Vibration device for fetal heart simulation
By using speakers to drive the vertical vibration of the targeted ball in the fetal heart simulator, the disordered vibration problem of the magnetic targeted ball in the changing magnetic field is solved, and the consistency and linear adjustment of the vibration amplitude are achieved.
Patent Information
- Application Number
- CN202421440958.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-24
- Publication Date
- 2025-05-16
- Estimated Expiration
- 2034-06-24
AI Technical Summary
In the existing fetal heart simulator, the magnetic targeted ball is prone to cause disordered vibrations in the non-vertical direction, and the vibration amplitude is difficult to ensure consistency under the action of inertia and gravity.
A vibrating device including a human-computer interaction module, a main control module, a D/A conversion circuit, a power amplifier circuit, a speaker and a power supply module is adopted. The target ball is driven to move up and down in the degassed water through the diaphragm of the speaker to achieve vertical vibration, and the vibration amplitude is linearly adjusted through the power amplifier circuit.
The vertical vibration of the target ball is achieved with good consistency of vibration amplitude, which overcomes the disordered vibration of the traditional magnetic target ball in the changing magnetic field, and can linearly adjust the vibration amplitude.
Smart Images
Figure CN222870534U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of fetal heart detection, in particular to a vibration device for fetal heart simulation. Background Art
[0002] Fetal heart rate monitoring is one of the main methods of perinatal health monitoring and is widely used in clinical practice. Ultrasonic Doppler fetal monitors and fetal heart monitors are a type of product that is widely used in the field of obstetrics and gynecology. They transmit ultrasonic waves to the fetal heart tissue and demodulate the generated ultrasonic echoes to obtain the ultrasonic Doppler frequency shift signal generated by the fetal heart movement. After calculation and analysis, real-time heart rate data is obtained to reflect the health status of the fetal heart function. The application of fetal heart monitoring technology can reduce the incidence of fetal intrauterine distress, fetal brain damage, neonatal asphyxia and death, improve the quality of maternal and child health care in the perinatal period, and reduce pregnancy risks. Standards and technical specifications such as YY / T 0448-2019 Ultrasonic Doppler Fetal Heart Rate Monitor, YY / T 0449-2018 Ultrasonic Doppler Fetal Monitor, YY / T 0749-2009 Ultrasonic Handheld Probe Doppler Fetal Heart Rate Detector Performance Requirements and Measurement and Reporting Methods, and JJG 893-2007 Ultrasonic Doppler Fetal Heart Rate Monitor Ultrasonic Source Calibration Procedure all put forward requirements for the quality and accuracy of fetal heart rate monitors. The quality evaluation of fetal heart rate monitors is mainly carried out through fetal heart simulators, and the indicators include fetal heart rate accuracy, detection depth, sensitivity, etc. At present, one of the technical routes adopted by fetal heart simulators is to drive the magnetic targeting ball to vibrate back and forth by changing the direction of the magnetic field by controlling the coil current. However, the inventors of this application have found that this method has the following problems after research: first, the magnetic targeting ball is prone to disordered vibration in non-vertical directions, and second, it is difficult to ensure the consistency of the vibration amplitude of the magnetic targeting ball under the action of inertia and gravity. Utility Model Content
[0003] In view of the technical problems that the magnetic targeting ball is prone to disordered vibration in non-vertical directions and the vibration amplitude of the magnetic targeting ball is difficult to ensure consistency under the action of inertia and gravity in the existing method of using control coil current to change the direction of the magnetic field to drive the magnetic targeting ball to vibrate back and forth, the utility model provides a vibration device for fetal heart simulation.
[0004] In order to solve the above technical problems, the utility model adopts the following technical solutions:
[0005] A vibration device for fetal heart simulation comprises a human-computer interaction module, a main control module, a D / A conversion circuit, a power amplifier circuit, a loudspeaker and a power supply module. The human-computer interaction module is connected to the main control module for realizing the setting of fetal heart rate and heartbeat intensity parameters or the selection and data display of typical fetal heart rate waveforms. The main control module outputs a digital current signal according to the parameters set by the human-computer interaction module or the selected waveform. The D / A conversion circuit is connected to the main control module for converting the digital current signal into an analog current signal and then forming a bipolar voltage signal through an operational amplifier. The power amplifier circuit is connected to the D / A conversion circuit for linearly regulating the bipolar voltage signal and then amplifying it through a power amplifier to generate a voltage sufficient to drive the loudspeaker to vibrate. The loudspeaker is connected to the power amplifier circuit for vibrating according to the amplified voltage. The power supply module is connected to the main control module for providing power.
[0006] Furthermore, the D / A conversion circuit includes a D / A conversion chip that converts a digital current signal into an analog current signal, a first operational amplifier that converts the analog current signal into an analog voltage signal, and a second operational amplifier that converts the analog voltage signal into a bipolar voltage signal.
[0007] Furthermore, the power amplifier circuit includes a potentiometer for linearly adjusting the bipolar voltage signal, a power amplifier capacitor for filtering the linearly adjusted bipolar voltage signal, and a power amplifier for amplifying the filtered bipolar voltage signal to generate a voltage sufficient to drive the speaker to vibrate.
[0008] Furthermore, the first fixed end of the potentiometer is connected to the output end of the D / A conversion circuit, the second fixed end of the potentiometer is grounded, and the movable end of the potentiometer is connected to the input end of the power amplifier via the power amplifier capacitor.
[0009] Furthermore, the diaphragm of the speaker is made of expanded polytetrafluoroethylene material, and the surface of the expanded polytetrafluoroethylene material is coated with sound-absorbing material.
[0010] Compared with the prior art, the vibration device for fetal heart simulation provided by the utility model sets the fetal heart rate and heartbeat intensity parameters or selects a typical fetal heart rate waveform and displays the parameter waveform through the human-computer interaction module. The main control module outputs a digital current signal according to the parameters set by the human-computer interaction module or the selected waveform. The D / A conversion circuit converts the digital current signal into an analog current signal and then forms a bipolar voltage signal through an operational amplifier. The power amplifier circuit linearly adjusts the bipolar voltage signal and then amplifies it through a power amplifier to generate a voltage sufficient to drive the speaker to vibrate. The speaker vibrates according to the amplified voltage, and then the diaphragm vibration of the speaker drives the target ball to move up and down in the degassed water, thereby simulating the fetal heartbeat. In this device, the speaker structure is used to cleverly realize the vertical vibration of the target ball up and down. The elasticity of the diaphragm of the speaker makes the vibration amplitude of the target ball more consistent, overcoming the disordered vibration of the traditional magnetic target ball in a changing magnetic field; the vibration amplitude of the target ball is related to the vibration intensity of the diaphragm of the speaker, so the vibration amplitude can be linearly adjusted through the power amplifier circuit. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Figure 1 The utility model provides a principle block diagram of a vibration device for fetal heart simulation.
[0012] Figure 2 yes Figure 1 Schematic diagram of the D / A conversion circuit.
[0013] Figure 3 yes Figure 1 Circuit diagram of medium power amplifier circuit.
[0014] In the figure, 1. Human-computer interaction module; 2. Main control module; 3. D / A conversion circuit; 4. Power amplifier circuit; 5. Speaker; 6. Power supply module. DETAILED DESCRIPTION
[0015] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described below with reference to specific illustrations.
[0016] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0017] Please refer to Figure 1As shown, the utility model provides a vibration device for fetal heart simulation, including a human-computer interaction module 1, a main control module 2, a D / A conversion circuit 3, a power amplifier circuit 4, a speaker 5 and a power module 6. The human-computer interaction module 1 is connected to the main control module 2 to realize the setting of fetal heart rate and heartbeat intensity parameters or the selection and data display of typical fetal heart rate waveforms, that is, the human-computer interaction module 1 is used to realize parameter setting or waveform selection and data display, and can realize input data setting by setting fetal heart rate and heartbeat intensity parameters or selecting built-in existing typical fetal heart rate waveforms. The human-computer interaction module 1 can specifically adopt existing The main control module 2 outputs a digital current signal according to the parameters set by the human-computer interaction module 1 or the selected waveform. The D / A conversion circuit 3 is connected to the main control module 2 to convert the digital current signal into an analog current signal and then form a bipolar voltage signal through an operational amplifier. The power amplifier circuit 4 is connected to the D / A conversion circuit 3 to linearly adjust the bipolar voltage signal and then amplify it through a power amplifier to generate a voltage sufficient to drive the speaker to vibrate. The speaker 5 is connected to the power amplifier circuit 4 to vibrate according to the amplified voltage. The power module 6 is connected to the main control module 1 to provide power. Among them, the main control module 2 controls the device as a whole, which can be implemented by using an existing chip with the model STM32L053. The chip is an ultra-low power 32-bit microcontroller that integrates a memory protection unit, a high-speed embedded memory, and various enhanced I / O and peripheral resources. It controls the D / A conversion circuit to generate a voltage signal waveform.
[0018] As a specific example, please refer to Figure 2 As shown, the D / A conversion circuit 3 includes a D / A conversion chip that converts a digital current signal into an analog current signal, a first operational amplifier OA1 that converts an analog current signal into an analog voltage signal, and a second operational amplifier OA2 that converts an analog voltage signal into a bipolar voltage signal. Specifically, the D / A conversion chip uses an integrated chip of model DAC0832, which is composed of an 8-bit input latch, an 8-bit DAC register, an 8-bit D / A conversion circuit and a conversion control circuit. It is connected to the main control module STM32L053 chip using a secondary buffer connection method to achieve synchronous output; the analog current output by the integrated chip is proportional to the input digital current (D0-D7). Since the output is a current signal, it must be converted into a voltage signal through an external operational amplifier, namely the first operational amplifier OA1. At the same time, the voltage signal is required to be bipolar, so it is necessary to connect the conversion circuit again, namely the second operational amplifier OA2, to form a power amplifier circuit front-end signal, namely a bipolar voltage signal. The output voltage range of the D / A conversion circuit 3 is -V REF ~+V REF VREF The reference voltage is set to 10V in this embodiment, and the minimum resolution of the output voltage is 10 / 2 8 ≈0.04V, V OUT is the input signal of the power amplifier circuit 4.
[0019] As a specific example, please refer to Figure 3 As shown, the power amplifier circuit 4 includes a potentiometer RP1 for linearly adjusting the bipolar voltage signal, a power amplifier capacitor C1 for filtering the bipolar voltage signal after linear adjustment, and a power amplifier for amplifying the filtered bipolar voltage signal to generate a voltage sufficient to drive the speaker 5 to vibrate. Specifically, the potentiometer RP1 is composed of a resistor and a brush that can move along the resistor. The first fixed end of the potentiometer RP1 is connected to the output end V OUT The second fixed end of the potentiometer RP1 is grounded, and the movable end of the potentiometer RP1 is connected to the input end of the power amplifier through the power amplifier capacitor C1. When the brush moves along the resistor, a voltage proportional to the displacement can be obtained at the output end, thereby linearly adjusting the voltage before entering the power amplifier. The value of the power amplifier capacitor C1 is 10uF. In addition to the basic characteristics of isolating DC and passing AC, it can also resist electromagnetic interference and interference caused by power changes over time, suppress additional noise and clutter, and improve the accuracy of audio signals. At the same time, it can also play a role in stabilizing voltage distribution, thereby effectively protecting the power amplifier circuit. The power amplifier can be specifically implemented using an existing LM386 audio integrated amplifier, and the voltage gain of the integrated amplifier can be adjusted in the range of 20 to 200 times; the purpose of the power amplifier is to amplify the weak voltage signal of the pre-stage operational amplifier to reach a voltage sufficient to drive the speaker, and then the diaphragm vibration of the speaker drives the target ball to move up and down in the degassed water, thereby simulating the heartbeat of the fetus.
[0020] As a specific embodiment, the speaker 5 adopts a waterproof design. Specifically, the diaphragm of the speaker 5 is made of existing expanded polytetrafluoroethylene material, which is a new type of medical polymer material with good elasticity and flexibility, and has corrosion resistance and wear resistance. Its waterproof level reaches IPX7 level; compared with the traditional speaker diaphragm, the present application also coats the surface of the diaphragm made of expanded polytetrafluoroethylene material with an ultra-thin sound-absorbing material. This material has tiny pores that can allow air circulation (to achieve the functions of heat dissipation and pressure relief), and can reduce the sound interference generated by the speaker. At the same time, the material can also effectively block moisture and dust particles. The sound-absorbing material can be specifically realized by selecting existing porous materials.
[0021] Compared with the prior art, the vibration device for fetal heart simulation provided by the utility model sets the fetal heart rate and heartbeat intensity parameters or selects a typical fetal heart rate waveform and displays the parameter waveform through the human-computer interaction module. The main control module outputs a digital current signal according to the parameters set by the human-computer interaction module or the selected waveform. The D / A conversion circuit converts the digital current signal into an analog current signal and then forms a bipolar voltage signal through an operational amplifier. The power amplifier circuit linearly adjusts the bipolar voltage signal and then amplifies it through a power amplifier to generate a voltage sufficient to drive the speaker to vibrate. The speaker vibrates according to the amplified voltage, and then the diaphragm vibration of the speaker drives the target ball to move up and down in the degassed water, thereby simulating the fetal heartbeat. In this device, the speaker structure is used to cleverly realize the vertical vibration of the target ball up and down. The elasticity of the diaphragm of the speaker makes the vibration amplitude of the target ball more consistent, overcoming the disordered vibration of the traditional magnetic target ball in a changing magnetic field; the vibration amplitude of the target ball is related to the vibration intensity of the diaphragm of the speaker, so the vibration amplitude can be linearly adjusted through the power amplifier circuit.
[0022] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the utility model, which should be included in the scope of the claims of the utility model.
Claims
1. A vibration device for fetal heart simulation, characterized in that: It includes a human-computer interaction module, a main control module, a D / A conversion circuit, a power amplifier circuit, a loudspeaker and a power supply module. The human-computer interaction module is connected to the main control module to realize the setting of fetal heart rate and heartbeat intensity parameters or the selection and data display of typical fetal heart rate waveforms. The main control module outputs a digital current signal according to the parameters set by the human-computer interaction module or the selected waveform. The D / A conversion circuit is connected to the main control module to convert the digital current signal into an analog current signal and then form a bipolar voltage signal through an operational amplifier. The power amplifier circuit is connected to the D / A conversion circuit to linearly adjust the bipolar voltage signal and then amplify it through a power amplifier to generate a voltage sufficient to drive the loudspeaker to vibrate. The loudspeaker is connected to the power amplifier circuit to vibrate according to the amplified voltage. The power supply module is connected to the main control module to provide power.
2. The vibration device for fetal heart simulation according to claim 1, characterized in that: The D / A conversion circuit includes a D / A conversion chip for converting a digital current signal into an analog current signal, a first operational amplifier for converting the analog current signal into an analog voltage signal, and a second operational amplifier for converting the analog voltage signal into a bipolar voltage signal.
3. The vibration device for fetal heart simulation according to claim 1, characterized in that: The power amplifier circuit includes a potentiometer for linearly adjusting a bipolar voltage signal, a power amplifier capacitor for filtering the linearly adjusted bipolar voltage signal, and a power amplifier for amplifying the filtered bipolar voltage signal to generate a voltage sufficient to drive the speaker to vibrate.
4. The vibration device for fetal heart simulation according to claim 3, characterized in that: The first fixed end of the potentiometer is connected to the output end of the D / A conversion circuit, the second fixed end of the potentiometer is grounded, and the movable end of the potentiometer is connected to the input end of the power amplifier via the power amplifier capacitor.
5. The vibration device for fetal heart simulation according to claim 1, characterized in that: The diaphragm of the loudspeaker is made of expanded polytetrafluoroethylene material, and the surface of the expanded polytetrafluoroethylene material is coated with sound-absorbing material.