Barometric pressure sensor and shock wave signal monitoring and alarm device using the same

Abstract

The application discloses a barometric pressure sensor and a shock wave signal monitoring and alarming device adopting the same. The barometric pressure sensor comprises a hard shell with a sealed cavity inside, and a pipe joint with a shock wave signal inlet hole in the middle is mounted on the hard shell. A double pressure sensor and a circuit board are arranged in the sealed cavity. The double pressure sensor is used for detecting the barometric pressure entering from the shock wave signal inlet hole and transmitting two collected pressure measurement values to the circuit board. The circuit board is used for collecting the pressure measurement values sent by the double pressure sensor, obtaining final pressure data through binary multiple fitting of the two pressure measurement values, and performing pressure threshold value determination according to the pressure data. When the positive and negative pressure alarm threshold values are exceeded, a pulse on-off signal is output. A socket is further arranged on the shell and connected with the signal output end of the circuit board, and is used for outputting the pulse on-off signal outward.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of pressure wave monitoring, in particular to a kind of air pressure sensor and the shock wave signal monitoring and alarm device using the sensor. BACKGROUND

[0002] At present, the pressure sensor in the shock wave signal detection device mostly uses imported chip from abroad as the front end shock wave signal coupling unit, generally gives pressure value, no pulse alarm signal output. Thus, the device cost is high, and the problems such as long transportation cycle. And domestic pressure sensor, due to the lower measurement error, mostly can not meet the measurement error requirement. SUMMARY

[0003] In view of the above-mentioned deficiencies in the prior art, the purpose of the present application is to provide a kind of, solve the problem.

[0004] In order to solve the above technical problems, the technical scheme adopted by the present application is as follows:

[0005] The application relates to a kind of air pressure sensors, including rigid shell with closed cavity inside, a pipe joint with shock wave signal inlet hole in the middle is installed on the rigid shell, one end of the shock wave signal inlet hole is connected with atmosphere environment, the other end is connected with closed cavity;A double pressure sensor and circuit board are arranged in the closed cavity, the double pressure sensor has an air inlet connected with the shock wave signal inlet hole, for detecting the air pressure entered from the shock wave signal inlet hole, and the two pressure measurement values collected are transmitted to the circuit board;The circuit board is used to collect the pressure measurement value sent by the double pressure sensor, and after two pressure measurement values are fitted, the final pressure data is obtained, and pressure threshold value is determined according to the pressure data, and pulse switch signal is output when exceeding positive and negative pressure alarm threshold;A socket is further arranged on the shell, the socket is provided with power input and signal output, the power input is connected with the power circuit of the circuit board to supply power for the circuit board, and the signal output is connected with the signal output end of the circuit board to output the final pressure data or pulse switch signal transmitted by the circuit board outward. In this way, two pressure measurement values can be collected after the environmental air pressure is connected from the wiring pipe, then the two pressure measurement values are transmitted to the circuit board, and the pressure measurement value and pulse switch signal are output when exceeding positive and negative pressure alarm threshold after two pressure measurement values are fitted by the circuit board. The measurement error can be reduced by measuring two pressure measurement values and fitting the measurement data, the pressure measurement error is within + / - 20Pa, the measurement accuracy is improved, and the requirement of national production of parts can be realized. The air inlet of the double pressure sensor is connected with the shock wave signal inlet hole of the wiring pipe, so that the air pressure entering the double pressure sensor is in a sealed environment, and the measurement accuracy is not affected. The rigid shell protects the double pressure sensor and the circuit board, and prevents the double pressure sensor and the circuit board from being affected by the atmospheric environment in harsh environment.

[0006] Further, the rigid shell is made of 316 stainless steel, including detachably connected upper shell and lower base, the lower base is interference-fitted in the upper shell, and the upper shell and the lower base are connected to form the closed cavity in the middle. In this way, the material of the rigid shell can meet the working requirements of the pressure sensor in harsh environment such as salt spray and acid. The rigid shell composed of detachably connected upper shell and lower base is convenient for installation and maintenance of the double pressure sensor and the circuit board.

[0007] Further, the upper shell is a cylindrical body with a sealed upper end, and the lower base is a cylindrical body with a sealed lower end; the lower end of the upper shell is bent outward horizontally to form a connecting ring, and the lower end of the lower base extends outward horizontally beyond the cylindrical body to form a connecting part matched with the connecting ring; the connecting ring and the connecting part are in close contact and are connected and fixed by a plurality of fasteners. In this way, the upper shell and the lower base are fitted together with interference, and are also connected and fixed by fasteners, so that the installation structure is stable and the sealing effect is good.

[0008] Further, a plurality of connecting holes are uniformly arranged on the connecting ring and the connecting part in a circumferential direction, and the connecting holes on the connecting ring are arranged one-to-one with the connecting holes on the connecting part. In this way, the connecting holes facilitate the arrangement of fasteners.

[0009] Further, an annular step is arranged inside the connecting ring, and a sealing ring matched with the annular step is arranged in the annular step. In this way, the sealing ring is arranged between the lower base and the upper shell, thereby further sealing the connection part and optimizing the sealing performance.

[0010] Further, the pipe joint is made of 316 stainless steel, and a sealing ring matched with the lower base is arranged on the pipe joint. In this way, after the pipe joint is assembled, the connection part and the lower base are further sealed by the sealing ring, which can effectively ensure the sealing performance of the sealed cavity, and ensure that the ambient air pressure enters the double-pressure sensor without leakage, thereby effectively ensuring the accuracy of the measurement data.

[0011] Further, a step is arranged on the inner wall of the upper end of the cylindrical body of the lower base, and the circuit board is assembled on the step. In this way, the circuit board is assembled on the lower base and fixed by being clamped on the step, so that the installation structure is stable.

[0012] Further, the circuit board is made of a copper foil epoxy glass cloth board, and the communication circuit, temperature acquisition circuit, MCU circuit, pressure acquisition circuit and power supply circuit are integrated on the circuit board. In this way, the circuit board has an external current input for power supply, and the MCU circuit is used for data reception, calculation and analysis, and the pressure acquisition circuit is used for collecting signals from the double-pressure sensor and sending the collected data to the MCU circuit.

[0013] Further, the socket is mounted on the upper shell, and the double-pressure sensor and the pipe joint are mounted on the lower base, wherein the shell of the double-pressure sensor is made of stainless steel and is a piezoresistive sensor. In this way, the piezoresistive sensor can effectively ensure a large measurement range, a high-pressure impact overload capacity, a high signal-to-noise ratio, and a pressure sensor measurement error of less than 20 Pa in air.

[0014] The shock wave signal monitoring and alarming device comprises the air pressure sensor and an alarm connected with the signal output port of the air pressure sensor, the alarm is used for receiving the positive pressure or negative pressure alarm signal and starting after receiving the signal.

[0015] Compared with the prior art, the present application has the following beneficial effects:

[0016] 1. The mode of measuring two pressure measurement values at one time and performing binary multiple fitting on the measurement data can reduce measurement error, realize pressure measurement error within ±20Pa, improve measurement accuracy, and realize the requirement of national production of parts.

[0017] 2. The product is made of stainless steel and can work in a harsh environment such as salt spray and acid.

[0018] 3. The device can output an alarm signal for the shock wave signal generated by explosion in the environment and realize the alarm function. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 It is a cross-sectional structure diagram of the air pressure sensor in the embodiment.

[0020] Figure 2 It is a connection structure diagram of the air pressure sensor and the alarm in the embodiment. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme of the embodiments of the present application will be described clearly and completely in combination with the drawings of the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application.

[0022] It should be noted that similar reference numerals and letters refer to like items in the accompanying drawings, and therefore, once an item is defined in one drawing, it is not necessary to further define and explain it in subsequent drawings. In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present application is usually placed in use, and are merely for the convenience of describing the present application and simplifying the description, and therefore, cannot be construed as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, cannot be construed as limiting the present application. In addition, the terms "first", "second", "third", and the like are merely used to distinguish the description, and cannot be construed as indicating or implying relative importance. In addition, the terms "horizontal", "vertical", and the like do not mean that the components must be absolutely horizontal or vertical, but can be slightly inclined. For example, "horizontal" only means that it is more horizontal than "vertical", and does not mean that the structure must be absolutely horizontal, but can be slightly inclined. In the description of the present application, it should also be noted that, unless otherwise explicitly specified and limited, the terms "provided", "mounted", "connected", "linked" should be understood broadly, for example, can be fixedly connected, can be detachably connected, or integrally connected; can be mechanically connected, or electrically connected; can be directly connected, or indirectly connected through an intermediate medium; can be internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0023] As shown in Figure 1 The present embodiment provides a barometric pressure sensor, which comprises a hard shell 1 with a sealed cavity inside, a pipe joint 2 with a shock wave signal inlet hole 21 in the middle is mounted on the hard shell 1, one end of the shock wave signal inlet hole 21 is connected with the atmosphere, and the other end is connected with the sealed cavity; a double pressure sensor 3 and a circuit board 4 are arranged in the sealed cavity, the double pressure sensor 3 has an air inlet connected with the shock wave signal inlet hole, which is used to detect the air pressure entering from the shock wave signal inlet hole 21, and transmit the two collected pressure measurement values to the circuit board 4; the circuit board 4 is used to collect the pressure measurement values sent by the double pressure sensor 3, and after two times of binary multiple fitting, the final pressure data is obtained, and the pressure threshold value is determined according to the pressure data, and the pulse on-off signal is output when the positive and negative pressure alarm threshold values are exceeded; a socket 5 is further arranged on the shell 1, the socket 5 is internally provided with a power input port and a signal output port, the power input port is connected with the power circuit of the circuit board 4 to supply power for the circuit board 4, and the signal output port is connected with the signal output end of the circuit board 4 to externally output the final pressure data or the pulse on-off signal transmitted by the circuit board 4.

[0024] In order to meet the working conditions in harsh environment, the hard shell 1, double pressure sensor shell and pipe joint 2 in the embodiment are made of 316 stainless steel.

[0025] In order to facilitate the assembly of double pressure sensor 3 and circuit board 4, the hard shell 1 in the embodiment is composed of detachable upper shell 11 and lower base 12, the upper end of the lower base 12 is interference fit in the upper shell 11, and the upper shell 11 is connected with the lower base 12 to form the closed cavity 13 in the middle. Specifically, the upper shell 11 is a cylindrical body with a sealed upper end, and the lower base 12 is a cylindrical body with a sealed lower end; the lower end of the upper shell 11 is bent outward horizontally to form a connecting ring 14, and the lower end of the lower base 12 extends outward after the lower end of the lower base 12 extends outward to form a connecting part 15 which is matched with the connecting ring 14; the connecting ring 14 and the connecting part 15 are in close contact and are connected and fixed by a plurality of fasteners 6.

[0026] Of course, in order to facilitate the assembly of the fasteners 6, a plurality of connecting holes are uniformly arranged on the connecting ring 14 and the connecting part 15, and the connecting holes on the connecting ring are arranged one by one corresponding to the connecting holes on the connecting part.

[0027] If the air pressure leaks during transmission, it will seriously affect the detection accuracy of the double pressure sensor, therefore, in order to ensure the sealing performance of the assembly, an annular step is arranged inside the connecting ring 14, and a sealing ring 7 matched with the annular step is arranged in the annular step; a sealing ring 8 matched with the lower base 12 is sleeved on the pipe joint 2, the sealing ring 8 is made of rubber, and the sealing ring 7 is a conductive sealing ring.

[0028] Further, a step is arranged on the inner wall of the upper end of the cylindrical body of the lower base 12, and the circuit board 4 is assembled on the step.

[0029] Further, the circuit board 4 adopts a copper-clad epoxy glass cloth board, and the communication circuit, temperature acquisition circuit, MCU circuit, pressure acquisition circuit and power supply circuit are integrated on the circuit board 4, wherein the communication circuit is used for receiving and sending signals, the power supply circuit is used for electrically connecting with the power supply to supply power to the circuit board, and the pressure acquisition circuit is used for acquiring the measurement data sent by the double pressure sensor, the MCU circuit is provided with a calculator chip, which is used for obtaining the final measurement pressure data after binary multiple fitting of the received measurement data, and outputting the pulse switch signal according to the final measurement pressure data and the set positive and negative pressure alarm threshold.

[0030] Further, the socket 5 is installed on the upper shell 11, and the double pressure sensor 3 and the pipe joint 2 are installed on the lower base 12, wherein the shell of the double pressure sensor 3 is made of stainless steel, and is a piezoresistive sensor.

[0031] As Figure 2 shown in the embodiment, the shock wave signal monitoring and alarming device also comprises a pressure sensor as described above and an alarm 8 connected to the signal output port of the pressure sensor, wherein the alarm 8 is used to receive the positive pressure or negative pressure alarm signal and start after receiving the signal.

[0032] The shock wave signal monitoring method using the above pressure sensor is as follows: the pressure sensor and the pressure standard source are placed in the same pressure cavity, and the two pressure measurement values measured by the pressure sensor are calibrated; after the double pressure sensor detects the data, the measurement data is sent to the circuit board, and the measurement data is fitted by the circuit board, and the final pressure measurement signal is output; then the pressure sensor is placed in the measured environment for pressure value measurement, and after the final pressure measurement data is obtained, the final pressure measurement data is compared with the alarm threshold value according to the positive and negative pressure alarm threshold value, to determine whether the final pressure measurement data reaches the alarm threshold value, and if the threshold value is reached, the pulse switch quantity signal is output.

[0033] Since the temperature has a great influence on the pressure measurement value, there is a great difference between the pressure measured at different temperatures and the standard source without temperature compensation, and the pressure needs to be compensated and calibrated in different temperature ranges. Specifically, the specific steps of calibrating the two pressure measurement values by the above circuit board are as follows: first, the two pressure measurement values of the pressure sensor are fitted by 2 multiple fitting to obtain the temperature compensated pressure data, and then the Kalman filtering algorithm is used to fuse the collected two pressure values and temperature data to obtain the final pressure data.

[0034] Specifically, 2 temperature 4 times and pressure 1 time fitting is used.

[0035] The corresponding relationship of each coefficient is shown in Table 1:

[0036] Parameter 1 2 3 4 5 6 7 8 9 10 x^ 0 1 2 3 4 0 1 2 3 4 y^ 0 0 0 0 0 1 1 1 1 1 Coefficient P00 P10 P20 P30 P40 P01 P11 P21 P31 P41

[0037] Table 1

[0038] In the table, f(x, y) is the calibrated pressure; x is the measured temperature; and y is the measured pressure.

[0039] Pressure calculation function:

[0040] f(x, y) = p00 + p10 * x + p01 * y + p20 * x^2 + p11 * x * y + p30 * x^3 + p21 * x^2 * y +

[0041] p40 * x^4 + p31 * x^3 * y

[0042] Coefficients (with 95% confidence bounds):

[0043] p00 = 3.933 (3.337, 4.529)

[0044] p10 = -0.07944 (-0.1122, -0.04673)

[0045] p01 = 0.9997 (0.999, 1)

[0046] p20 = -0.0003608 (-0.001146, 0.0004244)

[0047] p11 = -0.0001049 (-0.0001439, -6.584e-05)

[0048] p30 = -3.547e-06 (-2.128e-05, 1.419e-05)

[0049] p21 = 4.818e-06 (4.175e-06, 5.46e-06)

[0050] p40 = 4.369e-07 (1.817e-07, 6.922e-07)

[0051] p31 = -5.953e-08 (-7.968e-08, -3.938e-08)

[0052] The pressure calibration function is as follows:

[0053] PRESS = -(p40*x^4 + p30*x^3 + p20*x^2 + p10*x + p00 - y) / (p41*x^4 + p31*x^3 + p21*x^2 + p11*x + p01).

[0054] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application and not to limit the technical solutions. Those of ordinary skill in the art should understand that modifications or equivalent replacements to the technical solutions of the present application without departing from the spirit and scope of the technical solutions should be covered in the scope of the claims of the present application.

Claims

1. A gas pressure sensor comprising a hard case having a closed cavity inside, characterized by, A pipe joint with a shock wave signal inlet hole in the middle is mounted on the hard shell, one end of the shock wave signal inlet hole is connected with the atmosphere, and the other end is connected with the sealed cavity; a double pressure sensor and a circuit board are arranged in the sealed cavity, the double pressure sensor has an air inlet connected with the shock wave signal inlet hole, and the double pressure sensor is used for detecting the air pressure entering from the shock wave signal inlet hole and transmitting two pressure measurement values collected to the circuit board; The circuit board adopts a copper foil epoxy glass cloth board, and communication circuit, temperature acquisition circuit, MCU circuit, pressure acquisition circuit and power supply circuit are integrated on the circuit board, which is used for collecting the pressure measurement values sent by the double pressure sensor, obtaining final pressure data through binary multiple fitting of the two pressure measurement values, and performing pressure threshold value determination according to the pressure data, and outputting a pulse switching value signal when the positive and negative pressure alarm thresholds are exceeded; the specific steps of calibrating the two pressure measurement values by the circuit board are as follows: firstly, the air pressure sensor adopts 2 multiple fitting of the two pressure measurement values to obtain temperature-compensated pressure data, and then the final pressure data is obtained by fusing the two pressure values and temperature data collected by using Kalman filtering algorithm; A socket is further arranged on the shell, the socket is internally provided with a power input port and a signal output port, the power input port is connected with the power supply circuit of the circuit board to supply power to the circuit board, and the signal output port is connected with the signal output end of the circuit board to externally output the final pressure data or the pulse switching value signal transmitted by the circuit board.

2. The air pressure sensor according to claim 1, characterized in that, The hard shell is made of 316 stainless steel and includes a detachable upper shell and a lower base, the lower base is interference-fitted in the upper shell, and the upper shell and the lower base are connected to form the sealed cavity in the middle.

3. The air pressure sensor according to claim 2, characterized in that The upper shell is a cylindrical body with a sealed upper end, and the lower base is a cylindrical body with a sealed lower end; the lower end of the upper shell is outwardly bent horizontally to form a connecting ring, and the lower end of the lower base is outwardly extended to form a connecting part outside the cylindrical body; the connecting ring and the connecting part are tightly connected and fixed by a plurality of fasteners.

4. The air pressure sensor according to claim 3, characterized in that A plurality of connecting holes are uniformly arranged on the connecting ring and the connecting part in a circumferential direction.

5. The air pressure sensor according to claim 3 or 4, characterized in that An annular step is arranged inside the connecting ring, and a sealing ring is arranged in the annular step.

6. The air pressure sensor according to claim 2 or 3 or 4, characterized in that, The pipe joint is made of 316 stainless steel and is provided with a sealing ring tightly fitted on the lower base.

7. The air pressure sensor according to claim 2 or 3 or 4, characterized in that, A step is arranged on the inner wall of the upper end of the cylindrical body of the lower base, and the circuit board is assembled on the step.

8. The air pressure sensor according to claim 2 or 3 or 4, characterized by, The socket is mounted on the upper shell, the double pressure sensor and the pipe joint are mounted on the lower base, and the shell of the double pressure sensor is made of stainless steel and is a piezoresistive sensor.

9. A shockwave signal monitoring and alerting device, characterized by The air pressure sensor of any one of claims 1-7 and an alarm connected with the signal output port of the air pressure sensor are included, and the alarm is used for receiving a positive pressure or negative pressure alarm signal and starting after receiving the signal.

Images