CN104569874A - Signal acquisition device based on electromagnetic induction and manufacturing and use method of signal acquisition device - Google Patents
Signal acquisition device based on electromagnetic induction and manufacturing and use method of signal acquisition device Download PDFInfo
- Publication number
- CN104569874A CN104569874A CN201410847784.1A CN201410847784A CN104569874A CN 104569874 A CN104569874 A CN 104569874A CN 201410847784 A CN201410847784 A CN 201410847784A CN 104569874 A CN104569874 A CN 104569874A
- Authority
- CN
- China
- Prior art keywords
- coil
- magnetic field
- detected
- coils
- primary coil
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Abstract
The invention discloses a signal acquisition device based on electromagnetic induction and a manufacturing and use method of the signal acquisition device. According to the basic structure, the signal acquisition device comprises three coils, and according to the improved structure, a magnetic impedance sensor is arranged on the basis of the basic structure. The three coils include one primary coil and two secondary coils. The first secondary coil and the second secondary coil are located in the positions the same distance away from the two sides of the primary coil respectively, and are parallel to the primary coil. The winding directions of the two secondary coils are opposite, the turn numbers of the two secondary coils are the same, and the two secondary coils are connected end to end. The signal acquisition device is placed near a conductive object to be detected. By means of the signal acquisition device, when the frequency of an excitation signal is higher than 2 kHz, eddy current is generated in the object to be detected under the action of a primary magnetic field generated by the primary coil; a secondary magnetic field is formed by the eddy current; additional induced electromotive force is formed in the two secondary coils through the secondary magnetic field. Compared with the prior art, the gradient changes of a surrounding magnetic field can be detected, and measurement can be conducted at different depths by changing the frequency of the signal.
Description
Technical field
The present invention relates to electronic information acquisition technique, can the physical characteristics of conductive material from surface to inside for detecting.
Background technology
According to Theory of Electromagnetic Field, the electric field of change can produce magnetic field, and the magnetic field of change can produce electric field.And electromagnetic induction is just based on the mutual conversion between electric field and magnetic field.Electromagnetic induction all extensive application in electrician, electronic technology, electrification, robotization.When a given coil, coil passes to exchange current, the change in magnetic field near coil can be caused; Equally, if the magnetic field around coil changes, will be changed by the magnetic flux of coil, coil will produce induction electromotive force, the size of induction electromotive force is relevant with environment residing for coil, gathers by electronic technology, thus reaches the object of signals collecting.When the coil being loaded with exchange current is placed near conductive material, due to the electromagnetic induction of coil and conductive material, some characteristics of conductive material itself can be made, as resistivity height, whether inside has the defects such as crack is reflected.When the frequency of the exchange current loaded is higher, due to skin effect, the information of conductive material surface can be reflected; When the frequency of the exchange current loaded is lower, electromagnetic signal can be made to be deep into conductive material inside, and to reflect the information of conductive material inside.
Summary of the invention
In order to realize the detection of conductive material from surface to internal physical characteristics, the present invention proposes a kind of signal pickup assembly based on electromagnetic induction and preparation method thereof, as the new signals collecting scheme based on electromagnetic induction, when loading the signal of certain frequency on gradometer, electromagnetic induction can be produced by conductor around, and response is produced to the magnetic field of induction.Response signal is relevant with the physical state of conductor, and the difference of load signal frequency, and the degree of depth of the conductor that response signal reflects is also different.When the signal loaded is swept-frequency signal from low to high, just can realize the detection of testee from inside to surface.
The present invention proposes a kind of signal pickup assembly based on electromagnetic induction, the basic structure of this device comprises three groups of coils, i.e. one group of primary coil 3 and two groups of secondary coils; Wherein said secondary coil comprises the first secondary coil 41 and second subprime coil 42; Described first secondary coil 41 and second subprime coil 42 lay respectively at equidistant position, both sides of primary coil 3, and parallel with primary coil 3, and the first secondary coil 41 is contrary with the winding direction of second subprime coil 42, the number of turn is identical, end to end;
When said apparatus being positioned near conductive material to be detected, primary coil produces an Induced magnetic field, and material to be detected, under the effect of described Induced magnetic field, produces vortex flow; Described vortex flow forms a secondary magnetic, forms induction in described secondary magnetic wire coil around, the induced electromotive force that formation one is additional in two groups of secondary coils.
When described device is used for low frequency, being also provided with magneto-impedance sensors 8 near described first secondary coil 41 place, form a kind of modified node method.In order to ensure the duty of described magneto-impedance sensors, need to pass to direct current in secondary coil, for magneto-impedance sensors provides working point, magnetic field.
The invention allows for a kind of method for making of the signal pickup assembly based on electromagnetic induction, the method comprises the following steps:
Select dielectric cylindrical material, at equidistant coiling three groups of coils above, wherein primary coil is positioned at centre, and the first secondary coil (41) and second subprime coil (42) lay respectively at both sides.
The present invention has reintroduced the object detection using method that a kind of signal pickup assembly based on electromagnetic induction realizes, and the method comprises the following steps:
The described signal pickup assembly based on electromagnetic induction is positioned near conductive material to be detected to be detected;
When this device in the frequency of pumping signal higher than when working under 2kHz, under the primary magnetic field effect that primary coil produces, in examined object, produce vortex flow; Vortex flow also forms a secondary magnetic; This secondary magnetic all can form an additional induced electromotive force in two groups of secondary coils;
When this device in the frequency of pumping signal lower than when working under 2kHz, magneto-impedance sensors is started working, and secondary coil provides working point, magnetic field for magneto-impedance sensors simultaneously; Now, the alternating signal that primary coil loads produces vortex flow in material to be detected, and the magnetic field that this vortex flow is formed can be detected by magneto-impedance sensors, causes the change of its impedance; By the detection to magneto-impedance sensors impedance, obtain the information of material proterties to be detected.
Compared with prior art, the present invention can realize the detection to surrounding magnetic field graded, by changing the frequency of signal, can realize measuring at different depth.
Accompanying drawing explanation
Fig. 1 is the basic structure schematic diagram of the signal pickup assembly based on electromagnetic induction of the present invention; Wherein: 1, Induced magnetic field; 2, vortex flow; 3, primary coil; 4, secondary coil; 5, primary magnetic field;
Fig. 2 is the manufacturing process schematic diagram of the signal pickup assembly based on electromagnetic induction of the present invention; Wherein: 6, secondary coil winding position; 7, primary coil winding position;
Fig. 3 is the signal pickup assembly modified node method schematic diagram based on electromagnetic induction for low frequency of the present invention; Wherein: 8, magneto-impedance sensors; 3, primary coil; 41, the first secondary coil; 42, second subprime coil; 9, conductor to be measured.
Embodiment
Below in conjunction with the drawings and specific embodiments, the present invention is described in detail, but practical range of the present invention is not limited thereto.
As shown in Figure 1, the basic structure of the signal pickup assembly based on electromagnetic induction of the present invention contains three groups of coils, one group of primary coil (LP), 3, two groups of secondary coil (L
sUand L
sL) 41,42, two groups of secondary coils 41,42 lay respectively at equidistant position, both sides of primary coil 3, and parallel with primary coil 3, and the winding direction of two groups of secondary coils 41,42 is contrary, the number of turn is identical, end to end.
As shown in Figure 2, manufacturing process schematic diagram for the signal pickup assembly based on electromagnetic induction of the present invention: in order to effectively produce the gradometer meeting above-mentioned requirements, teflon cylinder can be selected when implementing, three grooves are outputed above, wherein first slot pitch is a from the distance of cylinder end face, and the distance between these three grooves is equal, is b, the width of each groove is c, and the diameter of groove is d.In these three grooves, being positioned at middle one, for being wound around primary coil, being positioned at two of both sides, for being wound around secondary coil.
The course of work of gradometer of the present invention is as follows:
When working at higher frequencies, the primary coil of the signal pickup assembly based on electromagnetic induction of the present invention loads alternating signal U
prim, according to Theory of Electromagnetic Field, the primary magnetic field that can change around primary coil, its frequency and U
primidentical.The primary magnetic field of this change is at secondary coil L
sUand L
sLin will generate induction electromotive force (Induced magnetic field), but because the winding direction of two groups of secondary coils is contrary, the number of turn is identical, so at L
sUand L
sLon induction electromotive force equal and opposite in direction, direction is contrary, and therefore the voltage of secondary coil exports U
res=0.
When said apparatus being positioned near conductive material (material to be detected), due to the effect of the alternating magnetic field that primary coil produces, will vortex current being produced in material to be detected, being called for short vortex flow.Vortex flow also can form a magnetic field, the secondary magnetic namely shown in Fig. 1.Secondary magnetic also can form induction, therefore, at two groups of secondary coil L in wire coil around
sUand L
sLin all can form an additional induced electromotive force.But because two groups of secondary coils are different from the distance of material to be detected, also there is larger difference in the induced electric field that therefore secondary magnetic is formed.Like this, the voltage of secondary coil is just made to export U
resbe no longer 0, its size to be subject to the conductivity of material to be detected, size, material to be detected and based on electromagnetic induction signal pickup assembly between the impact of the many factors such as distance, the integrated information of material proterties to be detected will be drawn after comprehensive descision.
When working at a lower frequency, magneto-impedance sensors is started working, and simultaneously secondary coil provides working point, magnetic field for magneto-impedance sensors.Now, the alternating signal that primary coil loads produces vortex flow in material to be detected, and the magnetic field that this vortex flow is formed can be detected by magneto-impedance sensors, causes the change of its impedance.Within the specific limits, the relation of changes of magnetic field and impedance variation is linear, by the detection to magneto-impedance sensors impedance, just can obtain the information of material proterties to be detected.
By changing the frequency of signal, the measurement of different depth can be realized.
In above-mentioned basic structure, the generation of induced signal is realized by electromagnetic induction, and when the frequency of pumping signal is higher, the strength of vortex of inducting is comparatively large, and secondary coil 41,42 can generate obvious electromotive force.But, due to skin effect, cross high-frequency electromagnetic wave penetration capacity more weak, the detection treating test material inside cannot be realized.The degree of depth realizing electromagnetic response in examined object is different, and like this, loading swept-frequency signal just can realize the detection from material internal to surface.In order to realize the detection to material internal, need the pumping signal using lower frequency.When the frequency of pumping signal is lower than 2kHz, because the induced electromotive force formed in secondary coil is too faint, the modified node method of this device can be applied, now secondary coil passes to direct current for magneto-impedance sensors provides working point, magnetic field, under the primary magnetic field effect that primary coil produces, in examined object, produce vortex flow; Vortex flow also forms a secondary magnetic, and this magnetic field can be detected by magneto-impedance sensors, causes the change of its impedance.
In order to obtain stronger induction result, the present invention proposes modified node method on the basis of basic structure: introduce magneto-impedance sensors, such as GMR (Giant Magneto Resistance), TMR (Tunneling MagnetoResistance), CMR (Colossal Magneto Resistance) etc., replace common secondary coil.
When the intensity generation subtle change of environmental magnetic field, the great variety of magneto-impedance sensors impedance can be caused.The magneto-impedance sensors designed according to this giant magnetoresistance effect, just may be used for the electromagnetic induction caused by pumping signal detecting lower frequency.
In order to ensure detection accuracy, magneto-impedance sensors needs certain working point, magnetic field, by arranging a coil near magneto-impedance sensors, and passes to galvanic current to realize.
As shown in Figure 3, when being applied to low frequency, the signal pickup assembly based on electromagnetic induction of the present invention has modified node method.
In addition, because the remolding sensitivity normal coil of magneto-impedance sensors under slightly high-frequency is low, so when the frequency of pumping signal is higher than a certain numerical value, such as 2kHz, detection is still based on basic structure.That is, only when the depth finding for lower frequency, magneto-impedance sensors just works with the coil for generation of working point, magnetic field, and when signal frequency reaches more than 2kHz, is converted to the mode of operation of normal coil.In order to realize the signal pickup assembly unification structurally when using High-frequency and low-frequency detectable signal based on electromagnetic induction, the specific practice that the present invention takes is, at low frequency during magnetoimpedance mode of operation, secondary coil can with direct current, be used for realizing the working point, magnetic field of magneto-impedance sensors, magneto-impedance sensors work; And at higher frequencies (as more than 2kHz) non-magnetoimpedance mode of operation time, arranged by circuit and make field impedance element invalid, secondary coil realizes induction to the change in magnetic field, is now reduced to basic structure.The position relationship of magneto-impedance sensors and coil as shown in Figure 3.
The signal pickup assembly based on electromagnetic induction proposed by the invention, when implementing, can select different parameters, such as, distance, the diameter of coil, the frequency etc. of alternating electric field between the number of turn of primary coil and secondary coil, coil.These parameters produce different impacts by the testing result of conductive material.Preferred forms: the elementary and secondary coil of coiling on teflon cylinder as shown in Figure 2.Primary coil and secondary coil all select copper paint envelope curve coiling 200 circle of diameter 0.1mm.The minimum diameter d of coil is 10mm, and the width c when coiling shared by coil is 1mm, and the spacing b of primary coil and secondary coil is 5mm, and the distance a of first level transmitter-receiver spacing cylinder end face is 1mm.
Magneto-impedance sensors selects GMR.
Although invention has been described for composition graphs above; but the present invention is not limited to above-mentioned embodiment; above-mentioned embodiment is only schematic; instead of it is restrictive; those of ordinary skill in the art is under enlightenment of the present invention; when not departing from present inventive concept, can also make a lot of distortion, these all belong within protection of the present invention.
Claims (4)
1. based on a signal pickup assembly for electromagnetic induction, it is characterized in that, the basic structure of this device comprises three groups of coils, i.e. one group of primary coil (3) and two groups of secondary coils; Wherein said secondary coil comprises the first secondary coil (41) and second subprime coil (42); Described first secondary coil (41) and second subprime coil (42) lay respectively at equidistant position, both sides of primary coil (3), and parallel with primary coil (3), and the first secondary coil (41) is contrary with the winding direction of second subprime coil (42), the number of turn is identical, end to end;
When said apparatus being positioned near conductive material to be detected, the primary coil being loaded with exchange current produces an Induced magnetic field, and material to be detected, under the effect of described Induced magnetic field, produces vortex flow; Described vortex flow forms a secondary magnetic, forms induction in described secondary magnetic wire coil around, the induced electromotive force that formation one is additional in two groups of secondary coils.
2. a kind of signal pickup assembly based on electromagnetic induction as claimed in claim 1, it is characterized in that, when described device is used for low frequency, use its modified node method, namely arranging magneto-impedance sensors near described first secondary coil (41) place, now described secondary coil passes to direct current for magnetic induction sensor provides magnetic field bias.
3. based on a method for making for the signal pickup assembly of electromagnetic induction, it is characterized in that, the method comprises the following steps:
Select dielectric cylindrical material, at equidistant coiling three groups of coils above, wherein primary coil is positioned at centre, and the first secondary coil (41) and second subprime coil (42) lay respectively at both sides.
4. utilize the object detection using method that a kind of signal pickup assembly based on electromagnetic induction described in claim 1 realizes, it is characterized in that, the method comprises the following steps:
The described signal pickup assembly based on electromagnetic induction is positioned near conductive material to be detected to be detected;
When this device in the frequency of pumping signal higher than when working under 2kHz, under the primary magnetic field effect that primary coil produces, in examined object, produce vortex flow; Vortex flow also forms a secondary magnetic; This secondary magnetic all can form an additional induced electromotive force in two groups of secondary coils;
When this device in the frequency of pumping signal lower than when working under 2kHz, magneto-impedance sensors is started working, and secondary coil provides working point, magnetic field for magneto-impedance sensors simultaneously; Now, the alternating signal that primary coil loads produces vortex flow in material to be detected, and the magnetic field that this vortex flow is formed can be detected by magneto-impedance sensors, causes the change of its impedance; By detecting the change of magneto-impedance sensors impedance, obtain the information of material proterties to be detected.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410847784.1A CN104569874A (en) | 2014-12-30 | 2014-12-30 | Signal acquisition device based on electromagnetic induction and manufacturing and use method of signal acquisition device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410847784.1A CN104569874A (en) | 2014-12-30 | 2014-12-30 | Signal acquisition device based on electromagnetic induction and manufacturing and use method of signal acquisition device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN104569874A true CN104569874A (en) | 2015-04-29 |
Family
ID=53086396
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410847784.1A Pending CN104569874A (en) | 2014-12-30 | 2014-12-30 | Signal acquisition device based on electromagnetic induction and manufacturing and use method of signal acquisition device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104569874A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108282031A (en) * | 2018-03-14 | 2018-07-13 | 南京航空航天大学 | A kind of non-contact electric energy transmission device and winding construction discrimination method |
| CN109917469A (en) * | 2019-03-14 | 2019-06-21 | 中船海洋探测技术研究院有限公司 | A kind of asymmetric highly sensitive coil Magnetic Sensor |
| CN111290032A (en) * | 2020-03-11 | 2020-06-16 | 中国石油大学(华东) | Electromagnetic-based intelligent stratum metal identification device and identification method |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101876528A (en) * | 2010-07-02 | 2010-11-03 | 天津大学 | Electromagnetic sensor-based metal film thickness measuring device and method |
| EP2493076A1 (en) * | 2011-02-22 | 2012-08-29 | Rockwell Automation Technologies, Inc. | Inductive proximity sensor |
| CN102841128A (en) * | 2012-08-20 | 2012-12-26 | 上海交通大学 | Eddy-current sensor for recognizing biological tissues |
| CN103163211A (en) * | 2013-03-14 | 2013-06-19 | 天津大学 | Classification recognition method of defects at surface and sub-surface of metallic conductor |
-
2014
- 2014-12-30 CN CN201410847784.1A patent/CN104569874A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101876528A (en) * | 2010-07-02 | 2010-11-03 | 天津大学 | Electromagnetic sensor-based metal film thickness measuring device and method |
| EP2493076A1 (en) * | 2011-02-22 | 2012-08-29 | Rockwell Automation Technologies, Inc. | Inductive proximity sensor |
| CN102841128A (en) * | 2012-08-20 | 2012-12-26 | 上海交通大学 | Eddy-current sensor for recognizing biological tissues |
| CN103163211A (en) * | 2013-03-14 | 2013-06-19 | 天津大学 | Classification recognition method of defects at surface and sub-surface of metallic conductor |
Non-Patent Citations (1)
| Title |
|---|
| 徐可北 周俊华: "《涡流检测》", 31 August 2004 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108282031A (en) * | 2018-03-14 | 2018-07-13 | 南京航空航天大学 | A kind of non-contact electric energy transmission device and winding construction discrimination method |
| CN108282031B (en) * | 2018-03-14 | 2020-01-10 | 南京航空航天大学 | Non-contact electric energy transmission device and winding structure identification method |
| CN109917469A (en) * | 2019-03-14 | 2019-06-21 | 中船海洋探测技术研究院有限公司 | A kind of asymmetric highly sensitive coil Magnetic Sensor |
| CN111290032A (en) * | 2020-03-11 | 2020-06-16 | 中国石油大学(华东) | Electromagnetic-based intelligent stratum metal identification device and identification method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107064291B (en) | Magnetic gathering pulse eddy current coil detection sensor | |
| US7705589B2 (en) | Sensor for detecting surface defects of metal tube using eddy current method | |
| CA2842888C (en) | High resolution eddy current array probe | |
| CN101140263B (en) | Electric transverse currents detecting sensor based on strong magnetic resistance and method thereof | |
| CN103196996B (en) | A kind of eddy current testing device for carrying out metal defect detection and eddy current probe thereof | |
| CN105717191A (en) | Detection method and device for magnetic Barkhausen noise signal and magnetic parameters | |
| CN201177614Y (en) | Multipurpose electromagnetical detection device based on same magnetic test coil | |
| JP2016105046A (en) | Magnetic nondestructive inspection device | |
| CN108535329A (en) | The test device of thin layer of conductive material, the test method of sheet resistance, the test method of damage information | |
| CN105548924A (en) | Magnetic Barkhausen and magnetic parameter sensor and measurement method of magnetic Barkhausen and magnetic parameter | |
| CN104569874A (en) | Signal acquisition device based on electromagnetic induction and manufacturing and use method of signal acquisition device | |
| CN104700490A (en) | Multi-model coin signal collecting device based on eddy current sensor | |
| CN109030621A (en) | The flexibility two dimension vortex sensor array and its application method of monitoring crack | |
| CN103675094A (en) | Non-destructive testing device | |
| CN101311714A (en) | High-sensitivity vortex flow dot type probe | |
| CN203673555U (en) | Multi-modal eddy current sensor coin signal collection device | |
| CN103544764B (en) | A kind of sensor for identifying magnetic medium | |
| CN102087245B (en) | Amorphous alloy based electromagnetic detection sensor | |
| CN103617669B (en) | A kind of Coin detection device | |
| CN203490758U (en) | Sensor used for identifying magnetic medium | |
| CN105319444A (en) | Method for assessing conductivity uniformity of conductive material | |
| Chao et al. | GMR based eddy current system for defect detection | |
| CN204044346U (en) | A kind of planar radio frequency coils for nuclear magnetic resonance | |
| Faraj et al. | Hybrid of eddy current probe based on permanent magnet and GMR sensor | |
| Pan et al. | Quantitative method for defect surface area of wire rope based on circumferential magnetic flux leakage image |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20150429 |