A vibration detection sensor for liquid detection based on the vibration principle and its application

Abstract

The present invention relates to the fields of biomedicine and sensor technology, and discloses a vibration detection sensor for liquid detection based on the vibration principle and its application. The vibration detection sensor includes a columnar insulator, at least two metal conductors with different heights arranged on the surface of the columnar insulator, and pins arranged on the columnar insulator for connecting with the metal conductors; the metal conductors with different heights are not connected to each other; the pins are respectively connected to the metal conductors with different heights. The vibration detection sensor forms a conductive path between the metal conductors with different heights by arranging the metal conductors with different heights and utilizing the conductivity of the liquid; when resonance occurs, the vibrating liquid forms a conductive path between the metal conductors with different heights, is connected to the detection circuit through the pins, and the signals output by different metal conductors are detected, so as to reflect the change of the liquid resonance amplitude and the change of the resonance frequency, and to master the change process of the physical and chemical properties of the liquid. The vibration detection sensor is more sensitive and the detection result is more accurate.

Description

Technical Field

[0001] The present invention relates to the fields of biomedicine and sensor technology, and particularly to a vibration detection sensor for liquid detection based on the vibration principle and its application. Background Art

[0002] Resonance is also called "mechanical resonance". It is a phenomenon in which the amplitude of an oscillating system increases sharply when the frequency of the external force acting on the system is the same as or very close to the natural oscillation frequency of the system under the action of a periodic external force.

[0003] Any liquid has its specific electrical resonance frequency, and the electrical resonance frequency is related to the properties of the liquid itself. When any property of the liquid (such as composition, conductivity, concentration, pH value, density, viscosity, etc.) changes, then the electrical resonance frequency of the liquid will also change accordingly. Therefore, this electrical resonance characteristic of the liquid can be used to measure the change in the resonance frequency during the change of the physical and chemical properties of the liquid, and further understand the physical and chemical properties of the liquid, etc.

[0004] The prior art (Research on the Blood Coagulation Test Method Based on the Liquid Electrical Resonance Principle, Zhou Yukun, June 15, 2009) uses a liquid resonance measurement device to measure the electrical resonance frequency of plasma. The measurement system includes a solution to be measured, a finger fork type sensor, an oscillation circuit, a precision frequency detector such as SP312, USB data transmission, PC data display, and a corresponding upper computer software part. The prior art (Liquid Resonance Sensing Method and System, CN102809597A) discloses that the properties of liquid such as viscoelasticity, density, composition, and its concentration can be characterized by the natural frequency of the liquid. Under the action of an alternating excitation oscillation signal, the liquid generates resonance. When the properties of the liquid change, its resonance frequency will change accordingly. The disclosed sensing system consists of a gold-plated film finger fork microelectrode array resonance sensor, an excitation oscillator, a pickup, a single-chip microcomputer, and a computer.

[0005] The finger fork type sensors, excitation oscillators, pickups, etc. used in the above-mentioned disclosed materials have problems such as complex structure, high manufacturing difficulty, low precision, and poor repeatability. Summary of the Invention

[0006] In order to solve the deficiencies of the above-mentioned prior art, the present invention provides a vibration detection sensor for liquid detection based on the vibration principle.

[0007] Another object of the present invention is to provide an application of the vibration detection sensor for liquid detection based on the vibration principle.

[0008] The present invention is achieved by the following technical solutions:

[0009] A vibration detection sensor for liquid detection based on the vibration principle, comprising a columnar insulator, at least two metal conductors with different heights arranged on the surface of the columnar insulator, and pins arranged on the columnar insulator for connecting with the metal conductors; the metal conductors with different heights are not connected to each other; the pins are respectively connected to the metal conductors with different heights.

[0010] Furthermore, different potential circuits are respectively connected between one of the metal conductors on the columnar insulator and the metal conductors with different heights.

[0011] Preferably, one of the metal conductors is connected to a high-level I / O port through a pin, and the remaining metal conductors are scanned for the level state by a microcontroller; preferably, one of the metal conductors is grounded through a pin, and the remaining metal conductors are scanned for the level state by a microcontroller.

[0012] Since the molecular gaps of liquids and solids are different, the molecular gaps in the liquid change to a certain extent, which has a great impact on its own natural frequency. And since the occurrence of liquid resonance only requires an external excitation with the same resonance frequency as it, an obvious vibration phenomenon can be generated.

[0013] The vibration detection sensor of the present invention utilizes the conductivity of the liquid itself. When resonance occurs, the vibrating liquid forms a conductive path between the metal conductors with different heights, is connected to the detection circuit through the pins, and the signals output by different metal conductors are detected, so as to reflect the change of the liquid resonance amplitude and the resonance frequency, and to master the change process of the physical and chemical properties of the liquid.

[0014] Furthermore, the pins are arranged at the bottom of the columnar insulator; the distance between the pins and the adjacent metal conductors is greater than the thickness of the circuit board.

[0015] Furthermore, the number of heights at which the metal conductors are arranged is 2n (n≥1), the number of pins is at least the same as the number of heights, and they are symmetrically arranged on both sides of the bottom of the columnar insulator.

[0016] Furthermore, the number of both the metal conductors and the pins is 2n, and the pins are symmetrically arranged with n pins on each side at the bottom of the columnar insulator.

[0017] Furthermore, the metal conductors are strip-shaped and are embedded around the columnar insulator in a ring, and the metal conductors are arranged in parallel at equal intervals.

[0018] Furthermore, through holes are provided on the columnar insulator, and the metal conductors are connected to the pins through the through holes and wires.

[0019] Furthermore, small holes are provided on the columnar insulator, and the wires pass through the small holes to connect the metal conductors and the pins.

[0020] Furthermore, the columnar insulator is cylindrical, and its interior is filled with an insulating material.

[0021] Furthermore, the columnar insulator and the metal conductor are made of materials that do not chemically react with the liquid.

[0022] An application of the vibration detection sensor for liquid detection based on the vibration principle, where the vibration detection sensor cooperates with an excitation oscillator to detect changes in the physical and chemical properties of the liquid. The detection area on the excitation oscillation circuit board encloses to form a sample cell, and the columnar insulator of the vibration detection sensor cooperates with the via hole.

[0023] Furthermore, the front side of the excitation oscillation circuit board is provided with at least two circuits arranged in parallel in the detection area and having the same current direction; the circuit board is provided with a via hole at the end of the front circuit to connect to the circuit on the back side; a via hole adapted to the vibration detection sensor is provided at the center of the detection area.

[0024] Furthermore, the front side and the back side of the circuit board are coated with an insulating material; the via hole is filled and coated with an insulating material.

[0025] Furthermore, a pad is provided in the edge area of the via hole adapted to the vibration detection sensor, and the pad is parallel to the circuit on the back side.

[0026] Furthermore, the number of pads is the same as the number of pins of the vibration detection sensor.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The vibration detection sensor for liquid detection based on the vibration principle of the present invention has an innovative structural design. By setting metal conductors at different heights and utilizing the conductivity of the liquid; when resonance occurs, the vibrating liquid forms a conductive path between the metal conductors at different heights, and is connected to the detection circuit through the pins to detect the signals output by different metal conductors, thereby reflecting the resonance amplitude of the liquid and the changes in the resonance frequency, so as to master the change process of the physical and chemical properties of the liquid. The vibration detection sensor of the present invention has a simple structure, is easy to manufacture, has high precision and good repeatability. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is the bottom view of the vibration detection sensor in a specific embodiment of the present invention;

[0030] Figure 2 It is the front view of the vibration detection sensor in a specific embodiment of the present invention;

[0031] Figure 3 It is the cross-sectional view of the vibration detection sensor in a specific embodiment of the present invention;

[0032] Figure 4 Structural diagram of the excitation oscillation circuit in a specific embodiment of the present invention;

[0033] Figure 5 Back view of the excitation oscillation circuit in a specific embodiment of the present invention;

[0034] Figure 6 Front view of the excitation oscillation circuit in a specific embodiment of the present invention. Specific implementation manners

[0035] The following examples are given to specifically describe the present invention, but are not limited thereto. The raw materials used in the examples and application examples are all commercially available.

[0036] Example 1

[0037] A vibration detection sensor for liquid detection based on the vibration principle includes a columnar insulator 302, 8 metal conductors 301 embedded on the surface of the columnar insulator 302, and pins 303 located at the bottom of the columnar insulator 302 for connecting to the metal conductors 301.

[0038] The metal conductors 301 horizontally surround the columnar insulator 302, and the metal conductors 301 are arranged in parallel and do not connect to each other; the pins 303 are respectively connected to the metal conductors 301 in one-to-one correspondence.

[0039] The lowermost metal conductor 301 on the columnar insulator 302 is connected to the high-level I / O port through the pin 303, and the remaining metal conductors are scanned for the level state by the STM32F103RBT6 microcontroller. The STM32F103RBT6 microcontroller continuously reads the I / O port states corresponding to the upper 7 conductors of the vibration detector.

[0040] Since the molecular gaps of liquids and solids are different, a certain change occurs in the molecular gap in the liquid, which has a greater impact on its own natural frequency. And since the occurrence of liquid resonance only requires an external excitation with the same resonance frequency as itself, an obvious vibration phenomenon can be generated.

[0041] This vibration detection sensor utilizes the conductivity of the liquid itself. When resonance occurs, the vibrating liquid forms a conductive path between the metal conductors 301 at different heights, and is connected to the detection circuit through the pin 303. The signals output by different metal conductors are detected, and then the liquid resonance amplitude and the change in resonance frequency are reflected to master the change process of the physical and chemical properties of the liquid.

[0042] The distance between the pin 303 and the lowermost metal conductor 301 on the columnar insulator 302 is greater than the thickness of the circuit board.

[0043] The metal conductors 301 located in the upper part of the columnar insulator 302 are arranged in parallel at equal intervals.

[0044] A via hole 305 is provided on the columnar insulator 302, and the metal conductor 301 is connected to the pin 303 through the via hole 305 and a wire.

[0045] Alternatively, a small hole 305 is provided on the columnar insulator 302, and a wire passes through the small hole to connect the metal conductor 301 and the pin 303.

[0046] The via hole or small hole in the columnar insulator 302 is filled with an insulating material.

[0047] The columnar insulator 302 and the metal conductor 301 are made of materials that do not chemically react with the liquid.

[0048] The number of both the metal conductor 301 and the pins 303 is 8, and the pins 303 are symmetrically arranged with 4 pins 303 on each side at the bottom of the columnar insulator 302.

[0049] An application of a vibration detection sensor for liquid detection based on the vibration principle. The vibration detection sensor is used in cooperation with an excitation oscillation circuit to detect changes in the physical and chemical properties of a liquid. A plastic transparent cylinder is installed in a circular area 506 on the circuit board of the excitation oscillation circuit to form a sample cell, and the columnar insulator 302 of the vibration detection sensor is matched with the via hole 502 on the circuit board.

[0050] The input of the excitation oscillation circuit is one end of a 50Ω resistor, and the other end of the resistor is connected to the output of the OPA847 high-bandwidth operational amplifier.

[0051] There are 13 circuits arranged in parallel in a circular area 506 on the front of the circuit board of the excitation oscillation circuit and with the same current direction; via holes 505 are provided at the ends of the front circuits on the circuit board to connect the circuits on the back; a via hole 502 adapted to the vibration detection sensor is provided at the center of the circular area 506.

[0052] Insulating materials are applied to the front and back of the circuit board; the via holes 502 and 505 are filled and coated with insulating materials.

[0053] A pad 507 is provided in the edge area of the via hole 502 adapted to the vibration detection sensor, and the pad 507 is parallel to the circuits on the back. The number of pads 507 is the same as the number of pins 303 of the vibration detection sensor.

[0054] The liquid detection device is also provided with a temperature control module; to control the temperature of the detection environment of the liquid to be measured.

[0055] The AD9854 chip is prone to heat generation, so a heat sink is provided on the AD9854 chip.

[0056] The sample cell is equipped with a lid. After the liquid to be tested is injected into the sample cell, the plastic soft cover above the sample cell is closed to provide a relatively stable detection environment for the liquid.

[0057] Application Example 1

[0058] Place the blood to be tested in the sample cell. After the blood is injected into the sample cell, close the plastic soft cover above the sample cell to provide a relatively stable detection environment for the blood. The highest point of the blood to be tested should be level with the top of the second insulator. If the blood vibrates, due to the conductivity of the blood, the state of one or more of the other 7 I / Os will change from low level to high level. When the STM32F103RBT6 microcontroller receives the I / O state change signal, it means that the microcontroller controls the AD9854 type DDS chip to emit a frequency equal to the resonant frequency of the blood at this time.

[0059] Inject the blood to be tested into the sample cell and turn on the detection system. Command the STM32F103RBT6 microcontroller to continuously read the I / O state corresponding to the upper 7 metal conductors 301 of the vibration detector. The STM32F103RBT6 microcontroller controls the AD9854 type DDS chip to perform fast frequency sweeping by adding or subtracting variables. The variable is the excitation square wave frequency value when the blood resonates. After the frequency sweeping signal is amplified by the OPA847 high-bandwidth operational amplifier, the signal is transmitted into the excitation oscillation circuit through a resistor. Since this circuit is composed of multiple circuits arranged in parallel with the same current direction, the magnetic field generated by the current in this circuit is further strengthened.

[0060] At this time, due to the action of the alternating magnetic field, the blood will resonate when the magnetic field emits an alternating magnetic field with the same frequency as its natural frequency. When the vibration detection sensor receives the blood oscillation signal, the STM32F103RBT6 microcontroller stops frequency sweeping and writes the variable value at this time into the internal flash. Then, every 2S, the STM32F103RBT6 microcontroller controls the AD9854 type DDS chip to perform frequency sweeping again. Similarly, when the sensor receives the blood vibration signal, the STM32F103RBT6 microcontroller stops frequency sweeping and compares the variable with the variable 2S ago. If the difference between the two is greater than the threshold set by the system, it means that the blood has not coagulated yet, and the microcontroller continues to perform operations such as frequency sweeping, data recording, and data comparison until the difference between the variables separated by 2S is less than or equal to the threshold set by the system, and then the system stops frequency sweeping, indicating that the detection process is completed.

[0061] The larger the threshold value is, the less accurate the detection result will be. If the threshold value is too small, it will cause overfitting of the data. Therefore, the threshold value is very important. After the detection is completed, the STM32F103RBT6 microcontroller extracts various data of healthy blood coagulation in the EEPROM and compares them with the data of this detection. If the coagulation time of the tested blood is basically the same as that of the healthy blood, it means that the tested blood is basically normal. If the coagulation time of the tested blood is much longer or much shorter than that of the healthy blood, it means that the coagulation process of the tested blood is abnormal. The detector can also export the data of this detection through the USB interface for manual data analysis.

Claims

1. A vibration detection device for liquid detection based on the vibration principle, characterized in that, The vibration detection device includes a vibration detection sensor and an excitation oscillator; The vibration detection sensor includes a columnar insulator, a plurality of metal conductors with different heights arranged on the surface of the columnar insulator, and pins arranged on the columnar insulator for connecting with the metal conductors; The metal conductors with different heights are not connected to each other; the pins are respectively connected to the metal conductors with different heights; The metal conductors are strip-shaped and are embedded around the columnar insulator in a surrounding manner, and the metal conductors are arranged side by side at equal intervals; the bottommost metal conductor on the columnar insulator is connected to a high-level I / O port through a pin, and the remaining multiple metal conductors are scanned for the level state by a microcontroller; The vibration detection sensor and the excitation oscillator cooperate to detect changes in the physical and chemical properties of the liquid; the detection area on the excitation oscillation circuit board encloses to form a sample cell, and the columnar insulator of the vibration detection sensor cooperates with the via hole; There are at least 2 circuits arranged in parallel in the detection area on the front side of the excitation oscillation circuit board and with the same current direction; the circuit board is provided with a via hole at the end of the front-side circuit to connect the circuit on the back side; a via hole adapted to the vibration detection sensor is provided at the center of the detection area.

2. The vibration detection device for liquid detection based on the vibration principle according to claim 1, characterized in that, The pins are arranged at the bottom of the columnar insulator; the distance between the pins and the adjacent metal conductors is greater than the thickness of the circuit board.

3. The vibration detection device for liquid detection based on the vibration principle according to claim 2, characterized in that, The number of heights at which the metal conductors are arranged is 2n, and the number of pins is at least the same as the number of heights, and they are symmetrically arranged on both sides of the bottom of the columnar insulator.

4. The vibration detection device for liquid detection based on the vibration principle according to claim 1, characterized in that The columnar insulator is provided with via holes, and the metal conductors are connected to the pins through the via holes and wires.

5. The vibration detection device for liquid detection based on the vibration principle according to claim 2, wherein, The columnar insulator is provided with small holes, and the wires pass through the small holes to connect the metal conductors and the pins.

6. The vibration detection device for liquid detection based on the vibration principle according to claim 1, characterized in that, The columnar insulator is cylindrical, and the via holes are filled with insulating materials.

7. The vibration detection device for liquid detection based on the vibration principle according to claim 1, characterized in that, The columnar insulator and the metal conductor are made of materials that do not chemically react with the liquid.

8. Use of the vibration detection device for liquid detection based on the vibration principle according to any one of claims 1 to 7, characterized in that The vibration detection sensor and the excitation oscillator cooperate to detect changes in the physical and chemical properties of the liquid.

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