Road surface icing early warning device

Abstract

The utility model provides a road surface icing early warning device which comprises a shell, and an inlet is formed in the bottom of one side in the shell. One end of the spring vibration sheet is fixed at the top in the shell, and an interval with a preset distance is formed between the other end of the spring vibration sheet and the bottom of the shell, so that the spring vibration sheet is in a suspended state; the acceleration sensor is arranged on the side wall of the spring vibration sheet; and the initial excitation assembly is arranged on the inner wall of the shell. According to the road surface icing early warning device, the road surface icing condition can be accurately obtained, the structure of the device is simple through the spring vibration sheet and the acceleration sensor, and the production cost of the device is effectively reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of structural safety monitoring, in particular to a road icing early warning device. Background Art

[0002] Capacitive ice sensor: Utilizes the different dielectric constants of water and ice to detect the ice state by detecting the change in the sensor capacitance value. When ice forms on the sensor surface, the sensor capacitance value will change, thus detecting the ice state. The advantages are simple structure, small size and light weight; the disadvantages are low accuracy and easy to be interfered by the outside world.

[0003] Ultrasonic icing sensor: When the ultrasonic sensor transmits ultrasonic waves to the road surface, if the road surface is not frozen, the ultrasonic waves will be directly reflected back and received by the receiver; if the road surface is frozen, the ultrasonic waves will be refracted and reflected in the ice layer, causing the received echo signal to change. By processing and analyzing the echo signal, it is possible to determine whether the road surface is frozen and the thickness of the ice layer. The advantages are high accuracy and strong anti-interference ability; the disadvantages are complex structure, high cost and high power consumption.

[0004] Optical ice sensor: It uses optical principles to detect the ice state by detecting the change of optical properties on the sensor surface. When the sensor surface is frozen, the reflection and scattering characteristics of light will change, thus detecting the ice state. The advantages are high accuracy and strong anti-interference ability; the disadvantages are complex structure and high cost.

[0005] In summary, among the existing technologies, the traditional sensors for monitoring road icing have low progress, complex structures and high costs. Utility Model Content

[0006] Based on this, the purpose of the present invention is to provide a road icing warning device to at least solve the deficiencies in the above-mentioned prior art.

[0007] The utility model provides a road icing early warning device, comprising:

[0008] A shell, wherein an inlet is provided at a bottom of one side of the shell;

[0009] a spring vibration sheet, one end of which is fixed to the top of the housing, and the other end of which is spaced from the bottom of the housing by a preset distance, so that the spring vibration sheet is in a suspended state;

[0010] An acceleration sensor is arranged on the side wall of the spring vibration sheet;

[0011] An initial excitation component, arranged on the inner wall of the shell;

[0012] The initial excitation component is used to provide external initial excitation to the spring vibration plate, so that the spring vibration plate can obtain damping when the water entering the shell from the inlet freezes, and obtain the road icing conditions through the acceleration sensor.

[0013] Compared with the prior art, the beneficial effects of the utility model are as follows: by placing the spring vibration plate in a suspended state, it is possible to more accurately obtain the damping after water enters the shell and freezes; when the spring vibration plate is working, the initial excitation component can also be used based on the initial vibration state of the spring vibration plate. After the water entering the shell freezes, the vibration state of the spring vibration plate changes. At this time, the acceleration sensor can obtain the change of the spring vibration plate, thereby being able to accurately obtain the road icing conditions; and the spring vibration plate and the acceleration sensor make the device structure simple, effectively reducing its production cost.

[0014] Furthermore, the initial excitation component includes an electromagnet and a coil, the electromagnet is fixed to the inner wall of the shell, and the coil is wound around the electromagnet.

[0015] Furthermore, a waterproof isolation plate is provided in the shell, one end of the waterproof isolation plate is connected to the top of the shell, and the other end of the waterproof isolation plate is arranged on the inner wall of the shell.

[0016] Furthermore, the waterproof isolation plate is bent and the initial excitation component is covered on the inner wall of the shell.

[0017] Furthermore, a collection and transmission component is provided in the shell, the collection and transmission component is electrically connected to the acceleration sensor, and the collection and transmission component is used to transmit the vibration damping information of the spring vibration piece collected by the acceleration sensor.

[0018] Furthermore, the acquisition and transmission component includes an acquisition and transmission module and an antenna. The acquisition and transmission module is arranged on the inner wall of the shell, and the antenna is arranged on the top of the shell. The acquisition and transmission module is respectively connected to the acceleration sensor and the antenna signal.

[0019] Furthermore, a temperature sensor is provided at the bottom of the shell, and the temperature sensor is connected to the signal acquisition and transmission module.

[0020] Furthermore, a filter screen is provided at the inlet.

[0021] Furthermore, the acceleration sensor is a MEMS acceleration sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of the road icing warning device in an embodiment of the utility model.

[0023] Description of main component symbols:

[0024] 1. Filter; 11. Inlet; 2. Shell; 3. Acceleration sensor; 4. Spring vibration sheet;

[0025] 50. Collection and transmission component; 5. Antenna; 6. Collection and transmission module;

[0026] 7. Waterproof isolation board;

[0027] 80. Initial excitation component; 8. Coil; 18. Electromagnet;

[0028] 9. Temperature sensor.

[0029] The following specific implementation manner will further illustrate the present utility model in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0030] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. Several embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0031] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the technical field of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0033] See also Figure 1 , shown is a road icing warning device in an embodiment of the utility model, including a housing 2, a spring vibration sheet 4, an acceleration sensor 3 and an initial excitation component 80.

[0034] An inlet 11 is provided at the bottom of one side of the shell 2. One end of the spring vibration sheet 4 is fixed to the top of the shell 2. The other end of the spring vibration sheet 4 is spaced from the bottom of the shell 2 by a preset distance, so that the spring vibration sheet 4 is in a suspended state. The acceleration sensor 3 is arranged on the side wall of the spring vibration sheet 4. The initial excitation component 80 is arranged on the inner wall of the shell 2. The initial excitation component 80 is used to provide external initial excitation to the spring vibration sheet 4, so that the spring vibration sheet 4 can obtain the damping of the water entering the shell 2 from the inlet 11 when it freezes, and the road icing situation can be obtained through the acceleration sensor 3. In addition, a filter screen 1 is provided at the inlet 11, the main purpose of which is to filter out impurities outside the shell 2 and prevent impurities from entering the shell 2 to interfere with the work of the spring vibration sheet 4; the filter screen 1 is made of rust-proof material and has long-term anti-aging ability. A temperature sensor 9 is provided at the bottom of the shell 2, and the temperature sensor 9 is connected to the acquisition and transmission module 6 for signal connection.

[0035] It can be understood that the road icing warning device is set on the road surface that needs to be monitored. When there is water on the road surface, it will enter the shell 2 through the inlet 11. Since the spring vibration plate 4 is in a suspended state at this time, and the spring vibration plate 4 is vibrated by the initial excitation component 80, the bottom part of the spring vibration plate 4 will contact the water in the shell 2. When the water on the road surface is about to freeze, the spring vibration plate 4 will be solidified by the ice surface, and the state of the spring vibration plate 4 will be changed. Therefore, the state of the road surface can be judged. Since the natural frequency of the spring vibration plate 4 is different when the road surface is dry, waterlogged, and frozen, the state of the road surface dryness, waterlogging, and freezing can be known by measuring and judging the natural frequency of the spring vibration plate 4. At the same time, the auxiliary temperature sensor 9 monitors the road surface temperature as a reference value.

[0036] Considering that the free oscillation amplitude of the spring vibration sheet 4 is relatively small during actual road surface monitoring, it is considered to initiate the free vibration of the spring vibration sheet 4 by applying an external initial excitation. In this embodiment, the acceleration sensor 3 is a MEMS acceleration sensor 3. Due to the characteristics of small size, light weight, low power consumption, high sensitivity, and easy integration, the MEMS acceleration sensor 3 is particularly suitable for being installed on the spring vibration sheet 4 to sense its natural frequency. The MEMS acceleration sensor 3 can be packaged independently and connected to the acquisition module through a data line and a power line. It is recommended to use a MEMS acceleration sensor 3 with analog signal output, which has fewer peripheral circuits. In this way, the MEMS acceleration chip only needs to be fixed on a very small PCB and then a small housing is added. At the same time, the analog signal has a stronger anti-interference ability. The packaged MEMS acceleration sensor 3 can be fixed to a suitable position of the spring vibration sheet 4 by mechanical or structural bonding, and is generally installed in the middle and upper position of the spring vibration sheet 4 so that the vibration of the spring vibration sheet 4 can be sensitively sensed. The operating bandwidth of the MEMS acceleration sensor 3 should be higher than the natural frequency of the spring vibration plate 4 in the air. It is best that the bandwidth is more than 5 times higher than the natural frequency of the spring vibration plate 4 in the air to ensure signal integrity.

[0037] It is worth noting that the spring vibration plate 4 is made of soft magnetic materials such as pure iron, cast iron, silicon steel sheets, etc. For example, soft magnetic materials such as silicon steel sheets are easy to magnetize and demagnetize. The surface treatment can be oxidation, galvanizing, painting and phosphating. These methods can increase the corrosion resistance of the surface of the silicon steel sheet and improve its rust resistance.

[0038] In order to select a suitable static natural frequency operating point (ignoring the natural frequency in air under damping jump conditions), it is necessary to select suitable materials and geometric dimensions. The selection of the static natural frequency point needs to consider the operating bandwidth of the MEMS acceleration sensor 3 at the same time, that is, the operating bandwidth of the MEMS acceleration sensor 3 can cover the highest operating frequency of the spring vibration plate 4.

[0039] It should be explained that when the road surface is dry and there is no water accumulation: the spring vibration plate 4 is equivalent to a cantilever structure. When the air damping is ignored, the vibration of the spring vibration plate 4 is considered to be a simple harmonic vibration, and its natural frequency is

[0040]

[0041] In the formula, f0 represents the natural frequency, k represents the stiffness coefficient of the spring vibration plate 4, and m represents the mass of the spring vibration plate 4.

[0042] According to the theory of material mechanics, according to the stiffness of the spring vibration plate 4 and the moment of inertia of the rectangular cross section of the cantilever beam, its free vibration frequency is It can be seen from the above formula that if the material and geometric dimensions of the spring vibration sheet 4 are known, the natural frequency of the vibration of the spring vibration sheet 4 can be calculated;

[0043] Wherein, f1 represents the natural frequency of the spring vibration piece 4 in the air, l represents the length of the spring vibration piece 4, E represents the elastic modulus of the spring vibration piece 4, and ρ represents the material density of the spring vibration piece 4;

[0044] When there is water on the road surface: the cantilever end of the spring vibration plate 4 will touch the water surface. At this time, it is necessary to consider the influence of water damping on the natural frequency of the vibration of the spring vibration plate 4, that is, Where δ is the damping ratio of the spring vibrating sheet 4 in water, which is equivalent to working in an under-damped state. Since the damping ratio of the spring vibrating sheet 4 in water is much greater than that in air, as long as the appropriate material and geometric dimensions of the spring vibrating sheet 4 are selected, f0 and f can be clearly distinguished. 0z ;f 0z It means that when the spring vibration piece 4 contacts the water, the natural frequency of the spring vibration piece 4 changes from the original f1 to f 0z ,

[0045] When the road surface is frozen, the cantilever end of the spring vibration plate 4 will be solidified by the ice surface, and the spring vibration plate 4 will work in an over-damped state. 0b This means that the spring vibrating plate 4 is frozen and cannot vibrate. At this time, the natural frequency changes from the original f1 to f 0b , at this time f 0b =0, or the vibration signal of the spring vibration plate 4 is very weak.

[0046] The natural frequency measurement of the spring vibration piece 4 can be carried out by using a small and light MEMS acceleration sensor 3. The installation position of the MEMS acceleration sensor 3 should be reasonable, and the influence of its own mass on the spring vibration piece 4 should be small, at least it will not affect the distinction between f0 and f 0z have an impact.

[0047] Specifically, in this embodiment, the initial excitation component 80 includes an electromagnet 18 and a coil 8, the electromagnet 18 is fixed to the inner wall of the shell 2, the coil 8 is wound on the electromagnet 18, a waterproof isolation plate 7 is provided in the shell 2, one end of the waterproof isolation plate 7 is connected to the top of the shell 2, and the other end of the waterproof isolation plate 7 is arranged on the inner wall of the shell 2, the waterproof isolation plate 7 is bent and the initial excitation component 80 is covered on the inner wall of the shell 2.

[0048] It should be noted that the waterproof isolation plate 7 is made of anti-aging plastic material. In this embodiment, ABS is used to waterproof and isolate the circuit part inside the sensor.

[0049] It is understandable that after the electromagnet 18 and the coil 8 are powered on, there is enough magnetic force to attract the spring vibrating sheet 4 to a static position off the center, and then the electromagnet 18 releases the spring vibrating sheet 4 when the power is turned off, and the spring vibrating sheet 4 begins to vibrate freely, which is equivalent to an excitation process. The waterproof isolation plate 7 provided by the bending arrangement can isolate the electromagnet 18, so that the electromagnet 18 will not be affected by the water in the housing 2 to work normally.

[0050] Specifically, in this embodiment, a collection and sending component 50 is provided in the shell 2, and the collection and sending component 50 is electrically connected to the acceleration sensor 3. The collection and sending component 50 is used to receive and send the vibration damping information of the spring vibration piece 4 collected by the acceleration sensor 3. The collection and sending component 50 includes a collection and sending module 6 and an antenna 5. The collection and sending module 6 is arranged on the inner wall of the shell 2, and the antenna 5 is arranged on the top of the shell 2. The collection and sending module 6 is respectively connected to the acceleration sensor 3 and the antenna 5 signals.

[0051] It is worth noting that the acquisition and transmission module 6 has a microcontroller, a wireless transmission unit, an analog signal conditioning circuit, a waveform shaping circuit, a battery and an analog-to-digital converter. The microcontroller is mainly responsible for the working logic of the sensor itself, envelope data transmission, logic control, and its own low power consumption mode;

[0052] Data transmission mainly involves the acceleration sensor 3 communicating with the monitoring center cloud platform or the gateway at the monitoring site, reporting the analysis results of the on-site measurement of the acceleration sensor 3 so that the monitoring center can release road icing news in a timely manner;

[0053] The logic control mainly drives the electromagnet 18 to apply initial excitation to the spring vibration sheet 4, so that the spring vibration sheet 4 can generate free oscillation, which is convenient for the MEMS acceleration sensor 3 to measure; at the same time, the data of the temperature sensor 9 is read to determine whether the road surface temperature meets the conditions for icing;

[0054] Since the device adopts a self-powered working mode, the battery energy is limited. In order to maximize the working time of the device, the microcontroller comprehensively judges the road icing condition by the road surface temperature and the frequency of the spring vibration plate 4. When the road surface does not meet the icing conditions, such as the road surface temperature is higher than a certain value, the working granularity of the device is automatically reduced, such as working once every four hours; when there is water on the road surface and the temperature is low, the device automatically increases the measurement frequency;

[0055] The analog signal conditioning circuit is mainly responsible for amplifying, filtering, and performing signal operations on the analog signal output by the MEMS acceleration sensor 3, and conditioning the signal to a range that meets the measurement range of the analog-to-digital converter;

[0056] The analog-to-digital converter is mainly responsible for converting the acceleration signal into a digital signal, so that the microcontroller can use the frequency domain FFT method to calculate the frequency value of the signal, that is, the current frequency value of the spring vibration plate 4;

[0057] The waveform shaping circuit is mainly responsible for shaping the acceleration signal into a digital pulse signal. The microcontroller can use the time domain equal precision frequency measurement method to obtain the current frequency value of the spring vibration piece 4;

[0058] In addition, the temperature sensor 9 is used to measure the temperature of the water. The temperature value is provided as reference data to the acquisition and transmission module 6 for comparison with the vibration frequency of the spring vibration plate 4 to comprehensively determine the road icing condition.

[0059] It is worth noting that the shell 2 is made of engineering plastic material. In this embodiment, a mixed plastic of ABS and PVC can be used. In addition to providing certain anti-destructive mechanical properties, it can also not block the signal of the wireless transmission antenna 5 of the collection and transmission module 6.

[0060] The collection and transmission module 6 can adopt a distributed working mode, such as using a LoRa transmission module to collect measurements from several sensors in a certain area into the gateway, and comprehensively judge the regional distribution of road icing; it can also use a wireless wide area network module such as NB-IoT to directly report the data to the monitoring center.

[0061] It is worth noting that the device needs to be installed according to the traffic conditions of the road section, such as bends, sections prone to ice, sections prone to water accumulation, etc. At the same time, the installation location of the device cannot affect traffic. After the device measures the alarm value and transmits it to the monitoring center, the monitoring center will display the alarm information and remind passing drivers through the on-site prompt screen.

[0062] In summary, the road icing warning device in the above-mentioned embodiment of the utility model, by putting the spring vibration plate 4 in a suspended state, can more accurately obtain the damping after the water enters the shell 2 and freezes. When the spring vibration plate 4 is working, the initial excitation component 80 can also be based on the initial vibration state of the spring vibration plate 4. After the water entering the shell 2 freezes, the vibration state of the spring vibration plate 4 changes. At this time, the acceleration sensor 3 can obtain the change of the spring vibration plate 4, so as to accurately obtain the road icing conditions, and the spring vibration plate 4 and the acceleration sensor 3 make the device structure simple, effectively reducing its production cost.

[0063] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0064] The above-mentioned embodiments only express several implementation methods of the utility model, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent of the utility model. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the utility model, and these all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A road icing warning device, characterized in that: include: A shell, wherein an inlet is provided at a bottom of one side of the shell; a spring vibration sheet, one end of which is fixed to the top of the housing, and the other end of which is spaced from the bottom of the housing by a preset distance, so that the spring vibration sheet is in a suspended state; An acceleration sensor is arranged on the side wall of the spring vibration sheet; An initial excitation component, arranged on the inner wall of the shell; The initial excitation component is used to provide external initial excitation to the spring vibration plate, so that the spring vibration plate can obtain damping when the water entering the shell from the inlet freezes, and obtain the road icing conditions through the acceleration sensor.

2. The road icing warning device according to claim 1, characterized in that: The initial excitation component includes an electromagnet and a coil. The electromagnet is fixed to the inner wall of the shell, and the coil is wound around the electromagnet.

3. The road icing warning device according to claim 1, characterized in that: A waterproof isolation plate is arranged in the shell, one end of the waterproof isolation plate is connected to the top of the shell, and the other end of the waterproof isolation plate is arranged on the inner wall of the shell.

4. The road icing warning device according to claim 3, characterized in that: The waterproof isolation plate is bent and the initial excitation component is covered on the inner wall of the shell.

5. The road icing warning device according to claim 1, characterized in that: A collection and transmission component is arranged in the shell, the collection and transmission component is electrically connected to the acceleration sensor, and the collection and transmission component is used to transmit the vibration damping information of the spring vibration sheet collected by the acceleration sensor.

6. The road icing warning device according to claim 5, characterized in that: The acquisition and transmission component includes an acquisition and transmission module and an antenna. The acquisition and transmission module is arranged on the inner wall of the shell, and the antenna is arranged on the top of the shell. The acquisition and transmission module is respectively connected to the acceleration sensor and the antenna signal.

7. The road icing warning device according to claim 6, characterized in that: A temperature sensor is provided at the bottom of the shell, and the temperature sensor is connected to the signal acquisition and transmission module.

8. The road icing warning device according to claim 1, characterized in that: A filter screen is provided at the inlet.

9. The road icing warning device according to claim 1, characterized in that: The acceleration sensor is a MEMS acceleration sensor.

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