 204, and a clamping block 206 is installed on one side of the electric push rod 205.

[0041] The measuring assembly 3 includes a measuring seat 301 slidably connected to the top of the guide rail 103, a support frame 302 is installed on the top of the measuring seat 301, a threaded hole is opened on the top of the support frame 302, a threaded rod 303 is threadedly connected in the inner cavity of the threaded hole, a crank 304 is installed on the top of the threaded rod 303, a lifting block 305 is installed at the bottom of the threaded rod 303, and the threaded rod 303 and the lifting block 305 are rotatably connected through a bearing, and a deep hole measuring gauge 306 is installed at the bottom of the lifting block 305 for measurement.

[0042] A laser calibrator 104 is installed on the top of the base 101 for real-time monitoring of the parallelism between the steel wire and the slide rail; the data processing module is electrically connected to the clamping component 2, the measuring component 3 and the laser calibrator 104.

[0043] The working principle of the embodiment of the present invention is: first, the capillary to be measured is placed on the three-claw clamping seat 204 of the clamping assembly 2, and the clamping block 206 can evenly clamp the capillary through the extension and retraction of the electric push rod 205 to ensure that the capillary remains stable during the measurement process. The clamping assembly 2 is installed on the guide rail 103 of the base 101, and the position of the clamping assembly 2 can be adjusted by moving the sliding seat 201 on the guide rail 103 to adapt to capillaries of different lengths.

[0044] The sliding seat 201 of the clamping assembly 2 moves on the guide rail 103, and after being adjusted to a suitable position, the position of the capillary is further fine-tuned through the cooperation of the moving frame 202 and the moving seat 203 to ensure that the central axis of the capillary is aligned with the measuring axis of the deep hole measuring gauge 306 of the measuring assembly 3. The clamping block 206 of the three-jaw clamping seat 204, under the action of the electric push rod 205, evenly clamps the capillary to prevent the capillary from shaking or displacement during the measurement process.

[0045] The measuring assembly 3 is mounted on the guide rail 103. The position of the measuring assembly 3 is adjusted by moving the measuring seat 301 on the guide rail 103 so that it contacts the outer surface of the capillary. A support frame 302 is mounted on the top of the measuring seat 301. A threaded hole is provided on the top of the support frame 302. A threaded rod 303 is threadedly connected to the inner thread of the threaded hole. A crank 304 is mounted on the top of the threaded rod 303. By shaking the crank 304, the threaded rod 303 rotates, driving the lifting block 305 to move up and down. A deep hole measuring gauge 306 is mounted on the bottom of the lifting block 305. By adjusting the position of the lifting block 305, the probe of the deep hole measuring gauge 306 contacts the outer surface of the capillary.

[0046] A stepper motor 102 is installed on the top of the base 101. The stepper motor 102 drives the capillary to rotate 360° at a speed of 1 rpm through a transmission device. During the rotation of the capillary, the probe of the deep hole measuring gauge 306 keeps in contact with the outer surface of the capillary, and the wall thickness data is collected every 10°. The data is transmitted to the data processing module through a data cable. The data processing module integrates three-dimensional modeling and deviation analysis programs to process the collected data in real time.

[0047] During the entire measurement process, the linkage between the various structures is crucial. The clamping assembly 2 ensures the stable clamping of the capillary through the electric push rod 205 and the clamping block 206. The measuring assembly 3 achieves the precise positioning of the deep hole measuring gauge 306 through the threaded rod 303 and the lifting block 305. The stepper motor 102 drives the rotation of the capillary to ensure the uniform distribution of the measuring points. The data processing module processes the measurement data in real time, generates the wall thickness uniformity model and the wall thickness deviation value, and provides important data support for subsequent production and quality control.

[0048] Example 3: Please refer to Figure 1-Figure 7 In an embodiment of the present invention, a method and device for measuring the wall thickness of an optical fiber capillary are provided, which are used to measure the wall thickness uniformity of an optical fiber capillary with a standard inner hole diameter of 1.0 mm and a length of 50 mm. The specific implementation steps are as follows: 1. Equipment preparation and calibration: A three-claw clamping seat 204 is used to fix a steel wire (diameter 1.0 mm ± 0.005 mm, straightness error ≤ 0.01 mm / m), and a laser calibrator 104 (wavelength 632.8 nm) is used to adjust the parallelism error between the steel wire and the guide rail 103 to ≤ 0.02 mm; The material of the deep hole gauge probe is diamond, with a measurement accuracy of ±0.1 micron and a contact pressure of 0.5 N ±0.1 N; the guide rail 103 adopts a high-precision ball screw structure, with a moving resolution of 1 micron and a repeat positioning accuracy of ±0.5 micron; The stepper motor 102 drives the capillary to rotate at a constant speed of 1 rpm±0.2 rpm, with an angular resolution of 0.1°.

[0049] 2. Measurement process: Capillary pretreatment: Wipe the outer surface of the capillary with anhydrous ethanol to remove oil and dust.

[0050] Wire insertion and fixation: The steel wire is inserted into the inner hole of the capillary tube, and the two ends are clamped by the three-claw clamping seat 204 to ensure that the steel wire is straight and parallel to the slide rail.

[0051] Parameter setting: Enter the standard wall thickness of 0.25 mm (allowable deviation ±2%) in the data processing module, set the segment interval to 2 mm ± 0.5 mm, and the rotation angle interval to 10° ± 2°.

[0052] The stepper motor 102 is started, and the deep hole gauge collects wall thickness data every time the capillary rotates 10° (36 sets of data in a single circle); after each measurement, the guide rail 103 drives the deep hole gauge to move 2 mm axially, and the measurement is repeated until the full length of 50 mm is covered (a total of 25 segmented points).

[0053] Data analysis: The data processing module calculates the wall thickness deviation in real time, generates a wall thickness distribution curve (horizontal axis: axial position 0-50 mm, vertical axis: wall thickness value 240-260 μm) and a three-dimensional uniformity model (resolution 0.01 mm), marking areas with deviations exceeding 2%.

[0054] Result output: Export data files and test reports in CSV format, marking the maximum deviation value (measured +1.8%) and standard deviation (≤0.6 microns).

[0055] The working principle of the embodiment of the present invention is: the diamond probe (±0.1 micron) is combined with the ball screw slide (±0.5 micron) to achieve micron-level repeatability accuracy; the whole process is automatically rotated and data is collected in segments. The measurement of a 50 mm capillary takes about 25 minutes, and the efficiency is improved by 80% compared with manual detection.

[0056] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and alterations may be made to the embodiments without departing from the principles and spirit thereof, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for measuring the wall thickness of an optical fiber capillary, characterized in that: The following steps are involved: Step S1, obtaining a capillary tube to be measured and a steel wire, wherein the diameter of the steel wire meets the matching tolerance of ±0.005 mm with the standard diameter of the inner hole of the capillary tube to be measured, and the straightness error does not exceed 0.01 mm / m, and the steel wire is inserted into the inner hole of the capillary tube to be measured and straightened; Step S2, using a deep hole gauge to perform contact measurement on the outer surface of the capillary to be measured, the measurement accuracy of the probe of the deep hole gauge is ±0.1 micron, and the contact pressure is 0.5 Newton ±0.1 Newton, the deep hole gauge is moved along the slide rail to contact the outer surface of the capillary to be measured, the capillary to be measured is driven to rotate 360 ​​degrees at a speed of 1 revolution per minute, the wall thickness data is collected every 10 degrees, and the full-circle wall thickness data is recorded; Step S3, performing segmented measurement at segment intervals of 2 mm along the axial direction of the capillary to be measured, and repeating step S2 to obtain full-length wall thickness distribution data of the capillary to be measured; Step S4, inputting the measured data into the data processing module, generating a wall thickness uniformity model through a three-dimensional modeling algorithm, and outputting a wall thickness deviation value.

2. The method for measuring the wall thickness of an optical fiber capillary according to claim 1, characterized in that: Before step S1, it also includes: step S0, straightening the steel wire, adjusting the steel wire to be parallel to the deep hole gauge slide rail, and clamping it on a bracket, on which a three-jaw chuck is provided to fix the steel wire to ensure that the steel wire remains stable during the measurement process to avoid measurement errors caused by the shaking of the steel wire, and the clamping surface of the three-jaw chuck is also provided with anti-slip texture.

3. The method for measuring the wall thickness of an optical fiber capillary according to claim 1, characterized in that: In step S2, the probe of the deep hole gauge is made of high-precision ceramic material with a measurement accuracy of ±0.1 micron, and the slide rail is a high-precision linear guide rail with a straightness error of no more than 0.01 mm / m, thereby ensuring that the deep hole gauge remains stable during movement.

4. The method for measuring the wall thickness of an optical fiber capillary according to claim 1, characterized in that: In step S2, the outer surface of the capillary to be measured is cleaned before measurement by wiping with anhydrous ethanol and a clean cotton cloth to remove oil and dust on the surface to ensure the accuracy of the measurement data.

5. The method for measuring the wall thickness of an optical fiber capillary according to claim 4, characterized in that: The data processing module is integrated in an industrial-grade computer, has a built-in 3D modeling algorithm and an automated control program, supports data export formats including CSV, JSON and 3D point cloud files, and generates a wall thickness uniformity model through a 3D modeling algorithm; the calculation formula for the wall thickness deviation value is: wall thickness deviation = ((measured wall thickness - standard wall thickness) / standard wall thickness) × 100%, the standard wall thickness is the theoretical wall thickness of the capillary design, the measured wall thickness is the wall thickness value obtained by actual measurement, and the wall thickness deviation does not exceed 2% of the standard wall thickness.

6. The method for measuring the wall thickness of an optical fiber capillary according to claim 1, characterized in that: The resolution of the wall thickness uniformity model is not less than 0.01 mm, and a wall thickness distribution curve graph can be generated, wherein the abscissa of the curve graph is the axial position of the capillary in millimeters, and the ordinate is the wall thickness value in micrometers.

7. A method for measuring the wall thickness of an optical fiber capillary according to any one of claims 1 to 6, characterized in that: Provided is an optical fiber capillary wall thickness measuring device for measuring the wall thickness of a capillary to be measured, the device comprising: A base (101), wherein a stepping motor (102) is installed on the top of the base (101) for rotating the capillary to be measured, and a guide rail (103) is also installed on the top of the base (101) for moving the top component; A clamping assembly (2), the clamping assembly (2) being mounted on the top of the base (101) and used to fix the capillary to be measured; A measuring component (3), the measuring component (3) being mounted on one side of the clamping component (2) and being used to measure the wall thickness of the capillary; Data processing module, integrating 3D modeling and deviation analysis programs.

8. The optical fiber capillary wall thickness measuring device according to claim 7, characterized in that: The clamping assembly (2) comprises a sliding seat (201) slidably connected to the top of the guide rail (103); a moving frame (202) is installed on the top of the sliding seat (201); a moving seat (203) is slidably connected to the top of the moving frame (202); a three-jaw clamping seat (204) is installed on the bottom of the moving seat (203) and is used for clamping the capillary; an electric push rod (205) is fixedly connected to the inner wall of the three-jaw clamping seat (204); and a clamping block (206) is installed on one side of the electric push rod (205).

9. The optical fiber capillary wall thickness measuring device according to claim 7, characterized in that: The measuring assembly (3) comprises a measuring seat (301) slidably connected to the top of the guide rail (103); a support frame (302) is installed on the top of the measuring seat (301); a threaded hole is opened on the top of the support frame (302); a threaded rod (303) is threadedly connected in the inner cavity of the threaded hole; a crank (304) is installed on the top of the threaded rod (303); a lifting block (305) is installed on the bottom of the threaded rod (303); the threaded rod (303) and the lifting block (305) are rotatably connected via a bearing; and a deep hole measuring gauge (306) is installed on the bottom of the lifting block (305) for measurement.

10. The optical fiber capillary wall thickness measuring device according to claim 7, characterized in that: A laser calibrator (104) is installed on the top of the base (101) for real-time monitoring of the parallelism between the steel wire and the slide rail; the data processing module is electrically connected to the clamping component (2), the measuring component (3) and the laser calibrator (104).

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