CN205333835U - Miniaturized unipolar fluxgate probe - Google Patents

Abstract

The utility model discloses a miniaturized unipolar fluxgate probe, include that a winding has exciting coil's magnetic core, around the coil cylinder who has induction coil and tickler to and two supporting seats and a casing. Magnetic core includes that long and thin runway type magnetic core skeleton takes soft -magnetic magnetic core with thin, thinly takes the recess that the winding of soft -magnetic magnetic core seted up on the peripheral profile of magnetic core skeleton, and magnetic core and coil cylinder support respectively between two supporting seats, and magnetic core is located coil cylinder and parallels with coil cylinder, and the casing surrounds outside coil cylinder. It has realized the great magnetic core structural design of draw ratio, has guaranteed probe axial and the axial high coincidence in magnetic field, and output signal's SNR is high, simple structure, convenient to use, the measuring of specially adapted low -intensity magnetic field sense.

Description

A kind of miniaturization single shaft fluxgate magnetic core

Technical field

This utility model relates to a kind of for low-intensity magnetic field angle detecting, miniaturization single shaft fluxgate magnetic core that major diameter is relatively larger, belongs to magnetic vector field measurement device field, ground。

Background technology

Magnetic field is changed by current Magnetic Sensor according to different magnetic transition effects, reaches the purpose to magnetic-field measurement。It is that soft magnetic core is carried out periodically supersaturation excitation by life cycle sexual intercourse varying magnetic field that fluxgate surveys magnetic technology, utilizes soft magnetic core that external magnetic field is changed into a kind of technology of signal of telecommunication output by the modulating action of excitation field。By the analysis to output electromotive force signal time-frequency characteristic, it may be determined that the size of external magnetic field, reach the purpose to weak magnetic signal measurement。

At present, for in the various sensors being applied to the observation of magnetic-field vector of the earth field, because fluxgate sensor volume is little, lightweight, noise is relatively low, and there is the feature of relatively low cost of manufacture and relatively wide-measuring range, more in magnetic-field measurement place application such as space magnetic field measurement, geological prospecting, shipboard navigation system。But because of the first-harmonic composition formed containing very big and useless transformer action in the output induction electromotive force of fluxgate sensor, in order to suppress this fundamental signal, current most methods is design difference output transducer, i.e. excitation coil differential concatenation, induction coil series aiding connection, promote transformer action induced potential to cancel out each other, and the induced signal of environmental magnetic field is overlapped mutually, i.e. so-called bimag fluxgate sensor。Fundametal compoment just can be made when the structural parameters of this bimag fluxgate sensor are full symmetric thoroughly to offset, so, it is divided into again double stick shape magnetic core sensor, toroidal core sensor and tubular magnetic core sensor etc. according to core structure form。

Summary of the invention

In order to obtain good directivity and comprehensive Noise Reduction performance, with double stick type sensor sole basis, this utility model aim to provide a kind of major diameter relatively larger, with the miniaturization single shaft fluxgate magnetic core of track-shaped magnetic core structure, with the needs that in satisfied use, magnetic probe axial direction is strong, noise is low, volume is little etc. requires。

Below in conjunction with accompanying drawing 1, the structural principle of track-shaped magnetic core is illustrated:

According to faraday electromagnetic induction principle, if excitation field changes over, generation induced voltage is by coil two ends:

$V_S=-ns\frac{dB}{dt}=-ns\frac{d}{dt}\left(\mathrm{\μ}\right(t)\·H_i)---\left(1\right)$

Wherein, n is number of inductive coil turns, and s is core cross section area, μ (t) for magnetic core alternating current encourage under time dependent function, H_iFor magnetic core inner magnet induction。

Being located at the excitation field under sinusoidal alternating current effect is H (t)=H_mSin ω t, the magnetization characteristic of magnetic core tri linear approximate representation, namely ignore hysteresis effect, and suppose that magnetic core magnetic capacity before unsaturation is constant, and magnetic capacity time saturated is 1, if tested magnetic field, outside now is H₀, fluxgate sensor second harmonic output voltage is:

$V_S=8{\mathrm{ns\μ}}_a{H}_0\frac{1}{T}\sin \frac{2{\mathrm{\πT}}_d}{T}sin\[2\left(\frac{2\mathrm{\π}}{T}\right)t\]---\left(2\right)$

Then, design an elongated relatively larger racetrack magnetic core, can be achieved with that fluxgate magnetic core size is little, noise is low, the requirement needs of high directivity。This project obtains state natural sciences fund youth's Projects (41404141), the great scientific instruments equipment of seismic industry scientific research special (201408005) and country special " exploitation of marine geomagnetic field vector measuring instrument and application " son special topic (2014YQ100817-2) is subsidized jointly。

This utility model is realized by techniques below:

A kind of miniaturization single shaft fluxgate magnetic core, including a magnetic core array being wound with excitation coil, is wound with the coil tube of induction coil and feedback coil, and two supporting seats and a housing；Magnetic core array includes elongated racetrack magnetic core framework and strip soft magnetic core, and the circumference around magnetic core framework has groove, and strip soft magnetic core is wrapped in groove, and it is ten layers that strip soft magnetic core is wound around the number of plies；Magnetic core array and coil tube are respectively supported between two supporting seats, and magnetic core array is positioned at coil tube and parallels with coil tube, and one of them supporting seat is additionally provided with cable-through hole, and winding wire is drawn by cable-through hole；Housing and two supporting seats are tightly connected, and housing is enclosed in outside coil tube。

The respectively segmentation coiling of described induction coil and feedback coil。

The number of plies of described induction coil is more than one layer；The number of plies of described feedback coil is more than one layer。

Said two supporting seat is divided into top braces seat and bottom support seat, top braces seat includes circular lid and first cylinder of a lamellar, the inner face of circular lid is provided with the first concentric round boss, first round boss is provided with a bracer, and the center of the first round boss is provided with cable-through hole；First cylinder is fixed on a bracer, and a bracer highlights outside the first cylinder, and the first cylindrical end face is provided with the first horizontal draw-in groove, and the bottom center of the first draw-in groove is provided with and the through hole of cable-through hole dead in line；Bottom support seat includes circular pedestal and second cylinder of a lamellar, the inner face of circular pedestal is provided with the second concentric round boss, second cylinder is vertically fixed on the second round boss, second cylinder and the second round boss dead in line, the second cylinder end face is provided with the second horizontal draw-in groove；Magnetic core array two ends are held in the first draw-in groove and the second draw-in groove respectively；Coil tube one end is enclosed within the first cylinder and end face is supported on a prominent bracer, and the coil tube other end is enclosed within the second cylinder and end face is supported on the end face of the second round boss；Housing is a cylinder, and cylinder one end is enclosed within the first round boss and end face is connected with the inner face of circular lid, and the cylinder other end is enclosed within the second round boss and end face is connected with the inner face of circular pedestal。

The root of described first round boss and the second round boss is respectively equipped with sealed groove。

The beneficial effect of a kind of miniaturization single shaft fluxgate magnetic core described in the utility model includes:

1, the racetrack core structure that major diameter is relatively larger is adopted, it is achieved that the uniaxial magnetic open gate axial high directivity of probe, footpath value are little, the instructions for use that noise is low。

2, strip soft magnetic core adopts 1J86 permalloy strip soft magnetic materials to make, and after being wound around ten layers, through 1100 degree of the high temperature anneal, can obtain high permeability, low-coercivity performance on GH128 magnetic core framework。

3, coil former is wound with multilamellar, multisection type induction coil and feedback coil respectively, the distribution capacity of coil can be reduced, improve the sensitivity of sensor。

4, two supporting seats are utilized to be attached fixing by magnetic core array, coil tube and housing, simple in construction, compact, easy to connect, firm。

5, cylindric profile is carried simple, easy to use。

Accompanying drawing explanation

Fig. 1 is the structural principle schematic diagram of racetrack fluxgate magnetic core array；

Fig. 2 is overall assembling process schematic of the present utility model；

Fig. 3 is the structural representation of top braces seat in this utility model；

Fig. 4 is the structural representation of bottom support seat in this utility model。

Detailed description of the invention

Below in conjunction with accompanying drawing 2, Fig. 3 and Fig. 4, this utility model is further described:

A kind of miniaturization single shaft fluxgate magnetic core described in the utility model, including a magnetic core array being wound with excitation coil 4, is wound with the coil tube 8 of induction coil and feedback coil, and two supporting seats and a housing。Two supporting seats are divided into top braces seat and bottom support seat。

Magnetic core array includes elongated racetrack magnetic core framework 3 and strip soft magnetic core 10, and the circumference around magnetic core framework 3 has groove, and strip soft magnetic core 10 is wrapped in groove。Magnetic core framework 3 selects the GH128 nickel-base alloy with high-ductility, higher durable creeping intensity and good oxidation resistance and the performance such as punching press, welding as framework material。In order to obtain bigger slenderness ratio, in this example, the length of the intermediate straight portion of racetrack magnetic core framework 3 is 51mm, and the internal diameter of two camber line is 2.5mm, external diameter is 4.5mm。Strip soft magnetic core 10 adopts 1J86 permalloy strip soft magnetic materials to make, and after being wound around ten layers, through 1100 degree of the high temperature anneal, can obtain high permeability, low-coercivity performance in the groove of racetrack magnetic core framework 3。Excitation coil 4 is wrapped in outside magnetic core framework 3 one layer, and the wire diameter of excitation coil 4 is 0.15mm。

Coil tube 8 adopts enhancement type polycarbonate material to make。In order to reduce the distribution capacity of induction coil and feedback coil, improve the sensitivity of sensor, in this example, induction coil and feedback coil adopt the mode of segmentation coiling to be made up of five sections of coils respectively, each spacer segment 1mm, induction coil is placed in nexine, and one has six layers, total number of turns n1=(100+100+109+100+100) * 6=3054 circle；Feedback coil is placed in outer layer, a total two-layer, total number of turns n2=(100+100+109+100+100) * 2=1018 circle。

Top braces seat includes circular lid 1 and first cylinder 7 of a lamellar, and the inner face of circular lid 1 is provided with the first concentric round boss 5, and the first round boss 5 is provided with a bracer 6, and the first round boss 5 and a bracer 6 are structure as a whole。First cylinder 7 is fixed on a bracer 6, and the first cylinder 7 is perpendicular with the inner face of circular lid 1, and a bracer 6 highlights outside the first cylinder 7, and the end face of the first cylinder 7 is provided with the first horizontal draw-in groove 13。Passing for convenience of coil lead, be provided with cable-through hole at the center of the first round boss 5, the bottom center at the first draw-in groove 13 is provided with and the through hole of cable-through hole dead in line。

Bottom support seat includes circular pedestal 2 and second cylinder 12 of a lamellar, the inner face of circular pedestal 2 is provided with the second concentric round boss 11, second cylinder 12 is vertically fixed on the second round boss 11, second cylinder 12 and the second round boss 11 dead in line, the second cylinder 12 end face is provided with the second horizontal draw-in groove 14。

During installation, magnetic core array two ends are held in the first draw-in groove 13 and the second draw-in groove 14 respectively, coil tube 8 one end is enclosed within the first cylinder 7 and end face is supported on a prominent bracer 6, coil tube 8 other end is enclosed within the second cylinder 12 and end face is supported on the end face of the second round boss 11, magnetic core array is positioned at coil tube 8 and parallels with coil tube 8, and magnetic core array and the coil lead on coil tube 8 guide to top braces seat outer end respectively through through hole and cable-through hole。For improving the stability connected, the diameter of the first cylinder 7 and the second cylinder 12 is close to the diameter of coil tube 8, so that coil tube 8 is formed respectively comparatively coordinate closely with the first cylinder 7 and the second cylinder 12。Housing is a cylinder 9, cylinder 9 one end is enclosed within the first round boss 5 and end face is connected with the inner face of circular lid 1, cylinder 9 other end is enclosed within the second round boss 11 and end face is connected with the inner face of circular pedestal 2, cylinder 9 is enclosed in outside coil tube 8, and coil tube 8 is sealed by cylinder 9 together with top braces seat and bottom support seat。For improving the compactness that cylinder 9 seals, root at the first round boss 5 and the second round boss 11 further respectively has sealed groove, sealed groove can be put into sealing ring or smear fluid sealant so that between cylinder 9 and top braces seat and bottom support seat, forming excellent sealing。So far, whole miniaturization single shaft fluxgate magnetic core is completed。

Claims (5)

1. a miniaturization single shaft fluxgate magnetic core, it is characterised in that include a magnetic core array being wound with excitation coil, is wound with the coil tube of induction coil and feedback coil, and two supporting seats and a housing；Described magnetic core array includes elongated racetrack magnetic core framework and strip soft magnetic core, and the circumference around magnetic core framework has groove, and strip soft magnetic core is wrapped in groove, and it is ten layers that strip soft magnetic core is wound around the number of plies；Described magnetic core array and coil tube are respectively supported between two supporting seats, and magnetic core array is positioned at coil tube and parallels with coil tube, and one of them supporting seat is additionally provided with cable-through hole, and winding wire is drawn by cable-through hole；Described housing and two supporting seats are tightly connected, and housing is enclosed in outside coil tube。

2. a kind of miniaturization single shaft fluxgate magnetic core according to claim 1, it is characterised in that described induction coil and feedback coil respectively segmentation coiling。

3. a kind of miniaturization single shaft fluxgate magnetic core according to claim 1, it is characterised in that the number of plies of described induction coil is more than a layer；The number of plies of described feedback coil is more than one layer。

4. a kind of miniaturization single shaft fluxgate magnetic core according to claim 1, it is characterized in that, said two supporting seat is divided into top braces seat and bottom support seat, described top braces seat includes circular lid and first cylinder of a lamellar, the inner face of circular lid is provided with the first concentric round boss, first round boss is provided with a bracer, and the center of the first round boss is provided with cable-through hole；Described first cylinder is fixed on a bracer, and a bracer highlights outside the first cylinder, and the first cylindrical end face is provided with the first horizontal draw-in groove, and the bottom center of the first draw-in groove is provided with and the through hole of cable-through hole dead in line；Described bottom support seat includes circular pedestal and second cylinder of a lamellar, the inner face of circular pedestal is provided with the second concentric round boss, second cylinder is vertically fixed on the second round boss, second cylinder and the second round boss dead in line, the second cylinder end face is provided with the second horizontal draw-in groove；Described magnetic core array two ends are held in the first draw-in groove and the second draw-in groove respectively；Described coil tube one end is enclosed within the first cylinder and end face is supported on a prominent bracer, and the coil tube other end is enclosed within the second cylinder and end face is supported on the end face of the second round boss；Described housing is a cylinder, and cylinder one end is enclosed within the first round boss and end face is connected with the inner face of circular lid, and the cylinder other end is enclosed within the second round boss and end face is connected with the inner face of circular pedestal。

5. a kind of miniaturization single shaft fluxgate magnetic core according to claim 4, it is characterised in that the root of described first round boss and the second round boss is respectively equipped with sealed groove。