Breathing circuit short circuit protection circuit and breathing apparatus
By designing a short-circuit protection circuit in a respiratory device, and using a microcontroller and a short-circuit protection module to cut off the short-circuit current, the problems of equipment damage and fire risk in the short-circuit situation of existing respiratory devices are solved, and the self-protection and maintenance of the equipment are simplified.
Patent Information
- Application Number
- JP2025000634U
- Authority / Receiving Office
- JP · JP
- Patent Type
- Utility models
- Current Assignee / Owner
- Priority Date
- 2024-12-18
- Filing Date
- 2025-02-27
- Publication Date
- 2025-05-01
- Estimated Expiration
- 2035-02-27
AI Technical Summary
In the case of short circuit of existing respiratory equipment, internal equipment is prone to damage, resulting in increased maintenance costs and a fire risk.
A short-circuit protection circuit for breathing circuit is designed, including a short-circuit protection module, a breathing heating module, a heating control/short-circuit protection module and a microcontroller. The protection circuit receives temperature signals through the microcontroller, adjusts the heating current, and cuts off the short-circuit current when a short-circuit occurs to prevent damage to the device.
It realizes protection of respiratory equipment in short circuit situations, avoids equipment damage and fire risks, simplifies maintenance processes, reduces maintenance costs, and improves usage safety.
Smart Images
Figure 0003251124000001_ABST
Abstract
Description
[Technical field]
[0001] The present invention relates to the technical field of medical equipment, and in particular to a breathing circuit short circuit protection circuit and a breathing apparatus. [Background technology]
[0002] In the field of medical devices, existing respiratory devices send heated gas to a patient through a circuit and receive gas from the patient, which helps to reduce the probability of infection and tissue damage to the patient. Here, a circuit with a heating wire is generally integrated with a temperature sensor (Negative Temperature Coefficient, NTC), and specifically, one end of the circuit with the heating wire is connected to the patient's respiratory port and the other end is connected to a respiratory host, which outputs an appropriate heating temperature to heat the respiratory duct and provide an appropriate temperature to the user, and the heating wire in the circuit plays a role of maintaining the temperature and humidity of the gas and reducing condensation water. In the respiratory device with the heating wire, the inside of the circuit is often in a high temperature and humidity environment, and water may seep out from the accumulated condensation water, causing a short circuit between each wiring of the internal connection part. If a short circuit occurs between the heating wire wiring and the temperature sensor wiring, it is easy to damage the internal devices of the machine, and damage precision devices such as fuses on the printed circuit board circuit (Printed Circuit Board Assembly, PCBA) and IO interface of MCU, resulting in additional maintenance costs. A burnt circuit in the respiratory device may generate sparks and cause a fire.
[0003] Therefore, the prior art is open to further improvement and development. Summary of the Invention [Problem to be solved by the invention]
[0004] In view of the shortcomings of the above prior art, the objective of the present invention is to provide a breathing circuit short circuit protection circuit and a breathing apparatus to solve the problem in the prior art that when the breathing apparatus is short-circuited, the internal device of the machine is easily damaged, and the original device in the circuit needs to be frequently replaced, resulting in additional maintenance costs. [Means for solving the problem]
[0005] The technical solutions of the present invention are as follows: The breathing circuit short circuit protection circuit is equipped with a short circuit protection module, a breathing heating module, a heating control and short circuit protection module, and a microcomputer. The heating control and short circuit protection module is connected to the respiratory heating module, and the heating control and short circuit protection module is used to receive a heating control signal output from the microcomputer in the case of normal operation of the respiratory heating module, adjust the heating current of the respiratory heating module, feed back the heating current to the microcomputer, and cut off the short circuit current when the heating control and short circuit protection module is short-circuited; The respiratory heating module is electrically connected to the heating control and short circuit protection module and the short circuit protection module respectively, and the respiratory heating module is used for heating the gas in the heating unit according to the heating current, detecting the temperature of the gas in the respiratory heating module, and inputting the temperature signal into the input end of the short circuit protection module; The short circuit protection module is used to collect the temperature signal in the respiratory heating module when the respiratory heating module is in normal operation, and output the temperature signal to the temperature signal collecting end of the microcomputer, and cut off the short circuit current when the short circuit protection module is short circuited; The current detection end and signal control end of the microcontroller are connected to the heating control and short circuit protection module, and the temperature detection end of the microcontroller is connected to the output end of the short circuit protection module, and the microcontroller is used to receive the heating current and output a heating control signal to the heating control and short circuit protection module, and further receive the temperature signal and output the temperature signal to a host computer.
[0006] As a further improvement of the present invention, the short circuit protection module comprises: a first operational amplifier, a first resistor, a second resistor, a first transistor, a first capacitor, and a first recoverable fuse; The output end of the first operational amplifier is connected to the first end of the first resistor, the positive end of the power supply of the first operational amplifier is connected to a first power supply voltage, the negative end of the power supply of the first operational amplifier is grounded, the inverting input end of the first operational amplifier is connected to the output end of the first operational amplifier, the positive phase input end of the first operational amplifier is connected to one end of the first recoverable fuse, the first end of the second resistor is connected to the cathode of the first transistor and a common terminal of one end of the first capacitor, the second end of the second resistor is connected to the first power supply voltage, the second end of the first resistor is connected to the temperature detection end of the microcontroller, the other end of the first recoverable fuse is connected to the respiratory heating module, the anode of the first transistor is connected to the respiratory heating module, and the other end of the first capacitor and the common terminal of the anode of the first transistor are grounded.
[0007] As a further improvement of the present invention, the present invention further comprises a filter module, one end of the filter module is connected to the first power supply voltage and the other end is connected to the short circuit protection module, which is used to reduce ripple and interference noise in the first power supply voltage and provide a stable DC output.
[0008] As a further improvement of the present invention, the heating control and short circuit protection module includes a short circuit protection unit and a heating control unit; One end of the short circuit protection unit is connected to a second power supply voltage, and the other end of the short circuit protection unit is connected to the respiratory heating module, and the short circuit protection unit is used to cut off the connection between the second power supply voltage and the respiratory heating module when a short circuit occurs; One end of the heating control unit is connected to the respiratory heating module and the other end is grounded, and the heating control unit is connected to the current detection end and signal control end of the microcontroller, and is used to receive the heating control signal from the microcontroller and control the heating current flowing through the respiratory heating module.
[0009] As a further improvement of the present invention, the respiratory heating module includes a temperature sensor and a heating device, one end of the temperature sensor is connected to a first input terminal of the short circuit protection module, and the other end of the temperature sensor and the second input terminal of the short circuit protection module are grounded and used to detect the connection between the heating device and the heating control and short circuit protection module.
[0010] As a further improvement of the present invention, the filter module includes a second capacitor and a third capacitor, one end of the second capacitor and one end of the third capacitor are connected to the first power supply voltage and the short circuit protection module, and the other end of the second capacitor and the other end of the third capacitor are grounded.
[0011] As a further improvement of the present invention, the short circuit protection unit includes a second recoverable fuse, one end of the second recoverable fuse is connected to a second power supply voltage, and the other end of the second recoverable fuse is connected to the respiratory heating module.
[0012] As a further improvement of the present invention, the heating control unit includes a first field effect tube, a third resistor and a fourth resistor; The gate of the first field effect tube is connected to one end of the third resistor, the drain of the first field effect tube is connected to one end of the fourth resistor, the source of the first field effect tube is connected to the respiratory heating module, the other end of the third resistor and the source of the first field effect tube are respectively connected to the microcontroller, and the other end of the fourth resistor is grounded.
[0013] In a further refinement of the invention, the first transistor is an avalanche breakdown diode.
[0014] Moreover, the present invention further provides a breathing apparatus comprising a breathing device, a circuit and a breathing circuit short circuit protection circuit as described above.
[0015] The present invention discloses a respiratory circuit short circuit protection circuit and a respiratory device, comprising a short circuit protection module, a respiratory heating module, a heating control and short circuit protection module and a microcomputer, the heating control and short circuit protection module is connected to the respiratory heating module, the heating control and short circuit protection module is used to receive a heating control signal output from the microcomputer in the case of normal operation of the respiratory heating module, adjust the heating current of the respiratory heating module, and feed back the heating current to the microcomputer, and cut off the short circuit current when the heating control and short circuit protection module is short-circuited, the respiratory heating module is electrically connected to the heating control and short circuit protection module and the short circuit protection module respectively, the respiratory heating module adjusts the air in the heating unit based on the heating current. The short circuit protection module is used to heat the body, detect the temperature of the gas in the respiratory heating module, and input the temperature signal to the input end of the short circuit protection module, and the short circuit protection module is used to collect the temperature signal in the respiratory heating module in the normal operation of the respiratory heating circuit, output the temperature signal to the temperature signal collection end of the microcomputer, and cut off the short circuit current when the short circuit protection module is shorted, and the current detection end and signal control end of the microcomputer are connected to the heating control and short circuit protection module, and the temperature detection end of the microcomputer is connected to the output end of the short circuit protection module, and the microcomputer is used to receive the heating current, output the heating control signal to the heating control and short circuit protection module, and further receive the temperature signal and output the temperature signal to the upper computer. The invention uses a recoverable fuse in the heating device circuit as a short circuit protection device and designs a short circuit protection module in the temperature signal detection circuit, thereby realizing the self-protection of the respiratory device when a short circuit occurs at any two pins of the circuit, and allows the host and the circuit to recover to a normal state, and can be operated by simply replacing the circuit, which is easy to maintain and improves the safety of use. [Brief description of the drawings]
[0016] In order to more clearly describe the embodiments of the present invention or the technical solutions in the prior art, the following briefly describes the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings described below are only some embodiments of the present invention, and those skilled in the art can obtain other drawings based on the structures shown in these accompanying drawings without creative labor. [Figure 1] 1 is a block diagram showing the principle of a breathing circuit short-circuit protection circuit provided by the present invention; FIG. [Diagram 2] 1 is a circuit diagram of a breathing circuit short circuit protection circuit provided by the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] The present invention provides a breathing circuit short circuit protection circuit and a breathing apparatus, in order to make the objectives, technical solutions and effects of the present invention clearer and more precise, the present invention will be described in more detail below with reference to the accompanying drawings and examples, It should be understood that the specific embodiments described herein are only used for the interpretation of the present invention, and are not intended to limit the present invention.
[0018] In the embodiments and claims, unless otherwise specified, the articles "a", "one", "the", and "the" include the plural. When "first", "second", etc. are used in the examples of the invention, the terms "first", "second", etc. are used for descriptive purposes only and do not indicate or imply the relative importance or number of such technical features. Thus, a feature defined as "first" or "second" explicitly or implicitly includes at least one such feature.
[0019] Furthermore, it is to be understood that the term "comprising" as used in the present specification means the presence of said features, integers, steps, operations, devices and / or assemblies, but does not exclude the presence or addition of one or more other features, integers, steps, operations, devices, assemblies and / or combinations thereof. It is to be noted that when an element is said to be "connected" or "coupled" to another element, it may be directly connected or coupled to the other element, or intermediate devices may be present. Furthermore, as used herein, "connected" or "coupled" includes wireless connection or coupling. As used herein, the term "and / or" includes all or any units and all combinations of one or more associated listed items.
[0020] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention belongs, as would be understood by those of ordinary skill in the art. In addition, terms as defined in a general dictionary should be understood to have a meaning consistent with the meaning in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless otherwise defined in this specification.
[0021] In addition, the technical solutions among the various embodiments may be combined with each other, but only on the premise that they are achievable by a person skilled in the art; if a combination of technical solutions appears to be contradictory or unachievable, it should be assumed that such a combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.
[0022] 1, some preferred embodiments of the present invention provide a respiratory circuit short circuit protection circuit, comprising a short circuit protection module 100, a respiratory heating module 200, a heating control and short circuit protection module 300 and a microcomputer 400, the heating control and short circuit protection module 300 is connected to the respiratory heating module 200, the heating control and short circuit protection module 300 is used to receive a heating control signal output from the microcomputer 400 in the case of normal operation of the respiratory heating module 200, adjust the heating current of the respiratory heating module 200, and feed back the heating current to the microcomputer 400, and cut off the short circuit current when the heating control and short circuit protection module 300 is short-circuited, the respiratory heating module 200 is electrically connected to the heating control and short circuit protection module 300 and the short circuit protection module 100 respectively, the respiratory heating module 200 heats the gas in the heating unit according to the heating current, and ... It is used to detect the temperature of the gas in the heating module 200 and input the temperature signal to the input end of the short circuit protection module 100, the short circuit protection module 100 is used to collect the temperature signal in the respiratory heating module 200 in the case of normal operation of the respiratory heating circuit, output the temperature signal to the temperature signal collecting end of the microcomputer 400, and cut off the short circuit current when the short circuit protection module is short-circuited, the current detection end and the signal control end of the microcomputer 400 are connected to the heating control and short circuit protection module 300, the temperature detection end of the microcomputer 400 is connected to the output end of the short circuit protection module 100, the microcomputer 400 is used to receive the heating current and output a heating control signal to the heating control and short circuit protection module 300, the heating control signal is a PWM signal, and the heating control and short circuit protection module 300 is further used to receive the temperature signal and output the temperature signal to a higher-level computer.
[0023] Specifically, during normal operation, the heating control and short circuit protection module 300 is connected to the respiratory heating module 200, controls the heating current input to the respiratory heating module 200, and controls the heating degree of the respiratory heating module 200, and the respiratory heating module 200 contacts with gas to heat the gas, and at the same time detects the real-time temperature of the gas in the environment at the current time and generates a temperature detection signal. At the same time, if the temperature during normal operation of the respiratory circuit short circuit protection circuit is regarded as room temperature, the short circuit protection module 100 is regarded as a lead wire, and the temperature detection end of the microcomputer 400 is connected to the respiratory heating module 200 and collects the temperature signal output from the respiratory heating module 200.
[0024] When short-circuited, the respiratory heating module 200 does not participate in voltage division because no current flows through it, and the operating voltage of the heating control and short circuit protection module 300 is greater than the maximum voltage that the short circuit protection module 100 and the microcomputer 400 can transmit, so that the short circuit current in the circuit is much greater than the normal operating current, which may lead to damage to electronic devices, especially precision equipment such as microcomputers. In some cases, the short circuit protection module 100 and the microcomputer 400 may be short-circuited and connected to the heating control and short circuit protection module 300. Here, take as an example the case where the second end and the third end of the respiratory heating module are short-circuited, that is, the short circuit protection module 100 and the microcomputer 400 circuit are connected to the voltage input end of the heating control and short circuit protection module 300. At this time, the respiratory heating module is short-circuited, and the input terminal of the short-circuit protection module 100 is the operating voltage of the heating control and short-circuit protection module 300, and the short-circuit protection module 100 cuts off the connection between the respiratory heating module 200 and the heating control and short-circuit protection module 300 with current limiting, protecting the microcomputer 400 from short-circuiting, and preventing the operating voltage of the heating control and short-circuit protection module 300 from surging to the input terminal of the microcomputer 400 and damaging the microcomputer 400. In the case of a short circuit, the host and other circuits can be restored to a normal state, and only the circuit needs to be replaced, without the need for maintenance and replacement, making the maintenance of the respiratory circuit easier and more reliable, reducing maintenance costs, and improving safety during use.
[0025] Further, referring to FIG. 2 together, the short circuit protection module 100 includes a first operational amplifier U1B, a first resistor R1, a second resistor R2, a first transistor D1, a first capacitor C1 and a first recoverable fuse F1, the output end of the first operational amplifier is connected to a first end of the first resistor, the positive end of the power supply of the first operational amplifier is connected to a first power supply voltage, the negative end of the power supply of the first operational amplifier is grounded, the inverting input end of the first operational amplifier is connected to the output end of the first operational amplifier, and the positive phase input of the first operational amplifier is connected to the output end of the first operational amplifier. The first end of the first recoverable fuse is connected to one end of the first recoverable fuse, the first end of the second resistor is connected to the cathode of the first transistor and a common terminal of one end of the first capacitor, the second end of the second resistor is connected to a first power supply voltage, the second end of the first resistor is connected to a temperature detection terminal of the microcontroller, the other end of the first recoverable fuse is connected to the respiratory heating module, the anode of the first transistor is connected to the respiratory heating module, and the other end of the first capacitor and the common terminal of the anode of the first transistor are grounded.
[0026] Specifically, the first power supply voltage is 3.3V. When the abnormal overcurrent flows through the recoverable fuse, it generates heat and its internal resistance increases, reducing the abnormal overcurrent; when the abnormal overcurrent fault is released, the conductive path in the recoverable fuse is restored and returns to its original low resistance state. The input terminal of the short circuit protection module 100 is connected to the respiratory heating module 200, and when the gas temperature in the circuit changes, the resistance value of the temperature sensor itself also changes, and at this time, the voltage at the output terminal of the temperature sensor is a temperature signal. During the normal operation of the respiratory heating module, the first fuse operates normally, and the first fuse is regarded as a lead wire, which is equivalent to the positive input terminal of the first operational amplifier U1B being directly connected to the respiratory heating module 200, and the inverting input terminal of the first operational amplifier U1B is connected to the output terminal of the first operational amplifier U1B. At this time, the first operational amplifier U1B is a voltage follower, and the output terminal voltage of the first operational amplifier U1B follows the voltage change of the positive input terminal of the first operational amplifier U1B, and during normal operation, the voltage of the temperature signal collecting terminal of the microcomputer 400 is the temperature signal output from the temperature sensor. The microcomputer 400 receives the temperature signal, stores it in the microcomputer register, transmits it to the upper computer, and displays it to the user, thereby realizing the temperature monitoring of the respiratory gas. Optionally, the microcomputer 400 may appropriately process and package the data before outputting the temperature signal, and the transmission method may be wired transmission or wireless transmission, and the specific embodiment of the temperature signal transmission is not limited in the present invention.
[0027] When the short circuit protection module 100 is shorted to another wiring, the first transistor D1 clamps the voltage value of the positive input terminal of the first operational amplifier U1B by its tube voltage drop. If the first transistor D1 is an avalanche breakdown diode, the voltage of the positive input terminal of the first operational amplifier U1B is limited to 7V within a certain time, protecting the circuit from the impact of a transient high voltage surge, and the first transistor D1 forms a voltage regulator circuit, preventing the input voltage of the short circuit protection module 100 from being directly applied to the positive input terminal of the first operational amplifier U1B and damaging the first operational amplifier U1B. When a short circuit occurs in the circuit, the first recoverable fuse F1 rapidly increases its impedance, suppresses abnormal current, and opens before the first transistor D1 is damaged, preventing the first transistor D1 from being destroyed due to an excessively high voltage across itself under a short circuit, and protecting the first operational amplifier U1B and the microcomputer 400. When the short circuit is removed, the first recoverable fuse F1 is restored to a conductive state, and no damage is caused by the short circuit. The first operational amplifier U1B is the positive input terminal of the voltage follower, and is equal to the voltage at the output terminal, and exhibits a high resistance state, which corresponds to an open state. When a short circuit occurs in the circuit, the first operational amplifier U1B, the first transistor D1 and the first recoverable fuse F1 in the short circuit protection module 100 are short-circuited to protect the microcomputer 400, and at the same time, the devices in the short circuit protection module 100 are not damaged by the short circuit, and the subsequent use of the machine is not affected. The short-circuited respiratory heating module can be replaced.
[0028] In some other preferred embodiments, the power supply positive end of the first operational amplifier U1B is further connected to a filter module 500, one end of the filter module 500 is connected to the first power supply voltage and the other end is connected to the short circuit protection module 100. The filter module 500 includes a second capacitor C2 and a third capacitor C3, one end of the second capacitor C2 and one end of the third capacitor C3 are connected to the first power supply voltage and the short circuit protection module, and the other end of the second capacitor C2 and the other end of the third capacitor C3 are grounded, which are used to reduce the ripple and interference noise in the first power supply voltage, provide a stable DC output, reduce the interference caused by interference noise on the short circuit protection circuit signal detection, and make the power supply signal input to the first operational amplifier U1B more stable.
[0029] Further, the heating control and short circuit protection module 300 includes a short circuit protection unit 310 and a heating control unit 320, one end of the short circuit protection unit 310 is connected to a second power supply voltage, the other end of the short circuit protection unit 310 is connected to the respiratory heating module 200, the short circuit protection unit 310 is used to cut off the connection between the second power supply voltage and the respiratory heating module 200 in case of a short circuit, one end of the heating control unit 320 is connected to the respiratory heating module 200, and the other end is grounded, the heating control unit 320 is connected to the current detection end and signal control end of the microcontroller, and is used to receive a heating control signal from the microcontroller and control the heating current flowing through the respiratory heating module 200.
[0030] The short circuit protection unit 310 includes a second recoverable fuse F2, one end of the second recoverable fuse F2 is connected to a second power supply voltage, and the other end of the second recoverable fuse F2 is connected to the respiratory heating module 200. The heating control unit 320 includes a first field effect tube Q1, a third resistor R3 and a fourth resistor R4, wherein the gate of the first field effect tube Q1 is connected to one end of the third resistor R3, the drain of the first field effect tube is connected to one end of the fourth resistor, the source of the first field effect tube is connected to the respiratory heating module, the other end of the third resistor and the source of the first field effect tube are respectively connected to the microcomputer, and the other end of the fourth resistor is grounded, the first field effect tube Q1 is an N-channel field effect tube, the first field effect tube Q1 controls the heating current flowing through the respiratory heating module through the duty ratio of the heating control signal at the gate, the heating control signal is a PWM signal, the output signal of the microcomputer 400 is greater than the gate voltage of the first field effect tube Q1, the first field effect tube Q1 is conductive, the output signal of the microcomputer 400 is less than the gate voltage of the first field effect tube Q1, the first field effect tube Q1 is cut off.
[0031] Specifically, the first power supply voltage is 3.3V, and the second power supply voltage is 24V. The first recoverable fuse and the second recoverable fuse are polymeric positive temperature coefficient (PPTC) thermistors. When an abnormal overcurrent passes through the self-recovery fuse, heat is generated and the polymer matrix expands, and the conductive particles wound around the polymer matrix are separated, cutting off the conductive path of the self-recovery fuse, and the self-recovery fuse resistance increases, so that the abnormal overcurrent is reduced, the wiring is cut off, and the wiring protection function is performed. When the abnormal overcurrent fault is removed, the self-recovery fuse polymer matrix contracts to its original shape and reconnects the conductive particles, automatically recovering the conductive path, and the resistance of the recoverable fuse returns to its original low resistance state. Compared with the conventional melting type fuse, it does not need to be replaced after a short circuit, significantly reducing the usage cost and achieving multiple short circuit protection functions.
[0032] During the normal operation of the respiratory heating module, the second recoverable fuse F2 inside the short circuit protection unit 310 is conductive, the first end of the heating device in the respiratory heating module is connected to the short circuit protection unit 310 through the respiratory heating module 200, and the second end of the heating device is connected to the heating control unit 320 through the respiratory heating module 200. At this time, the current of the heating device circuit flows through the short circuit protection unit 310, the respiratory heating module 200, the heating device, and then through the respiratory heating module 200 and the heating control unit 320 before being grounded to GND. The current of the microcomputer 400 controls the on / off of the first field effect tube Q1 by controlling the duty ratio of the heating control signal output, and further controls the temperature of the heating device.
[0033] In a further embodiment of some preferred embodiments, as shown in FIG. 2, the respiratory heating module 200 is electrically connected to the short circuit protection module 100 and the heating control and short circuit protection module 300 by a 6-pin circular jumper block, and the other end of the 6-pin circular jumper block is electrically connected to the respiratory heating module 200. The respiratory heating module 200 includes a temperature sensor (not shown) and a heating device (not shown). One end of the temperature sensor is connected to a first input end of the short circuit protection module, and the other end of the temperature sensor and the second input end of the short circuit protection module are grounded, and are used to detect the temperature of the gas in the respiratory heating module and input a temperature signal to the input end of the short circuit protection module. Both ends of the heating device are respectively connected to the heating control and short circuit protection module, and heat the gas in the heating unit according to the heating current.
[0034] Each pin in the jumper block is electrically connected to the respiratory heating module through a data line. The first end of the respiratory heating module 200 is connected to the heating control unit 320, the second end of the respiratory heating module 200 is connected to the heating short circuit protection module 100, the third end of the respiratory heating module 200 is connected to the short circuit protection module 100, and the fourth end of the respiratory heating module 200 is grounded. The second and third ends of the respiratory heating module 200 are connected to the relevant electronic devices of other medical equipment, and in some preferred embodiments of the present invention, the idle port of the respiratory heating module is also connected to the temperature sensor circuit, and the connection relationship of the circuit is the same as the above short circuit protection module 100-microcomputer 400 circuit, and is not repeated here.
[0035] Furthermore, the temperature detection terminal TEMP_AD of the microcomputer 400 is connected to the short circuit protection module 100, and the current detection terminal CURR and the signal control terminal PWM of the microcomputer 400 are respectively connected to the heating control and short circuit protection module 300. Specifically, the temperature detection terminal TEMP_AD of the microcomputer 400 is connected to the output terminal of the first operational amplifier U1B, the current detection terminal of the microcomputer 400 is connected to the source of the first field effect tube Q1, and the signal control terminal PWM of the microcomputer 400 is connected to the gate of the first field effect tube Q1. The microcomputer 400 is used to receive the heating device current signal at the current detection terminal CURR and the temperature signal at the temperature detection terminal TEMP_AD, and output the heating control signal for controlling the heating control and short circuit protection module 300.
[0036] Specifically, the I / O port of the microcomputer 400 must have an ADC function and can convert an analog signal into a digital signal. The microcomputer 400 is used to receive a heating wire current signal at a current detection terminal CURR and output a corresponding short circuit situation, and at the same time, the microcomputer 400 is used to receive a temperature signal at a temperature detection terminal TEMP_AD and output a heating control signal for controlling the heating control and short circuit protection module 300. In some preferred embodiments, the microcomputer 400 is preferably an STM32F407ZGTx chip.
[0037] Specifically, one end of the short circuit protection unit 310 is connected to the second power supply voltage, the other end of the short circuit protection unit 310 is connected to one end of the heating device through the second pin of the circular jumper block in the respiratory heating module 200, one end of the heating control unit 320 is connected to the other end of the heating device through the second pin of the circular jumper block in the respiratory heating module 200, and the short circuit protection unit 310, the heating device and the heating control unit 320 form a heating branch circuit. The first input end of the short circuit protection module 100 is connected to one end of the temperature sensor through the third pin of the circular jumper block in the respiratory heating module 200, and the second input end of the short circuit protection module 100 is connected to the other end of the temperature sensor through the third pin of the circular jumper block in the respiratory heating module 200, and the short circuit protection module 100 and the temperature sensor form a temperature monitoring branch circuit.
[0038] During normal operation of the respiratory heating module, the first power supply voltage supplies power to the short circuit protection module 100 and the temperature sensor, and when the temperature in the respiratory heating module 200 changes, the resistance of the temperature sensor itself changes accordingly, and the voltage division value of the second resistor R2 and the temperature sensor changes, and the output terminal voltage of the first operational amplifier as a voltage follower changes accordingly. At this time, the microcomputer stores the sampled voltage value of the temperature detection terminal in a register, and sends a temperature signal to an upper computer to display the current temperature value of the gas in the respiratory heating module 200 to the user. At the same time, the second power supply voltage of 24V supplies power to the heating device in the respiratory heating module 200, and at this time, the short circuit protection unit 310, the heating device and the heating control unit 320 are connected in series, and the current detection terminal of the microcomputer is connected to the source of the first field effect tube Q1, and the current value at the source of the first field effect tube Q1 is the heating current flowing through the heating device. The gate of the first field effect tube Q1 is connected to the signal control terminal PWM of the microcontroller 400, and the duty ratio of the heating control signal is adjusted to control the on / off of the first field effect tube Q1, and further controls the magnitude of the heating current of the heating device in the respiratory heating module 200, and controls the heating state of the respiratory heating module.
[0039] When there is a short circuit inside the respiratory heating module 200, any two of the pins are short-circuited, and the microcomputer 400 judges the short circuit status between the pins inside the respiratory heating module 200 through the current detection terminal CURR. The short circuit protection and judgment methods are as follows: When the first end and the second end, or the fourth end and the second end of the respiratory heating module 200 are short-circuited, a short circuit occurs in the circuit, and the second recoverable fuse F2 is regarded as open, and the second power supply voltage is disconnected from the circuit. When the short-circuit state is removed, the second recoverable fuse F2 is restored to a normal operating state.
[0040] When the first and fourth terminals of the respiratory heating module 200 are short-circuited, the circuit is not powered on and the circuit is not damaged by short-circuit current, and at this time, there is no current at the current detection terminal CURR of the microcomputer 400 and it is not controlled by the signal control terminal PWM of the microcomputer 400. The microcomputer 400 can inform the short circuit between the fourth terminal and the first terminal of the respiratory heating module 200 through the signal control of the current detection terminal CURR and the signal control terminal PWM.
[0041] When the fourth and third terminals of the respiratory heating module 200 are short-circuited, the positive input terminal of the first operational amplifier U1B is grounded, the voltage of the first operational amplifier U1B follows the positive input terminal, and the voltage value of the first resistor R1 is also 0V. At this time, the voltage detected by the temperature detection terminal TEMP_AD of the microcomputer 400 is 0V. The microcomputer 400 can inform that a short circuit has occurred between the fourth and third terminals of the respiratory heating module 200 according to the voltage value of the temperature detection terminal TEMP_AD.
[0042] When the second and third ends or the first and third ends of the respiratory heating module 200 are short-circuited, the first transistor D1 and the first operational amplifier U1B are used to pull down the voltage in the circuit before the first recoverable fuse F1 is cut off, to prevent the surge voltage from damaging the circuit. Specifically, the first transistor D1 in the circuit limits the voltage to its tube voltage drop of about 7V, and without this device, the second power supply voltage of 24V is directly applied to the positive input terminal of the first operational amplifier U1B, which will damage the first operational amplifier U1B. At the same time, the first operational amplifier U1B follows the sampled temperature signal, and the positive input terminal as a voltage follower is equal to the voltage of the output terminal, and exhibits a high blocking state, which corresponds to an open state, and at the same time limits the voltage to 3.3V, preventing the clamp voltage of 7V of the first transistor D1 from being directly applied to the I / O port of the temperature detection terminal TEMP_AD of the microcomputer 400 and damaging the I / O port of the microcomputer 400. At this time, the voltage across the first transistor D1 is too high, and the first transistor D1 is also short-circuited as an avalanche breakdown diode, and the internal current increases rapidly, damaging the first transistor D1. Before the first transistor D1 is damaged by the short circuit, the first recoverable fuse F1 current-limits the circuit, and the resistance value increases rapidly, and finally the first recoverable fuse F1 corresponds to an open state, protecting the electronic device in the short circuit protection module 100 and the microcomputer 400.
[0043] In summary, when different types of short circuits occur in the respiratory heating module, each electronic device in the circuit is protected from short circuits, and the circuit interruption fault can be cleared by simply replacing the shorted respiratory heating module during maintenance, and the first recoverable fuse F1 is automatically restored to a conductive state after the short circuit fault is cleared. When a short circuit occurs in the circuit at any two pins of the circuit, the host and the circuit can be restored to a normal state by simply replacing the circuit, which makes maintenance easier and improves safety during use.
[0044] Based on the same idea, the present invention further provides a respiratory device with short circuit protection function, comprising a respiratory device, a circuit and the above-mentioned respiratory circuit short circuit protection circuit, the respiratory device can be an anesthesia device or a respiratory device, at least one wire in the circuit is respectively connected to a temperature sensor and a heating wire, suitable for connecting a patient with an anesthesia device and a respiratory device, and providing a passage for the patient's inhalation and exhalation. Specifically, a respiratory heating module of the respiratory circuit short circuit protection circuit is provided in the circuit and electrically connected to other modules of the respiratory circuit short circuit protection circuit through a circular jumper block. The temperature sensor is connected to the short circuit protection module 100 through the respiratory heating module 200 and is used to receive a heating control signal output from the heating control and short circuit protection module 300, and the heating device is connected to the heating control and short circuit protection module 300 through the respiratory heating module 200, and can adjust the air temperature in the circuit according to the heating control signal to reduce moisture condensation.
[0045] Specifically, taking the heating device as an example, the heating wire is uniformly distributed in a spiral shape in the entire circuit, which increases the heat conduction area and improves the air heating efficiency. Similarly, the temperature sensor is electrically connected to the wiring in the circuit, and the temperature sensor is used to detect the temperature of the air in the circuit and output a temperature signal to the respiratory heating module 200, which is used to output the temperature signal to the microcomputer 400. When the microcomputer 400 receives the temperature signal, it obtains the air temperature in the circuit at this time from the temperature signal, and outputs a corresponding temperature control signal to the heating control and short circuit protection module 300. The heating control and short circuit protection module 300 is connected to the heating device through the respiratory heating module 200, and when the heating control and short circuit protection module 300 receives the corresponding heating control signal, the output end of the heating control and short circuit protection module 300 outputs a corresponding heating signal, and controls the heating power of the heating device through the heating signal, thereby realizing the feedback and adjustment of the air temperature in the circuit. In concrete implementation, the connection method and number of the wires in the respiratory heating module 200 and the circuit can be changed according to the actual production and use process needs, and are not limited here.
[0046] The present invention provides a breathing circuit short-circuit protection circuit and a breathing apparatus, which has the following beneficial effects: by using a recoverable fuse in the heating device circuit as the short-circuit protection device and designing a short-circuit protection module in the temperature signal detection circuit, the technical problem of repeatedly replacing the short-circuit protection device in the prior art is solved, and the self-protection of the breathing apparatus is realized when a short circuit occurs on any two pins of the circuit, the host and the circuit are also restored to a normal state, and the breathing apparatus can be operated by replacing the circuit, which makes maintenance easier and improves safety during use.
[0047] Furthermore, unless mutually inconsistent, the embodiments and features of the embodiments in the present invention can be combined with each other.
[0048] In addition, in this invention, the specific structure and operating principle of the invention will be described using a breathing circuit short-circuit protection circuit and a breathing apparatus having a heating function and a short-circuit protection function as examples. However, it should be noted that the application of the invention is not limited to a breathing circuit short-circuit protection circuit and a breathing apparatus having a heating function and a short-circuit protection function, and can also be applied to the use of other similar devices.
[0049] It should be understood that the present invention is not limited to the exact construction already described above and illustrated in the accompanying drawings, but various modifications and changes can be made without departing from the scope of the present invention, which is limited only by the scope of the appended claims.
[0050] It should be noted that the application of the present invention is not limited to the above examples, and a person skilled in the art may improve or modify the present invention according to the above description, and all such improvements and modifications are intended to be included in the scope of the appended claims of the present invention. [Explanation of symbols]
[0051] 100 Short Circuit Protection Module 200 Respiration Heating Module 300 Heating Control and Short Circuit Protection Module 400 Microcomputer 500 Filter Module
Claims
1. Equipped with a short circuit protection module, a breathing heating module, a heating control / short circuit protection module, and a microcomputer, The heating control and short circuit protection module is connected to the respiratory heating module, and the heating control and short circuit protection module is used to receive the heating control signal output from the microcomputer when the respiratory heating module is in normal operation, adjust the heating current of the respiratory heating module, feed back the heating current to the microcomputer, and cut off the short circuit current when the heating control and short circuit protection module is short-circuited; The respiratory heating module is electrically connected to the heating control and short circuit protection module and the short circuit protection module respectively, and the respiratory heating module is used for heating the gas in the heating unit according to the heating current, detecting the temperature of the gas in the respiratory heating module, and inputting the temperature signal into the input end of the short circuit protection module; The short circuit protection module is used to collect the temperature signal in the respiratory heating module when the respiratory heating module is in normal operation, and output the temperature signal to the temperature signal collecting end of the microcomputer, and cut off the short circuit current when the short circuit protection module is short circuited; A breathing circuit short circuit protection circuit characterized in that the current detection end and signal control end of the microcontroller are connected to the heating control and short circuit protection module, the temperature detection end of the microcontroller is connected to the output end of the short circuit protection module, and the microcontroller is used to receive the heating current and output a heating control signal to the heating control and short circuit protection module, and further receive the temperature signal and output the temperature signal to a higher-level computer.
2. the short circuit protection module comprises a first operational amplifier, a first resistor, a second resistor, a first transistor, a first capacitor, and a first recoverable fuse; The output end of the first operational amplifier is connected to the first end of the first resistor, the positive end of the power supply of the first operational amplifier is connected to a first power supply voltage, the negative end of the power supply of the first operational amplifier is grounded, the inverting input end of the first operational amplifier is connected to the output end of the first operational amplifier, the positive phase input end of the first operational amplifier is connected to one end of the first recoverable fuse, the first end of the second resistor is connected to the cathode of the first transistor and a common terminal of one end of the first capacitor, the second end of the second resistor is connected to the first power supply voltage, the second end of the first resistor is connected to a temperature detection end of the microcontroller, the other end of the first recoverable fuse is connected to the respiratory heating module, the anode of the first transistor is connected to the respiratory heating module, and the other end of the first capacitor and the common terminal of the anode of the first transistor are grounded.
3. The respiratory circuit short circuit protection circuit according to claim 1, further comprising a filter module, one end of the filter module being connected to the first power supply voltage and the other end being connected to the short circuit protection module, for reducing ripple and interference noise in the first power supply voltage and providing a stable DC output.
4. The heating control and short circuit protection module includes a short circuit protection unit and a heating control unit; One end of the short circuit protection unit is connected to a second power supply voltage, and the other end of the short circuit protection unit is connected to the respiratory heating module, and the short circuit protection unit is used to cut off the connection between the second power supply voltage and the respiratory heating module when a short circuit occurs; The respiratory circuit short circuit protection circuit of claim 1, characterized in that one end of the heating control unit is connected to the respiratory heating module and the other end is grounded, and the heating control unit is connected to the current detection end and signal control end of the microcontroller, and is used to receive a heating control signal from the microcontroller and control the heating current flowing through the respiratory heating module.
5. The respiratory circuit short circuit protection circuit of claim 4, characterized in that the respiratory heating module includes a temperature sensor and a heating device, one end of the temperature sensor is connected to the first input end of the short circuit protection module, and the other end of the temperature sensor and the second input end of the short circuit protection module are grounded and used to detect the connection between the heating device and the heating control and short circuit protection module.
6. The respiratory circuit short circuit protection circuit according to claim 3, characterized in that the filter module includes a second capacitor and a third capacitor, one end of the second capacitor and one end of the third capacitor are connected to the first power supply voltage and the short circuit protection module, and the other end of the second capacitor and the other end of the third capacitor are grounded.
7. The respiratory circuit short circuit protection circuit of claim 4, characterized in that the short circuit protection unit includes a second recoverable fuse, one end of the second recoverable fuse is connected to a second power supply voltage, and the other end of the second recoverable fuse is connected to the respiratory heating module.
8. the heating control unit includes a first field effect tube, a third resistor and a fourth resistor; The respiratory circuit short circuit protection circuit according to claim 4, characterized in that the gate of the first field effect tube is connected to one end of the third resistor, the drain of the first field effect tube is connected to one end of the fourth resistor, the source of the first field effect tube is connected to the respiratory heating module, the other end of the third resistor and the source of the first field effect tube are respectively connected to the microcomputer, and the other end of the fourth resistor is grounded.
9. 3. The breathing circuit short circuit protection circuit of claim 2, wherein the first transistor is an avalanche breakdown diode.
10. A breathing apparatus comprising a breathing device, a circuit, and a breathing circuit short circuit protection circuit according to any one of claims 1 to 9.