Thoracico-abdominal respiratory movement sensor

Abstract

The utility model relates to a thoracico-abdominal breathing motion sensor, which belongs to the technical field of medical monitoring, and comprises a piezoelectric sensing device, an analysis circuit, a signal processing circuit, a signal processing circuit, a signal processing circuit, a signal processing circuit, a signal processing circuit, a signal processing circuit and a signal processing circuit, and the piezoelectric sensing device is used for collecting thoracico-abdominal motion when a patient breathes, converting the thoracico-abdominal motion into voltage signals and inputting the voltage signals into the analysis circuit; the analysis circuit is used for receiving the voltage signal, converting the voltage signal into a respiratory movement signal and transmitting the respiratory movement signal to a display device; and the display device is used for displaying a breathing movement waveform based on the breathing movement signal. The thoracico-abdominal respiratory movement sensor provided by the utility model is not influenced by environmental factors when being used for monitoring respiratory movement of a patient, is convenient to use and can accurately monitor the respiratory movement.

Description

Technical Field

[0001] This utility model relates to the field of medical monitoring technology, and in particular to a chest and abdominal respiratory motion sensor. Background Technology

[0002] With the continuous development of medical technology and the increasing attention people pay to health, there are more and more medical monitoring programs for patients.

[0003] For some patients, it is necessary to monitor their breathing. Among the existing respiratory monitoring methods, there are mainly thermal and pressure types. Thermal monitoring monitors respiratory movements by checking the temperature of exhaled air, while pressure monitoring monitors respiratory movements by detecting the pressure of exhaled air. However, both of these methods are greatly affected by environmental interference, have complex structures, and are inconvenient to use.

[0004] It is evident that current technologies for monitoring patients' respiratory movements are significantly affected by environmental factors and are inconvenient to use. Utility Model Content

[0005] In view of this, it is necessary to provide a chest and abdominal respiratory motion sensor to solve the problem that the monitoring of patients' respiratory movements in the existing technology is greatly affected by the environment and is inconvenient to use.

[0006] To address the above problems, this utility model provides a chest and abdominal respiratory motion sensor, comprising:

[0007] A piezoelectric sensing device is used to collect the chest and abdominal movements of a patient during breathing, convert the chest and abdominal movements into voltage signals, and input the voltage signals to an analysis circuit.

[0008] The analysis circuit is used to receive the voltage signal, convert the voltage signal into a respiratory motion signal, and transmit the respiratory motion signal to the display device;

[0009] The display device is used to display the respiratory motion waveform based on the respiratory motion signal.

[0010] In one possible implementation, the piezoelectric sensing device is a piezoelectric ceramic sheet.

[0011] In one possible implementation, the piezoelectric ceramic sheet has a diameter of 20 mm.

[0012] In one possible implementation, the analysis circuit includes:

[0013] Two voltage signal terminals are connected in parallel with capacitors C1 and C2. The first end of capacitor C2 is connected to the first end of resistor R1, and the second end of capacitor C2 is connected to the first end of capacitor R2. The second end of resistor R1 is connected to the first end of resistor R3 and the first end of capacitor C3. The second end of resistor R2 is connected to the second end of resistor R3 and the second end of capacitor C3. The second end of capacitor C3 is grounded. The first end of capacitor C3 is connected to the first end of resistor R6 via capacitor C6. The first end of resistor R6 is connected to the negative input terminal of an operational amplifier. The positive input terminal of the operational amplifier is connected to the first end of resistor R4 and the second end of resistor R5. The second end of resistor R4 is connected to the DC input. A capacitor C4 is connected in parallel across the two ends of resistor R5. The second end of resistor R5 is grounded. A resistor R7 and a capacitor C5 are connected in parallel between the negative input terminal and the output terminal of the operational amplifier. The output terminal of the operational amplifier is connected to the signal output terminal, and the output terminal of the operational amplifier is grounded via resistor R8 and capacitor C7.

[0014] In one possible implementation, the capacitance of capacitors C1, C2, and C6 is 1uF, and the resistors R1, R2, and R3, along with capacitor C3, satisfy the following formula:

[0015]

[0016] Where f is the frequency of the input voltage, c is the capacitance of capacitor C3, R1=R2, and R3=0.2(R1+R3), R7=10R6, R4=R5, R8=100Ω, and C7=22pF.

[0017] In one possible implementation, the operational amplifier is model AD8607.

[0018] In one possible implementation, it also includes:

[0019] A fixed block is provided, on one side of which the piezoelectric sensing device is fixedly installed. The fixed block is snapped into the inner wall of the outer shell cavity. A column is provided on the other side of the fixed block. The column is fixedly connected to a rope. A through groove is provided on the fixed block and the outer shell. The rope is connected to a strap through the through groove. The strap is used to bind the chest and abdominal respiratory motion sensor to the patient's chest.

[0020] In one possible implementation, the strap is an elastic strap.

[0021] In one possible implementation, the display device is an oscilloscope.

[0022] In one possible implementation, the fixing block is a plastic fixing block, and the outer shell is a plastic outer shell.

[0023] The beneficial effects of this utility model are as follows: The chest and abdominal respiratory motion sensor provided by this utility model collects chest and abdominal motion information of the patient during breathing through a piezoelectric sensing device, converts the chest and abdominal motion information into a voltage signal, analyzes the voltage signal through an analysis circuit to obtain the patient's respiratory motion signal, and displays the respiratory motion signal. When monitoring the patient's respiratory motion, it is not affected by environmental factors, is convenient to use, and provides accurate monitoring of respiratory motion. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 is a schematic diagram of a chest and abdominal respiratory motion sensor provided by this utility model;

[0026] Figure 2 A circuit diagram of an analysis circuit provided by this utility model;

[0027] Figure 3 A waveform diagram of the voltage signal before filtering provided by this utility model;

[0028] Figure 4 A filtered voltage signal waveform diagram provided by this utility model;

[0029] Figure 5 A structural diagram of a chest and abdominal respiratory motion sensor provided by this utility model;

[0030] Among them, 1-piezoelectric sensing device, 2-fixed block, 3-column, 4-rope, 5-shell. Detailed Implementation

[0031] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0032] The terms "first," "second," etc., used in the embodiments of this utility model are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a technical feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature.

[0033] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the present invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0034] A specific embodiment of this utility model is as follows: Figure 1 As shown, a chest and abdominal respiratory motion sensor is disclosed, comprising:

[0035] The piezoelectric sensing device 101 is used to collect the chest and abdominal movements of the patient during breathing, convert the chest and abdominal movements into voltage signals, and input the voltage signals to the analysis circuit.

[0036] Analysis circuit 102 is used to receive voltage signals, convert voltage signals into respiratory motion signals, and transmit respiratory motion signals to display devices;

[0037] Display device 103 is used to display respiratory motion waveforms based on respiratory motion signals.

[0038] In this embodiment of the invention, the piezoelectric sensing device may be a piezoelectric ceramic sheet. The piezoelectric ceramic sheet is in contact with the patient's chest. When the patient performs breathing movements that cause the chest or abdominal cavity to expand outward, the piezoelectric ceramic sheet will deform. When the piezoelectric ceramic sheet is deformed, it will generate a piezoelectric effect and generate a voltage. Optionally, the diameter of the piezoelectric ceramic sheet is 20 mm.

[0039] Furthermore, such as Figure 2 As shown, the analysis circuit 102 includes:

[0040] Two voltage signal terminals IN1 and IN2 are connected in parallel with capacitors C1 and C2. The first end of capacitor C2 is connected to the first end of resistor R1, and the second end of capacitor C2 is connected to the first end of capacitor R2. The second end of resistor R1 is connected to the first end of resistor R3 and the first end of capacitor C3. The second end of resistor R2 is connected to the second end of resistor R3 and the second end of capacitor C3. The second end of capacitor C3 is grounded. The first end of capacitor C3 is connected to the first end of resistor R6 via capacitor C6. The first end of resistor R6 is connected to the negative input terminal of the operational amplifier. The positive input terminal of the operational amplifier is connected to the first end of resistor R4 and the second end of resistor R5. The second end of resistor R4 is connected to the DC input. A capacitor C4 is connected in parallel across the two ends of resistor R5. The second end of resistor R5 is grounded. A resistor R7 and a capacitor C5 are connected in parallel between the negative input terminal and the output terminal of the operational amplifier. The output terminal of the operational amplifier is connected to the signal output terminal OUT, and the output terminal of the operational amplifier is grounded through resistor R8 and capacitor C7.

[0041] In this embodiment of the invention, the working principle of the analysis circuit is as follows: Since the piezoelectric element is in an open-circuit state when not subjected to external force, its impedance is extremely high, typically in the hundreds of MΩ range. When subjected to external force and exhibiting a piezoelectric effect, the impedance decreases, but remains at tens of MΩ, exhibiting capacitive behavior overall. The output voltage is essentially charge; therefore, a capacitor needs to be connected in parallel to collect the charge and improve the frequency characteristics. Based on the characteristics of the piezoelectric ceramic sheet, capacitors C1=C2=1uF are selected. When the patient performs respiratory movements, the chest and abdominal movements cause noise in the signal waveform output by the piezoelectric ceramic sheet. Figure 3 As shown, the output waveform is not smooth enough, so a low-pass filter is needed to form a low-pass filter with R1, R2, R3, and C3 to filter the output signal of the piezoelectric ceramic sheet. The resistors R1, R2, R3, and capacitor C3 satisfy the following formula:

[0042]

[0043] Where f is the frequency of the input voltage and c is the capacitance of capacitor C3.

[0044] The voltage signal output by the piezoelectric ceramic sheet is passed through this low-pass filter to obtain the following result: Figure 4 The voltage signal shown is further amplified by an operational amplifier. The operational amplifier can be an AD8607 precision operational amplifier, which features low power consumption, low noise, and high input impedance, making it suitable for sensor signal conditioning applications. The amplification factor of the operational amplifier depends on the relationship between resistors R6 and R7. In this embodiment, R7 = 10R6, so the amplification factor of the operational amplifier is 10 times, meaning the voltage signal output from the filtered piezoelectric ceramic sheet can be amplified 10 times and displayed on an oscilloscope. Further, C6 is a DC blocking capacitor, with C6 = 1uF, and R4 = R5, providing DC bias voltage for the operational amplifier. C4 is a bypass capacitor, stabilizing the DC bias voltage. C5 is a feedback capacitor, improving the frequency characteristics of the operational amplifier. R8 and C7 are configured as output impedance resistors, with R8 = 100Ω and C7 = 22pF. In this embodiment, the selection of each component can be determined according to actual conditions.

[0045] As one possible embodiment of this utility model, in this embodiment, such as Figure 5As shown, the chest and abdominal respiratory motion sensor includes a fixing block 2, a piezoelectric sensing device 1 fixedly installed on one side of the fixing block 2, the fixing block 2 snapped into the inner wall of the outer shell cavity 5, a column 3 is provided on the other side of the fixing block 2, the column 3 is fixedly connected to the rope 4, the fixing block 2 and the outer shell 5 are provided with through grooves, the rope 4 is connected to the binding strap through the through grooves, and the binding strap is used to bind the chest and abdominal respiratory motion sensor to the patient's chest. In use, the chest and abdominal respiratory motion sensor is strapped to the chest or abdomen of the human body. When the human body inhales, the chest or abdomen expands outward, which causes the column to exert an outward force, thereby causing the piezoelectric ceramic plate to deform. The piezoelectric ceramic plate generates a corresponding voltage signal when it deforms. When the human body exhales, the chest or abdomen moves inward, causing the column to move inward, which causes the piezoelectric ceramic plate to return to its original shape, and the piezoelectric ceramic plate no longer outputs a voltage signal. Based on this, the piezoelectric ceramic plate will intermittently output a voltage signal when the patient inhales and exhales. The output voltage information is then processed by the analysis circuit and displayed on an oscilloscope, thus completing the patient's respiratory monitoring.

[0046] The chest and abdominal respiratory motion sensor provided by this utility model collects chest and abdominal motion information of a patient during breathing through a piezoelectric sensing device, converts this information into a voltage signal, and analyzes the voltage signal through an analysis circuit to obtain the patient's respiratory motion signal, which is then displayed. When monitoring a patient's respiratory motion, it is unaffected by environmental factors, is easy to use, and provides accurate monitoring of respiratory motion. Furthermore, the voltage signal output by the piezoelectric ceramic plate is filtered by a low-frequency filter in the analysis circuit to eliminate external influences, and the voltage signal is amplified by an operational amplifier to improve the observability of the respiratory motion signal. Moreover, the chest and abdominal respiratory motion sensor provided by this utility model can be directly fixed to the patient's chest or abdomen with an elastic strap during use, requiring no other operation and making it convenient to use.

[0047] The above are merely preferred embodiments of this utility model, but the scope of protection of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the scope of protection of this utility model.

Claims

1. A chest and abdominal respiratory motion sensor, characterized in that, include: A piezoelectric sensing device is used to collect the chest and abdominal movements of a patient during breathing, convert the chest and abdominal movements into voltage signals, and input the voltage signals to an analysis circuit. The analysis circuit is used to receive the voltage signal, convert the voltage signal into a respiratory motion signal, and transmit the respiratory motion signal to the display device; The display device is used to display the respiratory motion waveform based on the respiratory motion signal; The analysis circuit includes: Two voltage signal terminals are connected in parallel with capacitors C1 and C2. The first end of capacitor C2 is connected to the first end of resistor R1, and the second end of capacitor C2 is connected to the first end of capacitor R2. The second end of resistor R1 is connected to the first end of resistor R3 and the first end of capacitor C3. The second end of resistor R2 is connected to the second end of resistor R3 and the second end of capacitor C3. The second end of capacitor C3 is grounded. The first end of capacitor C3 is connected to the first end of resistor R6 via capacitor C6. The first end of resistor R6 is connected to the negative input terminal of an operational amplifier. The positive input terminal of the operational amplifier is connected to the first end of resistor R4 and the second end of resistor R5. The second end of resistor R4 is connected to the DC input. A capacitor C4 is connected in parallel across the two ends of resistor R5. The second end of resistor R5 is grounded. A resistor R7 and a capacitor C5 are connected in parallel between the negative input terminal and the output terminal of the operational amplifier. The output terminal of the operational amplifier is connected to the signal output terminal, and the output terminal of the operational amplifier is grounded via resistor R8 and capacitor C7.

2. The chest and abdominal respiratory motion sensor according to claim 1, characterized in that, The piezoelectric sensing device is a piezoelectric ceramic sheet.

3. The chest and abdominal respiratory motion sensor according to claim 2, characterized in that, The diameter of the piezoelectric ceramic sheet is 20 mm.

4. The chest and abdominal respiratory motion sensor according to claim 1, characterized in that, The capacitance of capacitors C1, C2, and C6 is 1uF. Resistors R1, R2, and R3, along with capacitor C3, satisfy the following formula: Where f is the frequency of the input voltage, c is the capacitance of capacitor C3, R1=R2, and R3=0.2(R1+R3), R7=10R6, R4=R5, R8=100Ω, and C7=22pF.

5. The chest and abdominal respiratory motion sensor according to claim 1, characterized in that, The operational amplifier is model AD8607.

6. The chest and abdominal respiratory motion sensor according to claim 1, characterized in that, Also includes: A fixed block is provided, on one side of which the piezoelectric sensing device is fixedly installed. The fixed block is snapped into the inner wall of the outer shell cavity. A column is provided on the other side of the fixed block. The column is fixedly connected to a rope. A through groove is provided on the fixed block and the outer shell. The rope is connected to a strap through the through groove. The strap is used to bind the chest and abdominal respiratory motion sensor to the patient's chest.

7. The chest and abdominal respiratory motion sensor according to claim 6, characterized in that, The strap is an elastic strap.

8. The chest and abdominal respiratory motion sensor according to claim 1, characterized in that, The display device is an oscilloscope.

9. The chest and abdominal respiratory motion sensor according to claim 6, characterized in that, The fixing block is a plastic fixing block, and the outer shell is a plastic outer shell.

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