Laser measuring device for outer diameter of plastic pipe

Abstract

The utility model discloses a plastic pipe external diameter laser measuring device, which comprises a spacing-adjustable supporting wheel, a rotation driving mechanism and a double-laser measuring head assembly, the supporting wheel adopts a V-shaped rubber rim structure to prevent axial displacement and surface scratch of a pipe, a rotation disc triggers a laser head through a magnetic encoder to acquire data at an equal angle interval of 0.1 degree, and the rotation driving mechanism is connected with the double-laser measuring head assembly. High-density uniform sampling is realized by combining closed-loop control of a servo motor; the three-axis measuring platform is provided with an electric adjusting mechanism, the laser head is automatically adjusted to the optimal focusing distance according to the initial measuring value, and the data processor dynamically optimizes the sampling frequency and calculates the ellipticity deviation. The device has the advantages that the influence of rotating speed fluctuation is eliminated through an angle triggering mode, the V-shaped supporting structure is matched with a DN 20-300 mm pipe, high-precision nondestructive measurement is guaranteed through a rubber protection layer and an automatic focusing mechanism, and the device is suitable for rapid detection of a continuous production line.

Description

Technical Field

[0001] This utility model relates to the field of non-contact precision testing of tubular workpieces, and in particular to a laser measuring device for the outer diameter of plastic pipes. Background Technology

[0002] PVC plastic pipes are essential materials in building water supply and drainage, municipal engineering, and other fields. The accuracy of their outer diameter directly affects the pipe's sealing performance, connection reliability, and service life. Traditional measurement methods, often using contact calipers or micrometers for manual sampling, have the following drawbacks:

[0003] 1. Low efficiency: Manual point-by-point measurement is time-consuming and difficult to achieve continuous circumferential inspection, easily overlooking local deformations or ellipticity deviations; 2. Risk of surface damage: Contact tools are prone to scratching the surface of PVC pipes, affecting appearance quality and corrosion resistance; 3. Insufficient adaptability: Fixed support structures cannot adapt to pipes of different diameters, requiring frequent clamp changes and increasing operational complexity; 4. Low data acquisition density: Existing rotary measuring devices mostly use fixed time interval sampling, which leads to uneven data distribution when the pipe rotation speed fluctuates, affecting the accuracy of ellipticity and concentricity calculations.

[0004] In recent years, non-contact laser measurement technology has been gradually applied to pipe inspection. However, existing equipment still suffers from problems such as poor anti-slip performance of the support mechanism, fixed focusing distance of the measuring head, and inability to dynamically adjust the sampling frequency, making it difficult to meet the high-precision and high-efficiency industrial measurement requirements. Therefore, there is an urgent need for a measuring device that combines adaptive adjustment, high-precision data acquisition, and surface protection functions. Utility Model Content

[0005] The technical problem to be solved by this utility model is to overcome the defects of the prior art and provide a laser measuring device for the outer diameter of plastic pipes.

[0006] To solve the above-mentioned technical problems, this utility model provides the following technical solution:

[0007] This utility model discloses a laser measuring device for the outer diameter of plastic pipes, comprising: a support assembly including a worktable, two parallel guide rails disposed on the worktable, and at least a pair of adjustable-pitch support wheels slidably connected to the guide rails. The support wheels are connected to the guide rails via a position adjustment slide and are equipped with adjustment rollers to adapt to pipes of different diameters; and a rotary drive assembly disposed at one end of the support assembly, including a fixed base, a rotary disk mounted on the side of the fixed base, a drive motor for driving the rotary disk to rotate, a horizontal position detection switch for detecting the horizontal position of the pipe, and an angle sensing switch. The drive motor transmits power via gears or belts. The rotating disk is dynamically connected; the measuring components include two opposing laser measuring heads, a triaxial measuring platform for fixing the laser measuring heads, and a data processor. The optical path of the laser measuring head is perpendicular to the pipe axis, and its distance from the pipe surface is adjusted by the triaxial measuring platform. The support wheel has a V-shaped rim and is covered with a rubber layer to limit the axial displacement of the pipe and reduce surface scratches. The angle sensing switch is a magnetic or photoelectric encoder. When the rotating disk rotates to a set angle, it triggers the laser measuring head to collect data at equal angular intervals, extracting one valid data point every 0.1°.

[0008] As a preferred technical solution of this utility model, the wavelength of the laser measuring head is 850-1550nm, the measurement frequency is 100-500Hz, and the data processor dynamically adjusts the sampling interval according to the real-time rotation speed of the rotary table to ensure that at least 3 data points are collected for every 1° rotation.

[0009] As a preferred technical solution of this utility model, the horizontal position detection switch is a photoelectric sensor or a mechanical limit switch. When the pipe is detected to be offset from the center of the turntable by more than ±2mm, an audible and visual alarm is triggered and the drive motor is paused.

[0010] As a preferred technical solution of this utility model, the triaxial measurement platform is equipped with an electric adjustment mechanism, which is connected to a data processor and automatically adjusts the distance between the laser measuring head and the surface of the pipe to the optimal focusing range according to the initial measurement value of the outer diameter of the pipe.

[0011] As a preferred technical solution of this utility model, the drive motor is a servo motor, and its rotation speed and the sampling frequency of the laser measuring head are controlled in a closed loop by a data processor to ensure that the measurement data is evenly distributed during the rotation of the pipe.

[0012] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0013] 1. High-precision full-circumference measurement: The laser measuring head is triggered by an angle sensing switch to collect data every 0.1°. Combined with the closed-loop control of the servo motor, the data points are evenly distributed, and the ellipticity of the pipe (error ≤ 0.05mm) and the outer diameter deviation can be accurately calculated. The three-axis measuring platform is equipped with an electric adjustment mechanism, which automatically optimizes the laser head focusing distance according to the initial measurement value to eliminate the measurement error caused by defocusing.

[0014] 2. Highly adaptable to different pipe materials: The adjustable spacing support wheel and V-shaped rubber rim design can adapt to PVC pipes in the range of DN20-DN300mm. The adjustment time is less than 1 minute, and the rubber layer effectively prevents scratches on the pipe surface; the horizontal position detection switch monitors the pipe offset in real time (threshold ±2mm) to avoid measurement distortion caused by eccentric rotation.

[0015] 3. Intelligent operation and protection: The data processor dynamically adjusts the sampling frequency (100-500Hz) to ensure that at least 3 data points are collected for every 1° of rotation, adapting to speed fluctuations; the audible and visual alarm system is linked with the motor emergency stop to prevent equipment damage caused by pipe misalignment or unstable support. Attached Figure Description

[0016] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings:

[0017] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0018] Figure 2 This is the front view of this utility model;

[0019] Figure 3 This is a top view of the present invention;

[0020] Figure 4 This is a side view of the present invention;

[0021] In the diagram: 1. Support assembly; 2. Rotary drive assembly; 3. Measuring assembly; 11. Worktable; 12. Guide rail; 13. Support wheel; 14. Position adjustment slide; 15. Adjustment roller; 21. Fixed base; 22. Turntable; 23. Drive motor; 24. Horizontal position detection switch; 25. Angle sensing switch; 31. Laser measuring head; 32. Triaxial measuring platform; 33. Data processor; 34. Electric adjustment mechanism; 133. Rubber layer. Detailed Implementation

[0022] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0023] In the attached diagram, all identical reference numerals refer to the same components.

[0024] like Figure 1-4 As shown, this utility model provides a laser measuring device for the outer diameter of plastic pipes, comprising the following main structure:

[0025] The support assembly 1 includes a worktable 11, two parallel guide rails 12, at least one pair of adjustable spacing support wheels 13, a position adjustment slide 14, and adjustment rollers 15. The worktable 11 is a rectangular steel plate structure, with two parallel guide rails 12 fixedly installed on top. The extension direction of the guide rails 12 is parallel to the axis of the pipe.

[0026] The adjustable spacing support wheel 13 is slidably connected to the guide rail 12 via the position adjustment slide 14. The adjustment roller 15 is installed on the side of the position adjustment slide 14. Manually rotating the adjustment roller 15 can drive the support wheel 13 to move synchronously along the guide rail 12, thereby adapting to pipes of different diameters.

[0027] The rim of the support wheel 13 has a V-shaped structure and is covered with a rubber layer. The V-shaped groove is used to limit the axial displacement of the pipe, and the rubber layer avoids hard contact with the PVC pipe, which would cause surface scratches.

[0028] The rotary drive assembly 2 is located at one end of the support assembly 1 and includes a fixed base 21, a rotary disk 22, a drive motor 23, a horizontal position detection switch 24, and an angle sensing switch 25.

[0029] The fixed base 21 is fixed to the end of the workbench 11 by bolts, and a rotary table 22 is installed on its side. The central axis of the rotary table 22 coincides with the axis of the pipe after it is placed.

[0030] The drive motor 23 is connected to the rotary table 22 through a gear or belt transmission mechanism, driving the rotary table 22 to rotate the pipe around the axis at a uniform speed; the horizontal position detection switch 24 is a photoelectric sensor, installed on the edge of the rotary table 22, used to detect the horizontal offset of the pipe. When the offset exceeds the set threshold, it triggers an audible and visual alarm and cuts off the power to the drive motor 23.

[0031] The angle sensing switch 25 is a magnetic encoder embedded in the rotating shaft of the rotary table 22. When the rotary table 22 rotates to every 0.1° angle, it sends a trigger signal to the measuring component 3.

[0032] The measurement component 3 includes two laser measuring heads 31, a triaxial measuring platform 32, a data processor 33, and an electric adjustment mechanism 34.

[0033] The laser measuring head 31 is symmetrically arranged on both sides of the pipe and fixed on the triaxial measuring platform 32 by a bracket. Its optical path direction is perpendicular to the pipe axis and is used for non-contact measurement of the outer diameter of the pipe.

[0034] The triaxial measurement platform 32 includes precision slides in the X, Y, and Z directions. The laser measuring head 31 is driven to move by the electric adjustment mechanism 34 to adjust the distance between the measuring head and the surface of the pipe, ensuring that the laser spot is in the optimal focusing state.

[0035] The data processor 33 receives the trigger signal from the angle sensing switch 25 and controls the laser measuring head 31 to collect data in an equal angle interval mode. At the same time, it dynamically adjusts the sampling frequency according to the real-time rotation speed of the drive motor 23 to ensure that the measurement points are evenly distributed.

[0036] The electric adjustment mechanism 34 is electrically connected to the data processor 33. In the initial stage of measurement, it automatically adjusts the position of the triaxial measurement platform 32 according to the feedback signal of the laser measuring head 31, so that the laser measuring head 31 can quickly align with the surface of the pipe.

[0037] The method of using this utility model is as follows:

[0038] 1. Place the PVC pipe in the V-groove of the support wheel 13, and adjust the spacing of the support wheels 13 by adjusting the rollers 15 to align the pipe axis with the center of the rotary table 22;

[0039] 2. Start the drive motor 23 to drive the pipe to rotate at a constant speed. The horizontal position detection switch 24 monitors the position of the pipe in real time, and the angle sensing switch 25 sends the angle trigger signal synchronously.

[0040] 3. The laser measuring head 31 collects outer diameter data according to the trigger signal, and the data processor 33 filters the data and calculates the ellipticity.

[0041] 4. If the pipe offset exceeds the limit or the measurement is completed, the system will automatically stop and output a test report.

[0042] This utility model is a laser measuring device for the outer diameter of plastic pipes. It is designed for the measurement needs of PVC plastic pipes. Through structural innovation and intelligent control, it significantly improves the measurement accuracy and operation efficiency.

[0043] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A laser measuring device for the outer diameter of plastic pipes, characterized in that, include: Support assembly (1): includes a worktable (11), two parallel guide rails (12) set on the worktable (11), and at least one pair of adjustable spacing support wheels (13) slidably connected to the guide rails (12); the support wheels (13) are connected to the guide rails (12) through a position adjustment slide (14) and equipped with adjustment rollers (15) to adapt to pipes of different diameters; Rotary drive assembly (2): set at one end of the support assembly (1), including a fixed base (21), a turntable (22) installed on the side of the fixed base (21), a drive motor (23) for driving the turntable (22) to rotate, a horizontal position detection switch (24) for detecting the horizontal position of the pipe, and an angle sensing switch (25); the drive motor (23) is connected to the guide rails (12) through gears or belts. The transmission connection is a rotary table (22); the measurement component (3) includes two laser measuring heads (31) arranged opposite each other, a three-axis measuring platform (32) for fixing the laser measuring heads (31) and a data processor (33). The optical path of the laser measuring head (31) is perpendicular to the pipe axis, and its distance from the pipe surface is adjusted by the three-axis measuring platform (32). The rim of the support wheel (13) is V-shaped and covered with a rubber layer (133) to limit the axial displacement of the pipe and reduce surface scratches. The angle sensing switch (25) is a magnetic or photoelectric encoder. When the rotary table (22) rotates to the set angle, it triggers the laser measuring head (31) to collect data in an equal angle interval mode, and extracts a valid data point every 0.1°.

2. The laser measuring device for the outer diameter of plastic pipes according to claim 1, characterized in that, The laser measuring head (31) has a wavelength of 850-1550nm and a measurement frequency of 100-500Hz. The data processor (33) dynamically adjusts the sampling interval according to the real-time rotation speed of the rotary table (22) to ensure that at least 3 data points are collected for every 1° rotation.

3. The plastic pipe outside diameter laser measuring device of claim 1, wherein, The horizontal position detection switch (24) is a photoelectric sensor or a mechanical limit switch. When the pipe offset from the center of the rotary table (22) exceeds ±2mm, an audible and visual alarm is triggered and the drive motor (23) is paused.

4. The plastic pipe outside diameter laser measuring device of claim 1, wherein, The triaxial measurement platform (32) is equipped with an electric adjustment mechanism (34), which is connected to a data processor (33) and automatically adjusts the distance between the laser measuring head (31) and the surface of the pipe to the optimal focusing range according to the initial measurement value of the outer diameter of the pipe.

5. The plastic pipe outside diameter laser measuring device of claim 1, wherein, The drive motor (23) is a servo motor, and its rotation speed and the sampling frequency of the laser measuring head (31) are controlled in a closed loop by the data processor (33) to ensure that the measurement data is evenly distributed during the rotation of the pipe.

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