Breathing circuit short-circuit protection circuit and breathing device

Abstract

The utility model discloses a breathing circuit short-circuit protection circuit and a breathing device. The breathing circuit short-circuit protection circuit comprises a short-circuit protection module, a breathing heating module, a heating control and short-circuit protection module and a single chip microcomputer. The heating control and short-circuit protection module is connected with the breathing heating module, the breathing heating module is electrically connected with the heating control and short-circuit protection module and the short-circuit protection module, and a current detection end and a signal control end of the single chip microcomputer are connected with the heating control and short-circuit protection module. The temperature detection end of the single-chip microcomputer is connected with the output end of the short-circuit protection module, the temperature detection end of the single-chip microcomputer is connected with the output end of the short-circuit protection module, and the temperature detection end of the single-chip microcomputer is connected with the output end of the short-circuit protection module. The self-protection of the breathing device is realized when the circuit at any two pins in the loop is short-circuited, the maintenance is easy, and the use safety is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to medical instrument technical field especially, and it relates to a kind of breathing circuit short circuit protection circuit and breathing device. BACKGROUND

[0002] In the field of medical devices, the existing breathing equipment delivers heated gas to patients through a circuit and receives gas from patients, which helps to reduce the probability of patient infection and tissue damage. Among them, the circuit with heating wire generally integrates a temperature sensor (Negative Temperature Coefficient, NTC). Specifically, one end of the circuit with heating wire is connected to the patient's breathing port, and the other end is connected to the breathing host. It outputs the appropriate heating temperature for the breathing pipeline to heat and provides the appropriate temperature for the user. The heating wire in the circuit can maintain the temperature and humidity of the gas and reduce the condensate water. In the breathing equipment with heating wire, the inside of the circuit is often in a high-temperature and high-humidity environment, and the accumulated condensate water has the risk of seepage, which may cause short circuit between internal connections of various lines. When short circuit occurs between the heating wire line and the temperature sensor line, it is easy to damage the internal devices of the machine, such as the fuse on the printed circuit board assembly (PCBA), the IO port of the MCU, etc. It damages the precision equipment and causes additional maintenance costs. And the circuit burn in the breathing equipment may produce sparks and cause fire.

[0003] Therefore, the prior art still needs to be improved and developed. INVENTION CONTENTS

[0004] In view of the above shortcomings of the prior art, the purpose of the present utility model is to provide a breathing circuit short circuit protection circuit and breathing device to solve the problem that the internal devices of the machine are easily damaged when the breathing equipment is short-circuited, and the components in the circuit need to be frequently replaced, causing additional maintenance costs.

[0005] The technical solution of the utility model is as follows:

[0006] A breathing circuit short circuit protection circuit, comprising: a breathing circuit short circuit protection circuit, comprising: a short circuit protection module, a breathing heating module, a heating control and short circuit protection module, and a single-chip microcomputer;

[0007] The heating control and short circuit protection module is connected with the breathing heating module. The heating control and short circuit protection module is used for receiving the heating control signal output by the single-chip microcomputer when the breathing heating module is working normally, adjusting the heating current of the breathing heating module, feeding back the heating current to the single-chip microcomputer, and cutting off the short circuit current when the heating control and short circuit protection module is short-circuited;

[0008] The breathing heating module is electrically connected with the heating control and short circuit protection module and the short circuit protection module respectively, and is used for heating the gas in the heating unit according to the heating current, and is used for detecting the temperature of the gas in the breathing heating module and inputting the temperature signal to the input end of the short circuit protection module;

[0009] The short circuit protection module is used for collecting the temperature signal in the breathing heating module when the breathing heating module works normally, outputting the temperature signal to the temperature signal collection end of the single-chip microcomputer, and cutting off the short circuit current when the short circuit protection module is short-circuited.

[0010] The current detection end and the signal control end of the single-chip microcomputer are connected with the heating control and short circuit protection module, the temperature detection end of the single-chip microcomputer is connected with the output end of the short circuit protection module, the single-chip microcomputer is used for receiving the heating current and outputting the heating control signal to the heating control and short circuit protection module, and is also used for receiving the temperature signal and outputting the temperature signal to the upper computer.

[0011] Further settings of the utility model, the short circuit protection module includes: first operational amplifier, first resistance, second resistance, first transistor, first capacitor and first recoverable fuse;

[0012] The output end of the first operational amplifier is connected with the first end of the first resistance, the power positive end of the first operational amplifier is connected with the first power voltage, the power negative end of the first operational amplifier is grounded, the inverse input end of the first operational amplifier is connected with the output end of the first operational amplifier, and the noninverting input end of the first operational amplifier is connected with one end of the first recoverable fuse;The first end of the second resistance is connected with the cathode of the first transistor and the common connection end of one end of the first capacitor, and the second end of the second resistance is connected with the first power voltage;The second end of the first resistance is connected with the temperature detection end of the single-chip microcomputer;The other end of the first recoverable fuse is connected with the breathing heating module, the anode of the first transistor is connected with the breathing heating module, and the other end of the first capacitor is grounded with the common connection end of the anode of the first transistor.

[0013] Further settings of the utility model further include a filtering module;One end of the filtering module is connected with the first power voltage, the other end is connected with the short circuit protection module, is used for reducing the ripple and interference noise in the first power voltage, and provides stable DC output.

[0014] Further settings of the utility model, the heating control and short circuit protection module includes a short circuit protection unit and a heating control unit;

[0015] One end of the short-circuit protection unit is connected with the second power supply voltage, and the other end of the short-circuit protection unit is connected with the breathing heating module, and the short-circuit protection unit is used for disconnecting the connection between the second power supply voltage and the breathing heating module when a short circuit occurs.

[0016] One end of the heating control unit is connected with the breathing heating module, and the other end is grounded, the heating control unit is connected with the current detection end and the signal control end of the single-chip microcomputer, and is used for receiving the heating control signal from the single-chip microcomputer and controlling the heating current flowing through the breathing heating module.

[0017] Further, the breathing heating module comprises a temperature sensor and a heating device, one end of the temperature sensor is connected with the first input end of the short-circuit protection module, and the other end of the temperature sensor is grounded with the second input end of the short-circuit protection module, and is used for detecting the connection between the heating device and the heating control and short-circuit protection module.

[0018] Further, the filter module comprises a second capacitor and a third capacitor, one end of the second capacitor and one end of the third capacitor are connected with 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.

[0019] Further, the short-circuit protection unit comprises a second recoverable fuse, one end of the second recoverable fuse is connected with the second power supply voltage, and the other end of the second recoverable fuse is connected with the breathing heating module.

[0020] Further, the heating control unit comprises a first field effect tube, a third resistor and a fourth resistor, wherein,

[0021] The gate of the first field effect tube is connected with one end of the third resistor, the drain of the first field effect tube is connected with one end of the fourth resistor, the source of the first field effect tube is connected with the breathing heating module, the other end of the third resistor and the source of the first field effect tube are respectively connected with the single-chip microcomputer, and the other end of the fourth resistor is grounded.

[0022] Further, the first transistor is an avalanche breakdown diode.

[0023] Further, the utility model also provides a kind of breathing device, it includes breathing apparatus, circuit and the breathing circuit short-circuit protection circuit as described above.

[0024] The utility model discloses a kind of breathing circuit short-circuit protection circuit and breathing device, comprising: short-circuit protection module, breathing heating module, heating control and short-circuit protection module and single-chip microcontroller;The heating control and short-circuit protection module are connected with the breathing heating module, the heating control and short-circuit protection module are used to receive the heating control signal output by the single-chip microcontroller when the breathing heating module works normally, adjust the heating current of the breathing heating module, heating current is fed back to the single-chip microcontroller, and are used to cut off short-circuit current when the heating control and short-circuit protection module short-circuit;The breathing heating module is electrically connected with the heating control and short-circuit protection module and the short-circuit protection module respectively, and the breathing heating module is used to heat gas in heating unit according to heating current, and is used to detect the temperature of gas in the breathing heating module and input temperature signal to the input end of the short-circuit protection module;The short-circuit protection module is used to collect temperature signal in the breathing heating module when the breathing heating module works normally, output temperature signal to the temperature signal acquisition end of the single-chip microcontroller, and is used to cut off short-circuit current when the short-circuit protection module short-circuit;The current detection end and signal control end of the single-chip microcontroller are connected with the heating control and short-circuit protection module, the temperature detection end of the single-chip microcontroller is connected with the output end of the short-circuit protection module, and the single-chip microcontroller is used to receive the heating current and output heating control signal to the heating control and short-circuit protection module, and is also used to receive the temperature signal and output temperature signal to host computer.The utility model uses recoverable fuse as short-circuit protection device in heating device circuit, and designs short-circuit protection module on temperature signal detection circuit, replaces the technical scheme that short-circuit protection device needs to be replaced repeatedly in prior art, realizes the self-protection of breathing device when the circuit of any two pins in loop short-circuit, host computer and circuit can restore normal state, only need to replace loop to work, easy to maintain, improve the security when using. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical scheme in the embodiments of the utility model or prior art, the following will briefly introduce the drawings needed to be used in embodiment or prior art description, obviously, the drawings in the following description are only some embodiments of the utility model, and for ordinary person in the art, other drawings can be obtained according to the structure shown in these drawings without creating labor.

[0026] Figure 1 It is the principle block diagram of a kind of breathing circuit short-circuit protection circuit provided by the utility model.

[0027] Figure 2 It is the circuit structure diagram of a kind of breathing circuit short-circuit protection circuit provided in the utility model.

[0028] The same reference signs in the drawings indicate the same components: 100, short circuit protection module; 200, breathing heating module; 300, heating control and short circuit protection module; 400, single-chip microcomputer; 500, filtering module. DETAILED DESCRIPTION

[0029] The utility model provides a kind of breathing circuit short circuit protection circuit and breathing device, to make the purpose, technical scheme and effect of the utility model more clear, definite, the following referring to drawing and taking example to the utility model further detailed explanation.It should be understood that the specific embodiments described herein are merely intended to explain the utility model, and not intended to limit the utility model.

[0030] In the embodiments and the scope of the application, unless the article is specifically limited in the text, "a", "an", "said" and "the" can also include plural forms.If the description of "first", "second" and the like is involved in the embodiments of the utility model, the description of "first", "second" and the like is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features.Therefore, the features limited by "first", "second" can be explicitly or implicitly included at least one feature.

[0031] It should be further understood that the phrase "comprising" used in the specification of the utility model means that the features, integers, steps, operations, elements and / or components exist, but does not exclude the existence or addition of one or more other features, integers, steps, operations, elements, components and / or their groups.It should be understood that when we say that an element is "connected" or "coupled" to another element, it can be directly connected or coupled to other elements, or there can be intermediate elements.In addition, "connection" or "coupling" used herein can include wireless connection or wireless coupling.The phrase "and / or" used herein includes all or any unit and all combinations of the associated listed items.

[0032] Those skilled in the art can understand that, unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as that generally understood by ordinary skilled persons in the field to which the utility model belongs.It should also be understood that terms such as those defined in general dictionaries should be understood as having meanings consistent with those in the prior art, and unless specifically defined as here, should not be interpreted as idealized or overly formal.

[0033] In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of ordinary skilled persons in the art, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, and is not within the protection scope required by the utility model.

[0034] Referring to Figure 1 In the partial preferred embodiments of the utility model, a breathing circuit short circuit protection circuit is provided, which comprises a short circuit protection module 100, a breathing heating module 200, a heating control and short circuit protection module 300 and a single-chip microcomputer 400. The heating control and short circuit protection module 300 is connected with the breathing heating module 200. The heating control and short circuit protection module 300 is used for receiving the heating control signal output by the single-chip microcomputer 400 when the breathing heating module 200 is working normally, adjusting the heating current of the breathing heating module 200, feeding back the heating current to the single-chip microcomputer 400, and cutting off the short circuit current when the heating control and short circuit protection module 300 occurs short circuit. The breathing heating module 200 is electrically connected with the heating control and short circuit protection module 300 and the short circuit protection module 100 respectively. The breathing heating module 200 is used for heating the gas in the heating unit according to the heating current, and detecting the temperature of the gas in the breathing heating module 200 and inputting the temperature signal to the input end of the short circuit protection module 100. The short circuit protection module 100 is used for collecting the temperature signal in the breathing heating module 200 when the breathing heating module is working normally, outputting the temperature signal to the temperature signal collection end of the single-chip microcomputer 400, and cutting off the short circuit current when the short circuit protection module occurs short circuit. The current detection end and signal control end of the single-chip microcomputer 400 are connected with the heating control and short circuit protection module 300. The temperature detection end of the single-chip microcomputer 400 is connected with the output end of the short circuit protection module 100. The single-chip microcomputer 400 is used for receiving the heating current and outputting the heating control signal to the heating control and short circuit protection module 300. The heating control signal is a PWM signal. The heating control and short circuit protection module 300 is also used for receiving the temperature signal and outputting the temperature signal to the upper computer.

[0035] Specifically, when working normally, the heating control and short circuit protection module 300 is connected with the breathing heating module 200, and controls the heating current input to the breathing heating module 200, thereby controlling the heating degree of the breathing heating module 200. The breathing heating module 200 is in contact with the gas, heats the gas, and simultaneously detects the real-time temperature of the gas in the current environment, and generates a temperature detection signal. At the same time, the temperature of the breathing circuit short circuit protection circuit when working normally is regarded as room temperature. The short circuit protection module 100 can be regarded as a wire. The temperature detection end of the single-chip microcomputer 400 is connected with the breathing heating module 200, and collects the temperature signal output by the breathing heating module 200.

[0036] When a short circuit occurs, the breathing heating module 200 does not participate in voltage division because no current flows through it. Since the working 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 single-chip microcomputer 400 can bear, at this time, the short circuit current in the circuit is much larger than the working current under normal circumstances, which can cause the electronic components, especially precision devices such as single-chip microcomputers, to burn out. In some cases, the short circuit protection module 100 and the single-chip microcomputer 400 can be short-circuited with the heating control and short circuit protection module 300. Here, the second end and the third end of the breathing heating module are short-circuited, that is, the short circuit protection module 100 and the single-chip microcomputer 400 circuit are connected with the voltage input end of the heating control and short circuit protection module 300. At this time, the breathing heating module is short-circuited, the input end of the short circuit protection module 100 is the working voltage of the heating control and short circuit protection module 300, the short circuit protection module 100 is used to timely cut off the connection between the breathing heating module 200 and the heating control and short circuit protection module 300, and the single-chip microcomputer 400 is protected from short circuit to prevent the working voltage of the heating control and short circuit protection module 300 from flowing into the input end of the single-chip microcomputer 400, thereby damaging the single-chip microcomputer 400. Thus, when a short circuit occurs, the host and other circuits can return to normal state, and only the circuit needs to be replaced, without the need for maintenance and replacement, making the breathing circuit maintenance more convenient and reliable, reducing maintenance costs, and improving safety during use.

[0037] Further, please refer to Figure 2 , the short circuit protection module 100 comprises 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 with the first end of the first resistor, the positive power supply end of the first operational amplifier is connected with the first power supply voltage, the negative power supply end of the first operational amplifier is grounded, the inverting input end of the first operational amplifier is connected with the output end of the first operational amplifier, and the non-inverting input end of the first operational amplifier is connected with one end of the first recoverable fuse; the first end of the second resistor is connected with the cathode of the first transistor and the common connection end of one end of the first capacitor, and the second end of the second resistor is connected with the first power supply voltage; the second end of the first resistor is connected with the temperature detection end of the single-chip microcomputer; the other end of the first recoverable fuse is connected with the breathing heating module, the anode of the first transistor is connected with the breathing heating module, and the other end of the first capacitor is grounded.

[0038] Specifically, the first power voltage is 3.3V. The recoverable fuse generates heat when abnormal overcurrent passes through, which makes the internal resistance of the recoverable fuse rise and reduce the abnormal overcurrent; when the abnormal overcurrent fault is cleared, the conductive channel in the recoverable fuse recovers and returns to the original low resistance state. The input end of the short circuit protection module 100 is connected with the breathing heating module 200, when the temperature of the gas in the loop changes, the resistance value of the temperature sensor itself will also change, at this time, the voltage at the output end of the temperature sensor is the temperature signal. When the breathing heating module works normally, the first fuse works normally, and the first fuse is regarded as a wire, the non-inverting input end of the first operational amplifier U1B is equivalent to being directly connected with the breathing heating module 200, and the inverting input end of the first operational amplifier U1B is connected with the output end of the first operational amplifier U1B. At this time, the first operational amplifier U1B is a voltage follower, the voltage at the output end of the first operational amplifier U1B follows the voltage change of the non-inverting input end of the first operational amplifier U1B, and the voltage at the temperature signal acquisition end of the single-chip microcomputer 400 is the temperature signal output by the temperature sensor when working normally. The single-chip microcomputer 400 receives the temperature signal and saves it in the single-chip microcomputer register and transmits it to the upper computer, and displays to the user, so that the temperature monitoring of the breathing gas is realized. Optionally, the single-chip microcomputer 400 can process and package the data before outputting the temperature signal, and the transmission mode can adopt wired transmission or wireless transmission, and the specific implementation mode of the temperature signal transmission in the utility model is not limited.

[0039] When the short circuit protection module 100 is short-circuited with other lines, the first transistor D1 clamps the voltage value of the positive input end of the first operational amplifier U1B at its tube voltage drop. The first transistor D1 is an avalanche breakdown diode, so the voltage of the positive input end of the first operational amplifier U1B is limited to 7V for a certain period of time, which is used to protect the circuit from the impact of transient high voltage surges. The first transistor D1 prevents the input voltage of the short circuit protection module 100 from being directly loaded to the positive input end of the first operational amplifier U1B, thereby causing the first operational amplifier U1B to be damaged, by forming a voltage stabilizing circuit. When a short circuit occurs in the circuit, the first recoverable fuse F1 rapidly increases the impedance to limit abnormal current and enters an open circuit state before the first transistor D1 is damaged, thereby preventing the first transistor D1 from being broken down due to excessive voltage across its terminals in a short circuit state and protecting the first operational amplifier U1B and the single-chip microcomputer 400 behind it. When the short circuit state is removed, the first recoverable fuse F1 resumes the conduction state and will not be damaged due to the short circuit state. The first operational amplifier U1B, as the positive input end and output end of the voltage follower, has equal voltages, which presents a high resistance state, equivalent to an open circuit. 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 protect the single-chip microcomputer 400, and at the same time, the elements inside the short circuit protection module 100 are not damaged due to the short circuit, which will not affect the subsequent use of the machine. As long as the breathing heating module that has a short circuit is replaced, the machine can be used again.

[0040] In some other preferred embodiments, the power supply positive end of the first operational amplifier U1B is also connected to a filtering module 500; one end of the filtering module 500 is connected to the first power supply voltage, and the other end is connected to the short circuit protection module 100. The filtering 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 100, and the other end of the second capacitor C2 and the other end of the third capacitor C3 are grounded, which is used to reduce the ripple and interference noise in the first power supply voltage, provide stable DC output, reduce the interference of interference noise on the signal detection of the short circuit protection circuit, and make the power supply signal input to the first operational amplifier U1B more stable.

[0041] Further, the heating control and short circuit protection module 300 comprises a short circuit protection unit 310 and a heating control unit 320. One end of the short circuit protection unit 310 is connected with the second power supply voltage, and the other end of the short circuit protection unit 310 is connected with the breathing heating module 200. The short circuit protection unit 310 is used to disconnect the connection between the second power supply voltage and the breathing heating module 200 when a short circuit occurs. One end of the heating control unit 320 is connected with the breathing heating module 200, and the other end is grounded. The heating control unit 320 is connected with the current detection end and the signal control end of the single-chip microcomputer, used to receive the heating control signal from the single-chip microcomputer and control the heating current flowing through the breathing heating module 200.

[0042] The short circuit protection unit 310 comprises a second recoverable fuse F2. One end of the second recoverable fuse F2 is connected with the second power supply voltage, and the other end of the second recoverable fuse F2 is connected with the breathing heating module 200. The heating control unit 320 comprises a first field effect transistor Q1, a third resistor R3 and a fourth resistor R4. The gate of the first field effect transistor Q1 is connected with one end of the third resistor R3. The drain of the first field effect transistor is connected with one end of the fourth resistor R4. The source of the first field effect transistor is connected with the breathing heating module. The other end of the third resistor R3 and the source of the first field effect transistor are respectively connected with the single-chip microcomputer. The other end of the fourth resistor R4 is grounded. The first field effect transistor Q1 is an N-channel field effect transistor. The first field effect transistor Q1 controls the heating current flowing through the breathing heating module through the duty ratio of the heating control signal at the gate. The heating control signal is a PWM signal. When the output signal of the single-chip microcomputer 400 is greater than the gate voltage of the first field effect transistor Q1, the first field effect transistor Q1 is turned on. When the output signal of the single-chip microcomputer 400 is less than the gate voltage of the first field effect transistor Q1, the first field effect transistor Q1 is turned off.

[0043] Specifically, the first power supply voltage is 3.3V, and the second power supply voltage is 24V. The first and second self-resetting fuses are polymeric positive temperature coefficient (PPTC) fuses. When an abnormal overcurrent passes through the self-resetting fuse, the heat generated causes the polymeric matrix material to expand, and the conductive particles outside the polymeric matrix material separate, thereby cutting off the conductive path of the self-resetting fuse and increasing the resistance of the self-resetting fuse, thereby reducing the abnormal overcurrent, cutting off the circuit, and playing a circuit protection role. When the abnormal overcurrent fault is cleared, the polymeric matrix material of the self-resetting fuse shrinks to its original shape, re-connecting the conductive particles, and the conductive path is automatically restored, and the resistance of the self-resetting fuse returns to its original low resistance state. Compared with traditional fuse-type fuses, the self-resetting fuses do not need to be replaced after a short circuit, greatly saving the use cost, and can realize multiple short circuit protection functions.

[0044] When the breathing heating module is working normally, the second self-resetting fuse F2 in the short circuit protection unit 310 is turned on, the first end of the heating device in the breathing heating module is connected to the short circuit protection unit 310 through the breathing heating module 200, and the second end of the heating device is connected to the heating control unit 320 through the breathing heating module 200. At this time, the current of the heating device circuit flows through the short circuit protection unit 310, the breathing heating module 200, the heating device, and then flows through the breathing heating module 200 and the heating control unit 320 and is grounded GND. The current of the single-chip microcomputer 400 controls the duty cycle of the heating control signal output, controls the turn-on and turn-off of the first field effect transistor Q1, and further controls the temperature of the heating device.

[0045] In further embodiments of some preferred embodiments, as shown in Figure 2 The breathing heating module 200 is electrically connected to the short circuit protection module 100 and the heating control and short circuit protection module 300 through a six-pin round jumper seat, and the other end of the six-pin round jumper seat is electrically connected to the breathing heating module 200. The breathing heating module 200 includes a temperature sensor (not shown in the figure) and a heating device (not shown in the figure). 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 is grounded to the second input end of the short circuit protection module, for detecting the temperature of the gas in the breathing heating module and inputting the temperature signal to the input end of the short circuit protection module. The two ends of the heating device are respectively connected to the heating control and short circuit protection module, for heating the gas in the heating unit according to the heating current.

[0046] The pins in the jumper seat are electrically connected with the breathing heating module through data lines. The first end of the breathing heating module 200 is connected with the heating control unit 320, the second end of the breathing heating module 200 is connected with the heating short-circuit protection module 100, the third end of the breathing heating module 200 is connected with the short-circuit protection module 100, and the fourth end of the breathing heating module 200 is grounded. The second end and the third end of the breathing heating module 200 can be connected with other medical instrument related electronic elements. In some preferred embodiments of the present application, the idle port of the breathing heating module can also be connected with the temperature sensor circuit, and the connection relationship of the circuit is the same as that of the short-circuit protection module 100-single-chip microcomputer 400 circuit, which will not be repeated here.

[0047] Further, the temperature detection end TEMP_AD of the single-chip microcomputer 400 is connected with the short-circuit protection module 100, and the current detection end CURR and the signal control end PWM of the single-chip microcomputer 400 are respectively connected with the heating control and short-circuit protection module 300. Specifically, the temperature detection end TEMP_AD of the single-chip microcomputer 400 is connected with the output end of the first operational amplifier U1B, the current detection end of the single-chip microcomputer 400 is connected with the source of the first field effect tube Q1, and the signal control end PWM of the single-chip microcomputer 400 is connected with the gate of the first field effect tube Q1. The single-chip microcomputer 400 is used for receiving the heating device current signal at the current detection end CURR and the temperature signal at the temperature detection end TEMP_AD, and outputting the heating control signal for controlling the heating control and short-circuit protection module 300.

[0048] Specifically, the I / O port of the single-chip microcomputer 400 must have ADC function, which can convert analog signals into digital signals. The single-chip microcomputer 400 is used for receiving the heating wire current signal at the current detection end CURR and outputting the corresponding short-circuit condition, and simultaneously receiving the temperature signal at the temperature detection end TEMP_AD and outputting the heating control signal for controlling the heating control and short-circuit protection module 300. In some preferred embodiments, the single-chip microcomputer 400 is preferably an STM32F407ZGTx chip.

[0049] Specifically, one end of the short-circuit protection unit 310 is connected with the second power supply voltage, the other end of the short-circuit protection unit 310 is connected with one end of the heating device through the second pin of the circular jumper seat in the breathing heating module 200, one end of the heating control unit 320 is connected with the other end of the heating device through the second pin of the circular jumper seat in the breathing heating module 200, the short-circuit protection unit 310, the heating device and the heating control unit 320 constitute a heating branch. The first input end of the short-circuit protection module 100 is connected with one end of the temperature sensor through the third pin of the circular jumper seat in the breathing heating module 200, the second input end of the short-circuit protection module 100 is connected with the other end of the temperature sensor through the third pin of the circular jumper seat in the breathing heating module 200, the short-circuit protection module 100 and the temperature sensor constitute a temperature monitoring branch.

[0050] When the breathing heating module works normally, the first power supply voltage supplies power for the short-circuit protection module 100 and the temperature sensor, when the temperature in the breathing heating module 200 changes, the resistance of the temperature sensor changes accordingly, the voltage division value of the second resistance R2 and the temperature sensor changes, and the output voltage of the first operational amplifier as a voltage follower changes. At this time, the single-chip microcomputer stores the sampling voltage value of the temperature detection end into the register, and transmits the temperature signal to the upper computer, and displays the temperature value of the gas in the breathing heating module 200 at the current time to the user. At the same time, the heating device in the breathing heating module 200 is supplied with power by the second power supply voltage of 24V, at this time, the short-circuit protection unit 310, the heating device and the heating control unit 320 are connected in series, 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 with the signal control end PWM of the single-chip microcomputer 400, by adjusting the duty cycle of the heating control signal, the on-off of the first field effect tube Q1 is controlled, and then the heating current flowing through the heating device in the breathing heating module 200 is controlled, and the heating state of the breathing heating module is controlled.

[0051] When the short circuit occurs in the breathing heating module 200, the short circuit occurs between any two pins, the single-chip microcomputer 400 can judge the short circuit between the pins in the breathing heating module 200 through the current detection end CURR, and the short circuit protection and judgment method is as follows:

[0052] When the first end and the second end, the fourth end and the second end of the breathing heating module 200 are short-circuited, the circuit is short-circuited, at this time, the second recoverable fuse F2 is regarded as open circuit, the second power supply voltage is disconnected with the circuit. When the short-circuit state is removed, the second recoverable fuse F2 returns to the normal working state.

[0053] When the first end and the fourth end of the breathing heating module 200 are short-circuited, there is no power supply in the circuit, the circuit will not be damaged by short-circuit current, at this time, the current detection end CURR of the single-chip microcomputer 400 has no current, and is not controlled by the signal control end PWM of the single-chip microcomputer 400. The single-chip microcomputer 400 can know that the fourth end and the first end of the breathing heating module 200 are short-circuited through the signal control of the current detection end CURR and the signal control end PWM.

[0054] When the fourth end and the third end of the breathing heating module 200 are short-circuited, the positive input end of the first operational amplifier U1B is grounded, the first operational amplifier U1B follows the voltage of the positive input end, and the voltage value of the first resistor R1 is also 0V. At this time, the voltage detected by the temperature detection end TEMP_AD of the single-chip microcomputer 400 is 0V. The single-chip microcomputer 400 can know that the fourth end and the third end of the breathing heating module 200 are short-circuited through the voltage value of the temperature detection end TEMP_AD.

[0055] When the second end and the third end, the first end and the third end of the breathing 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 disconnected, preventing the surge voltage from damaging the circuit. Specifically, the first transistor D1 in the circuit limits the voltage to about 7V of its tube voltage drop. Without this device, the second power supply voltage 24V will be directly applied at the positive input terminal of the first operational amplifier U1B, damaging the first operational amplifier U1B. At the same time, the first operational amplifier U1B samples the temperature signal by voltage following. The voltage at the positive input terminal and the output terminal of the voltage follower is equal, and the first operational amplifier U1B presents a high resistance state, equivalent to an open circuit, while limiting the voltage to 3.3V, preventing the 7V clamping voltage at the first transistor D1 from being directly applied to the I / O port of the temperature detection terminal TEMP_AD of the single-chip microcomputer 400, damaging the I / O port of the single-chip microcomputer 400. At this time, the voltage across the first transistor D1 is too high, and the first transistor D1 as an avalanche breakdown diode will also be short-circuited, and the internal current will increase sharply, thereby damaging the first transistor D1. Before the first transistor D1 is damaged due to short-circuit, the first recoverable fuse F1 realizes current limiting disconnection for the circuit, and the resistance rapidly increases until the first recoverable fuse F1 is equivalent to an open circuit, protecting the electronic components in the short-circuit protection module 100 and the single-chip microcomputer 400.

[0056] In summary, when different types of short circuits occur in the breathing heating module, each electronic component in the circuit is protected from short circuits. Only the breathing heating module that has a short circuit needs to be replaced during maintenance to resolve the circuit open fault. After the short circuit fault is resolved, the first recoverable fuse F1 automatically recovers to the on state. When a short circuit occurs in the circuit at any two pins, only the circuit needs to be replaced. The host and the circuit can both return to normal state, making it easy to maintain and improving safety during use.

[0057] In addition, based on the same utility model concept, the utility model also provides a breathing device with short circuit protection function, including breathing apparatus, circuit and breathing circuit short circuit protection circuit as described above, the breathing apparatus can be anesthesia equipment or breathing equipment, at least one line in the circuit is connected with temperature sensor and heating wire respectively, is suitable for patient and anesthesia equipment and breathing equipment connection, provides the channel for patient inhale and exhale gas. Specifically, the breathing heating module of breathing circuit short circuit protection circuit is arranged in the circuit, and is electrically connected with other modules of breathing circuit short circuit protection circuit through circular jumper seat. The temperature sensor is connected with the short circuit protection module 100 through the breathing heating module 200, and is used for receiving the heating control signal output by the heating control and short circuit protection module 300. The heating device is connected with the heating control and short circuit protection module 300 through the breathing heating module 200, and adjusts the air temperature in the circuit according to the heating control signal, to reduce the condensation of moisture.

[0058] Specifically, the heating device takes the heating wire as an example, which is uniformly distributed in the whole circuit in a spiral manner, for increasing the heat transfer area and improving the air heating efficiency. Similarly, the temperature sensor is electrically connected with the line in the circuit, which is used for detecting the temperature of the air in the circuit and outputting a temperature signal to the breathing heating module 200. The breathing heating module 200 outputs the temperature signal to the single-chip microcomputer 400. The single-chip microcomputer 400 receives the temperature signal, and then obtains the air temperature in the circuit at this time through 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 with the heating device through the breathing heating module 200. 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 the corresponding heating signal, so as to control the heating power of the heating device through the heating signal, and realize the feedback regulation of the air temperature in the circuit. In specific implementation, the connection mode and quantity of the breathing heating module 200 and the line in the circuit can be changed according to the actual production and use process, which is not limited here.

[0059] The utility model discloses a breathing circuit short circuit protection circuit and breathing device, its beneficial effect lies in: through using recoverable fuse as short circuit protection device in heating device circuit, and designing short circuit protection module on temperature signal detection circuit, replaces the technical scheme of repeatedly replacing short circuit protection device in prior art, realizes the self -protection of breathing device when the circuit of arbitrary two pins in the circuit short circuit, host computer and circuit can restore normal state, only need to replace the circuit and can work, easy to maintain, improves the security when using.

[0060] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0061] It should be noted that the specific structure and working principle of the present application are introduced by taking the breathing circuit short circuit protection circuit and the breathing device with heating function and short circuit protection function as an example, but the application of the present application is not limited to the breathing circuit short circuit protection circuit and the breathing device with heating function and short circuit protection function, and can also be applied to other similar devices.

[0062] It should be understood that the present application is not limited to the precise structures described above and shown in the drawings, and various modifications and changes can be made without departing from the scope thereof. The scope of the present application is only limited by the appended claims.

[0063] It should be understood that the application of the present application is not limited to the above examples, and can be improved or changed according to the above description for those skilled in the art, and all these improvements and changes shall belong to the protection scope of the appended claims of the present application.

Claims

1. A respiratory circuit short circuit protection circuit, characterized by, The application relates to a short-circuit protection module, a breathing heating module, a heating control and short-circuit protection module and a single-chip microcomputer. The heating control and short-circuit protection module is connected with the breathing heating module, is used for receiving a heating control signal output by the single-chip microcomputer when the breathing heating module normally works, adjusting a heating current of the breathing heating module, feeding back the heating current to the single-chip microcomputer and cutting off a short-circuit current when the heating control and short-circuit protection module is short-circuited. The breathing heating module is electrically connected with the heating control and short-circuit protection module and the short-circuit protection module respectively, is used for heating gas in a heating unit according to the heating current and is used for detecting the temperature of the gas in the breathing heating module and inputting a temperature signal to an input end of the short-circuit protection module. The short-circuit protection module is used for collecting the temperature signal in the breathing heating module when the breathing heating module normally works, outputting the temperature signal to a temperature signal collection end of the single-chip microcomputer and cutting 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 single-chip microcomputer are connected with the heating control and short-circuit protection module, the temperature detection end of the single-chip microcomputer is connected with the output end of the short-circuit protection module, the single-chip microcomputer is used for receiving the heating current and outputting the heating control signal to the heating control and short-circuit protection module and is also used for receiving the temperature signal and outputting the temperature signal to an upper computer. 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.

2. The breathing circuit occlusion protection circuit of claim 1, wherein, The output end of the first operational amplifier is connected with the first end of the first resistor, the power positive end of the first operational amplifier is connected with a first power voltage, the power negative end of the first operational amplifier is grounded, the inverting input end of the first operational amplifier is connected with the output end of the first operational amplifier, and the non-inverting input end of the first operational amplifier is connected with one end of the first recoverable fuse; the first end of the second resistor is connected with the cathode of the first transistor and the common connection end of one end of the first capacitor, the second end of the second resistor is connected with the first power voltage; the second end of the first resistor is connected with the temperature detection end of the single-chip microcomputer; the other end of the first recoverable fuse is connected with the breathing heating module, the anode of the first transistor is connected with the breathing heating module, and the other end of the first capacitor is grounded. The application further comprises a filtering module, one end of the filtering module is connected with the first power voltage, the other end of the filtering module is connected with the short-circuit protection module, the filtering module is used for reducing ripples and interference noises in the first power voltage and providing stable direct-current output.

3. The breathing circuit occlusion protection circuit of claim 1, wherein, The heating control and short-circuit protection module comprises a short-circuit protection unit and a heating control unit.

4. The breathing circuit occlusion protection circuit of claim 1, wherein, ​ One end of the short-circuit protection unit is connected with the second power supply voltage, and the other end of the short-circuit protection unit is connected with the breathing heating module, and the short-circuit protection unit is used for disconnecting the connection between the second power supply voltage and the breathing heating module when a short circuit occurs. One end of the heating control unit is connected with the breathing heating module, and the other end is grounded, and the heating control unit is connected with the current detection end and the signal control end of the single-chip microcomputer, and is used for receiving the heating control signal from the single-chip microcomputer and controlling the heating current flowing through the breathing heating module.

5. The breathing circuit occlusion protection circuit of claim 4, wherein, The breathing heating module comprises a temperature sensor and a heating device, one end of the temperature sensor is connected with the first input end of the short-circuit protection module, and the other end of the temperature sensor is grounded with the second input end of the short-circuit protection module, and is used for detecting the connection between the heating device and the heating control and short-circuit protection module.

6. The breathing circuit occlusion protection circuit of claim 3, wherein, The filter module comprises a second capacitor and a third capacitor, one end of the second capacitor and one end of the third capacitor are connected with 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 breathing circuit occlusion protection circuit of claim 4, wherein, The short-circuit protection unit comprises a second recoverable fuse, one end of the second recoverable fuse is connected with the second power supply voltage, and the other end of the second recoverable fuse is connected with the breathing heating module.

8. The breathing circuit occlusion protection circuit of claim 4, wherein, The heating control unit comprises a first field effect transistor, a third resistor and a fourth resistor; wherein, The gate of the first field effect transistor is connected with one end of the third resistor, the drain of the first field effect transistor and one end of the fourth resistor are connected, the source of the first field effect transistor is connected with the breathing heating module, the other end of the third resistor and the source of the first field effect transistor are respectively connected with the single-chip microcomputer, and the other end of the fourth resistor is grounded.

9. The breathing circuit occlusion protection circuit of claim 2, wherein, The first transistor is an avalanche breakdown diode.

10. A breathing apparatus characterized by The breathing circuit short-circuit protection circuit comprises a breathing apparatus, a circuit and the breathing circuit short-circuit protection circuit according to any one of claims 1-9.

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