CN201689078U - Apparatus for modulating magnetostriction to detect longitudinal static magnetic field - Google Patents
Apparatus for modulating magnetostriction to detect longitudinal static magnetic field Download PDFInfo
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- CN201689078U CN201689078U CN2010202207884U CN201020220788U CN201689078U CN 201689078 U CN201689078 U CN 201689078U CN 2010202207884 U CN2010202207884 U CN 2010202207884U CN 201020220788 U CN201020220788 U CN 201020220788U CN 201689078 U CN201689078 U CN 201689078U
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- 230000003068 static effect Effects 0.000 title claims abstract description 12
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 128
- 229910052742 iron Inorganic materials 0.000 claims abstract description 64
- 230000001105 regulatory effect Effects 0.000 claims description 24
- 238000001514 detection method Methods 0.000 claims description 19
- 230000008878 coupling Effects 0.000 claims description 13
- 238000010168 coupling process Methods 0.000 claims description 13
- 238000005859 coupling reaction Methods 0.000 claims description 13
- 239000000463 material Substances 0.000 claims description 4
- 229910000838 Al alloy Inorganic materials 0.000 claims description 3
- 239000000956 alloy Substances 0.000 claims description 3
- 238000000034 method Methods 0.000 abstract description 11
- 238000006243 chemical reaction Methods 0.000 abstract description 6
- 230000005381 magnetic domain Effects 0.000 abstract description 2
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- 230000000694 effects Effects 0.000 description 6
- 230000004907 flux Effects 0.000 description 6
- 238000010276 construction Methods 0.000 description 2
- 230000005415 magnetization Effects 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 229910001172 neodymium magnet Inorganic materials 0.000 description 1
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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Abstract
The utility model discloses an apparatus for modulating magnetostriction to detect longitudinal static magnetic field, including magnetostrictive sensor components, longitudinal static biased magnetic field components and a micrometer adjusting device. The anchor rod to be detected is mounted in the coil axle hole of the magnetostrictive sensor component; two replaceable saddle slices in the longitudinal static biased magnetic field components are arranged at both sides of the magnetostrictive sensor component to contact to the anchor rod to be detected; the micrometer adjusting device can modulate the magnetic path loop air gap distance between the two lower soft iron magnet yokes. The utility model proposes to modulate the size of the permanent magnet bias magnetic field by controlling the size of the magnetic path loop air gap, so that the gap size can be measured, and the making is definite. The exciter coil and the receiver coil are placed in a same biased magnetic field, so that the magnetic domain deflecting angles in the anchor rod are identical, and has optimum mechanical energy and electric energy conversion efficiency, the use and operation of the method is simple and safe.
Description
Technical field
The utility model relates to a kind of the cannot-harm-detection device, is specifically related to a kind of device of regulating magnetostrictive detection of longitudinal static magnetic field.
Background technology
Compare with traditional anchor pole detection method, the magnetic striction wave guide sensing range is big, the accuracy of detection height, especially can detect the conventional sense method can't detected zone, magnetic striction wave guide detects and need not coupling simultaneously, simple to operate, can be under rugged surroundings such as high temperature corrosion long-term state-detection.Based on these advantages, magnetic striction wave guide detects and is widely used in the anchor rod anchored engineering detecting of engineerings such as water conservancy and hydropower, urban construction, road and rail construction.In the magnetic striction wave guide detection technique, suitable quiescent biasing magnetic field intensity is to realize the essential condition of detection.Wherein the effect of bias magnetic field is to guarantee that electric signal is identical with mechanical wave frequency, improves the conversion efficiency of magnetostrictive effect electric energy and mechanical energy, is to realize one of key factor that detects.In order to determine the size of biased magnetic field strength, regulate magnetostrictive effect and make detection system be operated in optimum condition, can come bias magnetic field is regulated by electromagnet or permanent magnet dual mode.The characteristics of two kinds of methods of contrast, operation electriomagnet is simple, but can introduce very big active noise, signal is produced very big interference, and permanent magnet field is stable, but the bad control of magnetic field size, use inconvenient, number of patent application 200810196822.6 proposes a kind of method of measuring guided wave testing point, but only says and can regulate permanent magnet or electromagnet can be regulated the magnetic field size, does not still provide the specific implementation method for how regulating magnetic field.
Summary of the invention
The purpose of this utility model is to provide a kind of device of regulating magnetostrictive detection of longitudinal static magnetic field, this device is applied to detect based on the anchor pole of magnetostrictive effect, excitation and receiving coil are operated in the same quiescent biasing magnetic field, the magnetized state unanimity, by regulating the quiescent biasing magnetic field intensity, regulate the conversion efficiency of sensor electric energy and mechanical energy, make detection system be operated in optimum condition.
For achieving the above object, technical solution adopted in the utility model is:
The utility model comprises magneto strictive sensor parts, vertical quiescent biasing magnetic field components and milscale regulating device; Wherein:
1) magneto strictive sensor parts; Comprise drive coil, receiving coil, coil axes, shroud sleeve, shielding end cap; In the groove at coil axes two ends, be wound with drive coil and receiving coil respectively, coil axes is installed in the shielding end cap at shroud sleeve and two ends, the termination of the lead of drive coil and receiving coil, behind the through wires hole and shielding end cap through wires hole of the guide groove coils shaft end at coil axes two ends, be connected with external circuit, tested anchor pole is installed in the coil axis hole again;
2) vertical quiescent biasing magnetic field components; Comprise two interchangeable saddle sheets, two contiguous blocks, two following soft iron yokes, two permanent magnets, go up soft iron yoke, slide block; Two interchangeable saddle sheets are arranged in the both sides of magneto strictive sensor parts and contact with tested anchor pole, every interchangeable saddle sheet is from down to being provided with contiguous block, soft iron yoke and permanent magnet down down respectively successively, establish one on the permanent magnet at two ends altogether and go up the soft iron yoke, leave the slit between two following soft iron yokes of inwardly stretching out;
3) milscale regulating device: comprise milscale, slide block and fixed block; Be provided with the slide block that an energy moves between two following soft iron yoke slits on two following soft iron yoke guide-track grooves, the slide block outside is provided with the coupling shaft that is connected with milscale, have the through hole that links to each other with coupling shaft on the miking bar, fixed block is installed in wherein on one the following soft iron yoke, after the sounding rod of milscale passes the hole of fixed block, be connected with coupling shaft on the slide block.
Described slit is the clearance of 10mm～30mm.
The arc diameter of described interchangeable saddle sheet and the contacted arc groove of anchor pole is set according to measured workpiece.
Interchangeable saddle sheet in described vertical quiescent biasing magnetic field components, contiguous block, following soft iron yoke, the slide block of going up in soft iron yoke and the milscale adjusting parts are soft iron material, and milscale and fixed block that milscale is regulated in the parts are aluminum alloy materials.
Compared with prior art, the beneficial effect that the utlity model has is:
Know-why of the present utility model is that the magnetization of bias magnetic field influences the magnetostriction conversion efficiency, and for ferrimagnet, there is similar parabolical relation in the magnetization of conversion efficiency and bias magnetic field.Tradition determines that the method for biased magnetic field strength is to determine according to deviser's experience, number of patent application 200810196822.6 proposes a kind of method of measuring guided wave testing point, but only say and to regulate permanent magnet or electromagnet can be regulated the magnetic field size, but do not provide the specific implementation method for how regulating magnetic field.The utility model proposes by the size of control magnetic circuit loop air gap and regulate permanent magnet bias magnetic field size, gap length can be surveyed, and mark is clear and definite.Drive coil and receiving coil are placed under the same bias magnetic field, make the inner magnetic domain deflection angle of anchor pole unanimity, have best mechanical energy, electric energy conversion efficiency.This method is used simple to operate, safety.
Description of drawings
Fig. 1 is the scheme of installation of magnetostriction anchor pole detection system.
Fig. 2 is the structural representation of lift magnet.
Fig. 3 is the structural representation of drive coil and receiving coil.
Fig. 4 is the detection signal that the utility model is applied to diameter 20mm anchor pole detection system.
Fig. 5 is the relation curve of air gap corresponding bias magnetic field size in loop to the detection system duty.
Among the figure: 1, anchor pole; 2, interchangeable saddle sheet; 3, contiguous block; 4, following soft iron yoke; 5, permanent magnet; 6, go up the soft iron yoke; 7, slide block 8, milscale; 9, fixed block; 10, drive coil; 11, coil axes; 12, receiving coil; 13, shroud sleeve; 14, guide-track groove; 15, boss; 16, coupling shaft; 17, coil axes through hole; 18, guide groove; 19, through wires hole; 20, shielding end cap; 21, shielding end cap through wires hole; 22, electromagnetic pulse signal; 23, first non-electromagnetic pulse signal.
Embodiment
Below in conjunction with accompanying drawing and example the utility model is further described.
As Fig. 1, Fig. 2, shown in Figure 3, the utility model comprises magneto strictive sensor parts, vertical quiescent biasing magnetic field components and milscale regulating device; Wherein:
1) magneto strictive sensor parts; Comprise drive coil 10, receiving coil 12, coil axes 11, shroud sleeve 13, shielding end cap 20; In the groove at coil axes 11 two ends, be wound with drive coil 10 and receiving coil 12 respectively, coil axes 11 is installed in the shielding end cap 20 at shroud sleeve 13 and two ends, the termination of the lead of drive coil 10 and receiving coil 12, behind the through wires hole 19 and shielding end cap through wires hole 21 of the guide groove 18 coils shaft ends at coil axes 11 two ends, be connected with receiving circuit with the external drive circuit respectively, tested anchor pole 1 is installed in coil axes 11 holes again;
2) vertical quiescent biasing magnetic field components; Comprise two interchangeable saddle sheets 2, two contiguous blocks 3, two following soft iron yokes 4, two permanent magnets 5, go up soft iron yoke 6, slide block 7; Two interchangeable saddle sheets 2 are arranged in the both sides of magneto strictive sensor parts and contact with tested anchor pole 1, every interchangeable saddle sheet 2 is from down to being provided with contiguous block, soft iron yoke 4 and permanent magnet 5 down down respectively successively, establish one on the permanent magnet 5 at two ends altogether and go up soft iron yoke 6, leave the slit between two following soft iron yokes 4 of inwardly stretching out; Quiescent biasing magnetic field by change saddle sheet 2, two contiguous blocks 3, two following soft iron yokes 4, two permanent magnets 5, go up soft iron yoke 6, slide block 7 structures are formed.Permanent magnet 5 adopts NdFeB material, and the intensity that magnetizes is N35, but is not limited to N35, can adjust according to the actual requirements, and permanent magnet 5 is shaped as cube, and size can be selected according to actual needs.Magnetizing direction is a vertical direction, about the forward of two permanent magnets opposite, permanent magnet 5 and two following soft iron yokes 4, go up the magnetic circuit that soft iron yoke 6, guide rail 7 structures form and form loops.Permanent magnet 5 sizes are unsuitable too small, can form minor loop in the permanent magnet end when undersized between the permanent magnet two-stage, make by permanent magnet 5, down soft iron yoke 4, go up that magnetic flux reduces in soft iron yoke 6, guide rail 7 loops.
3) milscale regulating device: comprise milscale 8, slide block 7 and fixed block 9; Be provided with the slide block 7 that an energy moves between two following soft iron yoke 4 slits on two following soft iron yoke guide-track grooves 14, slide block 7 outsides are provided with boss 15 and the coupling shaft 16 that is connected with milscale, have the through hole that links to each other with coupling shaft 16 on milscale 8 sounding rods, fixed block 9 is installed in wherein on one the following soft iron yoke 4, after the sounding rod of milscale 8 passes the hole of fixed block 9, be connected with coupling shaft 16 on the slide block 7.
Described slit is the clearance of 10mm～30mm.By regulating milscale 8 afterbody spirals, the miking bar is vertically moved, in moving process, coupling shaft 16 by the sounding rod band and slide block 7 moves together, and slide block moves generation loop air gap between the following soft iron yoke that makes a side and the slide block 7.The magnetic loop of make permanent magnet 5 and two following soft iron yokes 4, go up soft iron yoke 6, guide rail 7 structures being formed is blocked by the loop air gap.Form two branch roads, one by permanent magnet 5 and two following soft iron yokes 4, go up soft iron yoke 6, guide rail 7 and loop air gaps and form, other one by anchor pole 1, interchangeable saddle sheet 2, contiguous block 3, down soft iron yoke 4, permanent magnet 5, go up soft iron yoke 6 and form.Magnetic circuit will always be propagated along the little direction of magnetic resistance.Increase along with the loop air gap, the magnetic resistance of loop air gap increases, magnetic circuit is along permanent magnet 5 and two following soft iron yokes 4, last soft iron yoke 6, the shunt magnetic flux in guide rail 7 and air gap loop, loop reduces, and along anchor pole 1, interchangeable saddle sheet 2, contiguous block 3, following soft iron yoke 4, permanent magnet 5, the shunt magnetic flux in last soft iron yoke 6 loops increases, the quiescent biasing field strength increases on the anchor pole, so just will be converted into control to the control of static magnetic field field intensity to magnetic loop loop air gap distance, when the loop air gap distance is 0, magnetic circuit will be all at permanent magnet 5, two following soft iron yokes 4, last soft iron yoke 6, guide rail passes through in 7 loops, then by anchor pole 1, interchangeable saddle sheet 2, the magnetic flux of contiguous block 3 does not almost have, vertical quiescent biasing field strength on the anchor pole 1 is almost 0, when the loop air gap distance increases to maximal value gradually, the magnetic resistance of loop air gap reaches maximal value, then by permanent magnet 5, two following soft iron yokes 4, last soft iron yoke 6, the magnetic flux in guide rail 7 and air gap loop, loop reaches minimum value, and along anchor pole 1, interchangeable saddle sheet 2, contiguous block 3, following soft iron yoke 4, permanent magnet 5; The magnetic flux in last soft iron yoke 6 loops reaches maximal value.The quiescent biasing field strength reaches maximal value on the anchor pole.
Described interchangeable saddle sheet 2 is set according to measured workpiece with the arc diameter of the contacted arc groove of anchor pole.Guarantee contact matching between saddle sheet 2 and the anchor pole 1.
Derive as of the present utility model, regulate milscale 8 afterbody spirals, when the loop air gap distance is 0, magnetic circuit will be all permanent magnet 5, two following soft iron yokes 4, on soft iron yoke 6, guide rail pass through in 7 loops, the saddle sheet place magnetic line of force seldom is almost 0, externally exhibit magnetic properties not makes things convenient for the bias magnet installing/dismounting, deposits safety.
Provide an embodiment below in conjunction with content of the present utility model.
Bolt diameter is 20mm, and the clearance is 10mm between two following soft iron yokes.In drive coil 10, pass through frequency 60khz, the half-sine wave signal of number of cycles 4, by magnetostrictive effect, on anchor pole 1, motivate ultrasonic guided wave signals, the reflected signal of ultrasonic guided wave signals produces a signal that comprises the anchor pole physical message again by counter magnetostriction effect on receiving coil 12.The termination of receiving coil 12 leads connected receive circuit, the signal that collects comprises electromagnetic pulse signal 22, first non-electromagnetic pulse signal 23 through amplifying, after the signal Processing such as average, filtering, inserting oscillograph and can read signal as shown in Figure 4.The duty that the peak-to-peak value Vpp of first non-electromagnetic pulse signal 23 comes the mark sensor system in the record diagram 4, by regulating milscale 8 afterbody spirals, the miking bar is vertically moved, in moving process, coupling shaft 16 by the sounding rod band and slide block 7 moves together, slide block moves the following soft iron yoke that makes a side and the generation loop air gap of slide block 7 changes, vertical quiescent biasing magnetic field size on the anchor pole 1 is along with changing, and the peak-to-peak value Vpp of first non-electromagnetic pulse signal 23 is along with changing.The Vpp value of record different circuit air gap value correspondence obtains down relation curve Fig. 5 that soft iron yoke 4 and slide block 7 gaps and anchor pole detect received signal, and anchor pole 1 vertical quiescent biasing magnetic field value of Vpp maximal value corresponding point is the optimum Working of this system.
Claims (4)
1. a device of regulating magnetostrictive detection of longitudinal static magnetic field is characterized in that: comprise magneto strictive sensor parts, vertical quiescent biasing magnetic field components and milscale regulating device; Wherein:
1) magneto strictive sensor parts; Comprise drive coil (10), receiving coil (12), coil axes (11), shroud sleeve (13), shielding end cap (20); In the groove at coil axes (11) two ends, be wound with drive coil (10) and receiving coil (12) respectively, coil axes (11) is installed in the shielding end cap at shroud sleeve (13) and two ends, the termination of the lead of drive coil (10) and receiving coil (12), behind the through wires hole and shielding end cap through wires hole of the guide groove coils shaft end at coil axes (11) two ends, be connected with receiving circuit with the external drive circuit respectively, tested anchor pole (1) is installed in coil axes (11) hole again;
2) vertical quiescent biasing magnetic field components; Comprise two interchangeable saddle sheets, two contiguous blocks, two following soft iron yokes, two permanent magnets, go up soft iron yoke (6), slide block (7); Two interchangeable saddle sheets are arranged in the both sides of magneto strictive sensor parts and contact with tested anchor pole (1), every interchangeable saddle sheet is from down to being provided with contiguous block, soft iron yoke and permanent magnet down down respectively successively, establish one on the permanent magnet at two ends altogether and go up soft iron yoke (6), leave the slit between two following soft iron yokes of inwardly stretching out;
3) milscale regulating device: comprise milscale (8), slide block (7) and fixed block (9); Be provided with the slide block (7) that an energy moves between two following soft iron yoke slits on two following soft iron yoke guide-track grooves, slide block (7) outside is provided with the coupling shaft (16) that is connected with milscale, have the through hole that links to each other with coupling shaft (16) on milscale (8) sounding rod, fixed block (9) is installed in wherein on one the following soft iron yoke, after the sounding rod of milscale (8) passes the hole of fixed block (9), be connected with coupling shaft (16) on the slide block (7).
2. a kind of device of regulating magnetostrictive detection of longitudinal static magnetic field according to claim 1 is characterized in that: described slit is the clearance of 10mm～30mm.
3. a kind of device of regulating magnetostrictive detection of longitudinal static magnetic field according to claim 1 is characterized in that: the arc diameter of described interchangeable saddle sheet and the contacted arc groove of anchor pole is set according to measured workpiece.
4. a kind of device of regulating magnetostrictive detection of longitudinal static magnetic field according to claim 1, it is characterized in that: the interchangeable saddle sheet in described vertical quiescent biasing magnetic field components, contiguous block, following soft iron yoke, the slide block of going up in soft iron yoke (6) and the milscale adjusting parts (7) are soft iron material, and milscale (8) and fixed block (9) that milscale is regulated in the parts are aluminum alloy materials.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010202207884U CN201689078U (en) | 2010-06-08 | 2010-06-08 | Apparatus for modulating magnetostriction to detect longitudinal static magnetic field |
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| Application Number | Priority Date | Filing Date | Title |
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| CN2010202207884U CN201689078U (en) | 2010-06-08 | 2010-06-08 | Apparatus for modulating magnetostriction to detect longitudinal static magnetic field |
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| CN201689078U true CN201689078U (en) | 2010-12-29 |
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| CN2010202207884U Expired - Lifetime CN201689078U (en) | 2010-06-08 | 2010-06-08 | Apparatus for modulating magnetostriction to detect longitudinal static magnetic field |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103582804A (en) * | 2011-03-31 | 2014-02-12 | 瑞士罗森股份有限公司 | Acoustic flowmeter |
| US9664543B2 (en) | 2012-10-01 | 2017-05-30 | Rosen Swiss Ag | Acoustic flowmeter and method for non-invasively determining the flow of a medium in an electrically conducting object |
-
2010
- 2010-06-08 CN CN2010202207884U patent/CN201689078U/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103582804A (en) * | 2011-03-31 | 2014-02-12 | 瑞士罗森股份有限公司 | Acoustic flowmeter |
| US9664543B2 (en) | 2012-10-01 | 2017-05-30 | Rosen Swiss Ag | Acoustic flowmeter and method for non-invasively determining the flow of a medium in an electrically conducting object |
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Granted publication date: 20101229 |