Novel metal detection antenna

Abstract

The utility model relates to the field of metal detection, and discloses a novel metal detection antenna, which comprises a shell, a reserved cavity a is formed in the center of the surface of the shell, reserved cavities b are formed in the surfaces of the two sides of the shell, receiving antennas are arranged on the two sides of the inner wall of the shell, a plurality of groups of transmitting antennas are arranged on the inner cambered surface of the inner wall of the shell, and the receiving antennas and the transmitting antennas are arranged on the inner cambered surface of the inner wall of the shell. The surface of the upper end of the inner wall of the shell is provided with a transmitting coil connecting wire, the surface of the upper end of the inner wall of the shell is fixedly connected with an antenna matching circuit and a comparator, the surface of the upper end of the inner wall of the shell is provided with a plurality of groups of power strips, and the surface of the receiving antenna is wound with a plurality of groups of receiving coil shielding wires. According to the utility model, the shielding device is added in the antenna structure, the electromagnetic induction directions of different arms of the receiving antenna are opposite, the receiving antenna is combined with the operational amplifier comparator for shielding, and meanwhile, the receiving coil shielding wire is added outside the receiving antenna, so that an effective electromagnetic shielding layer is formed.

Description

Technical Field

[0001] The utility model relates to the field of metal detection, in particular to a novel metal detection antenna. Background Art

[0002] The metal detection antenna is an important part of the metal detector. The metal detector is mainly used to detect metal objects. It is generally composed of a high-frequency oscillator, an oscillation detector, an audio oscillator, a power amplifier and an antenna. The function of the antenna is to transmit and receive electromagnetic waves and interact with the metal object being detected. When the metal detector antenna emits electromagnetic waves, it will induce eddy currents inside the metal after encountering a metal object, and the eddy currents will generate a magnetic field, thereby affecting the original magnetic field. After the antenna receives this changing magnetic field, it transmits the signal to other parts of the detector for processing and analysis, and finally realizes the detection of metal objects.

[0003] Existing metal detection antennas have some shortcomings: on the one hand, due to various electromagnetic interferences in the environment (for example, from power lines, radio equipment, etc.), existing antennas are easily affected by noise, resulting in unstable detection signals, thereby affecting the accuracy of detection results; on the other hand, the designs of many existing antennas fail to effectively optimize the use of electrical energy, resulting in high power consumption of the detectors, requiring frequent replacement or charging of batteries, reducing the efficiency of use; and after receiving the signal, the existing antennas have limited ability to process and analyze the signal, making it difficult to effectively distinguish between the target object and the background noise, resulting in a high false alarm rate. Therefore, a new type of metal detection antenna is proposed to solve the above problems. Utility Model Content

[0004] In order to make up for the above deficiencies, the utility model provides a novel metal detection antenna, which aims to improve the problem in the prior art that the antenna is easily affected by noise, resulting in unstable detection signals, thereby affecting the accuracy of the detection results.

[0005] In order to achieve the above-mentioned purpose, the utility model adopts the following technical scheme: a new type of metal detection antenna, including a shell, a reserved cavity a is opened at the center of the shell surface, reserved cavities b are opened on the surfaces of both sides of the shell, receiving antennas are arranged on both sides of the inner wall of the shell, and multiple groups of transmitting antennas are arranged on the inner arc surface of the inner wall of the shell, a transmitting coil connecting wire is arranged on the surface of the upper end of the inner wall of the shell, a receiving coil same-layer connecting wire is fixedly connected to the surface of the upper end of the inner wall of the shell, an antenna matching circuit and a comparator are fixedly connected to the surface of the upper end of the inner wall of the shell, multiple groups of socket strips are arranged on the surface of the upper end of the inner wall of the shell, and multiple groups of receiving coil shielding wires are wound around the surface of the receiving antenna.

[0006] As a further description of the above technical solution:

[0007] Two groups of transmitting coil connecting wires are provided, and the bottom ends of the two groups of transmitting coil connecting wires are electrically connected to the two sides of the socket strip.

[0008] As a further description of the above technical solution:

[0009] Both sides of the same-layer connection line of the receiving coil are electrically connected to the inner side of the top of the receiving antenna.

[0010] As a further description of the above technical solution:

[0011] The antenna matching circuit and the lower surface of the comparator are electrically connected to the socket.

[0012] As a further description of the above technical solution:

[0013] The receiving coil shielding wire is fixedly connected to the surface of the inner wall of the shell.

[0014] As a further description of the above technical solution:

[0015] A trapezoidal piece is arranged at the top end of the outer arc surface of the transmitting antenna, and the upper end surface of the transmitting coil connecting wire is electrically connected to the position of the trapezoidal piece on the outer arc surface of the transmitting antenna.

[0016] The utility model has the following beneficial effects:

[0017] 1. In the utility model, a dual coil design is adopted, which is used for transmitting and receiving signals respectively. By optimizing the shape and material of the coil, the sensitivity of the antenna is significantly improved, and a shielding device is added to the antenna structure, including the electromagnetic induction directions between different arms of the receiving antenna (the antenna is an 8-layer structure, the 3rd and 4th layers are one arm of the receiving antenna, and the 5th and 6th layers are one arm of the receiving antenna) are opposite, combined with an op amp comparator for shielding, and a receiving coil shielding wire is added outside the receiving antenna to form an effective electromagnetic shielding layer. It can significantly reduce the impact of external electromagnetic interference on the detection signal and ensure the stability and reliability of signal transmission.

[0018] 2. In the present invention, the power consumption of the antenna is reduced by optimizing the circuit design and material selection, which enables the detector to save electric energy more effectively when used for a long time, prolong the service life of the battery, and reduce the frequency of replacement or charging.

[0019] 3. In this utility model, a high-precision amplifier and filter are integrated to enhance the processing capability after signal reception. The optimized signal processing system can more accurately distinguish the target object from the background noise, reduce the false alarm rate, and improve the accuracy of the sensing results.

[0020] 4. In the utility model, the shielding device not only effectively prevents external electromagnetic interference, but also has multiple through holes to avoid overheating caused by long-term use, ensuring the stable operation of the antenna in various environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the overall three-dimensional structure of a new type of metal detection antenna proposed by the utility model;

[0022] Figure 2 This is a schematic diagram of the cross-sectional structure of the internal structure of a novel metal detection antenna proposed by the utility model;

[0023] Figure 3 This is a schematic diagram of the overall local enlarged structure of a new type of metal detection antenna proposed by the utility model.

[0024] Legend:

[0025] 1. Shell; 2. Reserved cavity a; 3. Reserved cavity b; 4. Receiving antenna; 5. Transmitting antenna; 6. Transmitting coil connecting wire; 7. Receiving coil shielding wire; 8. Receiving coil same-layer connecting wire; 9. Antenna matching circuit and comparator; 10. Socket strip. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0027] Reference Figure 1-Figure 3The utility model provides an embodiment: a novel metal detection antenna, including a shell 1, the main antenna of the shell 1 adopts PCB design, the dielectric constant is 4.4-4.8. The thickness is 1.9 mm, and an eight-layer board design is adopted. A reserved cavity a2 is opened at the center of the surface of the shell 1, and a reserved cavity b3 is opened on the surface of both sides of the shell 1. Receiving antennas 4 are arranged on both sides of the inner wall of the shell 1. The receiving antenna 4 is located on the third and fourth layers of the eight-layer board, which is a group of electromagnetic induction reverse arms, and the fifth and sixth layers are the receiving antennas 4. Another group of arms with the same electromagnetic induction reverse direction are opposite to the third and fourth layers. The receiving antenna 4 consists of two groups of crescent-shaped antennas symmetrical about the left and right sides of each layer. They are connected in series through routing and wound using PCB routing. The two groups of crescent-shaped antennas on the same layer are connected in series, and the electromagnetic induction directions are consistent. The entire receiving antenna 4 has four layers, with three layers and four layers every two layers. The fifth and sixth layers serve as an arm of the receiving antenna, and the electromagnetic induction directions are in the same direction, but the electromagnetic induction directions between every two layers, three layers, four layers, and the fifth and sixth layers are opposite. With the help of operational amplifiers, internal cancellation is achieved to avoid the influence of the transmitted signal.

[0028] Reference Figure 2-Figure 3 The inner arc surface of the inner wall of the shell 1 is provided with multiple groups of transmitting antennas 5. The transmitting antenna 5 is an eight-layer coil wound clockwise, which is wound by PCB routing and has high conductivity and low resistance characteristics. The winding of the transmitting antenna 5 is provided inside the eight-layer board of the shell 1. The top of the outer arc surface of the transmitting antenna 5 is provided with a trapezoidal sheet. The upper end surface of the transmitting coil connecting wire 6 is electrically connected to the position of the trapezoidal sheet on the outer arc surface of the transmitting antenna 5. The surface of the upper end of the inner wall of the shell 1 is provided with a transmitting coil connecting wire 6. The position of the transmitting coil connecting wire 6 is set at one of the eight-layer boards of the shell 1. The transmitting coil connecting wires 6 are provided with two groups, and the bottom ends of the two groups of transmitting coil connecting wires 6 are electrically connected to the two sides of the socket strip 10. The surface of the upper end of the inner wall of the shell 1 is fixedly connected with the receiving coil same-layer connecting wires 8. The receiving coil same-layer connecting wires 8 are located on the second and seventh layers of the eight-layer board. The two sides of the receiving coil same-layer connecting wires 8 are electrically connected to the inner side of the top of the receiving antenna 4. The receiving coil same-layer connecting wires 8 are connected to the receiving antenna 4 on the same layer, and the magnetic induction directions of the two coils must be consistent; at the same time, they are also connected to the receiving antenna 4 on different layers.

[0029] Reference Figure 2-Figure 3.An antenna matching circuit and a comparator 9 are fixedly connected to the surface of the upper end of the inner wall of the shell 1. The antenna matching circuit and the comparator 9 are primary processing of the signal received by the receiving antenna 4, including circuit matching and operational amplifier comparator, which can improve the quality of the received signal and reduce interference. The antenna matching circuit and the comparator 9 are also arranged on the first layer of the eight-layer board. The lower surface of the antenna matching circuit and the comparator 9 is electrically connected to the socket 10. A plurality of groups of sockets 10 are arranged on the surface of the upper end of the inner wall of the shell 1. The socket 10 is used to connect the antenna and the rear-end signal processing part. The through holes of the socket 10 are arranged inside the eight-layer board of the shell 1, and the eighth layer of the eight-layer board of the shell 1 is only the through hole of the transmitting antenna 5 and the socket 10. A plurality of groups of receiving coil shielding wires 7 are wound around the surface of the receiving antenna 4. The receiving coil shielding wire 7 is a grounding wire perpendicular to the winding direction of the receiving antenna 4 to reduce transmission and external electromagnetic interference. The receiving coil shielding wire 7 is fixedly connected to the surface of the inner wall of the shell 1.

[0030] Working principle: respectively obtain the environmental noise data when no detected object passes through the metal detector and the actual detection data when the detected object passes through the metal detector; use the environmental noise data to calibrate the actual detection data and obtain the calibration data; according to the left and right movement of the shell 1 above the object to be detected, the different induced potentials received by the left and right coils on the receiving antenna 4 are used to determine whether there is a metal object, and at the same time, it can be determined whether it is a black metal (such as iron) or a white metal (such as aluminum, magnesium, etc.) by detecting the potential phase.

[0031] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A novel metal detection antenna, comprising a housing (1), characterized in that: A reserved cavity a (2) is provided at the center of the surface of the shell (1), and reserved cavities b (3) are provided on the surfaces of both sides of the shell (1). Receiving antennas (4) are arranged on both sides of the inner wall of the shell (1), and the inner arc surface of the inner wall of the shell (1) is provided with multiple groups of transmitting antennas (5). The surface of the upper end of the inner wall of the shell (1) is provided with a transmitting coil connecting wire (6), and the surface of the upper end of the inner wall of the shell (1) is fixedly connected to a receiving coil same-layer connecting wire (8). The surface of the upper end of the inner wall of the shell (1) is fixedly connected to an antenna matching circuit and a comparator (9). The surface of the upper end of the inner wall of the shell (1) is provided with multiple groups of plug strips (10), and the surface of the receiving antenna (4) is wound with multiple groups of receiving coil shielding wires (7).

2. A novel metal detection antenna according to claim 1, characterized in that: Two groups of transmitting coil connecting wires (6) are provided, and the bottom ends of the two groups of transmitting coil connecting wires (6) are electrically connected to two sides of the socket strip (10).

3. The novel metal detection antenna according to claim 1 is characterized in that: Both sides of the same-layer connection line (8) of the receiving coil are electrically connected to the inner side of the top end of the receiving antenna (4).

4. The novel metal detection antenna according to claim 1 is characterized in that: The antenna matching circuit and the lower surface of the comparator (9) are electrically connected to the socket (10).

5. The novel metal detection antenna according to claim 1 is characterized in that: The receiving coil shielding wire (7) is fixedly connected to the surface of the inner wall of the housing (1).

6. The novel metal detection antenna according to claim 1 is characterized in that: A trapezoidal piece is provided at the top end of the outer arc surface of the transmitting antenna (5), and the upper end surface of the transmitting coil connecting wire (6) is electrically connected to the position of the trapezoidal piece on the outer arc surface of the transmitting antenna (5).

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