Plugging device form control circuit

Abstract

The invention belongs to the technical field of esophageal fistula plugging devices, and particularly relates to a form control circuit of a plugging device. The plugging device form control circuit comprises a master control single-chip microcomputer, a drive circuit and a power supply. The driving circuit is driven by an H bridge and comprises the H bridge, a follow current compensation circuit, a driving chip and a differential detection circuit. The plugging device has the advantages that the form control capacity of the plugging device is achieved, and the problems that due to the fact that the form of an existing plugging device cannot be controlled, the position of the plugging device is difficult to adjust, the plugging effect of the plugging device is uncontrollable, the plugging device cannot conduct plugging completely, and pressure distribution of the plugging device is uneven can be well solved. According to the plugging device form control circuit in the technical scheme, the system response time is short, due to the fact that variables involved in detection and execution are simple, complex operation is not needed, the software execution efficiency is high in the process, and the system response time is a few microseconds.

Description

Technical Field

[0001] The invention belongs to the technical field of esophageal fistula occluders, and in particular relates to a morphology control circuit of an occluder. Background Art

[0002] An occluder is a medical device used for interventional treatment, mainly used to occlude defects in blood vessels or the heart, such as atrial septal defect (ASD), ventricular septal defect (VSD), patent ductus arteriosus (PDA), etc. Occluders are usually made of nickel-titanium shape memory alloy (Nitinol) or other metal materials and covered with fabric or other biocompatible materials. However, the existing occluders have the defect of uncontrollable morphology in practical applications. So far, no relevant reports have been published on technical specifications for occluder morphology control.

[0003] The defects of the occluder's morphological control ability are specifically reflected in the following aspects: 1. Lack of flexibility Insufficient adaptability: Existing occluders are often designed with fixed shapes and sizes, and once placed in the body, their shape is difficult to change. This means that the occluder may not be able to fully adapt to the subtle differences in the anatomical structure of individual patients.

[0004] Difficult position adjustment: Once the occluder is in place, it is difficult to fine-tune or reposition it if the position is not ideal or the occlusion effect is poor.

[0005] 2. Poor compatibility with different anatomical structures Individual differences: Each patient’s anatomy is different, and a fixed occluder design may not perfectly match the heart or vascular structure of all patients.

[0006] Complex structures: For some complex anatomical structures, such as irregular defect edges or abnormal vascular pathways, existing occluders may not provide adequate occlusion effects.

[0007] 3. The blocking effect is uncontrollable Incomplete occlusion: Due to the fixed shape of the occluder, the target area may not be completely occluded in some cases, leaving potential leaks.

[0008] Uneven pressure distribution: After placement, the occluder may exert uneven pressure on the surrounding tissues, causing local tissue damage or other complications.

[0009] 4. Long-term stability issues Risk of displacement: Lack of morphological control capability may cause the occluder to shift during long-term use, affecting the occlusion effect.

[0010] At present, if the occluder needs to be morphologically controlled, it is inconvenient to observe and operate it through a gastroscope when operating it in the human body. Due to the low density of the occluder itself, it is difficult to observe the fine structure of the occluder even through X-ray (CT imaging) technology. Therefore, how to control the morphology of such an occluder requires close cooperation between the occluder functional structure, control circuit, and software algorithm to achieve it. Summary of the invention

[0011] At present, in order to address the weakness of the uncontrollable shape of the occluder, it is considered to use a control rope provided on the occluder to adjust the more detailed joint parts and airbag parts of the occluder. The specific shape of the occluder cannot be observed visually during the adjustment process. The present invention considers changing the tactile feel of the rope during the process of adjusting the control rope provided on the occluder. Specifically, when the shape of the occluder is adjusted to be consistent with the shape of the fistula that the occluder needs to block, the force driving the control rope on the occluder will change, and this change process can be reflected by the current signal in the circuit, helping us to judge whether the shape of the occluder has been adjusted to a suitable structure.

[0012] To achieve the above functions, the technical solution of the present invention is as follows: Occluder morphology control circuit: including main control microcontroller, drive circuit and power supply; The driving circuit adopts H-bridge driving, and the driving circuit includes H-bridge, freewheeling compensation circuit, driving chip, differential detection circuit, H-bridge includes field effect tube Q4, field effect tube Q7, field effect tube Q2, field effect tube Q8 and motor M, wherein the drain of field effect tube Q4 and field effect tube Q2 is connected to VCC, wherein one end of motor M is arranged on the source of field effect tube Q4 and the drain of field effect tube Q7, wherein one end of motor M is arranged on the source of field effect tube Q2 and the drain of field effect tube Q8, wherein the source of field effect tube Q7 and field effect tube Q8 is connected to bias resistor, and one end of bias resistor is grounded, the freewheeling compensation circuit is used to compensate for the inductive reactance of the field effect tube of H-bridge, the input end of differential detection circuit is arranged on the source of field effect tube Q7 and the source of field effect tube Q8, and the output end of differential detection circuit is connected to the ADC port of single-chip computer.

[0013] Furthermore, one end of the differential detection circuit is connected to a detection capacitor, one end of the detection capacitor is connected to a shunt resistor, one end of the shunt resistor is grounded, the shunt resistor is connected in parallel to the non-inverting input and inverting input of the differential amplifier, and the output of the differential amplifier is connected to the ADC port of the microcontroller.

[0014] Furthermore, a protection circuit is provided at the output end of the differential amplifier, the protection circuit includes a capacitor C13 and two diodes, one end of the capacitor C13 is connected to the output end of the differential amplifier, the other end of the capacitor C13 is connected to the input end of one of the diodes and ground, the output end of the above diode is connected to the output end of the differential amplifier and the input end of another diode, and the output end of the other diode is connected to VCC3.3.

[0015] The present invention contracts the control rope on the occluder through the operation of the motor M (forward or reverse rotation), specifically through the H-bridge control, and realizes various working modes of the motor according to the connection and conduction mode of the H-bridge and the field effect tube Q4, the field effect tube Q7, the field effect tube Q2, the field effect tube Q8, and the motor M, such as forward rotation, reverse rotation, speed regulation, and braking. Forward rotation: to realize the forward rotation of the motor, it is necessary to turn on the field effect tube Q4 and the field effect tube Q8 and turn off the field effect tube Q2 and the field effect tube Q7. Reverse rotation: to realize the reverse rotation of the motor, it is necessary to turn on the field effect tube Q2, the field effect tube Q7 and turn off the field effect tube Q4 and the field effect tube Q8. Speed ​​regulation: on the premise of turning on the field effect tube Q8 and turning off the field effect tube Q2 and the field effect tube Q7, the conduction of the field effect tube Q4 can be turned off for pulse width modulation, so as to realize the speed control of the motor. Braking: braking is performed through dynamic braking, that is, when the motor rotates forward, a voltage for the motor reverse rotation is applied to perform rapid braking.

[0016] The core of the present invention is that when the shape of the occluder has been adjusted to be consistent with the shape of the fistula, the rotation of the motor is subject to a certain resistance, that is, the voltage at both ends of the motor will change suddenly. This is because when the motor speed suddenly decreases, the back electromotive force (EMF) will suddenly decrease, and at the same time, due to the existence of the bias resistor, the actual voltage at both ends of the motor will decrease. The differential detection circuit can detect the change in the actual voltage at both ends of the motor, and input the voltage signal change to the main control microcontroller. The main control microcontroller obtains the signal, adjusts the working mode of the motor, and brakes the motor to complete the process of shape control of the occluder.

[0017] Specifically, the power supply includes VCC and VCC3.3, the VCC is used to power the motor M, and the VCC3.3 is used to power the single chip microcomputer.

[0018] Preferably, the occluder morphology control circuit also includes an EEPROM storage circuit, and the EEPROM storage circuit uses a CAV25256VE-GT3 chip. EEPROM is a non-volatile memory, and for some complex control programs, it takes up a large storage space, and an external EEPROM storage circuit may be required during use.

[0019] Preferably, the occluder morphology control circuit also includes an NTC temperature detection circuit. The NTC (Negative Temperature Coefficient) temperature sensor is a thermistor whose resistance decreases as the temperature increases. This characteristic makes NTC a widely used temperature measurement element. The present invention adopts an NTC temperature sensor. The main purpose of setting an NTC temperature detection circuit in the drive circuit of the present invention is to monitor and protect the motor and its drive circuit from overheating damage. By monitoring the temperature in the motor or drive circuit, abnormal temperature rise can be discovered in time, and measures (such as reducing the load, reducing the speed, or completely shutting down the system) can be taken to avoid permanent damage caused by overheating.

[0020] Preferably, the occluder morphology control circuit also includes a voltage power supply detection circuit. The purpose is to protect the circuit from overvoltage and undervoltage. If the input voltage is too high, it may cause damage to components in the drive circuit and may even cause a fire. By monitoring the power supply voltage, timely measures can be taken when the voltage exceeds the safe range, such as cutting off the power supply or issuing a warning. When the supply voltage is lower than the minimum voltage required for normal operation, the motor may not operate normally, or it may operate unstably. This may result in performance degradation, control failure, or other unpredictable behavior. The power supply detection circuit can detect this situation and prevent the motor from operating under unsafe conditions.

[0021] Preferably, the main control microcontroller of the occluder morphology control circuit adopts stm32f103zet6. The microcontroller has more IO ports and ADC ports. For some occluders that need to control more control ropes, the stm32f103zet6 can be used to control 9 motors at one time. For some situations where more control is required, a combined control system composed of a single unit of stm32f103zet6 and a plurality of stm32f103zet6 can also be adopted. The combined control system is more related to the design of the microcontroller program, which will not be repeated.

[0022] The beneficial effects of the present invention are: The ability to control the shape of the occluder has been achieved, and the problems of difficulty in adjusting the position of the occluder, uncontrollable occlusion effect of the occluder, incomplete occlusion of the occluder, uneven pressure distribution of the occluder, etc., which are caused by the inability to control the shape of the occluder, can be better solved.

[0023] The technical solution of the present invention is simple. Compared with the currently conventionally used Hall effect sensor to detect the speed of the motor and control the motor speed, the solution of the present invention directly detects the differential change of the voltage across the motor, and after the voltage is detected by operational amplifier, the single-chip microcomputer directly outputs a control signal to control the motor M.

[0024] The occluder morphology control circuit of the technical solution of the present invention has a fast system response time. Since the variables involved in detection and execution are simple and do not require complex calculations, the software execution efficiency is very high during the process, and the system response time is within a few microseconds. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 4 is a schematic diagram of a driving circuit according to an embodiment of the present invention.

[0026] Figure 2 Schematic diagram of a differential detection circuit according to an embodiment of the present invention.

[0027] Figure 3 The schematic diagram of the circuit of the single chip microcomputer according to the embodiment of the present invention.

[0028] Figure 4 This is a schematic diagram of the EEPROM storage structure according to an embodiment of the present invention.

[0029] Figure 5 This is a schematic diagram of an NTC temperature detection circuit according to an embodiment of the present invention.

[0030] Figure 6 This is a schematic diagram of a voltage power supply detection circuit according to an embodiment of the present invention.

[0031] Figure 7 The figure is a schematic diagram of a power supply circuit and an indicator light according to an embodiment of the present invention. DETAILED DESCRIPTION

[0032] like Figure 1 The figure shows the principle diagram of the driving circuit of the present invention. The half side of the H bridge uses the chip EG2104 to drive the MOS tube. The EG2104 is a dedicated chip for gate driving of MOS tube and IGBT tube with SD function. It integrates the logic signal input processing circuit, dead zone control circuit, level shift circuit, pulse filtering circuit and output driving circuit. It is specially used for brushless motor controller, power supply Driving circuit in DC-DC. The logic input control signal of the IN pin controls the conduction and cutoff of the output MOS tube. "0" corresponds to LO high level and HO low level, and "1" corresponds to HO high level and LO low level. SD is the logic input control signal, which is valid at low level and forces LO and HO to output low level. "1" allows LO and HO to be controlled by IN input. "0" forces LO and HO to output low level. The HO of U21 (EG2104) is connected to the gate of MOS tube Q4, and the LO of U21 (EG2104) is connected to the gate of MOS tube Q7. Freewheeling diodes are set between the source and gate and between the source and drain of MOS tubes Q4, MOS tube Q7, MOS tube Q2, and MOS tube Q8. When MOSFET is used in a switching circuit, if the load is inductive (such as a motor, electromagnet, etc.), when the MOSFET is turned off, due to the characteristics of the inductance, a reverse electromotive force (also called back electromotive force or flywheel voltage) will be generated. This voltage may exceed the maximum Vds (drain-source voltage) rating of the MOSFET and cause damage to the MOSFET. The parallel diode can provide a low impedance path for this reverse current, thereby protecting the MOSFET from overvoltage damage. The freewheeling circuit composed of R130, D24, and R137 is used to protect the HO pin. The freewheeling circuit composed of R145, D37, and R153 is used to protect the LO pin. The other half of the H bridge is also driven by U22 (EG2104), and the freewheeling diodes D28, ZD4, D34, and ZD8, as well as the freewheeling circuit R131, D20, R138 and the freewheeling circuit R146, D38, and R154 are all mirrored and will not be repeated. The source of MOS tube Q7 is connected to the bias resistor R157, and the source of MOS tube Q8 is connected to the bias resistor R158. At the same time, the source of MOS tube Q7 is connected to the differential detection circuit I+_1, and the source of MOS tube Q8 is connected to the differential detection circuit I+_2. Since the differential detection circuit I+_1 and the differential detection circuit I+2 are the same, only the differential detection circuit I+1 is introduced.

[0033] like Figure 2As shown, the differential detection circuit schematic diagram of the embodiment, I+_1 is first connected to the capacitor C163 and the resistor R127 connected in series with the capacitor C163, the resistor R127 is connected in parallel with the differential amplifier circuit, the model of the differential amplifier circuit operational amplifier U1C is TL084IDR, one end of the resistor R127 is connected to the inverting input end of the operational amplifier U1C through the resistor R4 and the resistor R7, and one end of the resistor R127 is connected to the inverting input end of the operational amplifier U1C through the resistor R16 and the resistor R13. As shown in the figure, a high-frequency filter capacitor, namely a capacitor C5, a capacitor C20, a capacitor C4, a capacitor C10, and a capacitor C19 are also provided. A protection circuit is provided at the output end of the operational amplifier U1C, and the protection circuit includes a capacitor C13 and two diodes D1. One end of the capacitor C13 is connected to the output end of the operational amplifier U1C, and the other end of the capacitor C13 is connected to the input end of one of the diodes and the ground. The output end of the above diode is connected to the output end of the operational amplifier U1C and the input end of another diode, and the output end of the other diode is connected to VCC3.3. The specific working process of the differential detection circuit is as follows: When the motor M encounters resistance, the speed decreases, the back electromotive force E decreases, the voltage across the motor M decreases, the voltage across the capacitor C163 decreases, and the capacitor C163 discharges to form a voltage drop on the resistor R127. The operational amplifier U1C amplifies the voltage to the voltage range that the microcontroller can accept and inputs it into the microcontroller.

[0034] like Figure 3 The circuit diagram of the single-chip microcomputer is shown. The single-chip microcomputer of this embodiment adopts stm32f103zet6. The single-chip microcomputer controls 9 groups of motors and related signal ports. U37A is the control end of the single-chip microcomputer, and U37B is the functional end of the single-chip microcomputer. In U37A, M Control1 to M Control18 are connected to the SD pin of EG2104, M IN1 to M IN18 are connected to the IN pin of EG2104, and M+_1 to M+_9 are connected to the output end of the differential detection circuit in U37A, and M-_1 to M-_9 are connected to the output end of the differential detection circuit. U37B is the functional end of the single-chip microcomputer, involving power supply, grounding, serial communication, and external crystal oscillator related pins, such as OSC_IN and OSC_OUT, which involve the interface of the external crystal oscillator.

[0035] like Figure 4 The schematic diagram of the EEPROM storage structure is shown, which involves the chip U38 (CAV25256VE-GT3) as an external storage medium to store the program of the microcontroller. The RESET pin in U37B is connected to the WP pin of U38.

[0036] like Figure 5The schematic diagram of the NTC temperature detection circuit of the embodiment is shown, PC is an NTC resistor, one end of which is connected to resistor R286 and resistor R290, one end of resistor R290 is grounded, the other end of resistor R286 is connected to capacitor C247 and a clamping circuit, and the clamping circuit is composed of a diode group D113, the other end of capacitor C247 is grounded, and the other end of resistor R286 is also connected to the non-inverting input terminal of operational amplifier U41A, and the output terminal of operational amplifier U41A is connected to the NTC pin of microcontroller U37A through resistor R285.

[0037] like Figure 6 The voltage detection circuit of the present invention is shown, one end of the voltage to be measured VCC_DI is connected to resistor R292, one end of resistor R292 is connected to resistors R294 and R293, capacitor C251 is connected in parallel to resistor R294, and the other end of resistor R293 is connected to the clamping circuit, grounding capacitor C250, and V-12V pin of U37A, and the clamping circuit is composed of diode group D116.

[0038] like Figure 7 The figure shows the schematic diagram of the power supply circuit of the embodiment of the present invention. The power supply of this embodiment uses 12v, 5v, and 3.3v as the working voltage during operation. The voltage 3.3v is used to power the single-chip microcomputer and the EEPROM storage circuit, the voltage 5v is used to power the NTC temperature detection circuit, and the 12v is used to power the motor. In the figure, VCC_IN is a 12v voltage that is controlled by the chip U39 (model: LM2596S-5.0) and the KSI-IN pin in the single-chip microcomputer U37A, and is converted into a 5v voltage VCC_5. VCC_5 then converts the 5v voltage into a 3.3v voltage power supply through the chip U40 (model: LM1117RS-ADJ). When the 3.3v voltage is working normally, LED1 lights up, indicating that the voltages 12v, 5v, and 3.3v are all working normally.

[0039] Of course, the above are only typical examples of the present invention. In addition, the present invention may also have many other specific implementations. All technical solutions formed by equivalent replacement or equivalent transformation fall within the scope of protection required by the present invention.

Claims

1. Occluder morphology control circuit, characterized in that: Including main control microcontroller, drive circuit and power supply; The driving circuit adopts H-bridge driving, and the driving circuit includes H-bridge, freewheeling compensation circuit, driving chip, differential detection circuit, H-bridge includes field effect tube Q4, field effect tube Q7, field effect tube Q2, field effect tube Q8 and motor M, wherein the drain of field effect tube Q4 and field effect tube Q2 is connected to VCC, wherein one end of motor M is arranged on the source of field effect tube Q4 and the drain of field effect tube Q7, wherein one end of motor M is arranged on the source of field effect tube Q2 and the drain of field effect tube Q8, wherein the source of field effect tube Q7 and field effect tube Q8 is connected to bias resistor, and one end of bias resistor is grounded, the freewheeling compensation circuit is used to compensate for the inductive reactance of the field effect tube of H-bridge, the input end of differential detection circuit is arranged on the source of field effect tube Q7 and the source of field effect tube Q8, and the output end of differential detection circuit is connected to the ADC port of single-chip computer.

2. The occluder morphology control circuit according to claim 1, characterized in that: One end of the differential detection circuit is connected to a detection capacitor, one end of the detection capacitor is connected to a shunt resistor, one end of the shunt resistor is grounded, the shunt resistor is connected in parallel to the non-inverting input and inverting input of the differential amplifier, and the output of the differential amplifier is connected to the ADC port of the microcontroller.

3. The occluder morphology control circuit according to claim 2, characterized in that: A protection circuit is provided at the output end of the differential amplifier, and the protection circuit includes a capacitor C13 and two diodes. One end of the capacitor C13 is connected to the output end of the differential amplifier, and the other end of the capacitor C13 is connected to the input end of one of the diodes and the ground. The output end of the above diode is connected to the output end of the differential amplifier and the input end of another diode, and the output end of the other diode is connected to VCC3.

3.

4. The occluder morphology control circuit according to claim 3, characterized in that: The power supply includes VCC and VCC3.

3. The VCC is used to power the motor M, and the VCC3.3 is used to power the single-chip microcomputer.

5. The occluder morphology control circuit according to claim 1, characterized in that: It also includes an EEPROM storage circuit, which uses a CAV25256VE-GT3 chip.

6. The occluder morphology control circuit according to claim 1, characterized in that: Also includes NTC temperature detection circuit.

7. The occluder morphology control circuit according to claim 1, characterized in that: A voltage supply detection circuit is also included.

8. The occluder morphology control circuit according to claim 1, characterized in that: The main control microcontroller adopts stm32f103zet6.

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