Railway digital wheel sensor

Abstract

The utility model discloses a railway digital wheel sensor, a digital signal processing board comprises a first amplification circuit, an AD acquisition circuit, an FPGA chip and a second amplification circuit, a wheel sensor inductor comprises a sensor and a magnet, and the magnet is a cylindrical magnet; the wheel sensor inductor is connected with the first amplification circuit through the analog signal output circuit, the first amplification circuit is connected with the collection input end of the AD collection circuit, the output end of the AD collection circuit is connected with the input end of the FPGA chip, one output end of the FPGA chip is connected with the first amplification circuit, and the other output end of the FPGA chip is connected with the second amplification circuit. The second amplification circuit is connected with a railway 5T system through a digital signal output circuit. The wheel sensor converts an analog signal into a digital signal and then outputs the digital signal, the digital signal has a stable characteristic, and an interference signal has no influence on the digital signal; a copper coil is not adopted, so that the cost is greatly reduced; the overall sensitivity is improved, and the adaptability is higher.

Description

Technical Field

[0001] The utility model belongs to the technical field of wheel sensors, and particularly relates to a railway digital wheel sensor. Background Technique

[0002] The wheel sensor of railway vehicles is a key component stuck inside the rail among the trackside devices such as the THDS infrared axle temperature detection system, TFDS dynamic image detection system for freight car operation faults, TPDS ground safety monitoring system for freight car operation status, TADS rail-side acoustic diagnosis system for early faults of freight car rolling bearings, and AEI car number identification system.

[0003] The wheel sensors on the existing market all output analog signals. During the reception and transmission of signals, the analog signals will be interfered. Even though the existing wheel sensors have made great changes in terms of anti-electrical interference as much as possible, these interference signals still exist. If the wheel sensor has poor anti-electrical interference ability, it will lead to large errors in sensor testing, thus affecting the detection results of the railway vehicle bottom detection system.

[0004] The reason is that the analog signal outputs a sine wave, and the magnitude of the sine wave is determined by the speed at which the wheels of the railway vehicle pass. The faster the speed of the wheels, the larger the output waveform, and the slower the speed, the smaller the output waveform. At the back end of the wheel sensor, a device processes this analog signal. Due to the existence of interference, the final processed result may be incorrect. In addition, in the analog signal, it is very likely to be affected by other interferences. Some strong interference signals will submerge or even cancel the normal analog signal. Therefore, some relatively weak analog signals will be completely lost. Especially when some interference signals are much larger than the analog signals, these analog signals cannot be recognized at the back end at all, and these analog signals will be missed.

[0005] For the current wheel sensors, the main interference signals come from the cables between the wheel sensor and the device, the lead wires of the wheel sensor itself, and the interference induced by the coils on the wheel sensor.

[0006] Specifically, 1. The distance between the wheel sensor and the device is usually between 10 and 100 meters, and some are even farther. The cable connecting the wheel sensor and the device will generate interference signals. 2. The lead wires of the wheel sensor itself will also generate interference signals. 3. Since there are coils on the wheel sensor, the more turns of the coil winding, the stronger the ability to receive interference. Therefore, the coil itself will sense some interference signals. Although some of the interference signals generated by these interference sources are very weak, they actually exist.

[0007] Moreover, since the analog signal generated by the wheel sensor also belongs to a type of alternating voltage, this analog signal does not have a consistent magnitude and there will be fluctuations during actual use. When the signal is weak and encounters interference signals, the interference signals generated by the above-mentioned interference signal sources also belong to a type of alternating voltage. When the weak analog signal encounters the interference signal, it may become weak or be directly cancelled out.

[0008] In addition, existing wheel sensors are all implemented by the cooperation of a magnet and a copper coil. If the existing wheel sensor is far from the wheel, a large amount of copper wire will be required. Since copper wire is expensive, the cost is high. If the existing wheel sensor is installed close to the wheel, it will be because the wheels of the inspection vehicle are lower than the actual normal wheels. Therefore, when the inspection vehicle passes by, the wheel sensor will be blocked. Therefore, the wheel sensor needs to be manually removed before the inspection vehicle passes.

[0009] Therefore, how to change the existing wheel sensor so that the signal it outputs can be accepted as much as possible while being stable and reliable, and with low cost, has become the direction of efforts of those skilled in the art. Utility Model Content

[0010] The purpose of the present utility model is to provide a railway digital wheel sensor, which converts the analog signal output by the wheel sensor into a digital signal and then outputs it. The digital signal has stable characteristics and is not affected by interference signals; and the use of copper coils is not adopted, which can greatly reduce the cost; it can completely solve the deficiencies of the above-mentioned existing technologies.

[0011] The purpose of the present utility model is achieved by the following technical solutions: A railway digital wheel sensor includes a wheel sensor inductor and a digital signal processing board. The digital signal processing board includes a first amplification circuit, an AD acquisition circuit, an FPGA chip, and a second amplification circuit. The wheel sensor inductor includes a sensor and a magnet. The magnet is a cylindrical magnet and is fixedly placed above the digital signal processing board; the wheel sensor inductor is connected to the first amplification circuit through an analog signal output circuit. The first amplification circuit is connected to the acquisition input end of the AD acquisition circuit. The output end of the AD acquisition circuit is connected to the input end of the FPGA chip. One output end of the FPGA chip is connected to the first amplification circuit. The other output end of the FPGA chip is connected to the second amplification circuit. The second amplification circuit is connected to the railway 5T system through a digital signal output circuit.

[0012] As a preferred method, it further includes a support frame, and the support frame is fixed on the digital signal processing board.

[0013] As a preferred method, the top surface of the support frame is provided with a circular fixing ring with a notch, and the magnet is fixed in the fixing ring.

[0014] As one of the preferred embodiments, it further includes a magnet steel housing. Installation grooves are provided at both ends of the magnet steel housing. The magnet steel housing is fixed to the inner side of the railway track by bolts passing through the installation grooves. A wire outlet is also provided on the side of the magnet steel housing.

[0015] As one of the preferred embodiments, a power supply device is provided on the digital signal processing board, and the power supply device is connected to an external power source.

[0016] Compared with the prior art, the beneficial effects of the present utility model are as follows: A digital wheel sensor has the following advantages:

[0017] 1. The wheel sensor inductor group composed of a sensor and a magnet does not require the use of a copper coil, reducing costs.

[0018] 2. The analog signal output by the wheel sensor is converted into a digital signal, which can be fully received, the signal is stable, and the existing interference signals have no effect on it, making the detection results of the later railway vehicle bottom detection system more accurate.

[0019] 3. The reference voltage output from the first amplifier circuit has positive and negative values. The first amplifier circuit is controlled by the FPGA to make the output reference voltage 0, making the measurement more accurate and capable of long-distance identification.

[0020] 4. The overall sensitivity is improved and the adaptability is stronger. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is the principle structure block diagram of the present utility model.

[0022] Figure 2 is the external structure schematic diagram of the present utility model.

[0023] Figure 3 is the schematic diagram of the magnetic force of the present utility model being cut.

[0024] Figure 4 is the waveform schematic diagram of the digital signal of the present utility model.

[0025] Figure 5 is the structure schematic diagram of the magnet steel housing of the present utility model.

[0026] Figure 6 is the structure schematic block diagram after the present utility model is placed in the magnet steel housing.

[0027] In the attached drawings: wheel sensor inductor 1, first amplifier circuit 2, digital signal processing board 3, power supply 4, analog signal output circuit 5, AD acquisition circuit 6, FPGA chip 7, second amplifier circuit 8, digital signal output circuit 9, railway 5T system 10, magnet 11, support frame 12, fixing ring 13, magnet housing 14, wire outlet 15, installation groove 16. Specific implementation mode

[0028] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

[0029] As Figure 1-6 shown, a railway digital wheel sensor includes a wheel sensor inductor 1 and a digital signal processing board 3.

[0030] Among them, the wheel sensor inductor 1 includes a sensor and a magnet 11. The magnet 11 is a cylindrical magnet and is fixedly placed above the digital signal processing board. The wheel sensor inductor group composed of the sensor and the magnet does not require the use of a copper coil, reducing the cost.

[0031] As Figure 2 shown, in order to fix the cylindrical magnet, a support frame 12 is provided. The support frame 12 is composed of four support legs and a support flat plate. The support legs are fixed on the digital signal processing board, and the support flat plate is fixed on the support legs. A circular fixing ring 13 with a notch is provided on the support flat plate on the top surface of the support frame. The magnet 11 is fixed in the fixing ring 13, and the fixing ring can prevent the magnet from shaking and affecting the magnetic field of the magnet. Attached Figure 3 is only one of the setting methods, and the magnet can also be fixed by other methods. As long as the magnet is a cylindrical circular magnet, its magnetic field stability can be guaranteed. The magnet utilizes its naturally formed magnetic field. When the train wheel passes by, it can form a cutting of the magnetic force lines, thereby generating a signal, as Figure 3 shown.

[0032] In addition, as Figure 5 and Figure 6As shown in the figure, in order to facilitate the overall installation, a magnetic steel housing 14 is also provided. The interior of the magnetic steel housing is used to install the digital signal processing board, as well as the magnet and the fixing device of the magnet. Installation grooves 16 are provided at both ends of the magnetic steel housing. The magnetic steel housing is fixed to the inner side of the railway track through bolts passing through the installation grooves. An electric wire outlet 15 is also provided on the side of the magnetic steel housing to neatly accommodate the digital signal processing board and other electric wires and then connect them to the outside through this outlet.

[0033] In addition, a power supply device is provided on the digital signal processing board, and the power supply device is connected to an external power supply 4.

[0034] In addition, as Figure 1 shown, the digital signal processing board 3 includes a first amplifier circuit 2, an AD acquisition circuit 6, an FPGA chip 7, and a second amplifier circuit 8. The wheel sensor 1 is connected to the first amplifier circuit 2 through an analog signal output circuit 5. The first amplifier circuit 2 is connected to the acquisition input end of the AD acquisition circuit 6. The output end of the AD acquisition circuit 6 is connected to the input end of the FPGA chip 7. One output end of the FPGA chip 7 is connected to the first amplifier circuit 2. The other output end of the FPGA chip 7 is connected to the second amplifier circuit 8. The second amplifier circuit 8 is connected to the railway 5T system 10 through a digital signal output circuit 9. When the entire wheel sensor does not sense the wheel, the reference voltage output by the first amplifier circuit may be positive or negative, which will directly affect the signal acquisition of the subsequent AD acquisition circuit. Therefore, by connecting the FPGA chip to the first circuit, the FPGA chip can control the output of the first amplifier circuit to make its reference voltage 0. By setting two amplifier circuits on the digital signal processing board, the overall sensitivity can be improved and its adaptability can be enhanced.

[0035] The present utility model can render existing interference signals ineffective, mainly because: as Figure 4 shown, the digital signal is equivalent to a generated DC voltage, and the signal generated by the interference source belongs to an AC voltage, and the AC voltage no longer affects the DC voltage of the digital signal. A series of AI algorithms are preset in the FPGA chip in the digital signal processing board. The AI algorithms remove the interference signals of the wheel sensor itself and the coil, and at the same time filter out the magnitude of the interference signals through the AI algorithms. The existing output analog signals have certain requirements for the subsequent processor. Especially for some analog signals with weak signals, they will be missed if not received. Now the digital signal output can stabilize its magnitude, and only requires the subsequent processor to be able to receive it, thus reducing the requirements for the subsequent processor.

[0036] The processing process of the digital signal processing board:

[0037] The AD acquisition module converts analog signals into digital signals. In the AD acquisition module, through software processing of the AD-acquired data, the influence of interference signals is minimized, and acquisition filtering is performed on data acquisition. Currently, there are many methods for data acquisition filtering, which can be achieved by existing technologies.

[0038] Even though acquisition filtering is performed on the AD acquisition, the AD acquisition still converts both the acquired wheel sensor signals and interference signals into digital signals. The converted digital signals are processed by an FPGA chip (PGA (Field-Programmable Gate Array), that is, a field-programmable gate array) with a pre-written corresponding program. Here, the processing method for interference signals is pre-written, especially for identifying and filtering interference signals, and the identification and output of useful normal signals are also pre-written. Even though the interference signal source is dynamically changing, due to the identification of interference signals by the FPGA, interference signals can be effectively excluded.

[0039] After processing, only normal signals remain in the digital signals. The normal signals are amplified in signal power through an amplifier circuit for convenient subsequent processing. The normal digital signals are then transmitted to the receiving end through a digital signal output circuit. Here, the receiving end is the railway 5T system and other systems. Because of the output digital signals, in the railway 5T system and other systems, compared with existing receiving device circuit boards, some settings can be simplified. Other systems can be any other terminal devices.

[0040] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A railway digital wheel sensor, comprising a wheel sensor inductor and a digital signal processing board, characterized in that: The digital signal processing board includes a No. 1 amplifier circuit, an AD acquisition circuit, an FPGA chip and a No. 2 amplifier circuit. The wheel sensor inductor includes a sensor and a magnet. The magnet is a cylindrical magnet and is fixedly placed above the digital signal processing board. The wheel sensor inductor is connected to the No. 1 amplifier circuit through an analog signal output circuit. The No. 1 amplifier circuit is connected to the acquisition input end of the AD acquisition circuit. The output end of the AD acquisition circuit is connected to the input end of the FPGA chip. One output end of the FPGA chip is connected to the No. 1 amplifier circuit. The other output end of the FPGA chip is connected to the No. 2 amplifier circuit. The No. 2 amplifier circuit is connected to the railway 5T system through the digital signal output circuit.

2. The railway digital wheel sensor according to claim 1, characterized in that: The device also comprises a supporting frame which is fixed on the digital signal processing board.

3. The railway digital wheel sensor according to claim 2, characterized in that: A circular fixing ring with a notch is arranged on the top surface of the supporting frame, and the magnet is fixed in the fixing ring.

4. The railway digital wheel sensor according to claim 3, characterized in that: It also includes a magnetic steel shell, both ends of which are provided with mounting grooves, the magnetic steel shell is fixed to the inner side of the rail by bolts passing through the mounting grooves, and the side of the magnetic steel shell is also provided with a wire outlet.

5. The railway digital wheel sensor according to claim 1, characterized in that: The digital signal processing board is provided with a power supply device, which is connected to an external power source.

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