Thread defect detection device and detection method suitable for multi-diameter bolt holes

Abstract

The invention relates to the technical field of bolt hole defect detection, and provides a thread defect detection device and method suitable for multi-diameter bolt holes, the detection device comprises an image acquisition device, and further comprises a mounting seat, the image acquisition device is mounted on the mounting seat, and the mounting seat is connected with a walking mechanism through a connector; and the pitching angle adjusting assembly is connected between the connector and the mounting seat and is used for adjusting the pitching angle of the image acquisition equipment so as to respectively perform image acquisition on the thread upper surface and the thread lower surface. According to the invention, image acquisition can be respectively carried out on the thread upper surface and the thread lower surface of the bolt hole, complete data of the two surfaces can be conveniently acquired, and the thread defect detection precision is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of bolt hole defect detection, and in particular to a thread defect detection device and a detection method suitable for multi-diameter bolt holes. Background Art

[0002] At present, bolt hole defect detection is a key link in the maintenance and inspection of large mechanical equipment such as reactor pressure vessels. Especially under the high temperature and high pressure conditions of nuclear power plants, the threaded surface of the main bolt hole is prone to fatigue damage or defects, which directly affects the sealing performance of the pressure vessel and the overall safety of the equipment.

[0003] In the existing technology, the thread defect detection device is installed on a traveling mechanism, which can drive the detection device to rise and fall, and at the same time drive the thread defect detection device to perform circular motion around the axis of the bolt hole. During detection, the bolt hole faces upward, the thread defect detection device rotates and descends, and uses a carried wireless camera, industrial camera or laser scanner and other image acquisition equipment to capture images of the thread surface, thereby detecting thread defects.

[0004] The surfaces of the two tooth sides where the top of the thread connects to the adjacent tooth bottom are oriented in different directions. When the bolt hole is facing upward, one tooth side surface is facing downward (hereinafter defined as the upper surface of the thread), and the other tooth side surface is facing upward (hereinafter defined as the lower surface of the thread). However, in the existing technology, images of the upper and lower surfaces of the thread are captured simultaneously, making it difficult to capture complete data of the two tooth side surfaces, and the detection accuracy is low. Summary of the Invention

[0005] The object of the present invention is to provide a thread defect detection device and detection method suitable for multi-diameter bolt holes, so as to solve the above-mentioned defects of the prior art.

[0006] The present invention is achieved through the following technical solutions:

[0007] A thread defect detection device suitable for multi-diameter bolt holes includes an image acquisition device and further includes:

[0008] A mounting base, on which the image acquisition device is mounted, and the mounting base is connected to the walking mechanism via a connector; and

[0009] The pitch angle adjustment component is connected between the connector and the mounting base, and is used to adjust the pitch angle of the image acquisition device to respectively capture images of the upper and lower surfaces of the threads.

[0010] Optionally, the detection device also includes a tilt angle adjustment component for adjusting the tilt angle of the image acquisition device; when the pitch angle of the image acquisition device is adjusted, the image acquisition device rotates around a first axis perpendicular to the axis of the bolt hole, and when the tilt angle of the image acquisition device is adjusted, the image acquisition device rotates around a second axis, and the second axis is perpendicular to the first axis and the axis of the bolt hole, respectively.

[0011] Optionally, the detection device further includes a sliding adjustment component for adjusting the distance between the image acquisition device and the axis of the bolt hole.

[0012] Optionally, the sliding adjustment component is a linear module, the sliding part of the linear module is connected to the pitch angle adjustment component, and the fixed part of the linear module is connected to the connector.

[0013] Optionally, the pitch angle adjustment assembly includes a pitch fixing seat, a pitch adjustment plate and a pitch driving element, the pitch fixing seat is connected to the connector, the mounting seat is connected to the pitch adjustment plate, one end of the pitch adjustment plate is rotatably connected to the pitch fixing seat, and the pitch driving element is used to drive the pitch adjustment plate to rotate;

[0014] The tilt angle adjustment assembly includes a tilt fixing seat, a tilt adjustment plate and a tilt driving element. The tilt fixing seat is fixedly connected to the pitch fixing seat, the connecting head is fixedly connected to the tilt adjustment plate, one end of the tilt adjustment plate is rotatably connected to the tilt fixing seat, and the tilt driving element is used to drive the tilt adjustment plate to rotate.

[0015] Optionally, a pitch fixed rotating shaft is passed through one end of the pitch adjustment plate, both ends of the pitch fixed rotating shaft are passed through the pitch fixing seat and one end is provided with a pitch fixed rotating gear, a pitch movable rotating shaft is passed through the middle portion of the pitch adjustment plate, pitch guide arc grooves are provided on both sides of the pitch fixing seat, both ends of the pitch movable rotating shaft are passed through the pitch guide arc grooves, and one end of the pitch movable rotating shaft is provided with a pitch movable gear meshing with the pitch fixed rotating gear;

[0016] One end of the tilt adjustment plate is provided with a tilt fixed rotating shaft, both ends of the tilt fixed rotating shaft are provided on the tilt fixed seat and one end is provided with a tilt fixed rotation gear, the middle part of the tilt adjustment plate is provided with a tilt movable rotating shaft, both sides of the tilt fixed seat are provided with tilt guide arc grooves, both ends of the tilt movable rotating shaft are provided in the tilt guide arc grooves, and one end of the tilt movable rotating shaft is provided with a tilt movable gear engaged with the tilt fixed rotation gear.

[0017] Optionally, a locking wheel is provided on one end of the pitch movable shaft away from the pitch movable gear and an end of the tilt movable shaft away from the tilt movable gear, and a locking component capable of limiting the rotation of the locking wheel is provided on the outer side of the locking wheel.

[0018] Optionally, the locking component includes an electromagnet, the locking wheel is a permanent magnet, and the locking wheel is circumferentially fixed and axially displaceably sleeved on the pitch movable shaft or the tilt movable shaft.

[0019] Optionally, a distance detection element is provided on the mounting base for detecting the distance between the image acquisition device and the threaded surface of the bolt hole.

[0020] The present invention also provides a method for detecting thread defects in bolt holes, using any one of the thread defect detection devices suitable for multi-diameter bolt holes described above. During the process of the detection device rotating and descending under the action of a walking mechanism, the pitch angle of the image acquisition device is adjusted so that it collects data on one of the upper and lower surfaces of the thread of the bolt hole; during the process of the detection device rotating and ascending under the action of the walking mechanism, the pitch angle of the image acquisition device is adjusted so that it collects data on the other of the upper and lower surfaces of the thread of the bolt hole.

[0021] The technical solution of the present invention has at least the following advantages and beneficial effects:

[0022] 1. In the present invention, the pitch angle adjustment component is capable of adjusting the pitch angle of the image acquisition device, and can respectively capture images of the upper and lower threaded surfaces of the bolt hole, thereby facilitating the collection of complete data of the two surfaces and improving the accuracy of thread defect detection.

[0023] 2. In the present invention, the tilt angle adjustment component is capable of adjusting the tilt angle of the image acquisition device. Moreover, since the tilt angle is rotated around the second axis during adjustment and the pitch angle is rotated around the first axis during adjustment, and the first axis and the second axis are perpendicular to each other, the tilt angle adjustment and the pitch angle adjustment enable the image acquisition device to rotate in two mutually perpendicular planes, with multiple degrees of rotational freedom, which is convenient for adapting to different detection needs.

[0024] 3. In the present invention, the sliding adjustment component is capable of driving the image acquisition device to move, thereby adjusting the distance between the image acquisition device and the axis of the bolt hole, so as to adapt to bolt holes of different diameters.

[0025] 4. In the present invention, a locking wheel is provided at one end of the pitch movable shaft away from the pitch movable gear and at one end of the tilt movable shaft away from the tilt movable gear. A locking component capable of limiting the rotation of the locking wheel is provided on the outer side of the locking wheel. This arrangement facilitates locking the locking wheel after the image acquisition device is adjusted into place to limit its rotation, thereby preventing the pitch movable gear and the tilt movable gear from moving in the gap space due to the existence of the gear gap, thereby avoiding slight shaking of the image acquisition device and affecting the image acquisition quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1A schematic structural diagram of a thread defect detection device suitable for multi-diameter bolt holes provided by the present invention;

[0027] Figure 2 This is the main view of the pitch angle adjustment component;

[0028] Figure 3 Schematic diagram of the pitch angle adjustment component Figure 1 ;

[0029] Figure 4 Schematic diagram of the pitch angle adjustment component Figure 2 ;

[0030] Figure 5 This is a front view of the tilt angle adjustment assembly;

[0031] Figure 6 Schematic diagram of the structure of the tilt angle adjustment component Figure 1 ;

[0032] Figure 7 Schematic diagram of the structure of the tilt angle adjustment component Figure 2 ;

[0033] Figure markings: 1-connector, 2-mounting seat, 3-image acquisition device, 4-pitch angle adjustment assembly, 401-pitch fixing seat, 402-pitch adjustment plate, 403-pitch driving element, 404-pitch fixed gear, 405-pitch movable gear, 5-tilt angle adjustment assembly, 501-tilt fixing seat, 502-tilt adjustment plate, 503-tilt driving element, 504-tilt fixed gear, 505-tilt movable gear, 6-sliding adjustment assembly, 7-locking wheel, 8-electromagnet, 9-distance detection element, 10-two-axis angle sensor. DETAILED DESCRIPTION

[0034] Example 1

[0035] refer to Figure 1 A thread defect detection device suitable for multi-diameter bolt holes includes an image acquisition device 3, a mounting base 2, and a pitch angle adjustment assembly 4. Optionally, in this embodiment, image acquisition device 3 is a three-dimensional laser profile scanner. Image acquisition device 3 is mounted on mounting base 2, which is connected to a travel mechanism (not shown) via a connector 1. The pitch angle adjustment assembly 4 is connected between connector 1 and mounting base 2. It can capture images of both the upper and lower threaded surfaces of the bolt hole, facilitating the collection of complete data from both surfaces and improving the accuracy of thread defect detection.

[0036] Based on the above, the detection device in this embodiment further includes a tilt angle adjustment assembly 5 and a slide adjustment assembly 6. The tilt angle adjustment assembly 5 is used to adjust the tilt angle of the image acquisition device 3. When adjusting the pitch angle, the image acquisition device 3 rotates about a first axis perpendicular to the axis of the bolt hole. When adjusting the tilt angle, the image acquisition device 3 rotates about a second axis, which is perpendicular to the first axis and the axis of the bolt hole, respectively. Therefore, tilt and pitch angle adjustment enable the image acquisition device 3 to rotate within two mutually perpendicular planes, providing multiple degrees of rotational freedom and facilitating adaptation to different detection requirements. The slide adjustment assembly 6 can drive the displacement of the image acquisition device 3, thereby adjusting the distance between the image acquisition device 3 and the axis of the bolt hole, facilitating adaptation to bolt holes of varying diameters.

[0037] refer to Figure 2-Figure 7 In this embodiment, the pitch angle adjustment assembly 4 includes a pitch fixing seat 401, a pitch adjustment plate 402, and a pitch driving element 403. The mounting seat 2 is connected to the pitch adjustment plate 402, one end of the pitch adjustment plate 402 is rotatably connected to the pitch fixing seat 401, and the pitch driving element 403 is used to drive the pitch adjustment plate 402 to rotate. The tilt angle adjustment assembly 5 includes a tilt fixing seat 501, a tilt adjustment plate 502, and a tilt driving element 503. The tilt fixing seat 501 is fixedly connected to the pitch fixing seat 401, the connector 1 is fixedly connected to the tilt adjustment plate 502, one end of the tilt adjustment plate 502 is rotatably connected to the tilt fixing seat 501, and the tilt driving element 503 is used to drive the tilt adjustment plate 502 to rotate. As an option, in this embodiment, the pitch driving element 403 and the tilt driving element 503 are both motors.

[0038] As an option, in this embodiment, the pitch actuator 403 drives the pitch adjustment plate 402 to rotate, and the tilt actuator 503 drives the tilt adjustment plate 502 to rotate as follows: The pitch fixing base 401 has a U-shaped structure, and the pitch adjustment plate 402 is disposed within the pitch fixing base 401. A pitch fixing shaft extends through one end of the pitch adjustment plate 402 (the pitch fixing shaft can rotate relative to the pitch adjustment plate 402), and both ends of the pitch fixing shaft extend through the pitch fixing base 401 (the pitch fixing shaft can rotate relative to the pitch fixing base 401). A pitch fixed rotating gear 404 is provided at one end of the pitch fixed shaft (the pitch fixed shaft and the pitch fixed rotating gear 404 are relatively fixed), a pitch movable rotating shaft is passed through the middle of the pitch adjustment plate 402 (the pitch movable rotating shaft can rotate relative to the pitch adjustment plate 402), and pitch guide arc grooves are provided on both sides of the pitch fixed seat 401 (it should be understood that the pitch guide arc groove is an arc groove with the pitch fixed rotating shaft as the center and the distance between the pitch movable rotating shaft and the pitch fixed rotating shaft as the radius), both ends of the pitch movable rotating shaft are passed through the pitch guide arc groove, and one end of the pitch movable rotating shaft is provided with a pitch fixed rotating shaft. The rotating gear 404 is engaged with the pitch movable gear 405 (the pitch movable gear 405 is relatively fixed to the pitch movable rotating shaft), and the output shaft of the pitch driving element 403 is connected to the pitch fixed rotating gear 404. When the pitch fixed rotating gear 404 rotates, the pitch movable gear 405 is driven. The pitch movable gear 405 can not only rotate on itself, but also revolve around the pitch fixed rotating gear 404, thereby driving the pitch movable rotating shaft to slide in the pitch guide arc groove, thereby realizing the pitch angle adjustment of the pitch adjustment plate 402, that is, realizing the pitch angle adjustment of the image acquisition device 3.

[0039] Similarly, the tilt fixing seat 501 has a U-shaped structure, and the tilt adjustment plate 502 is arranged in the tilt fixing seat 501. One end of the tilt adjustment plate 502 is provided with a tilt fixed shaft (the tilt fixed shaft can rotate relative to the tilt adjustment plate 502), and both ends of the tilt fixed shaft are provided on the tilt fixing seat 501 (the tilt fixed shaft can rotate relative to the tilt fixing seat 501). One end of the tilt fixed shaft is provided with a tilt fixed gear 504 (the tilt fixed shaft and the tilt fixed gear 504 are relatively fixed), the middle of the tilt adjustment plate 502 is provided with a tilt movable shaft (the tilt movable shaft can rotate relative to the tilt adjustment plate 502), and both sides of the tilt fixing seat 501 are provided with tilt guide arc grooves (it should be understood that the tilt guide arc groove is an arc-shaped groove with the tilt fixed shaft as the center and the distance between the tilt movable shaft and the tilt fixed shaft as the radius), the two ends of the tilt movable shaft are provided in the tilt guide arc groove, and one end of the tilt movable shaft is provided with a gear that is connected to the tilt fixed gear 504 The meshed tilt movable gear 505 (the tilt movable gear 505 is relatively fixed to the tilt movable rotating shaft), the output shaft of the tilt driving element 503 is connected to the tilt fixed rotating gear 504, which drives the tilt movable gear 505 when the tilt fixed rotating gear 504 rotates. The tilt movable gear 505 can not only rotate on itself, but also revolve around the tilt fixed rotating gear 504, thereby driving the tilt movable rotating shaft to slide in the tilt guide arc groove. Since the tilt adjustment plate 502 is relatively fixed to the connector 1, it is equivalent to the rotation of the tilt adjustment seat, thereby realizing the tilt angle adjustment of the image acquisition device 3.

[0040] It should be understood that in other embodiments, the pitch drive element 403 drives the pitch adjustment plate 402 to rotate, and the tilt drive element 503 drives the tilt adjustment plate 502 to rotate. Of course, other methods can also be used, such as directly driving the pitch adjustment plate 402 and the tilt adjustment plate 502 to rotate through components such as servos.

[0041] On this basis, a locking wheel 7 is provided at the end of the pitch movable shaft remote from the pitch movable gear 405 and at the end of the tilt movable shaft remote from the tilt movable gear 505. A locking component is provided on the outer side of the locking wheel 7 to restrict its rotation. It is worth noting that pitch angle adjustment (tilt angle adjustment) is achieved by rotating the pitch fixed gear 404 (tilt fixed gear 504), which in turn drives the pitch movable gear 405 (tilt movable gear 505). Due to the gap in the gear transmission, the image acquisition device 3 may wobble slightly within the gap, thereby affecting image acquisition quality and detection accuracy. The presence of the locking component can lock the locking wheel 7, restricting the rotation of the pitch movable shaft and the tilt movable shaft, effectively resolving the above-mentioned problem.

[0042] As an option, in this embodiment, the locking component includes an electromagnet 8, and the locking wheel 7 is a permanent magnet. The locking wheel 7 is circumferentially fixed and axially movable on the pitch movable shaft or the tilt movable shaft. Specifically, the end of the pitch movable shaft or the tilt movable shaft on which the locking wheel 7 is sleeved has a rectangular structure, and the center of the locking wheel 7 is provided with a rectangular hole that cooperates with it, so that the locking wheel 7 can move axially but cannot rotate circumferentially. After the angle is adjusted to the right position, the electromagnet 8 becomes magnetic, attracting the locking wheel 7, thereby locking the locking wheel 7. In other embodiments, the locking component can of course adopt other structures. For example, the locking component may include a friction plate and an electric push rod, and the electric push rod drives the friction plate to press against the locking wheel 7, thereby utilizing friction to achieve locking of the locking wheel 7.

[0043] refer to Figure 1 In this embodiment, a two-axis angle sensor 10 is provided on the mounting base 2. This two-axis angle sensor 10, also commonly referred to as a dual-axis tilt sensor, is an important posture sensor used to measure the tilt angle of an object along two different axes. Its application in the present invention facilitates detection of the pitch and tilt angles of the image acquisition device 3.

[0044] refer to Figure 1 and Figure 2 Alternatively, in this embodiment, the sliding adjustment assembly 6 is a linear module. Specifically, based on the above, the sliding portion of the linear module is connected to the tilt adjustment plate 502, and the fixed portion of the linear module is connected to the connector 1. During operation, the linear module drives the overall displacement of the tilt angle adjustment assembly 5, the pitch angle adjustment assembly 4, and the image acquisition device 3. In other embodiments, the sliding adjustment assembly 6 can also be implemented using other structures, such as using the movement of an electric linear actuator to achieve displacement adjustment.

[0045] Reference again Figure 1 In this embodiment, a distance detection element 9 is provided on the mounting base 2 for detecting the distance between the image acquisition device 3 and the threaded surface of the bolt hole, thereby guiding the operation of the sliding adjustment assembly 6 based on the detection result. Alternatively, a laser rangefinder can be used as the distance detection element 9. In other embodiments, other options for the distance detection element 9 are also possible, such as a displacement sensor.

[0046] Example 2

[0047] This embodiment provides a method for detecting thread defects in bolt holes. The method utilizes the thread defect detection device for multi-diameter bolt holes provided in Example 1. As the detection device rotates and descends under the action of a traveling mechanism, the pitch angle of an image acquisition device 3 is adjusted to capture data from either the upper or lower thread surface of the bolt hole. As the detection device rotates and ascends under the action of the traveling mechanism, the pitch angle of the image acquisition device 3 is adjusted to capture data from the other of the two. This method captures images of both the upper and lower thread surfaces of the bolt hole separately, facilitating the collection of complete data from both surfaces and improving the accuracy of thread defect detection.

[0048] For example, the image acquisition device 3 is first tilted upward, and during the process of the detection device rotating and descending under the action of the traveling mechanism, the image acquisition device 3 collects data on the upper surface of the thread of the bolt hole; then the image acquisition device 3 is tilted downward, and during the process of the detection device rotating and ascending under the action of the traveling mechanism, the image acquisition device 3 collects data on the lower surface of the thread of the bolt hole.

[0049] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A thread defect detection device suitable for multi-diameter bolt holes, comprising an image acquisition device, characterized in that: Also includes: A mounting base, on which the image acquisition device is mounted, and the mounting base is connected to the walking mechanism via a connector; as well as The pitch angle adjustment component is connected between the connector and the mounting base, and is used to adjust the pitch angle of the image acquisition device to respectively capture images of the upper and lower surfaces of the threads.

2. The thread defect detection device for multi-diameter bolt holes according to claim 1, characterized in that: The detection device also includes a tilt angle adjustment component for adjusting the tilt angle of the image acquisition device; when the pitch angle of the image acquisition device is adjusted, the image acquisition device rotates around a first axis perpendicular to the axis of the bolt hole, and when the tilt angle of the image acquisition device is adjusted, the image acquisition device rotates around a second axis, and the second axis is perpendicular to the first axis and the axis of the bolt hole respectively.

3. The thread defect detection device for multi-diameter bolt holes according to claim 1, characterized in that: The detection device also includes a sliding adjustment component for adjusting the distance between the image acquisition device and the axis of the bolt hole.

4. The thread defect detection device for multi-diameter bolt holes according to claim 3, characterized in that: The sliding adjustment component is a linear module, the sliding part of the linear module is connected to the pitch angle adjustment component, and the fixed part of the linear module is connected to the connector.

5. The thread defect detection device for multi-diameter bolt holes according to any one of claims 1 to 4, characterized in that: The pitch angle adjustment assembly includes a pitch fixing seat, a pitch adjustment plate, and a pitch driving element, wherein the pitch fixing seat is connected to the connector, the mounting seat is connected to the pitch adjustment plate, one end of the pitch adjustment plate is rotatably connected to the pitch fixing seat, and the pitch driving element is used to drive the pitch adjustment plate to rotate; The tilt angle adjustment assembly includes a tilt fixing seat, a tilt adjustment plate and a tilt driving element. The tilt fixing seat is fixedly connected to the pitch fixing seat, the connecting head is fixedly connected to the tilt adjustment plate, one end of the tilt adjustment plate is rotatably connected to the tilt fixing seat, and the tilt driving element is used to drive the tilt adjustment plate to rotate.

6. The thread defect detection device for multi-diameter bolt holes according to claim 5, characterized in that: A pitch fixed rotating shaft is passed through one end of the pitch adjustment plate, both ends of the pitch fixed rotating shaft are passed through the pitch fixing seat and one end is provided with a pitch fixed rotating gear. A pitch movable rotating shaft is passed through the middle of the pitch adjustment plate, and pitch guide arc grooves are provided on both sides of the pitch fixing seat. Both ends of the pitch movable rotating shaft are passed through the pitch guide arc grooves, and one end of the pitch movable rotating shaft is provided with a pitch movable gear meshing with the pitch fixed rotating gear. One end of the tilt adjustment plate is provided with a tilt fixed rotating shaft, both ends of the tilt fixed rotating shaft are provided on the tilt fixed seat and one end is provided with a tilt fixed rotation gear, the middle part of the tilt adjustment plate is provided with a tilt movable rotating shaft, both sides of the tilt fixed seat are provided with tilt guide arc grooves, both ends of the tilt movable rotating shaft are provided in the tilt guide arc grooves, and one end of the tilt movable rotating shaft is provided with a tilt movable gear engaged with the tilt fixed rotation gear.

7. The thread defect detection device for multi-diameter bolt holes according to claim 6, characterized in that: One end of the pitch movable shaft away from the pitch movable gear and one end of the tilt movable shaft away from the tilt movable gear are both provided with locking wheels, and a locking component capable of limiting the rotation of the locking wheels is provided on the outer sides.

8. The thread defect detection device for multi-diameter bolt holes according to claim 7, characterized in that: The locking component includes an electromagnet, and the locking wheel is a permanent magnet. The locking wheel is fixed in the circumferential direction and can be axially displaced and sleeved on the pitch movable rotating shaft or the tilt movable rotating shaft.

9. The thread defect detection device for multi-diameter bolt holes according to any one of claims 1 to 4, characterized in that: The mounting seat is provided with a distance detection element for detecting the distance between the image acquisition device and the threaded surface of the bolt hole.

10. A method for detecting thread defects in bolt holes, using the thread defect detection device for multi-diameter bolt holes according to any one of claims 1 to 9, characterized in that: During the process of the detection device rotating and descending under the action of the walking mechanism, the pitch angle of the image acquisition device is adjusted so that it collects data of one of the upper and lower surfaces of the threaded bolt hole; during the process of the detection device rotating and ascending under the action of the walking mechanism, the pitch angle of the image acquisition device is adjusted so that it collects data of the other of the upper and lower surfaces of the threaded bolt hole.

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