CN219369647U - High-sensitivity detection probe based on AC/DC composite excitation magnetic shielding layer - Google Patents

Abstract

The utility model provides a high-sensitivity detection probe based on an alternating current-direct current composite excitation magnetic shielding layer, which comprises a fixing screw, a gland, a signal processing circuit, U-shaped soft iron, a large magnetic shielding layer, a small magnetic shielding layer, an alternating current excitation module, a direct current excitation module, a TMR magnetic sensor, a soft rigid brush, a Lei Mo joint and a shell. The TMR magnetic sensor is arranged at the bottom of the shell, and the alternating current excitation module is arranged right above the TMR magnetic sensor and comprises an excitation coil and a U-shaped magnetic core. The direct current excitation module is two permanent magnets, the upper end of the direct current excitation module is connected with U-shaped soft iron to form a magnetic loop, the lower end of the direct current excitation module is connected with a soft rigid brush, and a magnetic field generated by the direct current excitation module is led into a tested test piece. The signal processing circuit performs amplification filtering processing on the signal output by the TMR magnetic sensor. The high-sensitivity detection probe based on the AC/DC composite excitation magnetic shielding layer is simple to operate, can distinguish surface defects from buried defects, realizes accurate identification and quantification of the defects, and reduces the error judgment rate of the defects.

Description

High-sensitivity detection probe based on AC/DC composite excitation magnetic shielding layer

Technical Field

The utility model relates to the field of detection probes, in particular to a high-sensitivity detection probe based on an AC/DC composite excitation magnetic shielding layer.

Background

The alternating current magnetic field detection (Alternating current field measurement, abbreviated as ACFM) technology is an emerging electromagnetic nondestructive detection technology, the basic principle is an electromagnetic induction principle, a sinusoidal alternating current signal is loaded on an exciting coil, an induction magnetic field is excited on the surface of a workpiece to be detected, and then induction current is generated, the induction current deflects and gathers at defect positions such as cracks, corrosion and the like, so that a space magnetic field above the defects is distorted, and a detection sensor is used for measuring a space distortion magnetic field signal, so that defect detection and evaluation are realized, but due to the existence of a skin effect, only surface defects can be detected, the detection is insensitive to buried defects, and the direct current magnetic leakage technology has strong penetrating capability and can play a good role in detecting buried defects of ferromagnetic materials. The method combines the alternating current electromagnetic field detection technology and the direct current magnetic leakage detection technology, can achieve good and rapid detection and quantitative evaluation effects on the surface and the buried depth defects of the ferromagnetic material, does not need a coupling agent between a probe and a workpiece, is simple to operate, and can be widely applied to nondestructive detection of the ferromagnetic material.

The conventional ACFM detection probe realizes the identification of surface defects through an X-direction magnetic field (BX signal) and a Z-direction magnetic field (BZ signal) obtained by scanning, but due to the existence of the skin effect of the technology, the detection of the buried defects is insensitive, the detection of the defects is missed, and the accurate analysis of detection personnel is not facilitated. The utility model designs a high-sensitivity detection probe with a magnetic shielding layer based on alternating current and direct current composite excitation based on an alternating current magnetic field detection technology and a direct current magnetic leakage detection technology, which is used for detecting the characteristics of surface defects and buried defects simultaneously by utilizing the alternating current magnetic field detection technology, separating alternating current electromagnetic field detection signals from direct current magnetic leakage signals by using Fourier transformation, carrying out signal analysis, distinguishing the surface defects from the buried defects, quantitatively evaluating the defects, realizing accurate identification of the defects and reducing the defect leakage detection rate.

Disclosure of Invention

The utility model aims to overcome the defects of the prior art, and designs a high-sensitivity detection probe with a magnetic shielding layer based on AC/DC composite excitation, so that the accurate identification of surface and buried defects is realized, and the defect omission rate is reduced.

The embodiment of the application provides a high-sensitivity detection probe based on an alternating current-direct current composite excitation magnetic shielding layer. The high-sensitivity detection probe based on the AC/DC composite excitation magnetic shielding layer comprises a fixing screw, a gland, a signal processing circuit, U-shaped soft iron, a large magnetic shielding layer, a small magnetic shielding layer, an AC excitation module, a DC excitation module, a TMR magnetic sensor, a soft rigid brush, a Lei Mo joint and a shell, wherein the TMR magnetic sensor is horizontally arranged at the middle position of the bottom of the shell, the AC excitation module is arranged right above the TMR magnetic sensor, the DC excitation module is arranged at the outer sides of two ends of the AC excitation module and right faces to two pins of a magnetic core of the AC excitation module, the upper end of the direct current excitation module is connected with the U-shaped soft iron, the lower end of the direct current excitation module is connected with the soft rigid brush, the lower end of the soft rigid brush is directly contacted with a tested test piece, the large magnetic shielding layer is sleeved between the direct current excitation module and the alternating current excitation module, the small magnetic shielding layer is sleeved between the alternating current excitation module and the TMR magnetic sensor, the signal processing circuit is arranged at the upper end of the U-shaped soft iron, the Lei Mo joint is arranged at one side of the shell, signals are transmitted between the detection probe and the case, and through holes are formed in four corners of the gland and fix the shell through fixing screws.

Further, the alternating current excitation module comprises an excitation coil and a U-shaped magnetic core, the excitation coil is uniformly wound on the U-shaped magnetic core, an induction magnetic field is excited by loading uniform alternating current on the excitation coil, the direct current excitation module comprises two permanent magnets, the direct current excitation induction magnetic field is generated by the permanent magnets, and the U-shaped soft iron is used as a magnetic loop for forming a space magnetic field generated by the direct current excitation module; the TMR magnetic sensor picks up distorted magnetic field signals, and the signals are amplified and filtered through the signal processing circuit.

Further, the large magnetic shielding layer is sleeved on the outer side of the alternating current excitation module, the influence of the space magnetic field generated by the direct current excitation module on the alternating current excitation module is shielded, the small magnetic shielding layer is sleeved on the outer side of the TMR magnetic sensor, the influence of the space magnetic field generated by the alternating current excitation module and the direct current excitation module on the leakage magnetic field is shielded, the lower end of the soft rigid brush is directly contacted with a tested test piece, the magnetic field generated by the direct current excitation module is guided into the tested test piece, and the strength of the leakage magnetic field is increased.

Further, the shell includes main part, TMR mounting groove, little magnetic shielding layer mounting groove, U type magnetic core mounting groove, big magnetic shielding layer mounting groove, direct current excitation module mounting groove, soft just brush mounting groove, screw hole, lei Mo joint mounting hole, the TMR mounting groove is established in shell bottom intermediate position, installs the TMR sensor, little magnetic shielding layer mounting groove equipartition is in the shell bottom the TMR mounting groove installs little magnetic shielding layer, U type magnetic core mounting groove is established in the shell bottom the both sides of mounting groove are used for the installation the U type magnetic core of alternating current excitation module, big magnetic shielding layer mounting groove is established in the shell bottom U type magnetic core mounting groove outside, direct current excitation module mounting groove is established probe length direction both ends department is used for the installation direct current excitation module and U type soft iron, soft just brush mounting groove is established direct current excitation module mounting groove directly under, be used for installing soft just brush, the screw hole with fixed screw is fixed the shell with gland, lei Mo connects the mounting hole with the joint Lei Mo.

Compared with the prior art, the beneficial technical effects of the technical scheme provided by the embodiment of the application include:

(1) The detection method is simple and does not need a coupling agent

(2) The AC/DC composite excitation signal can accurately identify surface and buried depth defects and reduce the omission ratio

(3) The design of the large magnetic shielding layer and the small magnetic shielding layer greatly reduces the mutual influence between the two excitations, so that the defect signal is more obvious

(4) Simple operation and easy operation

Drawings

In order to more clearly illustrate the embodiments of the utility model or the technical solutions of the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the utility model, and other drawings can be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is an overall schematic diagram of a high-sensitivity detection probe with a magnetic shielding layer based on AC/DC composite excitation in an embodiment of the application

FIG. 2 is a schematic diagram of an explosion structure of a high-sensitivity detection probe with a magnetic shielding layer based on AC/DC composite excitation in an embodiment of the application

FIG. 3 is an assembly schematic diagram of a high-sensitivity detection probe with a magnetic shielding layer based on AC/DC composite excitation in an embodiment of the application

FIG. 4 is a schematic view of the structure of the housing according to the embodiment of the present application

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present utility model more apparent, the technical solutions of the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model, and it is apparent that the described embodiments are some embodiments of the present utility model, but not all embodiments of the present utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

The embodiment of the application provides a high-sensitivity detection probe based on an alternating current-direct current composite excitation magnetic shielding layer. As shown in fig. 1 to 3, the high-sensitivity detection probe based on the ac-dc composite excitation magnetic shielding layer comprises a fixing screw 1, a gland 2, a signal processing circuit 3, a U-shaped soft iron 4, a large magnetic shielding layer 5, a small magnetic shielding layer 8, an ac excitation module 7, a dc excitation module 6, a TMR magnetic sensor 9, soft rigid brushes 10 and Lei Mo joints 11 and a shell 12, wherein the TMR magnetic sensor 9 is horizontally arranged at the middle position of the bottom of the shell 12, the ac excitation module 7 is arranged right above the TMR magnetic sensor 9, the dc excitation module 6 is arranged at the outer sides of two ends of the ac excitation module 7 and is opposite to two pins of the ac excitation module magnetic core 7-2, the upper end of the dc excitation module 6 is connected with the U-shaped soft iron 4, the lower end of the soft rigid brushes 10 is connected with a tested sample, the large magnetic shielding layer 5 is sleeved between the dc excitation module 6 and the ac excitation module 7, the small magnetic shielding layer 8 is sleeved between the ac excitation module 7 and the magnetic sensor 7, the small magnetic shielding layer 7 is sleeved between the ac excitation module 7 and the magnetic sensor 9, the signal processing circuit is arranged at the upper side of the four-side of the shell 2 and is fixed with the magnetic sensor 11 through the signal transmission screw Lei Mo.

Further, the ac excitation module 7 includes an excitation coil 7-1 and a U-shaped magnetic core 7-2, the excitation coil 7-1 is uniformly wound on the U-shaped magnetic core 7-2, and an induced magnetic field is excited by loading a uniform alternating current on the excitation coil 7-1, the dc excitation module 6 includes two permanent magnets, and a dc excitation induced magnetic field is generated by the permanent magnets, and the U-shaped soft iron 4 acts as a magnetic circuit that forms a space magnetic field generated by the dc excitation module 6; the TMR magnetic sensor 9 picks up the distorted magnetic field signal, and performs amplification and filtering processing by the signal processing circuit 3.

Further, the large magnetic shielding layer 5 is sleeved outside the alternating current excitation module 7, the influence of the space magnetic field generated by the direct current excitation module 6 on the alternating current excitation module 7 is shielded, the small magnetic shielding layer 8 is sleeved outside the TMR magnetic sensor 9, the influence of the space magnetic field generated by the alternating current excitation module 7 and the direct current excitation module 6 on the leakage magnetic field is shielded, the lower end of the soft rigid brush 10 is directly contacted with a tested test piece, the magnetic field generated by the direct current excitation module 6 is led into the tested test piece, and the leakage magnetic field strength is increased.

Further, the shell 12 comprises a main body 12-1, a TMR mounting groove 12-2, a small magnetic shielding layer mounting groove 12-3, a U-shaped magnetic core mounting groove 12-4, a large magnetic shielding layer mounting groove 12-5, a direct current excitation module mounting groove 12-6, a soft rigid brush mounting groove 12-7, threaded holes 12-8 and Lei Mo joint mounting holes 12-9, wherein the TMR mounting groove 12-2 is arranged at the middle position of the bottom of the shell 12 and is used for mounting the TMR sensor 9, the small magnetic shielding layer mounting groove 12-3 is uniformly distributed at the periphery of the TMR mounting groove 12-2 at the bottom of the shell 12 and is used for mounting the small magnetic shielding layer 8, the U-shaped magnetic core mounting groove 12-4 is arranged at two sides of the bottom of the shell 12-2 and is used for mounting the U-shaped magnetic core 7-2 of the alternating current excitation module 7, the large magnetic shielding layer mounting groove 12-5 is arranged at the outer side of the U-shaped magnetic core mounting groove 12-4, the direct current excitation module mounting groove 12-6 is arranged at two ends of the joint in the middle of the bottom of the shell 12 and is used for mounting the direct current excitation module mounting groove 12-6 in the length direction of the probe and is used for mounting the direct current excitation module 12 and is used for mounting the soft magnetic core 7-4 and the soft magnetic core 7-4 is used for being fixedly matched with the soft magnetic core mounting hole 35-12 and the soft magnetic core 12-9.

Claims (4)

1. A high-sensitivity detection probe based on an AC/DC composite excitation magnetic shielding layer is characterized by comprising a fixing screw, a gland, a signal processing circuit, U-shaped soft iron, a large magnetic shielding layer, a small magnetic shielding layer, an AC excitation module, a DC excitation module, a TMR magnetic sensor, a soft rigid brush, a Lei Mo joint and a shell; the alternating current excitation module comprises an excitation coil and a U-shaped magnetic core, wherein the excitation coil is uniformly wound on the U-shaped magnetic core, an induction magnetic field is excited by loading uniform alternating current on the excitation coil, the direct current excitation module comprises two permanent magnets, a direct current excitation induction magnetic field is generated by the permanent magnets, and the U-shaped soft iron acts as a magnetic loop for forming a space magnetic field generated by the direct current excitation module; the TMR magnetic sensor is horizontally arranged at the middle position of the bottom of the shell, the alternating current excitation module is arranged right above the TMR magnetic sensor, the direct current excitation module is arranged at the outer sides of two ends of the alternating current excitation module and is opposite to two pins of a magnetic core of the alternating current excitation module, the upper end of the direct current excitation module is connected with the U-shaped soft iron, the lower end of the direct current excitation module is connected with the soft rigid brush, the lower end of the soft rigid brush is directly contacted with a tested test piece, the large magnetic shielding layer is sleeved between the direct current excitation module and the alternating current excitation module, the small magnetic shielding layer is sleeved between the alternating current excitation module and the TMR magnetic sensor, the signal processing circuit is arranged at the upper end of the U-shaped soft iron, the Lei Mo joint is arranged at one side of the shell, signals are transmitted between the detection probe and the case, and through holes are formed in four corners of the gland, and the shell is fixed through fixing screws; the TMR magnetic sensor picks up distorted magnetic field signals, and the signals are amplified and filtered through the signal processing circuit.

2. The high-sensitivity detection probe based on the AC/DC composite excitation magnetic shielding layer according to claim 1, wherein two excitation modules are provided for respectively generating a DC excitation magnetic field and an AC excitation magnetic field.

3. The high-sensitivity detection probe based on the alternating current-direct current composite excitation magnetic shielding layer is characterized in that the large magnetic shielding layer is sleeved outside the alternating current excitation module, the influence of a space magnetic field generated by the direct current excitation module on the alternating current excitation module is shielded, the small magnetic shielding layer is sleeved outside the TMR magnetic sensor, the influence of the space magnetic field generated by the alternating current-direct current excitation module on a leakage magnetic field is shielded, the lower end of the soft rigid brush is directly contacted with a tested test piece, the magnetic field generated by the direct current excitation module is guided into the tested test piece, and the strength of the leakage magnetic field is increased.

4. The high-sensitivity detection probe based on an alternating current-direct current composite excitation magnetic shielding layer, as set forth in claim 1, wherein the housing comprises a main body, a TMR mounting groove, a small magnetic shielding layer mounting groove, a U-shaped magnetic core mounting groove, a large magnetic shielding layer mounting groove, a direct current excitation module mounting groove, a soft rigid brush mounting groove, a threaded hole and Lei Mo joint mounting holes, wherein the TMR mounting groove is arranged at the middle position of the bottom of the housing, the TMR magnetic sensor is mounted, the small magnetic shielding layer mounting groove is uniformly distributed at the bottom of the housing around the TMR mounting groove, the small magnetic shielding layer is mounted, the U-shaped magnetic core mounting groove is arranged at the bottom of the housing at two sides of the TMR mounting groove, for mounting the U-shaped magnetic core of the alternating current excitation module, the large magnetic shielding layer mounting groove is arranged at the outer side of the U-shaped magnetic core mounting groove, the direct current excitation module mounting groove is arranged at two ends of the length direction of the probe, for mounting permanent magnets and U-shaped soft irons of the direct current excitation module, the soft rigid brush mounting groove is arranged under the direct current excitation module mounting groove, for mounting soft brushes, the soft magnetic core mounting groove is used for mounting soft magnetic cores, the permanent magnets and the soft magnet and the soft irons, and the permanent magnet excitation module mounting screw and the permanent magnet and the soft iron joint mounting screw and the fixing joint Lei Mo.