A Geometric Intelligent Detection Device and Method for Laser Cladding on the Inner Wall of a Cylindrical Cylinder

Abstract

A laser cladding geometric intelligent detection device and method for the inner wall of a cylindrical cylinder relate to the field of geometric detection in laser cladding processing, and particularly to the detection of the geometric shape and tolerance dimensions of the inner wall of a cylindrical cylinder. In particular, it relates to a laser cladding geometric intelligent detection device and method for the inner wall of a cylindrical cylinder, including a main body and a driving device fixedly arranged on the main body. The driving device is connected with a detection mechanism for detection through an adaptive umbrella support mechanism; the detection mechanism includes at least three groups of detection devices; the present invention measures the inner hole diameter by the three-point centering principle. The main body of the measuring device is placed outside the hole, and the detection mechanism enters the hole. The adaptive umbrella support mechanism is driven by the driving device to be centered with the inner surface of the workpiece to be measured, and then evaluation parameters such as the diameter and cylindricity of the surface to be measured are measured and analyzed by a distance sensor. The invention has the characteristics of intelligence, low cost and online detection can be realized.

Description

Technical Field

[0001] The present invention relates to the field of geometric detection in laser cladding processing, in particular to the detection of the geometric shape and tolerance dimensions of the inner wall of a cylindrical cylinder, and particularly to a laser cladding geometric intelligent detection device and method for the inner wall of a cylindrical cylinder. Background Technique

[0002] In recent years, with the rapid upgrading and development of China's remanufacturing industry, the laser cladding remanufacturing technology has been widely applied in several typical industrial fields and has obtained a relatively broad market scale. However, the detection of geometric parameters after laser cladding repair is not yet mature. In particular, it is almost impossible to directly measure the geometric parameters of the inner wall of the cylinder part after repair online. Therefore, we cannot obtain the geometric parameters of the inner wall of the repaired cylinder, that is, we cannot directly evaluate the performance after laser cladding remanufacturing, which also affects the implementation difficulty of subsequent processing.

[0003] Currently, common internal hole measuring instruments in the industrial field, such as manual micrometers, coordinate measuring machines, or cylindricity measuring instruments, etc., cannot realize the real-time online detection of the machined surface (with large roughness) of the inner wall of the cylinder after laser cladding. Currently, the industrial community lacks suitable methods for detecting the diameter and cylindricity of large and medium-sized apertures (100 - 1000 mm) and deeper inner wall holes. The representative research of existing approximate methods is as follows:

[0004] For example: In the literature "4-DOF Internal Detection Robot System for Large Aperture Pipelines [J]. Chinese Journal of Mechanical Engineering, 2009, 267:273", a detection system combining a walking mechanism, a slewing mechanism, a laser adjustment mechanism, etc. was constructed using multiple motors. This system realizes the detection of radial distance by calculating the laser travel time and can be applied to the detection operation of large apertures with a diameter of 500 - 1000 mm. Due to the limitations of the slewing mechanism itself, this device cannot be miniaturized to adapt to the on-line surface measurement of laser cladding parts, and strict centering adjustment is required during the detection of each cross-section, which reduces the detection efficiency. In addition, due to the absence of a pose detection system, the axes and cylindricity information of the hole part cannot be directly constructed by correlating multiple cross-sections.

[0005] In the literature "Research on 3D Comprehensive Measurement Technology for the Inner Surface of Deep Hole Parts [D]. University of Science and Technology of China, 2018", a CCD camera is combined with a ring laser generator, a ball screw, and a quartz tube. While the ball screw feeds, the CCD continuously takes pictures of the inner hole cross-section images, and then combines image processing technology to calculate the geometric quantity information of each cross-section. For small apertures below 100 mm, the radial theoretical accuracy is relatively good. However, since the camera takes pictures of the entire aperture image, the algorithm processing of this system for the laser cladding surface has great difficulty in resolution, that is, the accuracy is low, and it cannot be applied to deep holes with a length in the order of meters, which will lead to large errors and poor repeatability in the comprehensive detection results of cylindricity.

[0006] In the patent "A Deep Hole Cylindricity Detection Device and Method Adapted to Variable Apertures [P], Application No. 202110412570.1, Huazhong University of Science and Technology, 2021", a deep hole cylindricity detection device and method adapted to variable apertures are disclosed. The device realizes automatic walking along the inner wall by means of rollers of three pairs of self-centering devices, and realizes diameter measurement by means of a non-diffracting light generator and a pose measurement device. However, the diameter-changing method of this device uses the deformation of elastic elements, and the diameter-changing range is very small. Moreover, the laser reflection measurement method has high requirements for the inner surface and is not suitable for the surface after laser cladding. In addition, this device uses a three-stage transmission method to walk on the inner wall and is not suitable for on-line monitoring.

[0007] Based on this, the present invention develops an automatic centering and large-scale variable-diameter detection mechanism based on the umbrella support telescopic structure of the driving device, and uses the ultrasonic ranging method to solve the problem of rough measurement of the cladding surface. This device can be used in a handheld manner or an automatic manner, and can conveniently and quickly realize on-line detection of the diameter and cylindricity of the laser cladding surface on the inner wall of the cylinder. Summary of the Invention

[0008] The present invention proposes an umbrella claw type detection device mainly used for detecting the geometric parameters of the inner wall surface of a cylindrical cylinder. Through the detection of the inner wall contour after product repair and data analysis, and then through data processing, the measurement results are obtained, realizing the intelligent detection of the inner wall of the cylindrical cylinder. This invention has the characteristics of intelligence, low cost and on-line detection.

[0009] An intelligent detection device for laser cladding geometry of the inner wall of a cylindrical cylinder according to the present invention includes a main body and a driving device fixedly arranged on the main body. The driving device is connected with a detection mechanism for detection through an adaptive umbrella support mechanism;

[0010] The detection mechanism includes at least three groups of detection devices. Each detection device includes a mounting seat, and a spherical probe and a distance sensor are arranged on the mounting seat;

[0011] All the mounting seats are slidably connected with the same connecting device. The mounting seats are evenly distributed along the circumference of the connecting device and are at the same height. The distance sensor is arranged at one end of the mounting seat facing the connecting device, and the spherical probe is arranged at one end of the mounting seat far from the connecting seat;

[0012] The adaptive umbrella support mechanism includes a moving platform and an adaptive centering connecting device. The number of adaptive centering connecting devices includes connecting arms with the same number as the detection devices. The mounting seats are respectively connected with the moving platform through the connecting arms;

[0013] An output shaft is connected to the driving device, and the output shaft is connected with the moving platform through a lifting device;

[0014] When the moving platform moves, the mounting base is driven to move radially along the cylinder body through the adaptive centering connection device.

[0015] Preferably, the connecting device includes a balance table and connecting rods. The connecting rods are evenly distributed circumferentially along the balance table, and the number of connecting rods is the same as the number of mounting bases.

[0016] A slider is arranged on each mounting base. One end of the connecting rod is fixedly connected to the circumferential surface of the balance table, and the other end forms a moving pair with the slider in the mounting base.

[0017] Preferably, the connecting arm includes a connecting rod and a rocker. One end of the connecting rod passes through the top cover and is hinged to the moving platform, and the other end is hinged to the middle of the rocker. One end of the rocker is hinged to the top cover, and the other end is respectively hinged to the mounting base. The top cover is fixedly connected to the body.

[0018] Preferably, the top cover is provided with through holes with the same number as the connecting rods, and the positions of the through holes correspond to the positions where the connecting rods are hinged to the moving platform.

[0019] When the spherical probe contacts the inner wall of the cylinder body, the displacement of the connecting rod in the through hole is less than the maximum displacement of the connecting rod in the through hole.

[0020] Preferably, the through holes match the movement trajectories of the connecting rods.

[0021] Preferably, the lifting device includes a vertically arranged lead screw and a lead screw nut sleeved on the lead screw and connected to the lead screw. A through hole is arranged at the central part of the moving platform, and the diameter of the through hole is larger than the outer diameter of the lead screw. The moving platform is sleeved on the lead screw and fixedly connected to the lead screw nut.

[0022] One end of the lead screw is connected to the driving device through a flexible coupling, and the other end passes through the through hole of the moving platform and is axially fixedly connected to the center of the top cover through a deep groove ball bearing.

[0023] The driving device is fixedly connected to the body through an intermediate fixing plate.

[0024] The detection device is arranged in three groups.

[0025] Preferably, the driving device is a driving motor.

[0026] Preferably, the body is a hollow cylindrical body. The bottom of the body is fixedly connected with a bottom plate. The top cover covers the top of the body. The driving motor, the lead screw and the intermediate fixing plate are all located inside the body.

[0027] Preferably, the distance sensor is an ultrasonic ranging sensor.

[0028] A geometric intelligent detection method for the inner wall of a cylindrical cylinder by laser cladding, which is detected by a geometric intelligent detection device for the inner wall of a cylindrical cylinder. The specific method includes the following steps:

[0029] Step 1: Place a geometric intelligent detection device for the inner wall of a cylindrical cylinder into the cylinder to be measured;

[0030] Step 2: Start the driving device. The output shaft of the driving device drives the lead screw to rotate, thereby driving the lead screw nut to move downward;

[0031] Step 3: The movement of the lead screw nut drives the moving platform of the adaptive umbrella support mechanism to move downward, so that the three groups of connecting rods pull the three groups of rockers to swing outward;

[0032] Step 4: The swing of the rocker drives the mounting seats of the detection mechanism to slide away from the balance platform on the connecting rods respectively;

[0033] Step 5: When the spherical probe on one of the detection mechanisms contacts the inner surface of the cylinder to be measured, automatically drive the adaptive umbrella support mechanism to align with the cylinder to be measured;

[0034] Step 6: When the three spherical probes of the detection mechanism all contact the inner surface of the cylinder to be measured, a pre-pressure is generated. The driving force is transmitted to the driving device through the connecting arm and the lifting device. When the pre-pressure is greater than the set torque of the driving device in the torque driving mode, the driving device stops rotating;

[0035] Step 7: The three groups of distance sensors measure three groups of diameter values, and calculate the diameter D and the cylindricity variance D' of the inner wall of the cylinder to be measured, that is:

[0036] D = (D1 + D2 + D3) / 3

[0037] D' = [(D1 - D) 2 + (D2 - D) 2 + (D2 - D) 2 1 / 2

[0038] Where: D1, D2, D3 are the test values of the three groups of distance sensors;

[0039] Step 8: The driving device rotates in the reverse direction, drives the lead screw nut to rotate to the uppermost end of the lead screw and then stops. After the adaptive umbrella support mechanism contracts, one measurement is completed.

[0040] ​The present invention adopts a measuring device for measuring the inner diameter by a three-point centering principle. The body of the measuring device is placed outside the hole, and the detection mechanism enters the hole. The adaptive umbrella support mechanism is driven by a driving device to be centered with the inner surface of the workpiece to be measured, and then the evaluation parameters such as the diameter and cylindricity of the surface to be measured are measured and analyzed by a distance sensor. The invention has the characteristics of intelligence, low cost and online detection, and has a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 is a schematic diagram of the overall structure of the present invention.

[0042] Figure 2 is a schematic diagram of the structure of the driving device of the present invention.

[0043] Figure 3 is a schematic diagram of the structure of the adaptive umbrella support mechanism of the present invention.

[0044] Figure 4 is a schematic diagram of the structure of the detection mechanism of the present invention.

[0045] Reference numerals: 1 - driving device, 1-1 - bottom plate, 1-2 - driving motor, 1-3 - body, 1-4 - intermediate fixing plate, 1-5 - flexible coupling, 1-6 - lead screw nut, 1-7 - lead screw, 1-8 - top cover, 1-9 - deep groove ball bearing, 1-10 - control and display unit, 2 - adaptive umbrella support mechanism, 2-1 - moving platform, 2-2 - connecting rod, 2-3 - rocker, 3 - detection mechanism, 3-1 - mounting seat, 3-2 - spherical probe, 3-3 - ultrasonic distance sensor, 3-4 - balance table. DETAILED DESCRIPTION OF THE INVENTION

[0046] A laser cladding geometric intelligent detection device for the inner wall of a cylindrical cylinder of the present invention includes a body 1-3 and a driving device 1 fixedly arranged on the body 1-3. The driving device 1 is connected with a detection mechanism 3 for detection through an adaptive umbrella support mechanism 2;

[0047] The detection mechanism 3 includes at least three groups of detection devices. Each detection device includes a mounting seat 3-1, and a spherical probe 3-2 and a distance sensor are arranged on the mounting seat 3-1;

[0048] The mounting seats 3-1 are all slidably connected to the same connecting device. The mounting seats 3-1 are circumferentially evenly distributed and are at the same height. The distance sensor is arranged at one end of the mounting seat 3-1 facing the connecting device, and the spherical probe 3-2 is arranged at one end of the mounting seat 3-1 away from the connecting seat;

[0049] The adaptive umbrella support mechanism 2 includes a moving platform 2-1 and an adaptive centering connection device. The number of the adaptive centering connection devices includes connection arms equal in number to the number of detection devices. The mounting seats 3-1 are respectively connected to the moving platform 2-1 through the connection arms;

[0050] An output shaft is connected to the driving device 1, and the output shaft is connected to the moving platform 2-1 through a lifting device;

[0051] When the moving platform 2-1 moves, the mounting seats 3-1 are driven to move radially along the cylinder body through the adaptive centering connection device.

[0052] The connection device includes a balance table 3-4 and connecting rods. The connecting rods are evenly distributed along the circumferential direction of the balance table 3-4, and the number of the connecting rods is the same as the number of the mounting seats 3-1;

[0053] A slider is arranged on each of the mounting seats 3-1. One end of the connecting rod is fixedly connected to the circumferential surface of the balance table 3-4, and the other end forms a moving pair with the slider in the mounting seat 3-1.

[0054] The connection arm includes a connecting rod 2-2 and a rocker 2-3. One end of the connecting rod 2-2 passes through the top cover 1-8 and is hinged to the moving platform 2-1, and the other end is hinged to the middle of the rocker 2-3. One end of the rocker 2-3 is hinged to the top cover 1-8, and the other end is respectively hinged to the mounting seats 3-1. The top cover 1-8 is fixedly connected to the body 1-3.

[0055] The top cover 1-8 is provided with through holes equal in number to the number of the connecting rods 2-2, and the positions where the through holes are arranged correspond to the positions where the connecting rods 2-2 are hinged to the moving platform 2-1;

[0056] When the spherical probe 3-2 contacts the inner wall of the cylinder body, the displacement of the connecting rod 2-2 in the through hole is less than the maximum displacement of the connecting rod 2-2 in the through hole.

[0057] The through holes match the movement trajectories of the connecting rods 2-2.

[0058] The lifting device includes a vertically arranged lead screw 1-7 and a lead screw nut 1-6 sleeved on the lead screw 1-7 and connected to the lead screw 1-7. A through hole is arranged at the central part of the moving platform 2-1, and the diameter of the through hole is larger than the outer diameter of the lead screw 1-7. The moving platform 2-1 is sleeved on the lead screw 1-7 and is fixedly connected to the lead screw nut 1-6;

[0059] One end of the lead screw 1-7 is connected to the driving device 1 through a flexible coupling 1-5, and the other end passes through the through hole of the moving platform 2-1 and is axially fixedly connected to the center of the top cover 1-8 through a deep groove ball bearing 1-9;

[0060] The driving device 1 is fixedly connected to the body 1-3 through an intermediate fixing plate 1-4;

[0061] The detection devices are set in three groups.

[0062] The driving device 1 is a driving motor 1-2.

[0063] The main body 1-3 is a hollow cylindrical main body 1-3. The bottom of the main body 1-3 is fixedly connected with a bottom plate 1-1. The top cover 1-8 covers the top of the main body 1-3. The driving motor 1-2, the lead screw 1-7 and the intermediate fixing plate 1-4 are all located inside the main body 1-3.

[0064] The distance sensor is an ultrasonic ranging sensor 3-3.

[0065] The distance sensor is an ultrasonic ranging sensor 3-3. A control and display unit 1-10 can be arranged on the circumferential surface of the main body 1-3 as required. The control and display unit 1-10 is connected to the distance sensor of the detection device and is used to display the corresponding measurement data.

[0066] A method for geometric intelligent detection of laser cladding on the inner wall of a cylindrical cylinder uses a geometric intelligent detection device for laser cladding on the inner wall of a cylindrical cylinder for detection. The specific method includes the following steps:

[0067] Step 1: Place a geometric intelligent detection device for laser cladding on the inner wall of a cylindrical cylinder into the cylinder to be measured.

[0068] Step 2: Start the driving device 1. The output shaft of the driving device 1 drives the lead screw 1-7 to rotate, thereby driving the lead screw nut 1-6 to move downward.

[0069] Step 3: The movement of the lead screw nut 1-6 drives the moving platform 2-1 of the adaptive umbrella support mechanism 2 to move downward, so that the three connecting rods 2-2 pull the three rockers 2-3 to swing outward.

[0070] Step 4: The swinging of the rocker 2-3 drives the mounting seats 3-1 of the detection mechanisms 3 to slide away from the balance platform 3-4 on the connecting rods respectively.

[0071] Step 5: When the spherical probe 3-2 on one of the detection mechanisms 3 contacts the inner surface of the cylinder to be measured, automatically drive the adaptive umbrella support mechanism 2 to be centered with the cylinder to be measured.

[0072] Step 6: When the three spherical probes 3-2 of the detection mechanism 3 all contact the inner surface of the cylinder to be measured, a pre-pressure is generated. The driving force is transmitted to the driving device 1 through the connecting arm and the lifting device. When the pre-pressure is greater than the set torque of the driving device 1 in the torque driving mode, the driving device 1 stops rotating.

[0073] Step 7: The three groups of distance sensors measure three groups of diameter values, and calculate the diameter D and cylindricity variance D' of the inner wall of the cylinder to be measured, that is:

[0074] D = (D1 + D2 + D3) / 3

[0075] D' = [(D1 - D) 2 + (D2 - D) 2 + (D2 - D) 2 1 / 2

[0076] Where: D1, D2, and D3 are the measured values of the three groups of distance sensors;

[0077] Step 8: The driving device 1 rotates reversely, drives the lead screw nut 1-6 to rotate to the uppermost end of the lead screw 1-7 and then stops. After the adaptive umbrella support mechanism 2 contracts, one measurement is completed.​

Claims

1. A geometric intelligent detection method for the inner wall of a cylindrical cylinder, characterized in that, Detection is carried out using a geometric intelligent detection device for laser cladding on the inner wall of a cylindrical cylinder. The specific method includes the following steps: Step 1: Place a geometric intelligent detection device for laser cladding on the inner wall of a cylindrical cylinder into the cylinder to be measured. Step 2: Start the driving device (1). The output shaft of the driving device (1) drives the lead screw (1-7) to rotate, thereby driving the lead screw nut (1-6) to move downward. Step 3: The movement of the lead screw nut (1-6) drives the moving platform (2-1) of the adaptive umbrella support mechanism (2) to move downward, so that the three connecting rods (2-2) pull the three rockers (2-3) to swing outward. Step 4: The swing of the rocker (2-3) drives the mounting seats (3-1) of the detection mechanism (3) to slide away from the balance platform (3-4) on the connecting rods respectively. Step 5: When the spherical probe (3-2) on one of the detection mechanisms (3) contacts the inner surface of the cylinder to be measured, automatically drive the adaptive umbrella support mechanism (2) to be centered with the cylinder to be measured. Step 6: When the three spherical probes (3-2) of the detection mechanism (3) all contact the inner surface of the cylinder to be measured, pre-pressure is generated. The driving force is transmitted to the driving device (1) through the connecting arm and the lifting device. When the pre-pressure is greater than the set torque of the driving device (1) in the torque driving mode, the driving device (1) stops rotating. Step 7: The three distance sensors measure three diameter values, and calculate the diameter D and the cylindricity variance D' of the inner wall of the cylinder to be measured, that is: D = (D1 + D2 + D3) / 3 D’ = [(D1 - D) 2 + (D2 - D) 2 + (D2 - D) 2 1 / 2 ​ Where: D1, D2, and D3 are the test values of the three distance sensors. Step 8: The driving device (1) rotates in the reverse direction, drives the lead screw nut (1-6) to rotate to the uppermost end of the lead screw (1-7) and then stops. After the adaptive umbrella support mechanism (2) contracts, one measurement is completed. The geometric intelligent detection device for laser cladding on the inner wall of a cylindrical cylinder includes a main body (1-3) and a driving device (1) fixedly arranged on the main body (1-3). The driving device (1) is connected with a detection mechanism (3) for detection through an adaptive umbrella support mechanism (2). The detection mechanism (3) includes at least three detection devices. Each detection device includes a mounting seat (3-1), and a spherical probe (3-2) and a distance sensor are arranged on the mounting seat (3-1). The mounting seats (3-1) are all slidably connected to the same connecting device. The mounting seats (3-1) are evenly distributed along the circumference of the connecting device and are at the same height. The distance sensor is arranged at one end of the mounting seat (3-1) facing the connecting device, and the spherical probe (3-2) is arranged at the end of the mounting seat (3-1) away from the connecting seat. The adaptive umbrella support mechanism (2) includes a moving platform (2-1) and an adaptive centering connecting device. The adaptive centering connecting device includes connecting arms with the same number as the number of detection devices. The mounting seats (3-1) are respectively connected to the moving platform (2-1) through the connecting arms. An output shaft is connected to the driving device (1), and the output shaft is connected to the moving platform (2-1) through a lifting device. When the moving platform (2-1) moves, it drives the mounting base (3-1) to move radially along the cylinder body through the adaptive centering connection device; The connecting arm includes a connecting rod (2-2) and a rocker (2-3). One end of the connecting rod (2-2) passes through the top cover (1-8) and is hinged to the moving platform (2-1), and the other end is hinged to the middle of the rocker (2-3). One end of the rocker (2-3) is hinged to the top cover (1-8), and the other end is respectively hinged to the mounting base (3-1). The top cover (1-8) is fixedly connected to the main body (1-3); The lifting device includes a vertically arranged lead screw (1-7) and a lead screw nut (1-6) sleeved on the lead screw (1-7) and connected to the lead screw (1-7). A through hole is provided in the central part of the moving platform (2-1), and the diameter of the through hole is larger than the outer diameter of the lead screw (1-7). The moving platform (2-1) is sleeved on the lead screw (1-7) and is fixedly connected to the lead screw nut (1-6); One end of the lead screw (1-7) is connected to the driving device (1) through a flexible coupling (1-5), and the other end passes through the through hole of the moving platform (2-1) and is axially fixedly connected to the center of the top cover (1-8) through a deep groove ball bearing (1-9); The driving device (1) is fixedly connected to the main body (1-3) through an intermediate fixing plate (1-4); The detection device is set in three groups.

2. The geometric intelligent detection method for the inner wall of a cylindrical cylinder according to claim 1, characterized in that, The connecting device includes a balance table (3-4) and connecting rods. The connecting rods are evenly distributed along the circumference of the balance table (3-4), and the number of connecting rods is the same as the number of mounting bases (3-1); A slider is provided on each of the mounting bases (3-1). One end of the connecting rod is fixedly connected to the circumferential surface of the balance table (3-4), and the other end forms a moving pair with the slider in the mounting base (3-1).

3. The geometric intelligent detection method for the inner wall of a cylindrical cylinder according to claim 2, characterized in that, The top cover (1-8) is provided with through holes having the same number as the connecting rods (2-2), and the positions of the through holes are corresponding to the positions where the connecting rods (2-2) are hinged to the moving platform (2-1); When the spherical probe (3-2) contacts the inner wall of the cylinder body, the displacement of the connecting rod (2-2) in the through hole is less than the maximum displacement of the connecting rod (2-2) in the through hole.

4. The geometric intelligent detection method for the inner wall of a cylindrical cylinder according to claim 3, characterized in that, The through hole matches the movement trajectory of the connecting rod (2-2).

5. The geometric intelligent detection method for the inner wall of a cylindrical cylinder according to claim 4, characterized in that, The driving device (1) is a driving motor (1-2).

6. The geometric intelligent detection method for the inner wall of a cylindrical cylinder according to claim 5, characterized in that, The main body (1-3) is a hollow cylindrical main body (1-3). The bottom of the main body (1-3) is fixedly connected with a bottom plate (1-1). The top cover (1-8) covers the top of the main body (1-3). The driving motor (1-2), the lead screw (1-7) and the intermediate fixing plate (1-4) are all located inside the main body (1-3).

7. The geometric intelligent detection method for laser cladding on the inner wall of a cylindrical cylinder according to claim 6, characterized in that, The distance sensor is an ultrasonic ranging sensor (3-3).

Images