Heating control circuit and breathing machine

Abstract

The utility model relates to the technical field of medical instruments, and provides a heating control circuit and a breathing machine. The heating control circuit comprises a humidifier heating state processing module, a humidifier heating state collecting module, a humidifier heating power adjusting module, a heating switching module, a breathing pipeline heating state processing module, a breathing pipeline heating power adjusting module and a breathing pipeline heating state collecting module. The heating switching module is used for controlling the heating mode of the breathing machine. According to the heating control circuit, the risk that the surface temperature of the circuit is too high due to the fact that a high-power power source is used for heating the humidifier and the breathing pipeline at the same time is avoided, the heating reliability of the breathing machine is improved, meanwhile, the heating control circuit monitors the heating temperature of the humidifier and the heating temperature of the breathing pipeline, and the principle that power is cut off if overheating is carried out is adopted; and the safety risk caused by over-high temperature in the use process of the breathing machine is further avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of medical devices, in particular to a heating control circuit and a ventilator. Background Art

[0002] The heating humidifier for a ventilator is connected in series at the inhalation end of the patient circuit of the ventilator, and plays a role in heating and humidifying the cold and dry gas sent out by the ventilator, which can effectively avoid discomfort such as dryness in the oral cavity, nasal cavity and throat during its use. At the same time, in order to prevent the heated and humidified air from condensing and affecting the use of the patient, an anti-condensation heating pipeline is generally used, and the air heated by the breathing pipeline is directly in contact with the patient to prevent the patient from having coughing symptoms. Therefore, humidifier heating and breathing pipeline heating play a very important role in the respiratory treatment of patients.

[0003] At present, heating the air by the humidifier and the breathing pipeline at the same time requires a power supply with a large power. This requires a high output power for the power supply system of the ventilator, and at the same time, corresponding heat dissipation treatment needs to be carried out for the phenomenon that the power supply system of the ventilator heats up due to excessive power. This increases the design difficulty and manufacturing cost, and there are certain safety risks. Summary of the Invention

[0004] The utility model provides a heating control circuit and a ventilator to solve the defects that the power supply system has a high output power requirement and there are safety risks caused by too high circuit temperature during the heating process of the humidifier and the breathing pipeline in the prior art, and improve the heating reliability of the ventilator.

[0005] The utility model provides a heating control circuit, including:

[0006] A humidifier heating state processing module, a humidifier heating state acquisition module, a humidifier heating power adjustment module, a heating switching module, a breathing pipeline heating state processing module, a breathing pipeline heating power adjustment module, and a breathing pipeline heating state acquisition module, wherein:

[0007] The humidifier heating power adjustment module is connected to the humidifier heating state processing module, and the humidifier heating state processing module is connected to the humidifier heating state acquisition module;

[0008] The breathing pipeline heating power adjustment module is connected to the breathing pipeline heating state processing module, and the breathing pipeline heating state processing module is connected to the breathing pipeline heating state acquisition module;

[0009] The heating switching module is connected to the humidifier heating power adjustment module, the humidifier heating state processing module, the breathing pipeline heating state processing module, and the breathing pipeline heating power adjustment module, and is configured to switch the heating mode of the ventilator according to the voltage comparison between the first voltage between the humidifier heating power adjustment module and the humidifier heating state processing module and the second voltage between the breathing pipeline heating state processing module and the breathing pipeline heating power adjustment module. If the first voltage is higher than the second voltage, the heating mode of the ventilator is humidifier heating; if the first voltage is lower than the second voltage, the heating mode of the ventilator is breathing pipeline heating.

[0010] According to a heating control circuit provided by the present invention, the heating switching module includes a diode D1, the first voltage is connected to the cathode of the diode D1, and the second voltage is connected to the anode of the diode D1.

[0011] According to a heating control circuit provided by the present invention, the humidifier heating state processing module includes a humidifier heating state detection unit, a heating temperature control unit, and a first driving unit. The heating resistance value collected by the humidifier heating state acquisition module is connected to the input end of the humidifier heating state detection unit for detecting the heating state of the humidifier. The input end of the heating temperature control unit is connected to the output end of the humidifier heating state detection unit for limiting the heating temperature of the humidifier. The input end of the first driving unit is connected to the output end of the heating temperature control unit for driving the humidifier to heat.

[0012] According to a heating control circuit provided by the present invention, the humidifier heating power adjustment module includes a resistor R1, a capacitor C1, a resistor R2, a diode D2, and an NPN transistor Q1. One end of the resistor R1 is connected to a PWM signal, and the other end is connected to one end of the capacitor C1. The other end of the capacitor C1 is respectively connected to the base of the NPN transistor Q1, one end of the resistor R2, and the cathode of the diode D2. The other end of the resistor R2 is grounded, the anode of the diode D2 is grounded, the emitter of the NPN transistor Q1 is grounded, and the collector of the NPN transistor Q1 is respectively connected to the humidifier heating state processing module and the heating switching module.

[0013] According to a heating control circuit provided by the present utility model, the first driving unit includes a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a resistor R8, an NPN transistor Q2, a PNP transistor Q3, an NMOS transistor U1, a PMOS transistor U2, a PMOS transistor U3, and a humidifier heating power supply. Among them, the output end of the heating temperature control unit is connected to the gate of the NMOS transistor U1. The source of the NMOS transistor U1 is grounded. The drain of the NMOS transistor U1 is connected to one end of the resistor R3, and the other end of the resistor R3 is connected to one end of the resistor R4. The other end of the resistor R4 is respectively connected to the source of the PMOS transistor U2 and the humidifier heating power supply. The gate of the PMOS transistor U2 is connected to one end of the resistor R4. The drain of the PMOS transistor U2 is respectively connected to one end of a capacitor C2, one end of a resistor R5, the collector of the NPN transistor Q2, one end of a capacitor C3, and the source of the PMOS transistor U3. The other end of the capacitor C2 is grounded. The other end of the resistor R5 is respectively connected to one end of the resistor R8, the base of the PNP transistor Q3, and the base of the NPN transistor Q2. The emitter of the NPN transistor Q2 is connected to one end of the resistor R6. The other end of the resistor R6 is respectively connected to one end of the resistor R7, the other end of the capacitor C3, and the gate of the PMOS transistor U3. The other end of the resistor R7 is connected to the emitter of the PNP transistor Q3. The collector of the PNP transistor Q3 is grounded. The drain of the PMOS transistor U3 is connected to the humidifier heating state acquisition module. The other end of the resistor R8 is respectively connected to the collector of the NPN transistor Q1 and the heating switching module.

[0014] According to a heating control circuit provided by the present utility model, the breathing tube heating state processing module includes a breathing tube heating detection unit, a breathing tube temperature control unit, and a second driving unit. The input end of the breathing tube heating state detection unit is connected to the breathing tube heating state acquisition module for detecting the heating state of the breathing tube. The output end of the breathing tube heating detection unit is respectively connected to the breathing tube heating power adjustment module and the heating switching module. The breathing tube heating power adjustment module is connected to the second driving unit. The second driving unit is respectively connected to the breathing tube temperature control unit and the breathing tube heating state acquisition module.

[0015] According to a heating control circuit provided by the present utility model, the breathing tube heating detection unit includes a pre-amplification unit and a comparison unit. The heating resistance value collected by the breathing tube heating state acquisition module is connected to the input end of the pre-amplification unit. The comparison unit is respectively connected to the output end of the pre-amplification unit and a first threshold voltage for detecting the heating state of the breathing tube. If the voltage amplified by the pre-amplification unit is higher than the first threshold voltage, the second voltage is at a high level; if the voltage at the output end of the pre-amplification unit is lower than the first threshold voltage, the second voltage is at a low level.

[0016] According to a heating control circuit provided by the present utility model, the breathing tube heating adjustment module includes a resistor R9, a resistor R10, a resistor R11, a capacitor C4, a diode D3, and an NPN transistor Q4. One end of the resistor R9 is connected to a PWM signal, the other end of the resistor R9 is connected to one end of the capacitor C4, and the other end of the capacitor C4 is respectively connected to one end of the resistor R10, the cathode of the diode D3, the base of the NPN transistor Q4, and the output end of the breathing tube heating detection unit. The other end of the resistor R10 is grounded, the anode of the diode D3 is grounded, and the collector of the NPN transistor Q4 is connected to the second driving unit.

[0017] According to a ventilator provided by the present utility model, the ventilator includes a main unit, a breathing mask, a breathing tube, a humidifier, a humidifier heating plate, and the heating control circuit as described above. The breathing tube is connected between the main unit and the breathing mask. The main unit is provided with a heating plate for heating the humidifier. The humidifier is movably connected to the main unit, and the heating control circuit is arranged inside the ventilator.

[0018] According to a ventilator provided by the present utility model, the main unit is provided with a power supply, and the heating control circuit of the ventilator is electrically connected to the power supply.

[0019] The heating control circuit provided by the present utility model controls the heating mode of the ventilator by using a heating switching module. According to the comparison of the first voltage between the humidifier heating power adjustment module and the humidifier heating state processing module and the second voltage between the breathing tube heating state processing module and the breathing tube heating power adjustment module, the heating mode of the ventilator is switched. If the first voltage is higher than the second voltage, the heating mode of the ventilator is humidifier heating. If the first voltage is lower than the second voltage, the heating mode of the ventilator is breathing tube heating. The heating control circuit avoids the risk of excessive surface temperature of the circuit caused by heating the humidifier and the ventilator simultaneously using a high-power power supply, improves the reliability of the ventilator. At the same time, the heating control circuit monitors the heating temperature of the humidifier and the breathing tube, and implements the principle of power-off in case of overheating, further avoiding the safety risk caused by excessive temperature during the use of the ventilator. Description of the Drawings

[0020] In order to more clearly illustrate the technical solutions in the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0021] Figure 1 is the principle block diagram of the heating control circuit provided by the present utility model;

[0022] Figure 2 is the principle block diagram of the humidifier heating state processing module provided by the present utility model;

[0023] Figure 3 is the schematic diagram of the humidifier heating power adjustment module provided by the present utility model;

[0024] Figure 4 is the principle block diagram of the breathing tube heating state processing module provided by the present utility model;

[0025] Figure 5 is the schematic diagram of the first driving unit provided by the present utility model;

[0026] Figure 6 is the schematic diagram of the breathing tube heating power adjustment module provided by this embodiment;

[0027] Figure 7 is the structural schematic diagram of a ventilator provided by this embodiment; Detailed implementation manners

[0028] The present utility model will be further described in detail below in conjunction with the accompanying drawings through specific implementation manners. Similar elements in different embodiments are labeled with related similar element numbers. In the following embodiments, many detailed descriptions are provided to enable a better understanding of the present application. However, those skilled in the art can easily recognize that some of the features can be omitted in different situations, or can be replaced by other elements, materials, or methods. In some cases, some operations related to the present application are not shown or described in the specification, which is to avoid the core part of the present application being overwhelmed by excessive descriptions. For those skilled in the art, it is not necessary to describe these related operations in detail, and they can fully understand the related operations based on the descriptions in the specification and the general technical knowledge in the art.

[0029] In addition, the features, operations, or characteristics described in the specification can be combined in any appropriate manner to form various embodiments. The various sequences in the specification and the drawings are only for clearly describing a certain embodiment and do not mean that they are the necessary sequences, unless it is stated that a certain sequence must be followed.

[0030] The serial numbers assigned to the components in this article, such as "first", "second", etc., are only used to distinguish the described objects and do not have any sequential or technical meanings. The "connection" and "coupling" mentioned in this application, unless otherwise specified, both include direct and indirect connections (couplings).

[0031] In one embodiment, a heating control circuit is provided, which mainly controls the heating states of the ventilator humidifier and the breathing tube. As Figure 1 shown, the heating control circuit 100 includes:

[0032] A humidifier heating state processing module 110, a humidifier heating state acquisition module 120, a humidifier heating power adjustment module 130, a heating switching module 140, a breathing tube heating state processing module 150, a breathing tube heating power adjustment module 160, and a breathing tube heating state acquisition module 170, where:

[0033] The humidifier heating power adjustment module 130 is connected to the humidifier heating state processing module 110, and the humidifier heating state processing module 110 is connected to the humidifier heating state acquisition module 120;

[0034] The breathing tube heating power adjustment module 160 is connected to the breathing tube heating state processing module 150, and the breathing tube heating state processing module 150 is connected to the breathing tube heating state acquisition module 170;

[0035] The heating switching module 140 is connected to the humidifier heating power adjustment module 130, the humidifier heating state processing module 110, the breathing tube heating state processing module 150, and the breathing tube heating power adjustment module 160, and is used to switch the ventilator heating mode according to the voltage comparison between the first voltage between the humidifier heating power adjustment module 130 and the humidifier heating state processing module 110 and the second voltage between the breathing tube heating state processing module 150 and the breathing tube heating power adjustment module 160. If the first voltage is higher than the second voltage, the ventilator heating mode is humidifier heating; if the first voltage is lower than the second voltage, the ventilator heating mode is breathing tube heating.

[0036] In this embodiment, the humidifier heating state acquisition module 120 acquires the heating resistance value of the thermistor of the heating plate for heating the ventilator humidifier; the breathing tube heating state acquisition module 170 acquires the heating resistance value of the corresponding thermistor when the breathing tube is heated by the heating resistance wire.

[0037] In one embodiment, the heating switching module 140 includes a diode D1, the first voltage is connected to the cathode of the diode D1, and the second voltage is connected to the anode of the diode D1.

[0038] In this embodiment, if the first voltage is higher than the second voltage, the diode D1 is in the cut-off state, and the heating mode of the ventilator is the humidifier heating mode. If the first voltage is lower than the second voltage, the diode D1 is in the conducting state, and the heating mode of the ventilator is the breathing tube heating. By switching the heating mode of the ventilator through the conduction and cut-off of the diode D1, the simultaneous heating of the humidifier and the breathing tube is avoided, thereby avoiding the safety risk of excessive surface temperature of the circuit due to the large output power of the heating power supply. Moreover, the structure is simple and the production cost is low.

[0039] In one embodiment, as Figure 2 shown, the humidifier heating state processing module 110 includes a humidifier heating state detection unit 111, a heating temperature control unit 112, and a first driving unit 113. The heating resistance value collected by the humidifier heating state acquisition module 120 is connected to the humidifier heating state detection unit 111 for detecting the heating state of the humidifier. The input end of the heating temperature control unit 112 is connected to the output end of the humidifier heating state detection unit 111 for limiting the heating temperature of the humidifier. The input end of the first driving unit 113 is connected to the output end of the heating temperature control unit 112 for driving the humidifier to heat.

[0040] In this embodiment, the heating state of the humidifier includes two states: heating and non-heating. When the humidifier heating state detection unit 111 detects that the humidifier is in the heating state, the heating temperature control unit 112 limits the heating temperature of the humidifier. Specifically, the heating temperature control unit 112 compares the heating voltage of the humidifier heating plate collected by the humidifier heating state acquisition module 120 with the over-temperature threshold voltage of the humidifier. If the detected heating voltage is greater than the over-temperature threshold voltage, the temperature of the humidifier heating plate is in the over-temperature state at this time, and the heating temperature control unit 112 controls the first driving unit 113 to stop heating the humidifier heating plate; if the detected heating voltage is less than the over-temperature threshold voltage, the temperature of the humidifier heating plate is in the normal temperature range at this time, and the heating temperature control unit 112 controls the first driving unit 113 to heat the humidifier heating plate. When the humidifier heating state detection unit 111 detects that the humidifier is in the non-heating state, the heating temperature control unit 112 stops limiting the heating temperature of the humidifier.

[0041] In this embodiment, the heating voltage of the humidifier heating plate corresponds one-to-one to the heating temperature of the humidifier heating plate.

[0042] In this embodiment, the heating temperature of the humidifier heating plate is limited by the heating temperature control unit 112, preventing the temperature of the humidifier heating plate from being too high, avoiding the safety risk caused by the too high temperature of the humidifier heating plate, and improving the heating reliability of the ventilator.

[0043] In one embodiment, as Figure 3 shown, the humidifier heating power adjustment module includes a resistor R1, a capacitor C1, a resistor R2, a diode D2, and an NPN transistor Q1. One end of the resistor R1 is connected to a PWM signal, and the other end is connected to one end of the capacitor C1. The other end of the capacitor C1 is respectively connected to the base of the NPN transistor Q1, one end of the resistor R2, and the cathode of the diode D2. The other end of the resistor R2 is grounded, the anode of the diode D2 is grounded, the emitter of the NPN transistor Q1 is grounded, and the collector of the NPN transistor Q1 is respectively connected to the humidifier heating state processing module and the heating switching module.

[0044] In this embodiment, the resistor R1, the capacitor C1, and the resistor R2 form a low-pass filter to filter the high-order odd harmonics of the PWM signal, and the diode D2 is used to prevent the NPN transistor Q1 from being broken down.

[0045] In this embodiment, the humidifier heating power adjustment module 130 controls the conduction and cut-off of the NPN transistor Q1 by using the PWM signal, further controls the humidifier heating power supply to supply power to the energy storage capacitor in the humidifier heating state acquisition module 120 at a certain frequency, and heats the humidifier heating plate at the same time. Furthermore, the heating power of the humidifier heating plate is adjusted by using the charging and discharging of the energy storage capacitor.

[0046] In other embodiments, the first driving unit includes a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a resistor R8, an NPN transistor Q2, a PNP transistor Q3, an NMOS transistor U1, a PMOS transistor U2, a PMOS transistor U3, and a humidifier heating power supply. Among them, the output end of the heating temperature control unit is connected to the gate of the NMOS transistor U1. The source of the NMOS transistor U1 is grounded. The drain of the NMOS transistor U1 is connected to one end of the resistor R3, and the other end of the resistor R3 is connected to one end of the resistor R4. The other end of the resistor R4 is respectively connected to the source of the PMOS transistor U2 and the humidifier heating power supply. The gate of the PMOS transistor U2 is connected to one end of the resistor R4. The drain of the PMOS transistor U2 is respectively connected to one end of a capacitor C2, one end of a resistor R5, the collector of the NPN transistor Q2, one end of a capacitor C3, and the source of the PMOS transistor U3. The other end of the capacitor C2 is grounded. The other end of the resistor R5 is respectively connected to one end of a resistor R8, the base of the PNP transistor Q3, and the base of the NPN transistor Q2. The emitter of the NPN transistor Q2 is connected to one end of the resistor R6. The other end of the resistor R6 is respectively connected to one end of the resistor R7, the other end of the capacitor C3, and the gate of the PMOS transistor U3. The other end of the resistor R7 is connected to the emitter of the PNP transistor Q3. The collector of the PNP transistor Q3 is grounded. The drain of the PMOS transistor U3 is connected to the humidifier heating state acquisition module. The other end of the resistor R8 is respectively connected to the collector of the NPN transistor Q1 and the heating switching module.

[0047] In this embodiment, when the heating method of the ventilator is humidifier heating, the humidifier heating state detection unit 111 detects that the humidifier is in the heating state. At the same time, when the heating temperature control unit 112 detects that the temperature of the humidifier heating plate is within the normal range, the NMOS transistor U1 is turned on at this time, that is, the gate voltage of the NMOS transistor U1 is greater than the source voltage. At this time, one end of the resistor R3 is grounded, and the gate voltage of the PMOS transistor U2 is the voltage after the humidifier heating power supply is divided by the resistors R3 and R4. The gate voltage of the PMOS transistor U2 is less than the source voltage, and the PMOS transistor U2 is turned on. The drain voltage of the PMOS transistor U2 is the humidifier heating power supply voltage. Since the heating method of the ventilator is humidifier heating, the heating switching method is switched to humidifier heating at this time, that is, the first voltage is higher than the second voltage. At this time, when the PWM signal output is high, the NPN transistor Q1 is turned on. At this time, the resistor R8 is equivalent to being grounded, and the base voltages of the NPN transistor Q2 and the PNP transistor Q3 are equivalent to the divided voltage between the resistors R5 and R8 for the power supply voltage. At this time, the NPN transistor Q2 is turned on, and the PNP transistor Q3 is turned off. The gate voltage of the PMOS transistor U3 is the voltage obtained by dividing the humidifier heating power supply by the resistors R7 and R8 for the resistors R6, R7, and R8. The source voltage of the PMOS transistor U3 is the humidifier heating power supply voltage. The gate voltage of the PMOS transistor U3 is less than the source voltage, and the PMOS transistor U3 is turned on. The drain voltage of the PMOS transistor U3 is the humidifier heating power supply voltage, providing heating power for the humidifier heating state acquisition module; when the PWM signal output is low, the NPN transistor Q1 is turned off. At this time, the base voltages of the NPN transistor Q2 and the PNP transistor Q3 are equivalent to the humidifier power supply voltage and are not turned on. At this time, the gate voltage of the PMOS transistor U3 is greater than the source voltage, and the PMOS transistor U3 is turned off, unable to provide heating power for the humidifier heating state acquisition module, and the humidifier heating plate stops heating.

[0048] In this embodiment, when the PWM signal outputs a high level, the first voltage is zero, and when the PWM signal outputs a low level, the first voltage is the humidifier heating power supply voltage.

[0049] In one embodiment, such as Figure 4As shown, the breathing tube heating state processing module 150 includes a breathing tube heating detection unit 151, a breathing tube temperature control unit 152, and a second driving unit 153. The input end of the breathing tube heating state detection unit 151 is connected to the breathing tube heating state acquisition module 170 for detecting the heating state of the breathing tube. The output end of the breathing tube heating detection unit 151 is respectively connected to the breathing tube heating power adjustment module 160 and the heating switching module 140. The breathing tube heating power adjustment module 160 is connected to the second driving unit 153, and the second driving unit 153 is respectively connected to the breathing tube temperature control unit 152 and the breathing tube heating state acquisition module 170.

[0050] In this embodiment, the heating state of the breathing tube includes two states: heating and non - heating. When the breathing tube heating state detection unit 151 detects that the breathing tube is in the heating state, the breathing tube heating state acquisition module 170 is used to compare the detected heating voltage with the breathing tube over - temperature threshold voltage. If the detected heating voltage is greater than the breathing tube over - temperature threshold voltage, then the breathing tube is in the over - temperature state at this time, and the breathing tube heating temperature control unit 152 controls the second driving unit 153 to stop heating the breathing tube; if the detected heating voltage is less than the breathing tube over - temperature threshold voltage, then the breathing tube heating temperature is within the normal temperature range at this time, and the breathing tube heating temperature control unit 152 controls the second driving unit 153 to heat the breathing tube.

[0051] In this embodiment, the design of the second driving unit 153 is the same as that of the first driving unit 113, and will not be elaborated here.

[0052] In other embodiments, the breathing tube heating detection unit 151 includes a pre - amplifier unit and a comparison unit. The heating resistance value collected by the breathing tube heating state acquisition module 170 is connected to the input end of the pre - amplifier unit. The comparison unit is respectively connected to the output end of the pre - amplifier unit and the first threshold voltage for detecting the heating state of the breathing tube. If the voltage amplified by the pre - amplifier unit is higher than the first threshold voltage, the second voltage is at a high level; if the voltage at the output end of the pre - amplifier unit is lower than the first threshold voltage, the second voltage is at a low level.

[0053] In this embodiment, the breathing pipeline heating state acquisition module 170 acquires the heating resistance value of the thermistor corresponding to the heating of the breathing pipeline by using a heating resistance wire. The heating resistance value is converted into a voltage change and amplified by the pre-amplification unit. The voltage representing the heating resistance value signal after amplification is compared with the first threshold voltage. When the voltage representing the heating resistance value signal after amplification is higher than the first threshold voltage, the second voltage is at a high level at this time, that is, the breathing pipeline is in a heating state. When the voltage representing the heating resistance value signal after amplification is lower than the first threshold voltage, the second voltage is at a low level at this time, that is, the breathing pipeline is in a non-heating state.

[0054] In other embodiments, as Figure 5 shown, the breathing pipeline heating adjustment module 130 includes a resistor R9, a resistor R10, a resistor R11, a capacitor C4, a diode D3, and an NPN transistor Q4. Specifically, the PWM signal is connected to one end of the resistor R9, the other end of the resistor R9 is connected to one end of the capacitor C4, and the other end of the capacitor C4 is respectively connected to one end of the resistor R10, the cathode of the diode D3, the base of the NPN transistor Q4, and the output end of the breathing pipeline heating detection unit 151. The second end of the resistor R10 is grounded, the other end of the diode D3 is grounded at the anode, and the collector of the NPN transistor Q4 is connected to the breathing pipeline temperature control module and the second driving module.

[0055] In this embodiment, the resistor R9, the capacitor C4, and the resistor R10 form a low-pass filter to filter the high-order odd harmonics of the PWM signal, and the diode D3 is used to prevent the NPN transistor Q4 from being broken down.

[0056] In this embodiment, when the heating switching module 140 is the diode D1 and the PWM signal in the humidifier heating power adjustment module 130 is at a high level, the NPN transistor Q1 conducts, and the first voltage is 0. When the breathing tube heating state detection unit 151 detects that the breathing tube is in the heating state, the output end of the breathing tube heating detection unit 151 is at a high level. At this time, the second voltage is greater than the first voltage, and the diode D1 conducts. The second voltage changes from a high level to 0. At this time, the base voltage of the NPN transistor Q4 connected to the output end of the breathing tube heating detection unit 151 is 0, and the NPN transistor Q4 cuts off. The second driving unit stops providing heating power to the breathing tube, that is, the breathing tube stops heating. When the PWM signal is at a low level, the NPN transistor Q1 cuts off. At this time, the diode D1 cuts off, and the first driving unit 113 stops providing heating power to the humidifier heating plate, that is, the humidifier heating plate stops heating. At the same time, when the breathing tube heating state detection unit 151 detects that the breathing tube is in the heating state, the output end of the breathing tube heating detection unit 151 is at a high level. At this time, the base of the NPN transistor Q4 is at a high level, the base of the NPN transistor Q4 conducts, and the second driving unit provides heating power to the breathing tube, that is, the breathing tube heats up.

[0057] In this embodiment, by the cooperation of the heating switching module 140 and the NPN transistor Q1, when the humidifier is heated, the safety risk of excessive surface temperature of the circuit due to simultaneous heating of the breathing tube is avoided. At the same time, the PWM signal makes the NPN transistor Q1 conduct at a certain frequency, so that the heating of the breathing tube and the humidifier can be switched at a certain frequency, avoiding the occurrence of condensate in the breathing tube due to long-term heating of the humidifier by the ventilator, which may cause the patient to cough.

[0058] As Figure 7 shown, it is a schematic structural diagram of a ventilator provided by an embodiment of the present application. The ventilator includes a host 1, a breathing mask 2, a breathing tube 3, a humidifier 4, a humidifier heating plate 5, and a heating control circuit 100. The breathing tube 3 is connected between the host 1 and the breathing mask 2. The host 1 is fixedly connected to the humidifier heating plate 5 for heating the humidifier 4. The humidifier 4 is movably connected to the host 1. The heating control circuit 100 is arranged inside the ventilator.

[0059] In this embodiment, the host is provided with a power supply 101, and the heating control circuit 100 of the ventilator is electrically connected to the power supply 101. The humidifier heating state acquisition module 120 is arranged on the humidifier heating plate 5, and the breathing tube heating acquisition module 170 is arranged on the breathing tube 3 close to the host 1 side. Since the ventilator adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be elaborated here one by one.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A heating control circuit, characterized in that: include: Humidifier heating state processing module, humidifier heating state acquisition module, humidifier heating power adjustment module, heating switching module, breathing circuit heating state processing module, breathing circuit heating power adjustment module, breathing circuit heating state acquisition module, wherein: The humidifier heating power adjustment module is connected to the humidifier heating state processing module, and the humidifier heating state processing module is connected to the humidifier heating state acquisition module; The breathing circuit heating power adjustment module is connected to the breathing circuit heating state processing module, and the breathing circuit heating state processing module is connected to the breathing circuit heating state acquisition module; The heating switching module is connected to the humidifier heating power adjustment module, the humidifier heating state processing module, the breathing circuit heating state processing module, and the breathing circuit heating power adjustment module, and is used to switch the ventilator heating mode according to a voltage comparison of a first voltage between the humidifier heating power adjustment module and the humidifier heating state processing module and a second voltage between the breathing circuit heating state processing module and the breathing circuit heating power adjustment module. If the first voltage is higher than the second voltage, the ventilator heating mode is humidifier heating; if the first voltage is lower than the second voltage, the ventilator heating mode is breathing circuit heating.

2. The heating control circuit according to claim 1, characterized in that: The heating switching module includes a diode D1 , the first voltage is connected to a cathode of the diode D1 , and the second voltage is connected to an anode of the diode D1 .

3. The heating control circuit according to claim 1, characterized in that: The humidifier heating state processing module includes a humidifier heating state detection unit, a heating temperature control unit, and a first driving unit. The heating resistance value collected by the humidifier heating state acquisition module is connected to the input end of the humidifier heating state detection unit for detecting the heating state of the humidifier. The input end of the heating temperature control unit is connected to the output end of the humidifier heating state detection unit for limiting the heating temperature of the humidifier. The input end of the first driving unit is connected to the output end of the heating temperature control unit for driving the humidifier to heat.

4. The heating control circuit according to claim 3, characterized in that: The humidifier heating power adjustment module includes a resistor R1, a capacitor C1, a resistor R2, a diode D2, and an NPN transistor Q1, wherein one end of the resistor R1 is connected to the PWM signal, and the other end is connected to one end of the capacitor C1, the other end of the capacitor C1 is respectively connected to the base of the NPN transistor Q1, one end of the resistor R2, and the cathode of the diode D2, the other end of the resistor R2 is grounded, the anode of the diode D2 is grounded, the emitter of the NPN transistor Q1 is grounded, and the collector of the NPN transistor Q1 is respectively connected to the humidifier heating state processing module and the heating switching module.

5. The heating control circuit according to claim 4, characterized in that: The first driving unit includes a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a resistor R8, an NPN transistor Q2, a PNP transistor Q3, an NMOS tube U1, a PMOS tube U2, a PMOS tube U3, and a humidifier heating power supply, wherein the output end of the heating temperature control unit is connected to the gate of the NMOS tube U1, the source of the NMOS tube U1 is grounded, the drain of the NMOS tube U1 is connected to one end of the resistor R3, the other end of the resistor R3 is connected to one end of the resistor R4, the other end of the resistor R4 is respectively connected to the source of the PMOS tube U2 and the humidifier heating power supply, the gate of the PMOS tube U2 is connected to one end of the resistor R4, the drain of the PMOS tube U2 is respectively connected to one end of the capacitor C2, and the drain of the PMOS tube U2 is respectively connected to one end of the capacitor C2. , one end of the resistor R5, the collector of the NPN transistor Q2, one end of the capacitor C3, and the source of the PMOS tube U3 are connected, the other end of the capacitor C2 is grounded, the other end of the resistor R5 is respectively connected to one end of the resistor R8, the base of the PNP transistor Q3, and the base of the NPN transistor Q2, the emitter of the NPN transistor Q2 is connected to one end of the resistor R6, the other end of the resistor R6 is respectively connected to one end of the resistor R7, the other end of the capacitor C3, and the gate of the PMOS tube U3, the other end of the resistor R7 is connected to the emitter of the PNP transistor Q3, the collector of the PNP transistor Q3 is grounded, the drain of the PMOS tube U3 is connected to the humidifier heating state acquisition module, and the other end of the resistor R8 is respectively connected to the collector of the NPN transistor Q1 and the heating switching module.

6. The heating control circuit according to claim 1, characterized in that: The breathing circuit heating state processing module includes a breathing circuit heating detection unit, a breathing circuit temperature control unit, and a second driving unit. The input end of the breathing circuit heating state detection unit is connected to the breathing circuit heating state acquisition module for detecting the heating state of the breathing circuit. The output end of the breathing circuit heating detection unit is respectively connected to the breathing circuit heating power adjustment module and the heating switching module. The breathing circuit heating power adjustment module is connected to the second driving unit. The second driving unit is respectively connected to the breathing circuit temperature control unit and the breathing circuit heating state acquisition module.

7. The heating control circuit according to claim 6, characterized in that: The breathing circuit heating detection unit includes a pre-stage amplifier unit and a comparison unit. The heating resistance value collected by the breathing circuit heating status collection module is connected to the input end of the pre-stage amplifier unit. The comparison unit is respectively connected to the output end of the pre-stage amplifier unit and a first threshold voltage, and is used to detect the heating state of the breathing circuit. If the voltage amplified by the pre-stage amplifier unit is higher than the first threshold voltage, the second voltage is a high level; if the output end voltage of the pre-stage amplifier unit is lower than the first threshold voltage, the second voltage is a low level.

8. The heating control circuit according to claim 7, characterized in that: The breathing circuit heating adjustment module includes a resistor R9, a resistor R10, a resistor R11, a capacitor C4, a diode D3, and an NPN transistor Q4, wherein one end of the resistor R9 is connected to the PWM signal, the other end of the resistor R9 is connected to one end of the capacitor C4, the other end of the capacitor C4 is respectively connected to one end of the resistor R10, the cathode of the diode D3, the base of the NPN transistor Q4, and the output end of the breathing circuit heating detection unit, the other end of the resistor R10 is grounded, the anode of the diode D3 is grounded, and the collector of the NPN transistor Q4 is connected to the second driving unit.

9. A ventilator, characterized in that: The ventilator includes a host, a breathing mask, a breathing circuit, a humidifier, a humidifier heating plate and a heating control circuit as described in any one of claims 1 to 8, the breathing circuit is connected between the host and the breathing mask, the host is provided with a heating plate for heating the humidifier, the humidifier is movably connected to the host, and the heating control circuit is arranged inside the ventilator.

10. The ventilator according to claim 9, characterized in that: The host is provided with a power supply, and the heating control circuit of the ventilator is electrically connected to the power supply.

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