CN109029382A - A kind of screw retention early warning and monitoring device - Google Patents
A kind of screw retention early warning and monitoring device Download PDFInfo
- Publication number
- CN109029382A CN109029382A CN201810949242.3A CN201810949242A CN109029382A CN 109029382 A CN109029382 A CN 109029382A CN 201810949242 A CN201810949242 A CN 201810949242A CN 109029382 A CN109029382 A CN 109029382A
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- early warning
- monitoring device
- screw retention
- bolt
- information
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C11/00—Photogrammetry or videogrammetry, e.g. stereogrammetry; Photographic surveying
- G01C11/04—Interpretation of pictures
- G01C11/06—Interpretation of pictures by comparison of two or more pictures of the same area
- G01C11/12—Interpretation of pictures by comparison of two or more pictures of the same area the pictures being supported in the same relative position as when they were taken
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- Engineering & Computer Science (AREA)
- Multimedia (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Length Measuring Devices By Optical Means (AREA)
Abstract
The present invention relates to a kind of screw retention early warning and monitoring devices, the device includes being sticked to have on the end face of screw thread one end and have the paster of photogrammetric mark in bolt to be detected and to detect paster information, the photography communication component of displacement and corner, the photography communication component includes upper casing and lower casing interconnected, the lower casing be located on bolt to be detected, it which is provided with the micro-lens and light compensating lamp with the setting of paster face, the upper casing is equipped with processing chip, signal antenna and wireless communication module, the processing chip respectively with signal antenna, wireless communication module, micro-lens is connected with light compensating lamp.Compared with prior art, the present invention has many advantages, such as that simple installation, solid and reliable, stability is high, accuracy is high, timeliness is high, economy is high.
Description
Technical field
The present invention relates to bolt looseness detection fields, more particularly, to a kind of screw retention early warning and monitoring device.
Background technique
It is commonplace by the high-strength bolt of luffing pulling force effect to be there is loosening problem in engineering.For example, large-scale wind generating
It is 100% artificial detection that the high-strength bolt of tower, which just needed single sample rate every 3-6 months,.
The loosening of high-strength bolt will cause the increase of the stress amplitude of the bolt on the bolt and periphery, form fatigue life substantially
The vicious circle of shortening finally leads to Important Project accident.Meanwhile the loosening of bolt can also repeatedly extrude the place of cracking of flange,
Cause flange to corrode to destroying corrosion-inhibiting coating, damage generated to structure, thus the dynamic monitoring that loosens of high-strength bolt at
For a major issue of engineering circles.
The method that engineering circles are monitored based on the high-strength bolt of image processing techniques at present, Chinese patent CN201110030989
The bolt looseness monitoring device and its monitoring method that a seed nucleus main pump uses are disclosed, this method is on the side of flange bolt, edge
Annular setting multiple cameras, the rotation situation of each bolt is shot from side.It is shot more at a distance due to being, therefore the party
The bracket installation of method is complicated, imaging requires height to light filling, while also having higher stabilization to the laying space enrironment of imaging device
Property with unobstructed requirement, application cost is high, it is difficult to widespread adoption.
Summary of the invention
It is an object of the present invention to overcome the above-mentioned drawbacks of the prior art and provide a kind of screw retention early warning
Monitoring device.
The purpose of the present invention can be achieved through the following technical solutions:
A kind of screw retention early warning and monitoring device, the device include being sticked in bolt to be detected on the end face of screw thread one end
And with photogrammetric mark paster and the photography communication component to detect paster information, displacement and corner, it is described
Communication component of photographing includes upper casing and lower casing interconnected, and the lower casing be located on bolt to be detected, thereon
Equipped with the micro-lens and light compensating lamp being arranged with paster face, the upper casing is equipped with processing chip, signal antenna and wireless
Communication module, the processing chip are connect with signal antenna, wireless communication module, micro-lens and light compensating lamp respectively.
The top of upper casing is arranged in the signal antenna, is additionally provided with switch button and power supply at the top of the upper casing
Interface.
Offer interconnected nut cavity and detection cavity in the lower casing, the nut cavity outside diameter with
The nut outer diameter of bolt to be detected is identical, and the micro-lens and light compensating lamp are arranged at detection cavity top.
The lower casing outer rim is equipped with the Quick release to engage.
The upper casing and lower casing is engineering plastics or Al-alloy casing.
The photogrammetric mark is the fan-shaped one-dimensional code mark of concentric ring type, and the concentric circles including centrally disposed place is fixed
Bit flag point and around the fan-shaped one-dimension code being arranged in around position mark point coding member.
The position mark point is made of multiple chequered with black and white concentric circles, and the coding member of the fan-shaped one-dimension code is by four
The fan-shaped figure spot permutation and combination of the different angles of kind is formed, and each sector figure spot is made of three wide figure spots and three narrow figure spots,
Respectively narrow black, narrow white, wide black and width white.
The distribution that the index information that the coding member of each sector one-dimension code includes passes through width figure spot under different coding multiplying power
And the configuration of black-white colors determines, the coding multiplying power is the angle ratio of wide figure spot and narrow figure spot.
The index information corresponds to the id information that the index point is stored in encoder dictionary, the information of the encoder dictionary
Including number, letter and additional character, the number is to compile to generate encoded information, the additional character with letter
The white space of symbol upper left side fourth quadrant position, for the start-stop of coding and the mark of calibration information.
Compared with prior art, the invention has the following advantages that
One, simple installation: upper and lower enclosure is fixed on nut by Quick release, and internal wiring only needs a power supply line.
Two, solid and reliable: lower casing is fixed on nut by Quick release, will not fall off under the vibration of blower bolt or
It loosens.
Three, stability is high: shooting, light filling are all in lower casing, without considering the complicated daylighting factor in scene to imaging
It influences.
Four, accuracy is high: comparing the rotational angle of photogrammetric index point by taking pictures, directly obtains the loosening angle of nut
Degree, and each code identification information corresponds to the id information of each measuring point.
Five, timeliness is high: the present invention can more densely, arrange measuring point on a large scale, and high frequency acquire data, because
This prevention to bolt looseness, more than manually periodically spot-check it is more accurate with it is timely.
Six, economy is high: checking bolt looseness, this monitoring device economy with higher compared to tower is manually continually stepped on
Property, greatly reduce expensive human input.
Detailed description of the invention
Fig. 1 is the device entirety orthogonal view for being installed on bolt.
Fig. 2 is the sectional view of the side B-B in Fig. 1.
Fig. 3 is the sectional view of the side A-A in Fig. 1.
Fig. 4 is photogrammetric code identification figure.
Fig. 5 is the fan-shaped coding member for constituting photogrammetric code identification.
Description of symbols in figure:
1, bolt head, 2, bolt, 3, nut, 4, nut shim, 5, upper flange plate, 6, lower flange plate, 7, lower casing, 8, on
Casing, 9, signal antenna, 10, power interface, 11, switch button, 12, micro-lens, 13, light compensating lamp, 14, photogrammetric mark
Point paster, 15, Quick release, 16, multiple fan-shaped first one-dimension codes constituted of coding, 17 be concentric circles position mark point, 18, wide figure
Spot, 19, narrow figure spot.
Specific embodiment
The present invention is described in detail with specific embodiment below in conjunction with the accompanying drawings.
Embodiment
The present invention provides a kind of screw retention early warning and monitoring device.In the top of nut, button sets a terminal, and in terminal
Middle insertion a whole set of light filling, imaging, wireless communication transmissions, image data processor and power supply system.
The present apparatus is mounted on nut, is laid in the photogrammetric index point of screw rod top surface, by shooting to recognize nut
It is transmitted back to monitoring base station relative to the rotational angle between bolt, and by the testing result of transmission of angle, to realize long-range prison
The loosening corner for controlling bolt, further calculates the actual time safety state for obtaining structure.
The bolt that bolt head 1 and bolt 2 are integrally formed in device installation, nut 3 are pressed on nut shim 4, simultaneously
Nut 3 is screwed into bolt 2 and is fastened to specified stress standard according to construction demand；Upper flange plate 5 is to need to pass through with lower flange plate 6
The structural member that bolt is linked is compressed by the system that nut shim 4 and nut 3 form.Lower casing 7 and 8 material of upper casing
For engineering plastics or aluminium alloy, needs first to be buckled in lower casing 7 on nut 3 by Quick release 15 when in use, then pass through upper machine
Lower casing 7 and upper casing 8 are combined fixation by subsidiary hickey on shell 8.Photogrammetric index point paster 14 is attached to spiral shell
The top of bolt 2.Micro-lens 12 and light compensating lamp 13 are embedded in 8, are made up of light compensating lamp 13 to lower casing 7 and upper casing 8
Internal chamber carries out light filling, is then carried out by micro-lens 12 to the photogrammetric index point paster 14 for being affixed on 2 top of bolt
Imaging.
In device in use, first by being preset in the power interface 10 at 8 top of upper casing, grafting enters DC power supply, so
Pass through 11 starter of switch button afterwards.At this time micro-lens 12 can to photogrammetric index point paster 14 carry out for the first time at
Then picture carries out the decoding process of code identification by processing chip built-in in upper housing 8, obtain photogrammetric index point patch
The initial displacement and rotation angle of paper 14, as the displacement and angle value initially installed.In use, 12 meeting of micro-lens
It is constantly imaged according to the specified period to 14, and resolves the real-time displacement and rotation angle of photogrammetric index point paster 14
Degree, and by being compared with the displacement initially installed with angle value, metric photography measures spiral shell representated by index point paster 14
Displacement and corner between bolt 2 and nut 3 change.
When the displacement and corner measured is greater than given alarm threshold, that is, think that current bolt has been in loosening shape
State, loosens angle by the loosening warning for sending bolt by signal antenna 9 and specifically at this time, and signal antenna 9 is installed on machine
The top of shell 8 is connected with reserved female mouth.
The metric photography measurement index point paster 14 pasted on each bolt all has the unique coding for representing the bolt
Mark, can indicate the id information of bolt.Pattern on the index point paster 14 of metric photography measurement simultaneously is provided for being displaced and revolving
Turn the mark of measurement；It is logical first after obtaining the coded image that metric photography measures index point paster 14 by micro-lens 12
Pretreatment is crossed, bianry image only containing marginal information is obtained from the coding maker image of input.Then basis only contains side
The bianry image of edge information obtains the central point of coding maker using the ellipse fitting adjustment Algorithm of least square, and with central point
Pixel coordinate as work as front bolt shift value.Then centered on central point, using the arc searching method of given radius,
The black and white gray value search that 360 degree are carried out with given radius is converted to the fan-shaped coding maker for encoding member composition one-dimensional
After the coding of bar code, according to the corresponding angle of each coding member of encoder dictionary, when monochrome pixels value carries out traversal matching, obtains
Complete encoded information value is taken, corresponding decoding is completed.After completing decoding, improved Fourier-Mellin transform can be used and calculate
Method resolves the rotation occurred on the position mark point for encoding member in two images with translational movement.Or pass through two-dimentional straight line
Hough transformation the linear edge of fan-shaped figure spot is extracted, then using least square to representated by a plurality of linear edge
Rotation angle is resolved.
Claims (9)
1. a kind of screw retention early warning and monitoring device, which is characterized in that the device includes being sticked in bolt to be detected (2) with spiral shell
On the end face of line one end and with photogrammetric mark paster (14) and to detect paster (14) information, displacement and corner
Photography communication component, the photography communication component includes upper casing interconnected (8) and lower casing (7), the lower machine
Shell (7) be located on bolt to be detected, which is provided with micro-lens (12) and light compensating lamp (13) with the setting of paster (14) face,
The upper casing (8) is equipped with processing chip, signal antenna (9) and wireless communication module, the processing chip respectively with letter
Number antenna (9), wireless communication module, micro-lens (12) and light compensating lamp (13) connection.
2. a kind of screw retention early warning and monitoring device according to claim 1, which is characterized in that the signal antenna
(9) setting is additionally provided with switch button (11) and power interface (10) at the top of the top of upper casing (8), the upper casing (8).
3. a kind of screw retention early warning and monitoring device according to claim 1, which is characterized in that the lower casing (7)
Inside offer interconnected nut cavity and detection cavity, the nut of the nut cavity outside diameter and bolt to be detected (2)
(3) outer diameter is identical, and the micro-lens (12) and light compensating lamp (13) are arranged at detection cavity top.
4. a kind of screw retention early warning and monitoring device according to claim 1, which is characterized in that the lower casing (7)
Outer rim is equipped with the Quick release (15) to engage.
5. a kind of screw retention early warning and monitoring device according to claim 1, which is characterized in that the upper casing (8)
It is engineering plastics or Al-alloy casing with lower casing (7).
6. a kind of screw retention early warning and monitoring device according to claim 1, which is characterized in that the photogrammetric mark
Will is the fan-shaped one-dimensional code mark of concentric ring type, concentric circles position mark point including centrally disposed place and around setting fixed
The coding member of fan-shaped one-dimension code around bit flag point.
7. a kind of screw retention early warning and monitoring device according to claim 6, which is characterized in that the position mark point
It is made of multiple chequered with black and white concentric circles, the coding member of the fan-shaped one-dimension code is arranged by the fan-shaped figure spot of four kinds of different angles
Combination is formed, and each sector figure spot is made of three wide figure spots and three narrow figure spots, and respectively narrow black, narrow white, width are black
Color and width white.
8. a kind of screw retention early warning and monitoring device according to claim 7, which is characterized in that each sector one-dimension code
The index information that coding member includes passes through the distribution of width figure spot under different coding multiplying power and the configuration decision of black-white colors, institute
The coding multiplying power stated is the angle ratio of wide figure spot and narrow figure spot.
9. a kind of screw retention early warning and monitoring device according to claim 8, which is characterized in that the index information pair
The id information that the index point is stored in encoder dictionary is answered, the information of the encoder dictionary includes number, letter and special symbol
Number, the number is to encode first upper left side fourth quadrant position to generate encoded information, the additional character with letter
White space, for the start-stop of coding and the mark of calibration information.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810949242.3A CN109029382B (en) | 2018-08-20 | 2018-08-20 | Bolt looseness-prevention early warning monitoring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810949242.3A CN109029382B (en) | 2018-08-20 | 2018-08-20 | Bolt looseness-prevention early warning monitoring device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109029382A true CN109029382A (en) | 2018-12-18 |
| CN109029382B CN109029382B (en) | 2023-08-08 |
Family
ID=64632105
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810949242.3A Active CN109029382B (en) | 2018-08-20 | 2018-08-20 | Bolt looseness-prevention early warning monitoring device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109029382B (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111323843A (en) * | 2020-03-17 | 2020-06-23 | 中煤科工集团重庆研究院有限公司 | Device for detecting fastening state of mining explosion-proof shell fastener |
| CN111792267A (en) * | 2020-09-09 | 2020-10-20 | 博众精工科技股份有限公司 | Stacker position detection device, system and method and storage medium |
| CN112097706A (en) * | 2020-08-24 | 2020-12-18 | 中国大唐集团科学技术研究院有限公司西北电力试验研究院 | Wind power tower cylinder flange bolt looseness real-time monitoring system and early warning method |
| CN112414683A (en) * | 2019-12-24 | 2021-02-26 | 湖南科技大学 | Mean mahalanobis distance-based loose bolt position positioning method and system |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112414683A (en) * | 2019-12-24 | 2021-02-26 | 湖南科技大学 | Mean mahalanobis distance-based loose bolt position positioning method and system |
| CN111323843A (en) * | 2020-03-17 | 2020-06-23 | 中煤科工集团重庆研究院有限公司 | Device for detecting fastening state of mining explosion-proof shell fastener |
| CN111323843B (en) * | 2020-03-17 | 2022-07-19 | 中煤科工集团重庆研究院有限公司 | Device for detecting fastening state of mining explosion-proof shell fastener |
| CN112097706A (en) * | 2020-08-24 | 2020-12-18 | 中国大唐集团科学技术研究院有限公司西北电力试验研究院 | Wind power tower cylinder flange bolt looseness real-time monitoring system and early warning method |
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| CN111792267B (en) * | 2020-09-09 | 2020-12-08 | 博众精工科技股份有限公司 | Stacker position detection device, system and method and storage medium |
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