A device and method for rapidly measuring the surface resistance of a magnetic core

Abstract

The present application belongs to the technical field of magnetic core performance detection, and particularly relates to a rapid measuring device and method for surface resistance of a magnetic core, comprising a multimeter, a test seat and a magnetic core to be measured; the test seat comprises a bottom shell, an electrode fixing seat, a first electrode and a second electrode, the electrode fixing seat is fixedly installed on the bottom shell, and the first electrode and the second electrode are symmetrically arranged on the electrode fixing seat and have the same structure; the first electrode is electrically connected to the positive pole of the multimeter resistance block through a red wire, the second electrode is electrically connected to the negative pole of the multimeter resistance block through a black wire, the connection ends of the red wire and the black wire with the multimeter are all provided with banana plugs, and when the magnetic core to be measured is arranged between the first electrode and the second electrode, a closed electric circuit is formed, and the present application has the beneficial effects that the problems of unstable electrode spacing and unstable contact pressure in the traditional manual probe measurement are solved, batch and standardized measurement of the surface resistance of the magnetic core is realized, and the present application is suitable for rapid sampling inspection and quality determination of the magnetic core.

Description

Technical Field

[0001] This invention relates to the field of magnetic core performance testing technology, specifically to a rapid measurement device and method for the surface resistance of magnetic cores. Background Technology

[0002] As a core component in electronic devices, the surface resistance of magnetic cores directly reflects key indicators such as surface insulation performance, surface damage, and coating integrity. It is a crucial parameter for core manufacturing, incoming material inspection, and quality control. Currently, the surface resistance of magnetic cores is mostly tested manually using a handheld multimeter probe. This method has several drawbacks: manual probe operation makes it difficult to ensure a constant electrode spacing, and the path length of current flow varies with different test cycles, leading to significant measurement deviations; furthermore, the contact pressure between the probe and the core surface is entirely dependent on manual control, and poor contact or excessive pressure can affect the accuracy of the resistance value. Summary of the Invention

[0003] The present invention addresses the problems mentioned above by designing a rapid measurement device and method for the surface resistance of magnetic cores, thereby overcoming the deficiencies of the prior art.

[0004] To achieve the above objectives, the present invention provides a rapid measurement device for the surface resistance of a magnetic core, comprising a multimeter, a test socket, and a magnetic core to be tested. The test socket includes a base, an electrode holder, a first electrode, and a second electrode. The electrode holder is fixedly mounted on the base. The first electrode and the second electrode have the same structure and are symmetrically arranged on the electrode holder. The first electrode is electrically connected to the positive terminal of the multimeter's resistance range via a red wire, and the second electrode is electrically connected to the negative terminal of the multimeter's resistance range via a black wire. The connection terminals of the red wire, the black wire, and the multimeter are all banana plugs. When the magnetic core to be tested is placed between the first electrode and the second electrode, a closed electrical circuit is formed.

[0005] Furthermore, both the first electrode and the second electrode include a first bending plate, a second bending plate, and a contact plate formed by bending in the same way. The first bending plate includes a horizontal plate surface and a vertical plate surface with a 90° bending angle. The horizontal plate surface is detachably fixed to the electrode fixing seat by fastening bolts. One end of the second bending plate is fixedly connected to the vertical plate surface, and the other end is fixedly connected to the contact plate.

[0006] Furthermore, the second bending plate and the contact plate enclose a receiving space, which is used to accommodate the wiring terminals that connect the red wire, the black wire and the corresponding electrode.

[0007] Furthermore, the bottom shell has a hollow structure, and the side wall of the bottom shell has a wire outlet hole. Parts of the red wire and the black wire are housed in the hollow structure of the bottom shell, and the remaining parts are led out through the wire outlet hole.

[0008] Furthermore, a first insulating wiring groove and a second insulating wiring groove are respectively laid in the cavity structure of the bottom shell. A red wire is inserted in the first insulating wiring groove and a black wire is inserted in the second insulating wiring groove.

[0009] Furthermore, both the first and second insulating wiring channels include a first wiring plate and a second wiring plate, which are elongated strips. The first wiring plate is fixedly connected to a support plate, and the second wiring plate is hinged to a baffle.

[0010] Furthermore, a winding wheel is rotatably mounted on the support plate via a rotating shaft, and a rubber pad is fixedly connected to the baffle at the position corresponding to the rotating shaft. One end of the rotating shaft is rotatably connected to the support plate via a bearing, and the other end abuts against the rubber pad. The second cable tray is also hinged with an elastic metal pressure plate, which abuts against and fixes the baffle after rotating.

[0011] This invention also includes a method for measuring the surface resistance of a magnetic core using a rapid measuring device, comprising the following steps: Step 1: Wiring preparation: Connect the first and second electrodes of the test socket to the positive and negative terminals of the multimeter's resistance setting, respectively. Turn on the multimeter and adjust it to the appropriate resistance setting. Step 2: The magnetic core to be tested is placed smoothly between the first and second electrodes of the test holder. Under the action of the elastic pressure component, the electrodes and the surface of the magnetic core are in close contact, forming a closed circuit. Step 3: Resistance Measurement: Apply a constant test voltage with a multimeter, detect the circuit current, and calculate the surface resistance value of the magnetic core under test between the two electrodes according to Ohm's law R=U / I, and display it directly on the screen; Step 4: Result Determination: Based on the displayed surface resistance value, determine whether there is damage or insulation failure on the surface of the magnetic core, and complete the measurement.

[0012] Furthermore, in step one, the first electrode is connected to the positive terminal of the multimeter via a red wire, and the second electrode is connected to the negative terminal of the multimeter via a black wire. The winding process of the red and black wires is as follows: the terminals at one end are respectively embedded in the receiving spaces of the first and second electrodes and fixedly connected to the corresponding electrodes; the other ends are respectively inserted between the first and second wire routing plates of the corresponding insulating wire routing grooves, and then sequentially wound onto the winding wheel of the support plate; before winding begins, the baffle is flipped by the hinge to keep the baffle in the open state to avoid obstructing the winding operation; after winding is completed, the baffle is lowered so that the rubber pad is tightly abutted against the other end of the shaft of the winding wheel, forming a damping limit on the shaft; then the elastic metal pressure plate hinged on the second wire routing plate is rotated so that the elastic metal pressure plate abuts against and presses the baffle, thereby fixing the baffle and completing the winding and fixing of the wire.

[0013] Furthermore, when it is necessary to release the wire, rotate the elastic metal pressure plate in the opposite direction to release the pressure on the baffle, then flip the baffle to open it, release the rubber pad from the abutment limit of the rotating shaft, and rotate the winding wheel to release the wire.

[0014] In summary, the present invention has the following advantages and beneficial technical effects: 1. This invention relies on a commercially available multimeter, requiring only a simple fixture and eliminating the need for a dedicated resistance tester or complex equipment, thus lowering the barrier to entry and procurement costs. The test socket designed in this invention achieves a fixed electrode spacing, and the electrodes utilize large-area sheet-like contacts instead of probes, resulting in more stable contact, avoiding point contact errors, and structurally eliminating variables caused by manual operation.

[0015] 2. This invention measures surface resistance with fixed parameters and directly determines whether the magnetic core is damaged through numerical thresholds. It eliminates the need for complex multi-directional and multi-angle tests, focusing on the need for rapid screening in the production site and achieving rapid quality screening.

[0016] 3. The bottom shell of this invention is designed as a cavity structure and equipped with components such as an insulated wiring trough and a winding wheel, which can orderly store and fix the red and black wires, and realize free adjustment of wire winding and unwinding, avoiding messy tangling, wear and breakage of wires; at the same time, the wiring terminals of the wires and electrodes are housed in the dedicated housing space of the electrodes, and the insulated wiring trough protects the wires, effectively reducing the damage to the wires caused by external pulling and environmental friction, extending the service life of the device, and the neat wiring makes the device more convenient to carry, store and use on site.

[0017] 4. The first electrode and the second electrode of this invention are detachably fixed to the electrode mounting base by fastening bolts. When the electrode is worn or deformed, the electrode can be replaced individually without replacing the entire test base, thus reducing the maintenance cost of the device. At the same time, the appropriate electrode can be replaced or the electrode fixing distance can be adjusted according to the testing requirements of different specifications of magnetic cores. Attached Figure Description

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of the internal structure of the bottom shell in this invention; Figure 3 This is a three-dimensional schematic diagram of the insulating wiring groove in this invention; Figure 4 This is a side view of the insulated wiring trough in this invention.

[0019] The reference numerals in the attached figures are: 1. Multimeter; 2. Test socket; 21. Base shell; 22. Electrode holder; 23. First electrode; 24. Second electrode; 25. Outlet hole; 3. Magnetic core under test; 4. Red wire; 5. Black wire; 6. Wiring board one; 7. Wiring board two; 8. Support plate; 9. Baffle; 10. Winding wheel; 11. Elastic metal pressure plate. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout; the described embodiments are some embodiments of this invention, but not all embodiments; the embodiments and directional terms described below with reference to the accompanying drawings are exemplary and intended to explain this invention, and should not be construed as limiting this invention; all other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention. The embodiments of this invention will be described in detail below with reference to the accompanying drawings: The following is in conjunction with the appendix Figures 1-4 The present invention will be further described in detail below: Example 1 like Figure 1As shown, this embodiment discloses a rapid measurement device for the surface resistance of a magnetic core, including a multimeter 1, a test base 2, and a magnetic core 3 to be tested. The test base 2 includes a base 21, an electrode holder 22, a first electrode 23, and a second electrode 24. The electrode holder 22 is fixedly mounted on the base 21. The first electrode 23 and the second electrode 24 have the same structure and are symmetrically arranged on the electrode holder 22, with a fixed distance between them to form a standard measurement distance. The first electrode 23 is electrically connected to the positive terminal of the resistance range of the multimeter 1 through a red wire 4, and the second electrode 24 is electrically connected to the negative terminal of the resistance range of the multimeter 1 through a black wire 5. The connection terminals of the red wire 4, the black wire 5, and the multimeter 1 are all banana plugs. When the magnetic core 3 to be tested is placed between the first electrode 23 and the second electrode 24, a closed electrical circuit is formed. Both the first electrode 23 and the second electrode 24 are integral metal spring structures, each including a first bent plate, a second bent plate, and a contact plate formed by bending them. The first bent plate includes a horizontal plate surface and a vertical plate surface with a 90° bending angle. The horizontal plate surface is detachably fixed to the electrode fixing base 22 by fastening bolts. One end of the second bent plate is fixedly connected to the vertical plate surface, and the other end is fixedly connected to the contact plate. The second bent plate and the contact plate enclose a receiving space for accommodating the terminals of the red wire 4 and the black wire 5 connected to the corresponding electrodes.

[0021] like Figures 2-4 As shown, the bottom shell 21 has a hollow structure, and a wire outlet hole 25 is provided on the side wall of the bottom shell 21. Partial sections of the red wire 4 and the black wire 5 are housed in the hollow structure of the bottom shell 21, while the remaining sections are led out through the wire outlet hole 25. A first insulating wire routing groove and a second insulating wire routing groove are respectively laid in the hollow structure of the bottom shell 21. The red wire 4 is inserted in the first insulating wire routing groove, and the black wire 5 is inserted in the second insulating wire routing groove. Both the first insulating wire routing groove and the second insulating wire routing groove include a long strip-shaped wire routing plate 6 and a wire routing plate 7. The wire routing plate 6 is fixedly connected to a semi-circular support plate 8, and the wire routing plate 7 is hinged to a long strip-shaped baffle 9. A winding wheel 10 is rotatably mounted on the support plate 8 via a rotating shaft. A rubber pad is fixedly connected to the baffle 9 at the position corresponding to the rotating shaft. One end of the rotating shaft is rotatably connected to the support plate 8 via a bearing, and the other end abuts against the rubber pad. The cable tray 7 is also hinged with an elastic metal pressure plate 11. After the elastic metal pressure plate 11 rotates, it abuts against and fixes the baffle 9.

[0022] Example 2 The measurement method of the rapid measurement device for the surface resistance of a magnetic core according to the present invention is as follows: Step 1, Wiring Preparation: Connect the first electrode 23 of the test socket 2 to the positive terminal of the multimeter 1 resistance range via the red wire 4, and connect the second electrode 24 to the negative terminal of the multimeter 1 resistance range via the black wire 5. Turn on the multimeter 1 and adjust it to the appropriate resistance range.

[0023] The winding process of red wire 4 and black wire 5 is as follows: the terminals at one end are respectively embedded in the receiving spaces of the first electrode 23 and the second electrode 24, and are fixedly connected to the corresponding electrodes; the other end is respectively inserted between the first wire routing plate 6 and the second wire routing plate 7 of the corresponding insulating wire routing groove, and then sequentially wound onto the winding wheel 10 of the support plate 8; before winding begins, the baffle 9 is flipped by the hinge to keep the baffle 9 in the open state to avoid obstructing the winding operation; after winding is completed, the baffle 9 is lowered so that the rubber pad is tightly abutted against the other end of the shaft of the winding wheel 10, forming a damping limit on the shaft, and then the elastic metal pressure plate 11 hinged on the second wire routing plate 7 is rotated so that the elastic metal pressure plate 11 abuts against and presses the baffle 9, thereby fixing the baffle 9 and completing the winding and fixing of the wire.

[0024] When it is necessary to release the wire, rotate the elastic metal pressure plate 11 in the opposite direction to release the pressure on the baffle 9, then flip the baffle 9 to open it, release the rubber pad from the abutment limit of the rotating shaft, and rotate the winding wheel 10 to release the wire.

[0025] Step 2: The magnetic core 3 to be tested is placed smoothly between the contact plates of the first electrode 23 and the second electrode 24 of the test holder 2. Under the action of the elastic pressure component, the electrode and the surface of the magnetic core are in close contact, forming a closed circuit.

[0026] Step 3, Resistance Measurement: Apply a constant test voltage to multimeter 1, detect the circuit current, and calculate the surface resistance value of the magnetic core 3 between the two electrodes according to Ohm's law R=U / I, and display it directly on the screen.

[0027] Step 4: Result Determination: Based on the displayed surface resistance value, determine whether there is damage or insulation failure on the surface of the magnetic core, and complete the measurement.

[0028] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A rapid measurement device for the surface resistance of a magnetic core, characterized in that: The device includes a multimeter, a test socket, and a magnetic core under test. The test socket includes a base, an electrode holder, a first electrode, and a second electrode. The electrode holder is fixedly mounted on the base. The first electrode and the second electrode have the same structure and are symmetrically arranged on the electrode holder. The first electrode is electrically connected to the positive terminal of the multimeter's resistance range via a red wire, and the second electrode is electrically connected to the negative terminal of the multimeter's resistance range via a black wire. The connection terminals of the red wire, the black wire, and the multimeter are all banana plugs. When the magnetic core under test is placed between the first electrode and the second electrode, a closed electrical circuit is formed.

2. The rapid measurement device for the surface resistance of a magnetic core according to claim 1, characterized in that: The first electrode and the second electrode each include a first bent plate, a second bent plate and a contact plate formed by bending in the same way. The first bent plate includes a horizontal plate surface and a vertical plate surface with a 90° bending angle. The horizontal plate surface is detachably fixed to the electrode fixing seat by fastening bolts. One end of the second bent plate is fixedly connected to the vertical plate surface and the other end is fixedly connected to the contact plate.

3. The rapid measurement device for the surface resistance of a magnetic core according to claim 2, characterized in that: The second bending plate and the contact plate enclose a receiving space, which is used to accommodate the red wire, the black wire and the terminal block connected to the corresponding electrode.

4. The rapid measurement device for the surface resistance of a magnetic core according to claim 1, characterized in that: The bottom shell has a hollow structure, and the side wall of the bottom shell has a wire outlet hole. Parts of the red wire and black wire are housed in the hollow structure of the bottom shell, and the remaining parts are led out through the wire outlet hole.

5. The rapid measurement device for the surface resistance of a magnetic core according to claim 1, characterized in that: The cavity structure of the bottom shell is provided with a first insulating wiring groove and a second insulating wiring groove. A red wire is inserted in the first insulating wiring groove and a black wire is inserted in the second insulating wiring groove.

6. The rapid measurement device for the surface resistance of a magnetic core according to claim 5, characterized in that: Both the first and second insulating wiring troughs include a first wiring plate and a second wiring plate, which are elongated strips. The first wiring plate is fixedly connected to a support plate, and the second wiring plate is fitted with a baffle via a hinge.

7. The rapid measurement device for the surface resistance of a magnetic core according to claim 6, characterized in that: A winding wheel is rotatably mounted on the support plate via a rotating shaft. A rubber pad is fixedly connected to the baffle at the position corresponding to the rotating shaft. One end of the rotating shaft is rotatably connected to the support plate via a bearing, and the other end abuts against the rubber pad. The second cable tray is also hinged with an elastic metal pressure plate, which abuts against and fixes the baffle after rotating.

8. A method for measuring the surface resistance of a magnetic core using a rapid measuring device, characterized in that: The measurement method of the rapid measurement device for the surface resistance of a magnetic core as described in claim 1 includes the following steps: Step 1: Wiring preparation: Connect the first and second electrodes of the test socket to the positive and negative terminals of the multimeter's resistance setting, respectively. Turn on the multimeter and adjust it to the appropriate resistance setting. Step 2: The magnetic core to be tested is placed smoothly between the first and second electrodes of the test holder. Under the action of the elastic pressure component, the electrodes and the surface of the magnetic core are in close contact, forming a closed circuit. Step 3: Resistance Measurement: Apply a constant test voltage with a multimeter, detect the circuit current, and calculate the surface resistance value of the magnetic core under test between the two electrodes according to Ohm's law R=U / I, and display it directly on the screen; Step 4: Result Determination: Based on the displayed surface resistance value, determine whether there is damage or insulation failure on the surface of the magnetic core, and complete the measurement.

9. The measurement method of the rapid measurement device for the surface resistance of a magnetic core according to claim 8, characterized in that: In step one, the first electrode is connected to the positive terminal of the multimeter via a red wire, and the second electrode is connected to the negative terminal of the multimeter via a black wire. The winding process of the red and black wires is as follows: the terminals at one end are respectively embedded in the receiving spaces of the first and second electrodes and fixedly connected to the corresponding electrodes; the other ends are respectively inserted between the first and second wire routing plates of the corresponding insulating wire routing grooves, and then sequentially wound onto the winding wheel of the support plate; before winding begins, the baffle is flipped by the hinge to keep the baffle in the open state to avoid obstructing the winding operation; after winding is completed, the baffle is lowered so that the rubber pad is tightly abutted against the other end of the shaft of the winding wheel, forming a damping limit on the shaft; then the elastic metal pressure plate hinged on the second wire routing plate is rotated so that the elastic metal pressure plate abuts against and presses the baffle, thereby fixing the baffle and completing the winding and fixing of the wire.

10. The measurement method of the rapid measurement device for the surface resistance of a magnetic core according to claim 9, characterized in that: When it is time to release the wire, rotate the elastic metal pressure plate in the opposite direction to release the pressure on the baffle. Then flip the baffle to open it, release the rubber pad from the abutment of the rotating shaft, and rotate the winding wheel to release the wire.

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