Sensor for detecting metal motion by using magnetic field change

Abstract

The utility model discloses a sensor using magnetic field change to detect metal motion, comprising a hollow housing, the housing is provided with a detection hole, and the housing is internally provided with a first magnet, a second magnet, a Hall element, a PCB assembly board connected with the Hall element, and a power supply assembly electrically connected with the Hall element and the PCB assembly board. The upper end of the first magnet and the upper end of the second magnet are opposite in magnetism, the lower end of the first magnet and the lower end of the second magnet are opposite in magnetism, and the first magnet and the second magnet are symmetrically arranged on the left side and the right side of the Hall element. The two magnets with opposite magnetic poles are adopted, the stability of a magnetic field can be enhanced, the magnets and the Hall element are arranged in the shell, the shell can play a certain magnetic field shielding role, external magnetic field interference is reduced, and the motion detection capacity of a metal body passing through a detection hole is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of sensors, in particular to a sensor for detecting metal movement by utilizing magnetic field changes. Background Art

[0002] Metal detection sensors are basically used to determine whether there is a metal object within its detection range or to detect the movement of a metal object. However, existing metal detection sensors are easily interfered by external magnetic fields and often make misjudgments. Utility Model Content

[0003] In view of this, the purpose of the utility model is to provide a sensor for detecting metal movement by using magnetic field changes. The sensor enhances the stability of the magnetic field by attracting two magnets and shields the external magnetic field to a certain extent through the shell.

[0004] The technical solution adopted by the utility model to solve its technical problems is to provide a sensor for detecting metal movement by using magnetic field changes, including a hollow shell, the shell is provided with a detection hole, a first magnet, a second magnet, a Hall element, a PCB assembly board connected to the Hall element, and a power supply component electrically connected to the Hall element and the PCB assembly board are arranged in the shell, the upper end of the first magnet and the upper end of the second magnet have opposite magnetic properties, the lower end of the first magnet and the lower end of the second magnet have opposite magnetic properties, and the first magnet and the second magnet are symmetrically arranged on the left and right sides of the Hall element.

[0005] As a further improvement of the utility model, the first magnet is in close contact with the second magnet, and the Hall element is arranged on the surface of the first magnet and the second magnet at one end close to the detection hole.

[0006] As a further improvement of the utility model, the sensor further includes a gasket arranged between the first magnet and the Hall element to adjust the distance between the Hall element and the first magnet.

[0007] As a further improvement of the utility model, a bracket for fixing the first magnet and the second magnet is provided in the shell.

[0008] As a further improvement of the utility model, the bracket is provided with a limiting frame arranged between the first magnet and the second magnet so that there is a gap between the first magnet and the second magnet, and the Hall element is fixed on the limiting frame.

[0009] As a further improvement of the utility model, the detection hole is arranged at the upper end of the shell, and the first magnet, the second magnet and the Hall element are all located below the end of the detection hole.

[0010] As a further improvement of the utility model, the outer shell is cylindrical and has magnetism.

[0011] As a further improvement of the present invention, the PCB assembly board includes an operational amplifier connected to the Hall element, and the output end of the operational amplifier is connected to an LED lamp, a filter and a jumper interface.

[0012] The beneficial effect of the utility model is at least as follows: when a single magnet is used to detect metal movement, since there may be a large number of metal bodies or other magnetic materials in the environment, it is easy to cause changes in the magnetic field and cause detection errors. The use of two magnets with opposite poles can enhance the stability of the magnetic field, and the magnet and the Hall element are both arranged in the outer shell. The outer shell can play a certain role in shielding the magnetic field, reduce external magnetic field interference, and improve the ability to detect the movement of metal bodies passing near the detection hole. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural schematic diagram of the first embodiment of the utility model;

[0014] Figure 2 It is a schematic diagram of the circuit structure of the utility model;

[0015] Figure 3 This is a schematic diagram of the magnetic field of the first embodiment of the utility model;

[0016] Figure 4 It is a structural sectional view of the second embodiment of the utility model. DETAILED DESCRIPTION

[0017] The technical solution of the utility model will be clearly and completely described below in conjunction with the accompanying drawings.

[0018] Reference Figure 1-4The utility model proposes a sensor for detecting metal movement by using magnetic field changes, comprising a hollow shell 1, the shell 1 is provided with a detection hole 11, a first magnet 2, a second magnet 3, a Hall element 4, a PCB assembly board 5 connected to the Hall element 4, and a power supply component 6 electrically connecting the Hall element 4 and the PCB assembly board 5 are arranged in the shell 1, the upper end of the first magnet 2 and the upper end of the second magnet 3 are magnetically opposite, the lower end of the first magnet 2 and the lower end of the second magnet 3 are magnetically opposite, and the first magnet 2 and the second magnet 3 are symmetrically arranged on the left and right sides of the Hall element 4; when a metal body moves in the induction area of ​​the two magnets and the Hall element, the metal body will cut the magnetic flux lines in the magnetic field generated by the two magnets, thereby generating eddy currents in the metal body, the current generates a magnetic field, and the change of the magnetic field will be detected by the Hall element, which is manifested as a change in the output voltage value. When the metal object stops moving, the eddy current and magnetic field will disappear, and the output voltage value of the Hall element will not change. Using this principle, it is possible to detect whether the metal object is moving. When a single magnet is used to detect metal movement, since there will be a large number of metal objects or other magnetic materials in the environment, it is easy to cause changes in the magnetic field and cause detection errors. The use of two magnets with opposite poles can enhance the stability of the magnetic field, and the magnet and the Hall element are both arranged in the shell 1. The shell 1 can play a certain role in magnetic field shielding, reduce external magnetic field interference, and improve the ability to detect the movement of metal objects passing near the detection hole 11. The first magnet 2 and the second magnet 3 are symmetrically arranged on the left and right sides of the Hall element 4 so that the Hall element 4 is located in a strong magnetic position for detection, thereby improving the detection ability of the Hall element 4.

[0019] Reference Figure 3 The first magnet 2 is in close contact with the second magnet 3 , and the Hall element 4 is arranged on the surface of one end of the first magnet 2 and the second magnet 3 close to the detection hole 11 .

[0020] Reference Figure 3 The sensor also includes a gasket arranged between the first magnet 2 and the Hall element 4 to adjust the distance between the Hall element 4 and the first magnet 2; since the Hall element 4 has a range for detecting the magnetic field, once the magnetic field formed by the two magnets exceeds the detection range of the Hall element 4, the distance between the Hall element 4 and the magnet can be appropriately increased to keep the magnetic flux within the detection range of the Hall element. When detecting a metal body, the magnetic field generated by the metal body conflicts with the original magnetic field. Therefore, as long as the magnetic flux of the original magnetic field is kept within the detection range of the Hall element, the magnetic field changes generated by the metal body can always be detected.

[0021] As a further improvement of the present invention, a bracket 12 for fixing the first magnet 2 and the second magnet 3 is provided in the housing 1 .

[0022] Reference Figure 4The bracket 12 is provided with a limiting frame 121 arranged between the first magnet 2 and the second magnet 3 so that there is a gap between the first magnet 2 and the second magnet 3, and the Hall element 4 is fixed on the limiting frame 121; due to the attraction between opposite poles, the two magnets have a magnetic force that attracts each other, so the two magnets are separated by the setting of the limiting frame 121, providing conditions for installing the Hall element 4.

[0023] Reference Figure 4 The detection hole 11 is arranged at the upper end of the housing 1, and the first magnet 2, the second magnet 3 and the Hall element 4 are all located below the end of the detection hole 11. The metal body can be detected by a mobile sensor, or it can be installed on a production line to detect material loading. The first magnet 2, the second magnet 3 and the Hall element 4 are all located below the end of the detection hole 11 to avoid scratches and damage to the Hall element 4.

[0024] As a further improvement of the present invention, the shell 1 is cylindrical and has magnetism; the two magnets in opposite directions interact with each other to form a relatively concentrated and directional magnetic field area at the port of the detection hole 11, which plays a role in focusing the magnetic field.

[0025] As a further improvement of the present invention, the PCB assembly board 5 includes an operational amplifier connected to the Hall element 4, and the output end of the operational amplifier is connected to an LED light for reminding the movement of the metal body, a filter for reducing electromagnetic interference, and a jumper interface.

Claims

1. A sensor for detecting metal movement using magnetic field changes, characterized in that: The invention comprises a hollow shell (1), wherein the shell (1) is provided with a detection hole (11), wherein a first magnet (2), a second magnet (3), a Hall element (4), a PCB assembly board (5) connected to the Hall element (4), and a power supply component (6) electrically connected to the Hall element (4) and the PCB assembly board (5) are arranged inside the shell (1), wherein the upper end of the first magnet (2) and the upper end of the second magnet (3) have opposite magnetic properties, the lower end of the first magnet (2) and the lower end of the second magnet (3) have opposite magnetic properties, and the first magnet (2) and the second magnet (3) are symmetrically arranged on the left and right sides of the Hall element (4).

2. A sensor for detecting metal movement using magnetic field changes according to claim 1, characterized in that: The first magnet (2) is in close contact with the second magnet (3), and the Hall element (4) is arranged on the surface of one end of the first magnet (2) and the second magnet (3) close to the detection hole (11).

3. A sensor for detecting metal movement using magnetic field changes according to claim 2, characterized in that: The sensor further comprises a spacer arranged between the first magnet (2) and the Hall element (4) to adjust the distance between the Hall element (4) and the first magnet (2).

4. A sensor for detecting metal movement using magnetic field changes according to claim 1, characterized in that: A bracket (12) for fixing the first magnet (2) and the second magnet (3) is provided in the housing (1).

5. A sensor for detecting metal movement using magnetic field changes according to claim 4, characterized in that: The bracket (12) is provided with a limiting frame (121) arranged between the first magnet (2) and the second magnet (3) so that there is a gap between the first magnet (2) and the second magnet (3), and the Hall element (4) is fixed on the limiting frame (121).

6. A sensor for detecting metal movement using magnetic field changes according to claim 5, characterized in that: The detection hole (11) is arranged at the upper end of the housing (1), and the first magnet (2), the second magnet (3) and the Hall element (4) are all located below the end of the detection hole (11).

7. A sensor for detecting metal movement using magnetic field changes according to claim 1, characterized in that: The shell (1) is cylindrical and has magnetism.

8. The sensor for detecting metal movement by using magnetic field changes according to claim 1, characterized in that: The PCB assembly board (5) comprises an operational amplifier connected to the Hall element (4), and the output end of the operational amplifier is connected to an LED lamp, a filter and a jumper interface.

Images