A metal pipe inner diameter laser measuring device
By combining the cleaning component and the impurity detection module, the air pressure is dynamically adjusted to remove impurities from the inner wall of metal pipe fittings, solving the problem of detection data deviation and achieving high-precision and high-reliability inner diameter detection.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- JINZHONG UNIV
- Filing Date
- 2026-03-16
- Publication Date
- 2026-05-29
AI Technical Summary
In the inner diameter inspection of metal pipe fittings, impurities such as residual iron filings and cutting fluid on the inner wall affect the laser diameter measurement results, leading to deviations and misjudgments in the test data, which in turn affects product quality control.
The system employs a cleaning component combined with an impurity detection module and an air jet control module. It uses high-pressure gas to clean impurities on the inner wall, and combines image processing and grayscale analysis to accurately determine the type and amount of impurities. It dynamically adjusts the air pressure for cleaning, ensuring detection accuracy and reliability.
It effectively removes impurities from the inner wall, improves detection accuracy and reliability, reduces misjudgments, ensures product quality control, and enhances cleaning efficiency and equipment operating economy.
Smart Images
Figure CN122107962A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of laser measurement technology for inner diameter, and more particularly to a laser measurement device for the inner diameter of metal pipe fittings. Background Technology
[0002] Metal pipe fittings are widely used in many fields such as machinery manufacturing, petrochemicals, pipeline transportation, and automotive industry. The machining accuracy of their inner diameter directly determines the assembly performance, sealing performance and reliability of the pipe fittings. Therefore, after the metal pipe fittings are processed, it is an important process to ensure the machining accuracy, select qualified products, and also a prerequisite for the smooth progress of subsequent assembly operations. Currently, laser diameter measurement technology is widely used for the inner diameter inspection of metal pipe fittings. This technology has advantages such as high detection accuracy, fast response speed, and non-contact measurement, which can effectively avoid scratches on the inner wall of the pipe fitting caused by contact measurement. It has become the mainstream method for inner diameter inspection of metal pipe fittings. However, in the actual production process, during the cutting, grinding and other processing steps of metal pipe fittings, impurities such as iron filings and cutting fluid inevitably remain on the inner wall of the pipe fittings. These impurities will directly affect the detection effect of laser diameter measurement. Iron filings are easy to adhere to the inner wall of the pipe fittings, which will block the laser detection light path, causing the laser to be unable to accurately penetrate and capture the inner diameter signal, resulting in problems such as detection data deviation and misjudgment. The residual cutting fluid will form a thin film, which will not only interfere with the reflection and reception of the laser, but may also mix with iron filings to form a viscous deposit, further aggravating the detection error, causing qualified pipe fittings to be misjudged as unqualified, or unqualified pipe fittings to flow into the next process, seriously affecting product quality control. Therefore, improvements are needed to address the aforementioned issues. Summary of the Invention
[0003] The purpose of this invention is to address the shortcomings of existing technologies by proposing a laser measuring device for the inner diameter of metal pipe fittings.
[0004] To achieve the above objectives, the present invention adopts the following technical solution: a laser measuring device for the inner diameter of metal pipe fittings. The machine includes a machine base. Two guide rails are symmetrically arranged on one end of the top surface of the machine base. A slider is slidably connected to each of the two guide rails. A linear motor is arranged between the two guide rails. The slider and the moving part of the linear motor are fixedly connected to a mounting plate by bolts. An electric chuck is fixedly connected to the top surface of the mounting plate. A bracket is fixedly connected to the other end of the top surface of the machine base. An electric push cylinder is fixedly connected to the top surface of the bracket. A laser diameter measuring instrument is fixedly connected to the telescopic end of the electric push cylinder. The laser diameter measuring instrument is coaxially arranged with the electric chuck. A cleaning component for cleaning the inner wall of metal pipes is fixedly connected to the end of the laser diameter measuring instrument away from the electric push cylinder. The machine is equipped with a control console at one end of the top surface near the laser diameter measuring instrument. The control console contains an impurity judgment module and an air jet control module. The impurity determination module calculates the grayscale value fluctuation range after grayscale conversion and block processing of the acquired image, marks outliers and removes them to determine the image for analysis; it identifies abnormal grayscale blocks within the pipe fitting outline, compares them with historical grayscale ranges to determine the type of impurity, and estimates the weight of various impurities by combining parameters such as area and density. The jet control module determines the jet pressure by comparing the total weight of impurities with a preset threshold: if the weight is below the minimum threshold, the minimum effective pressure is used; if the weight is between the thresholds, the pressure is linearly adjusted; if the weight is above the maximum threshold, the maximum safe pressure is used. The minimum effective pressure is calculated by a basic formula that includes parameters such as impurity adhesion, pipe diameter, and airflow loss.
[0005] Preferably, the data analysis steps of the impurity determination module are as follows: M1: The image of the pipe end captured by the camera is converted to grayscale and divided into several grayscale blocks according to a preset size. Each grayscale block is numbered. For grayscale blocks acquired at the same time, multiple grayscale values are obtained and their mean and standard deviation are calculated. A grayscale value fluctuation range is set, and grayscale values exceeding this range are marked as outliers, and the number of outliers is counted. ;like If the grayscale data at that moment is deemed abnormal, it will be re-acquired. This is a preset proportional coefficient. The total number of grayscale values; otherwise, the mean of the remaining grayscale values is calculated after removing outliers. The grayscale value of the grayscale block is used as the grayscale value; if the grayscale block is still abnormal after multiple re-examinations, it is determined to be abnormal. M2: After completing the identification of all grayscale blocks, record the number of abnormal grayscale blocks in each image. Select The smallest image is used as the analysis image; the gray values of gray blocks in the analysis image are randomly selected and compared with the preset gray range of pipe fittings to identify all gray blocks within the pipe fitting outline; anomaly detection is performed on the gray blocks within the pipe fitting outline, the number of abnormal gray blocks is counted, and the area of a single gray block is calculated based on the distance between the camera and the pipe fitting. Compare the abnormal grayscale blocks with the grayscale ranges of iron filings and cutting fluid in historical data to determine whether the impurity type is iron filings, cutting fluid, or stains; and determine the number of grayscale blocks corresponding to the impurity type. ,area ,density and adhesion thickness coefficient According to the formula Estimate the weight of various impurities.
[0006] Preferably, the data analysis steps of the jet control module are as follows: Q1: Obtain the estimated weights of iron filings, cutting fluid, and contaminants from the impurity detection module, and calculate the total weight of impurities. ;Will Compared with the preset minimum threshold and highest threshold Comparison: If At that time, jet pressure ;like At that time, jet pressure , This is the air pressure regulation coefficient; if At that time, jet pressure , Maximum safe air pressure; Q2: Minimum effective air pressure Calculated using the following formula: ,in The base pressure correction factor and These are weighting coefficients. The basic adhesion coefficient is the impurity. This is the airflow loss coefficient for the rotating nozzle. The inner diameter of the metal pipe fitting. This refers to the effective delivery length of the intake pipe.
[0007] Preferably, a laser rangefinder sensor for detecting the position of the end of the metal pipe is installed at an angle on one side of the machine.
[0008] Preferably, the cleaning assembly includes a base fixed to one end of a laser diameter gauge, and an internally threaded ring is rotatably connected to the end of the base away from the laser diameter gauge via a bearing. A rotating nozzle is screwed into the internally threaded ring.
[0009] Preferably, an air inlet pipe is screwed onto one side of the outer wall of the base, and one end of the air inlet pipe is connected to an air compressor fixed to the upper middle part of the bracket.
[0010] Preferably, the rotating nozzle has a conical cylindrical shape, and one section of the air intake pipe is a corrugated pipe.
[0011] Preferably, the grippers of the electric chuck are fitted with anti-slip rubber sleeves.
[0012] Compared with the prior art, the beneficial effects of the present invention are: 1. By cooperating with the air compressor and air inlet pipe in the cleaning component, high-pressure gas can be delivered to the base, providing sufficient power for impurity removal and improving the convenience and thoroughness of cleaning. This enables a stable supply of high-pressure gas, laying the foundation for cleaning the inner wall. Furthermore, through the cooperation of the base, internal threaded ring, and rotating nozzle, the high-pressure gas drives the rotating nozzle to rotate and spray, performing a comprehensive cleaning of the inner wall of the metal pipe. This facilitates the removal of residual iron filings, cutting fluid, and other impurities, improving the cleanliness of the inner wall. This allows for comprehensive cleaning of the pipe's inner wall and prevents impurities from obstructing the laser beam path. Ultimately, this solves the problem of residual impurities on the inner wall of metal pipes causing deviations in laser diameter measurement data, improving detection accuracy and reliability, reducing misjudgments, and ensuring effective product quality control. 2. By processing the image of the pipe end through the impurity judgment module and comparing it with the grayscale range of iron filings and cutting fluid in historical data, the type of impurity is accurately determined. Combined with the grayscale block area, impurity density and adhesion thickness coefficient, the weight of various impurities is quantitatively estimated. This solves the blind spot problem of traditional cleaning methods being unable to detect the type and quantity of impurities, provides an accurate data basis for the subsequent adaptive control of air pressure, avoids laser detection optical path obstruction and detection errors caused by impurity residue, and improves detection reliability and product quality control level. 3. The jet control module compares the total weight of impurities estimated by the impurity judgment module with a preset threshold and dynamically selects the minimum effective air pressure, linearly adjusts the air pressure, or sets the maximum safe air pressure. This solves the problem of insufficient cleaning or energy waste caused by the fixed air pressure in traditional cleaning methods. It achieves on-demand air supply and precise cleaning, which not only ensures the cleaning effect but also avoids damage to pipes and energy waste caused by excessive air pressure, significantly improving cleaning efficiency and equipment operating economy. Attached Figure Description
[0013] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a first-view schematic diagram of the overall structure proposed in this invention; Figure 2 This is a schematic diagram of the overall structure of the support proposed in this invention; Figure 3 This is a schematic diagram of the overall structure of the laser ranging sensor proposed in this invention; Figure 4 This is a schematic diagram of the overall structure of the base proposed in this invention; Figure 5 This is a flowchart of the system proposed in this invention.
[0014] The numbers in the diagram are: 1. Machine base; 2. Guide rail; 3. Linear motor; 4. Mounting plate; 5. Electric chuck; 6. Bracket; 7. Electric push cylinder; 8. Laser diameter gauge; 9. Laser rangefinder sensor; 10. Air inlet pipe; 11. Air compressor; 12. Base; 13. Control console; 14. Rotary nozzle. Detailed Implementation
[0015] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.
[0016] Example 1: See Figures 1 to 4 A laser measuring device for the inner diameter of metal pipe fittings according to the present invention The machine includes a base 1. Two guide rails 2 are symmetrically arranged on one end of the top surface of the base 1. A slider is slidably connected to each guide rail 2. A linear motor 3 is located between the two guide rails 2. The slider and the mover of the linear motor 3 are bolted together to a mounting plate 4. An electric chuck 5 is fixed to the top surface of the mounting plate 4. A bracket 6 is fixed to the other end of the top surface of the base 1. An electric push cylinder 7 is fixed to the top surface of the bracket 6. A laser diameter gauge 8 is fixed to the telescopic end of the electric push cylinder 7. The laser diameter gauge 8 is coaxially arranged with the electric chuck 5. A cleaning component for cleaning the inner wall of metal pipes is fixed to the end of the laser diameter gauge 8 furthest from the electric push cylinder 7. The base 1 is made of Q235 steel plate. The Q235 steel plate used in the base 1 provides high structural strength and load-bearing capacity, ensuring stable support for the operation of all components. The guide rail 2 is made of HT200 gray cast iron, which has good wear resistance and high guiding accuracy, ensuring smooth sliding of the slider. The linear motor 3 is a CFB series servo linear motor, which runs smoothly and positions accurately, and can drive the mounting plate 4 to move precisely. The mounting plate 4 is made of 45# steel, which has high hardness and a robust structure, and can stably install the electric chuck 5. The electric chuck 5 is a four-jaw electric chuck, which has a wide clamping range and firm clamping, and can stably fix metal pipe fittings. The bracket 6 is made of stainless steel, which is corrosion resistant and has a strong load-bearing capacity, and can stably support the electric push cylinder 7 and the air compressor 11. The electric push cylinder 7 is a DK series electric cylinder, which has smooth extension and retraction and precise positioning, and can carry... The laser diameter gauge 8 moves precisely; the laser diameter gauge 8 adopts the ZID100 laser diameter gauge, which has high detection accuracy and fast response, and can accurately capture the inner diameter of metal pipes; the machine base 1 provides a stable installation foundation for the entire device, ensuring the orderly assembly of each component; the guide rail 2 cooperates with the slider to provide guidance for the movement of the mounting plate 4, ensuring smooth movement; the linear motor 3 provides power for the movement of the mounting plate 4, realizing the precise positioning of the electric chuck 5 and the metal pipes; the mounting plate 4 realizes the stable installation of the electric chuck 5, ensuring clamping stability; the electric chuck 5 can firmly clamp the metal pipes, avoiding pipe displacement during the detection process; the bracket 6 provides stable support for components such as the electric push cylinder 7 and the laser diameter gauge 8; the electric push cylinder 7 drives the laser diameter gauge 8 to move. The device features a telescopic detection end; a laser diameter gauge 8 enables precise detection of the inner diameter of metal pipe fittings; a cleaning component removes impurities from the inner wall of the pipe fittings, preventing interference with detection; these components together form the basic framework of the device, providing stable structural support for the entire process of clamping, positioning, cleaning, and detection of metal pipe fittings, and initially solving the problem of impurities interfering with the detection accuracy of traditional detection devices; a laser rangefinder 9 is installed at an angle on one side of the machine base 1 to detect the position of the end of the metal pipe fitting; the laser rangefinder 9 uses an OADM laser rangefinder sensor, which has a wide detection range, fast response, and can accurately detect the position of the end of the metal pipe fitting; the laser rangefinder 9 is fixed to one side of the machine base 1 by a stainless steel bracket, and the bracket structure is sturdy, ensuring stable sensor detection;The laser rangefinder 9 can detect the end position of the metal pipe in real time and promptly feed back the positioning signal to ensure the linear motor 3 stops accurately, achieving precise positioning of the metal pipe. This avoids optical path deviation caused by pipe positional deviation, improving positioning accuracy and detection reliability, and thus ensuring the smooth progress of subsequent inspection work. A control console 13 is located at one end of the machine base near the top surface of the laser diameter gauge 8. The control console 13 has a touch screen for easy parameter setting and data viewing. Its outer shell is made of cold-rolled steel plate, providing good protection. The control console 13 can adjust equipment parameters, control the start and stop of various components, and simultaneously receive detection data from the laser diameter gauge 8 for data processing, display, and judgment, screening qualified and unqualified products. This improves the convenience and efficiency of the inspection operation, allowing operators to monitor the equipment's operating status and inspection results in real time.
[0017] In this invention, the cleaning assembly includes a base 12 fixedly connected to one end of a laser diameter gauge 8. The end of the base 12 furthest from the laser diameter gauge 8 is rotatably connected to an internally threaded ring via a bearing. A rotating nozzle 14 is screwed into the internally threaded ring. An air inlet pipe 10 is screwed onto one side of the outer wall of the base 12. One end of the air inlet pipe 10 is connected to an air compressor 11 fixed to the upper middle part of a bracket 6. The base 12 is made of brass, which is tough, has good sealing properties, and can stably deliver high-pressure gas. The internally threaded ring is made of 45# steel, with high thread precision, allowing for a secure connection with the rotating nozzle 14. The nozzle 14 uses a three-eye stainless steel automatic rotary nozzle, which is corrosion-resistant and not easily clogged, enabling uniform spraying of high-pressure gas. The air inlet pipe 10 uses a PU flexible hose, which is flexible and has strong sealing properties, ensuring stable delivery of high-pressure gas. The air compressor 11 uses a GY series silent air compressor, which provides stable gas production and sufficient pressure, providing a continuous supply of high-pressure gas. The base 12 provides an installation foundation for all components of the cleaning assembly, ensuring stable gas delivery. The bearing enables flexible rotation of the internal threaded ring, driving the rotary nozzle 14 to rotate synchronously. The rotary nozzle 14 can spray high-pressure gas from all directions onto the inner wall of the pipe, achieving the removal of impurities. Thorough cleaning; the air inlet pipe 10 ensures stable delivery of high-pressure gas, and the air compressor 11 provides sufficient power for cleaning operations, achieving automatic cleaning of the inner wall of the metal pipe fittings, preventing impurities from obstructing the laser beam path, and improving detection accuracy; the rotating nozzle 14 has a conical cylindrical shape, and one section of the air inlet pipe 10 is a corrugated pipe; the conical cylindrical rotating nozzle 14 allows high-pressure gas to be blown forward and evenly cover the inner wall of the pipe fittings, while preventing impurities from falling onto the probe of the laser diameter gauge 8; the corrugated pipe can flexibly adapt to the movement of the laser diameter gauge 8 and the base 12, avoiding pipe pulling damage and ensuring continuous gas delivery. The continuous operation further improves the stability and reliability of cleaning operations. The jaws of the electric chuck 5 are fitted with anti-slip rubber sleeves. These sleeves are made of nitrile rubber, which is flexible, has high friction, provides excellent anti-slip performance, and is less likely to scratch the outer wall of metal pipes. The anti-slip rubber sleeves are precisely matched with the jaws of the electric chuck 5, ensuring a secure installation and preventing them from easily falling off. The anti-slip rubber sleeves increase the friction between the jaws and the metal pipes, preventing the pipes from sliding or shifting during clamping and inspection, thus improving clamping stability. Simultaneously, they protect the outer wall of the metal pipes, preventing the jaws from scratching them, ensuring the pipes remain in good condition, and reducing product loss.
[0018] Working principle: In the use of this invention, the operator places the metal pipe to be inspected on the electric chuck 5. The jaws of the electric chuck 5 are fitted with anti-slip rubber sleeves to stably clamp the pipe and prevent it from sliding or scratching the outer wall during clamping. After clamping, the linear motor 3 starts, driving its mover and the slider and mounting plate 4 fixed to the mover to slide along the guide rail 2, thereby driving the electric chuck 5 and the metal pipe to move synchronously until the laser rangefinder 9 detects that the end of the metal pipe is in place. The linear motor 3 then stops running, completing the positioning of the pipe. Subsequently, the air compressor 11 starts. High-pressure gas is delivered to the base 12 of the cleaning component through the air inlet pipe 10. The corrugated section of the air inlet pipe 10 can flexibly adapt to the movement of the base 12 to avoid damage to the pipe by pulling. After the high-pressure gas enters the base 12, it drives the internal threaded ring connected to the base 12 through the bearing to rotate, which in turn drives the rotating nozzle 14 screwed in the internal threaded ring to rotate synchronously. The rotating nozzle 14 is a conical column shape, which can spray the high-pressure gas evenly and omnidirectionally onto the inner wall of the metal pipe to blow away the iron filings, cutting fluid and other impurities remaining on the inner wall, so as to avoid impurities blocking the laser beam path and interfering with the detection results. After cleaning is completed, the electric push cylinder 7 is activated to move the laser diameter gauge 8, which is fixed to its telescopic end, toward the metal pipe fitting until the detection end of the laser diameter gauge 8 extends into the pipe fitting. Since the laser diameter gauge 8 and the electric chuck 5 are coaxially set, it can ensure that the detection optical path is consistent with the center line of the inner diameter of the pipe fitting. The laser diameter gauge 8 is activated, emits laser and receives reflected signals, accurately captures the inner diameter data of the metal pipe fitting, and transmits the detection data to the control console 13 in real time. The control console 13 processes, displays and judges the data, and filters out qualified and unqualified products. At this point, the use of the device is completed.
[0019] Example 2: See Figure 5 The control console 13 is equipped with an impurity detection module and a jet control module. The impurity detection module acquires images, converts them to grayscale, and divides them into blocks. It calculates the mean and standard deviation of the grayscale values of each grayscale block, sets the fluctuation range, and marks outliers. If the proportion of outliers exceeds the standard, the image is re-examined; otherwise, outliers are removed, and the mean is recalculated as the grayscale value of the block. If there are multiple outliers, the block is determined to be abnormal. Finally, the image with the fewest outlier blocks is selected as the analysis image. The module identifies grayscale blocks within the pipe fitting outline based on the grayscale range of the pipe fitting, counts the number of outlier blocks, and calculates the area of a single grayscale block based on the distance between the pipe fitting and the camera. The module compares the grayscale range of the outlier blocks with that of iron filings and cutting fluid in historical data to determine the type of impurity. It also estimates the weight of various impurities based on the number, area, density, and adhesion thickness coefficient of the impurity blocks. The jet control module calculates the total weight of impurities based on the weights of various impurities estimated by the impurity judgment module. It then compares this total weight with preset minimum and maximum thresholds: if the weight is below the minimum threshold, the jet pressure is set to the minimum effective pressure; if it is between the two thresholds, the pressure is linearly adjusted based on the weight difference of the impurities and the pressure adjustment coefficient, while if the weight is above the maximum threshold, the maximum safe pressure is applied. The calculation of the minimum effective pressure comprehensively considers the impurity adhesion coefficient, pipe inner diameter, airflow loss coefficient, inlet pipe length, weighting coefficient, and correction coefficient. These parameters are obtained through experimental calibration, real-time calculation, and regression analysis. After the laser rangefinder 9 detects that the end of the metal pipe is in place, the image data of the pipe is acquired by the camera (the camera is facing the end of the pipe and only acquires the circular outline image of the pipe) set at the position of the electric push cylinder 7 on the upper surface of the bracket 6. The real-time acquired image data is processed into grayscale, and the grayscale image is segmented according to the size of pixel blocks, resulting in... The image data consists of several identical grayscale blocks, numbered according to their row and column numbers on the grayscale image. The acquired image data is sorted by acquisition time, and the corresponding numbered grayscale blocks within a single image acquired at the same time are further analyzed. Average the gray values and standard deviation The calculation, and the mean obtained from the calculation. and standard deviation Range of grayscale data The setting compares the corresponding grayscale value data with the corresponding grayscale value fluctuation range, marks the corresponding grayscale value data that is outside the fluctuation range as an outlier, and records the number of outliers. ; like If the grayscale data is abnormal, the grayscale data will be detected again. This is a preset proportional coefficient; if If outliers are removed, the remaining grayscale data after outlier removal is averaged. The calculation, and the mean obtained from the calculation. This serves as the grayscale value data detected at the corresponding time. If, upon re-detection, the grayscale value data is still deemed abnormal, then the corresponding numbered grayscale block is determined to be abnormal. After determining the grayscale values of all numbered grayscale blocks on the grayscale image, the number of abnormal grayscale blocks is calculated. Record and take the quantity The image with the smallest grayscale value is the image to be analyzed; Randomly select a grayscale block with an arbitrary number on the analysis image and compare its grayscale value with the grayscale value range of the pipe fitting. If the grayscale value of the corresponding grayscale block is within the grayscale value range of the pipe fitting, then the grayscale block is determined to be a pipe fitting grayscale block. Traverse all pipe fitting grayscale blocks on the analysis image and draw the pipe fitting outline on the analysis image according to the number of the pipe fitting grayscale block. Anomalies are identified in the grayscale values of grayscale blocks within the pipe fitting outline, and the number of abnormal grayscale blocks is counted. The area of each grayscale block is calculated based on the distance between the pipe fitting and the camera. Get the total area of abnormal grayscale blocks inside the pipe fitting outline; get historical image analysis data, retrieve the grayscale range of iron filings and cutting fluid in the historical image analysis data according to the results, and compare it with the corresponding abnormal grayscale blocks inside the pipe fitting outline to determine whether it is iron filings or cutting fluid. If it is not either of the above, it is determined to be a stain. Based on the area of a single grayscale block and the number of gray blocks corresponding to the impurity type , , Estimate the weight data of the corresponding impurities. , This represents the total number of abnormal grayscale blocks corresponding to the impurities. The density of the corresponding impurities, This is the coefficient for the thickness of impurity adhesion. Historical operational data shows that when the impurity weight is below the minimum value... At this point, continuing to reduce the jet pressure will not achieve the desired cleaning effect; record the pressure at this time. When the weight of impurities is higher than the maximum value At this point, continuing to increase the air pressure will result in wasted resources and damage to the pipes. Record the air pressure at this time. Therefore, the total weight of the three types of impurities inside the pipe fitting is obtained. At that time, jet pressure ;exist At that time, jet pressure , This is the barometric pressure regulation coefficient; in At that time, jet pressure ; ,in The base pressure correction factor and These are weighting coefficients. The basic adhesion coefficient is the impurity. This is the airflow loss coefficient for the rotating nozzle. The inner diameter of the metal pipe fitting. This refers to the effective delivery length of the intake pipe; Collect a large amount of experimental data (different) , , , Optimal Clean Air Pressure Substitute the data into the formula and fit the result using the least squares method or other regression methods. and Beforehand, the adhesion forces of three typical impurities on the inner wall of a standard pipe fitting were determined through tensile / shear force tests, and the results were normalized to obtain a baseline value. During equipment operation, the current air pressure is calculated by comparing the output air pressure of the air compressor with the actual output air pressure of the nozzle in real time. , and These are the air pressures at the nozzle inlet and outlet, respectively. Given these parameters, an experiment is set up, and a cleaning test is conducted using fittings with known parameters to determine the actual required air pressure. The derivation yields .
[0020] 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 laser measuring device for the inner diameter of metal pipe fittings, comprising a machine base (1), two guide rails (2) symmetrically arranged at one end of the top surface of the machine base (1), a slider slidably connected on each of the two guide rails (2), a linear motor (3) arranged between the two guide rails (2), and a mounting plate (4) fixedly connected to the slider and the moving part of the linear motor (3) by bolts, and an electric chuck (5) fixedly connected to the top surface of the mounting plate (4), characterized in that: A bracket (6) is fixed to the other end of the top surface of the machine base (1). An electric push cylinder (7) is fixed to the top surface of the bracket (6). A laser diameter measuring instrument (8) is fixed to the telescopic end of the electric push cylinder (7). The laser diameter measuring instrument (8) is coaxially arranged with the electric chuck (5). A cleaning component for cleaning the inner wall of metal pipe fittings is fixed to the end of the laser diameter measuring instrument (8) away from the electric push cylinder (7). The machine (1) is equipped with a control console (13) at one end of the top surface near the laser diameter measuring instrument (8). The control console (13) is equipped with an impurity judgment module and an air jet control module. The impurity determination module calculates the grayscale value fluctuation range after grayscale conversion and block processing of the acquired image, marks outliers and removes them to determine the image for analysis; it identifies abnormal grayscale blocks within the pipe fitting outline, compares them with historical grayscale ranges to determine the type of impurity, and estimates the weight of various impurities by combining parameters such as area and density. The jet control module determines the jet pressure by comparing the total weight of impurities with a preset threshold: if the weight is below the minimum threshold, the minimum effective pressure is used; if the weight is between the thresholds, the pressure is linearly adjusted; if the weight is above the maximum threshold, the maximum safe pressure is used. The minimum effective pressure is calculated by a basic formula that includes parameters such as impurity adhesion, pipe diameter, and airflow loss.
2. The laser measuring device for the inner diameter of metal pipes according to claim 1, characterized in that: The data analysis steps for the impurity detection module are as follows: M1: The image of the pipe end captured by the camera is converted to grayscale and divided into several grayscale blocks according to a preset size. Each grayscale block is numbered. For grayscale blocks acquired at the same time, multiple grayscale values are obtained and their mean and standard deviation are calculated. A grayscale value fluctuation range is set, and grayscale values exceeding this range are marked as outliers, and the number of outliers is counted. ;like If the grayscale data at that moment is deemed abnormal, it will be re-acquired. This is a preset proportional coefficient. The total number of grayscale values; otherwise, the mean of the remaining grayscale values is calculated after removing outliers. The grayscale value of the grayscale block is used as the grayscale value; if the grayscale block is still abnormal after multiple re-examinations, it is determined to be abnormal. M2: After completing the identification of all grayscale blocks, record the number of abnormal grayscale blocks in each image. Select The smallest image is used as the analysis image; the gray values of gray blocks in the analysis image are randomly selected and compared with the preset gray range of pipe fittings to identify all gray blocks within the pipe fitting outline; anomaly detection is performed on the gray blocks within the pipe fitting outline, the number of abnormal gray blocks is counted, and the area of a single gray block is calculated based on the distance between the camera and the pipe fitting. Compare the abnormal grayscale blocks with the grayscale ranges of iron filings and cutting fluid in historical data to determine whether the impurity type is iron filings, cutting fluid, or stains; and determine the number of grayscale blocks corresponding to the impurity type. ,area ,density and adhesion thickness coefficient According to the formula Estimate the weight of various impurities.
3. The laser measuring device for the inner diameter of metal pipe fittings according to claim 2, characterized in that: The data analysis steps for the jet control module are as follows: Q1: Obtain the estimated weights of iron filings, cutting fluid, and contaminants from the impurity detection module, and calculate the total weight of impurities. ;Will Compared with the preset minimum threshold and highest threshold Comparison: If At that time, jet pressure ;like At that time, jet pressure , This is the air pressure regulation coefficient; if At that time, jet pressure , Maximum safe air pressure; Q2: Minimum effective air pressure Calculated using the following formula: ,in The base pressure correction factor and These are weighting coefficients. The basic adhesion coefficient is the impurity. This is the airflow loss coefficient for the rotating nozzle. The inner diameter of the metal pipe fitting. This refers to the effective delivery length of the intake pipe.
4. The laser measuring device for the inner diameter of metal pipe fittings according to claim 1, characterized in that: A laser rangefinder (9) for detecting the position of the end of a metal pipe is installed at an angle on one side of the machine (1).
5. A laser measuring device for the inner diameter of metal pipe fittings according to claim 1 Its features are: The cleaning assembly includes a base (12) fixed to one end of the laser diameter gauge (8). The end of the base (12) away from the laser diameter gauge (8) is rotatably connected to an internal threaded ring via a bearing. A rotating nozzle (14) is screwed into the internal threaded ring.
6. A laser measuring device for the inner diameter of metal pipe fittings according to claim 5. Its features are: An air inlet pipe (10) is screwed onto one side of the outer wall of the base (12), and one end of the air inlet pipe (10) is connected to an air compressor (11) fixed to the upper middle part of the bracket (6).
7. A laser measuring device for the inner diameter of metal pipes according to claim 6. Its features are: The rotating nozzle (14) has a conical cylindrical shape, and one section of the air inlet pipe (10) is a corrugated pipe.
8. A laser measuring device for the inner diameter of metal pipes according to claim 1 Its features are: The jaws of the electric chuck (5) are fitted with anti-slip rubber sleeves.