VEHICLE ANTENNA FOR MAGNETIC STOP SYSTEM

Abstract

The present invention relates to the technical field of railway transport, in particular to a vehicle antenna for a magnetic stopping system. The present invention includes: a plurality of iron cores, wherein an air gap is formed between the iron cores, the lower surfaces of the iron cores are flat, and the iron cores are designed with specially shaped structures whose magnetically conductive cross-sections gradually decrease from the lower surfaces to the air gap, such that the magnetically conductive cross-sections of the iron cores reach a minimum at the air gap where the two iron cores are in contact with each other, in order to increase the magnetic flux density;A Hall sensor is provided in the air gap, and the Hall sensor is configured to detect a magnetic signal transmitted by the iron cores; the Hall sensor is connected to a detection circuit, and the detection circuit is configured to process a signal from the Hall sensor; and the detection circuit transmits the signal to a computer by means of an output interface. The present invention achieves the detection of Earth's magnetic field signals and achieves the amplification of the magnetic field signals by means of specially designed iron cores with special shaped structures, so as to extend the detection range of the magnetic field; and the reliability of the magnetic field detection is improved due to the symmetrical and complementary detection of the dual Hall sensors.

Description

A vehicle-mounted antenna for a magnetic parking system Technical Field

[0001] The present invention relates to the technical field of rail transportation, and in particular to a vehicle-mounted antenna for a magnetic parking system. Background Art

[0002] The rail transit industry has experienced rapid growth in recent years. To ensure the safe operation of on-track trains, ground-based equipment typically provides control signals, including departure and stop instructions, track clearing and occupation signals, and more. The magnetic stop system is part of the train's driving safety system and automatic control system. Its primary function is to stop trains in areas restricted by automated train traffic signals and control systems.

[0003] The magnetic parking system is part of the subway's driving safety system and automatic control system. Its main function is to stop the train within the control system's restricted area under the control of the train control signal. The main function of the onboard antenna is to detect the ground magnetic field signal. When the stop signal is detected, it generates a corresponding control signal to the train control system, prompting the train to stop. The current onboard antenna of the magnetic parking system is based on the principle of ferromagnetic relays, which has the following main problems:

[0004] When the magnetic field detection range is small and the ground magnetic field strength is low, the magnetic field energy is insufficient to drive the ferromagnetic relay contacts to operate; the vehicle sensing antenna is based on relay operation, which is not conducive to interfacing with the computer control system.

[0005] Summary of the Invention

[0006] In view of the above problems, the present invention provides a vehicle-mounted antenna for a magnetic parking system, which is used to solve the problems of small magnetic field detection range and low sensitivity of the vehicle-mounted antenna in the current subway magnetic parking system.

[0007] A vehicle-mounted antenna for a magnetic parking system, comprising:

[0008] Several iron cores are provided with an air gap in the middle of the cores. The bottom surface of the iron cores is flat. The iron cores are designed with a special-shaped structure in which the magnetic cross-section is gradually reduced from the bottom surface to the air gap. The magnetic cross-section is gradually reduced. At the air gap where the two iron cores contact, the magnetic cross-section reaches the minimum, which increases the magnetic flux density.

[0009] A Hall sensor is provided in the air gap, and is used to detect the magnetic signal transmitted by the iron core;

[0010] A Hall sensor is connected to a detection circuit, and the detection circuit is used to process the signal of the Hall sensor;

[0011] The detection circuit transmits the signal to the computer through the output interface.

[0012] Furthermore, there are two iron cores, which are placed opposite to each other with an air gap formed in between.

[0013] Furthermore, the iron core is formed by pressing silicon steel sheets with high magnetic conductivity.

[0014] Furthermore, the core includes: a first cuboid, a first trapezoid, a second cuboid, and a second trapezoid connected in sequence;

[0015] The first cuboid has a large cross-sectional area and is used to receive the ground magnetic field;

[0016] The first cuboid is connected to the second cuboid via the first trapezoidal body, and the cross-sectional area gradually decreases;

[0017] The second cuboid is connected to the second trapezoid;

[0018] The magnetic flux lines received by the first cuboid are transferred into the second cuboid, and then gradually reduced in cross-sectional area through the second trapezoidal body to increase the magnetic flux density.

[0019] Furthermore, the Hall sensor is a bidirectional linear Hall sensor, and the output voltage of the linear Hall sensor is linearly related to the direction and magnitude of the magnetic field.

[0020] Furthermore, two Hall sensors are used, and the Hall sensors are installed in opposite directions to perform complementary detection of the magnetic field.

[0021] Furthermore, a self-test coil is wound around the iron core, and the self-test coil is connected to the detection circuit;

[0022] A self-test coil is wound on the iron core and is connected to a detection circuit;

[0023] The self-test coil is wound on a coil bobbin with enameled wire and then placed on an iron core. It is used for self-test after the system is powered on.

[0024] After the system is powered on, a DC current is passed through the self-test coil, generating a magnetic field on the iron core through electromagnetic induction. The Hall sensor between the air gaps of the two iron cores detects the self-test magnetic field and performs self-test judgment on the antenna based on the output signal.

[0025] The present invention has at least the following beneficial effects:

[0026] The present invention realizes the detection of ground magnetic field signals, utilizes a specially designed special-shaped structure iron core to amplify the magnetic field signal, expands the magnetic field detection range, and utilizes dual-channel Hall sensors for symmetrical and complementary detection to improve the reliability of magnetic field detection.

[0027] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0029] FIG1 is a schematic diagram of the antenna principle of the present invention;

[0030] Figure 2 is a schematic diagram of the detection signal principle;

[0031] FIG3 is a schematic diagram of the iron core structure of the present invention;

[0032] FIG4 is a schematic diagram showing the relationship between the linear Hall sensor signal and the magnetic field. DETAILED DESCRIPTION

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0034] In the existing technology, the on-board antenna of the magnetic parking system is based on the principle of ferromagnetic relay, which has the following main problems:

[0035] When the magnetic field detection range is small and the ground magnetic field strength is low, the magnetic field energy is insufficient to drive the ferromagnetic relay contacts to operate; the vehicle sensing antenna is based on relay operation, which is not conducive to interfacing with the computer control system.

[0036] The present invention is used for detecting ground magnetic field signals. It amplifies magnetic field signals through a specially designed special-shaped iron core, expands the magnetic field detection range, and utilizes symmetrical and complementary detection of dual-path Hall sensors to improve the reliability of magnetic field detection.

[0037] As shown in FIG1 , the present invention provides a vehicle-mounted antenna for a magnetic parking system, comprising:

[0038] Several iron cores are provided with an air gap in the middle of the cores. The bottom surface of the iron cores is flat. The iron cores are designed with a special-shaped structure in which the magnetic cross-section is gradually reduced from the bottom surface to the air gap. The magnetic cross-section is gradually reduced. At the air gap where the two iron cores contact, the magnetic cross-section reaches the minimum, which increases the magnetic flux density.

[0039] A Hall sensor is provided in the air gap, and is used to detect the magnetic signal transmitted by the iron core;

[0040] A Hall sensor is connected to a detection circuit, and the detection circuit is used to process the signal of the Hall sensor;

[0041] The detection circuit transmits the signal to the computer through the output interface.

[0042] In specific implementation, as shown in Figure 2, a ground magnetic field device is deployed in the middle of the track. It consists of a permanent magnet and an electromagnet. The magnetic fields generated by the permanent magnet and the electromagnet are in opposite directions. For example, the magnetic field generated by the permanent magnet is from left to right, while the magnetic field generated by the electromagnet is from right to left. When the ground control center signals that the train can pass, the ground electromagnet is energized, generating a magnetic field that cancels out the magnetic field generated by the permanent magnet and generates a magnetic field from right to left. When the onboard antenna detects this magnetic field, the vehicle can pass. When the ground control center signals that the train cannot pass, the ground electromagnet is de-energized, and the permanent magnet generates a magnetic field from left to right. When the onboard antenna detects this magnetic field, the vehicle brakes and stops.

[0043] In one embodiment, there are two iron cores, which are placed opposite to each other with an air gap formed in between.

[0044] In specific implementations, the core's bottom surface serves as the primary receiving surface for the ground's magnetic field lines of flux. To enhance magnetic field detection and reception, the core's bottom surface is maximized. The antenna housing, which contacts the bottom surfaces of the two cores, is constructed from electrically pure iron with high magnetic conductivity. To further amplify the magnetic field intensity at the Hall effect sensor, the core's contoured structure progressively reduces its magnetic cross-section. This gradually decreases until the cross-section reaches its minimum at the air gap where the two cores meet, increasing the magnetic flux density. This design effectively amplifies the ground's magnetic field and expands the detection range of magnetic field signals.

[0045] In one embodiment, the iron core is formed by pressing silicon steel sheets with high magnetic conductivity.

[0046] In one embodiment, the core includes: a first cuboid, a first trapezoid, a second cuboid, and a second trapezoid connected in sequence;

[0047] The first cuboid has a large cross-sectional area and is used to receive the ground magnetic field;

[0048] The first cuboid is connected to the second cuboid via the first trapezoidal body, and the cross-sectional area gradually decreases;

[0049] The second cuboid is connected to the second trapezoid;

[0050] The magnetic flux lines received by the first cuboid are transferred into the second cuboid, and then gradually reduced in cross-sectional area through the second trapezoidal body to increase the magnetic flux density.

[0051] In one embodiment, the Hall sensor is a bidirectional linear Hall sensor, and the output voltage of the linear Hall sensor is linearly related to the direction and magnitude of the magnetic field.

[0052] In specific implementation, within a certain magnetic field range, the output voltage of the linear Hall sensor is linearly related to the direction and magnitude of the magnetic field. Based on this characteristic of the sensor, the direction of the ground magnetic field can be detected.

[0053] In one embodiment, two Hall sensors are used, and the Hall sensors are installed in opposite directions to perform complementary detection of the magnetic field.

[0054] In specific implementation, two Hall sensors are used, and the sensors are installed in opposite directions to detect the magnetic field. When detecting the magnetic field from left to right, the voltage of the first Hall sensor increases and the voltage of the second Hall sensor decreases; when detecting the magnetic field from right to left, the voltage of the first Hall sensor decreases and the voltage of the second Hall sensor increases. Through this symmetrical and complementary detection, the reliability of the magnetic field detection is improved.

[0055] In one embodiment, a self-test coil is wound around the iron core, and the self-test coil is connected to the detection circuit;

[0056] A self-test coil is wound on the iron core and is connected to a detection circuit;

[0057] The self-test coil is wound on a coil bobbin with enameled wire and then placed on an iron core. It is used for self-test after the system is powered on.

[0058] After the system is powered on, a DC current is passed through the self-test coil, generating a magnetic field on the iron core through electromagnetic induction. The Hall sensor between the air gaps of the two iron cores detects the self-test magnetic field and performs self-test judgment on the antenna based on the output signal.

[0059] In order to enable those skilled in the art to better understand the present invention, the principles of the present invention are described as follows with reference to the accompanying drawings:

[0060] The overall structure of the vehicle-mounted antenna of the present invention is shown in Figure 1. It mainly includes two iron cores, two self-test coils, two Hall sensors and a vehicle-mounted antenna processing board.

[0061] The Hall sensor is placed in the air gap between the two iron cores. The iron core is used to gather the magnetic field and is pressed from silicon steel sheets with high magnetic conductivity. The low magnetic resistance characteristics of the silicon steel sheet iron core improve the magnetic induction intensity of the Hall sensor detection position.

[0062] Two self-test coils are made of enameled wire wound on a coil bobbin. The self-test coils are placed on an iron core and are used for self-test after the system is powered on. The self-test logic is as follows: After the system is powered on, a DC current is passed through the self-test coils, generating a magnetic field on the iron core through electromagnetic induction. The Hall effect sensor between the air gaps of the two iron cores detects this self-test magnetic field and performs a self-test judgment on the antenna based on the output signal.

[0063] The core is a specially designed, shaped structure, as shown in Schematic 3 of its three-dimensional structure. The core's bottom surface primarily receives the ground's magnetic field lines of flux. To improve magnetic field detection and reception performance, the core's bottom surface is maximized. The antenna housings, which contact the two core bottom surfaces, are made of electrically pure iron with high magnetic conductivity. To further amplify the magnetic field intensity at the Hall effect sensor, the core's shaped structure features a progressively smaller magnetic cross-section. Structurally, the core consists of two rectangular blocks and two trapezoidal blocks. The larger block has a larger cross-sectional area and receives the ground's magnetic field. A trapezoidal block transitions between the two blocks, gradually reducing their cross-sectional area. The magnetic flux lines received by the larger block transition to the smaller block. Due to the smaller cross-sectional area of ​​the smaller block, the magnetic flux density within its cross-section increases. A trapezoidal block is connected to the rear end of the smaller block, gradually reducing its cross-sectional area and further increasing the flux density. The iron core gradually reduces its magnetic cross-section from the external magnetic field receiving surface to the air gap magnetic field output surface. At the air gap where the two iron cores contact, its magnetic cross-section reaches its minimum, which increases the magnetic flux density. Through this design, the ground magnetic field can be effectively amplified and the magnetic field signal detection range can be expanded.

[0064] The Hall sensor is a bidirectional linear Hall sensor, and the relationship between its output signal and the magnetic field passing through its detection cross section is shown in FIG4 .

[0065] Within a certain magnetic field range, the output voltage of the linear Hall sensor is linearly related to the direction and magnitude of the magnetic field. Based on this characteristic of the sensor, the direction of the ground magnetic field can be detected.

[0066] Two Hall sensors are used with the sensors installed in opposite directions to detect the magnetic field. When detecting a magnetic field from left to right, the voltage of the first Hall sensor increases and the voltage of the second Hall sensor decreases; when detecting a magnetic field from right to left, the voltage of the first Hall sensor decreases and the voltage of the second Hall sensor increases. Through this symmetrical and complementary detection, the reliability of magnetic field detection is improved.

[0067] This invention utilizes a special-shaped iron core to amplify the detected magnetic field, expanding the detection range. It also uses a linear Hall effect sensor to detect the ground magnetic field, while dual Hall effect sensors provide symmetrical and complementary detection to improve magnetic field detection reliability. The Hall effect sensor detects the magnetic field, and the output signal is an analog voltage, which, after analog-to-digital conversion, facilitates interfacing with a computer control system.

[0068] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein; and these modifications or replacements 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 vehicle-mounted antenna for a magnetic parking system, characterized in that: include: A plurality of iron cores, an air gap is formed in the middle of the iron cores, the bottom surface of the iron cores is flat, and the iron cores are designed with a special-shaped structure that gradually reduces the magnetic conductive cross section from the bottom surface to the air gap, and gradually reduces the magnetic conductive cross section. At the air gap where the two iron cores contact, the magnetic conductive cross section reaches the minimum, which plays a role in increasing the magnetic flux density; A Hall sensor is provided in the air gap, and is used to detect the magnetic signal transmitted by the iron core; A Hall sensor is connected to a detection circuit, and the detection circuit is used to process the signal of the Hall sensor; The detection circuit transmits the signal to the computer through the output interface.

2. The vehicle-mounted antenna for a magnetic parking system according to claim 1, characterized in that: There are two iron cores, which are placed opposite to each other with an air gap formed in between.

3. The vehicle-mounted antenna for a magnetic parking system according to claim 1, characterized in that: The iron core is pressed from silicon steel sheets with high magnetic conductivity.

4. The vehicle-mounted antenna for a magnetic parking system according to claim 1, characterized in that: The iron core comprises: a first cuboid, a first trapezoid, a second cuboid and a second trapezoid connected in sequence; The first cuboid has a large cross-sectional area and is used to receive the ground magnetic field; The first cuboid is connected to the second cuboid through a first trapezoidal body transition, and the cross-sectional area gradually decreases; The second cuboid is connected to the second trapezoidal body; The magnetic flux lines received by the first cuboid are transferred into the second cuboid, and then gradually reduced in cross-sectional area through the second trapezoidal body to increase the magnetic flux density.

5. The vehicle-mounted antenna for a magnetic parking system according to claim 1, characterized in that: The Hall sensor is a bidirectional linear Hall sensor, and the output voltage of the linear Hall sensor is linearly related to the direction and magnitude of the magnetic field.

6. The vehicle-mounted antenna for a magnetic parking system according to claim 1, characterized in that: The Hall sensor uses two paths, and the Hall sensors are installed in opposite directions to perform complementary detection of the magnetic field.

7. The vehicle-mounted antenna for a magnetic parking system according to claim 1, characterized in that: A self-test coil is wound on the iron core, and the self-test coil is connected to the detection circuit; The self-test coil is wound on the coil frame and sleeved on the iron core through enameled wire, and is used for self-test after the system is powered on; After the system is powered on, a DC current is passed through the self-test coil, and a magnetic field is generated on the iron core through electromagnetic induction. The Hall sensor between the air gaps of the two iron cores detects the self-test magnetic field, and the antenna is self-tested and judged based on the output signal.