A medical ventilation device

Abstract

A medical ventilation device includes: a turbine assembly connected to a breathing circuit for providing breathable gas to the breathing circuit; a power supply connected to the turbine assembly via a power supply bus for supplying power to the turbine assembly; and a turbine backflow energy discharge circuit disposed on the power supply bus for discharging backflow energy generated by the turbine assembly, comprising: a backflow energy identification circuit for identifying backflow energy; a pulse control circuit for outputting a pulse signal when the vortex backflow energy meets a preset condition, wherein the frequency of the pulse signal is higher than the frequency of the backflow energy; a switching circuit electrically connected to the pulse control circuit for alternately switching on and off under the control of the pulse signal; and a discharge circuit electrically connected to the switching circuit for discharging backflow energy through the switching circuit when the switching circuit is on. This medical ventilation device cuts backflow energy using pulse signals, thereby increasing the absorption power of the discharge circuit.

Description

Technical Field

[0001] This invention relates to the medical field, and more specifically to a medical ventilation device. Background Technology

[0002] Medical ventilation equipment delivers breathable gas to patients via a turbine assembly. When the turbine assembly decelerates or brakes, inertia generates a back electromotive force, causing energy to flow back to the power source; this energy is known as backflow energy. If this backflow energy cannot be released in time, it may lead to excessively high voltage on the power supply bus, damaging the power supply or the turbine drive circuitry.

[0003] In existing technologies, backflow energy is typically discharged using simple resistors or absorbed by large-capacity capacitors, but these methods suffer from problems such as slow response speed, low discharge efficiency, or excessive size. Therefore, there is an urgent need for an efficient, fast, and compact backflow energy discharge solution. Summary of the Invention

[0004] The summary section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. The summary section of this invention is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0005] This invention provides a medical ventilation device, the medical ventilation device comprising:

[0006] A breathing circuit is used to connect to a patient's respiratory system to deliver breathable gas to the patient;

[0007] A turbine assembly, connected to the breathing circuit, is used to supply the breathable gas to the breathing circuit;

[0008] A power supply, connected to the turbine assembly via a power supply bus, is used to supply power to the turbine assembly;

[0009] A turbine backflow energy discharge circuit, disposed on the power supply bus, is used to discharge the backflow energy generated by the turbine assembly. The turbine backflow energy discharge circuit includes:

[0010] Backflow energy identification circuit, used to identify the backflow energy generated by the turbine assembly;

[0011] A pulse control circuit, electrically connected to the backflow energy identification circuit, is used to output a pulse signal when the backflow energy generated by the turbine assembly meets a preset condition, wherein the frequency of the pulse signal is higher than the frequency of the backflow energy generated by the turbine assembly.

[0012] A switching circuit, which is electrically connected to the pulse control circuit, is used to alternately turn the circuit on and off under the control of the pulse signal;

[0013] A discharge circuit, which is electrically connected to the switching circuit, is used to discharge the backflow energy through the switching circuit when the switching circuit is turned on.

[0014] In one embodiment, the turbine backflow energy discharge circuit further includes an anti-backflow circuit, which is disposed between the power source and the turbine assembly to prevent the backflow energy from flowing back to the power source.

[0015] In one embodiment, the backflow energy is the energy that flows back to the power source when the turbine assembly decelerates or stops. When the backflow energy is greater than or equal to a preset threshold, the voltage on the power supply bus is greater than or equal to a first preset voltage, and the backflow energy is discharged through the discharge circuit.

[0016] In one embodiment, the reverse energy identification circuit includes:

[0017] A sampling circuit, at least electrically connected to the power supply bus, is used to collect the voltage on the power supply bus.

[0018] In one embodiment, the sampling circuit includes:

[0019] A positive feedback voltage sampling circuit is used to collect the positive feedback voltage between the anti-backflow circuit and the turbine assembly.

[0020] In one embodiment, the positive feedback voltage sampling circuit includes a first comparison circuit for comparing the positive feedback voltage with a first preset voltage;

[0021] When the positive feedback voltage is greater than the first preset voltage, the positive feedback voltage sampling circuit sends a closed-loop signal to the pulse control circuit to trigger the pulse control circuit to start outputting the pulse signal.

[0022] In one embodiment, the sampling circuit includes:

[0023] A differential mode voltage sampling circuit is electrically connected to both ends of the anti-backflow circuit and is used to collect the differential mode voltage across the anti-backflow circuit.

[0024] In one embodiment, the differential mode voltage sampling circuit includes a second comparison circuit for comparing the differential mode voltage with a second preset voltage, wherein the second preset voltage is less than the first preset voltage;

[0025] When the differential voltage is greater than or equal to the second preset voltage, the differential voltage sampling circuit sends a start signal to the pulse control circuit to start the pulse control circuit.

[0026] In one embodiment, the pulse signal includes a pulse width modulation signal.

[0027] In one embodiment, the pulse control circuit includes a duty cycle limiting circuit for limiting the duty cycle of the pulse signal to not exceed a preset duty cycle.

[0028] In one embodiment, the preset duty cycle is not less than 40%.

[0029] In one embodiment, under the pulse width of the backflow energy generated by the turbine assembly, the ratio of the power absorbed by the discharge circuit to the power of the backflow energy is less than a preset ratio.

[0030] Under the pulse width of the pulse signal, the power ratio of the absorbed power of the discharge circuit to the power of the backflow energy is greater than or equal to one, two, or three times the preset ratio.

[0031] In one embodiment, the bleed circuit includes a plastic-encapsulated surface-mount power resistor.

[0032] In one embodiment, the anti-backflow circuit includes an anti-backflow diode, the anode of which is connected to the power supply, and the cathode of which is connected to the turbine assembly.

[0033] The medical ventilation device of this invention controls the switching circuit to be switched on and off at a high frequency via pulse signals, thereby cutting off backflow energy, increasing the absorption power of the discharge circuit, reducing the requirements on the discharge circuit, and helping the discharge circuit dissipate heat, thus improving the reliability of the medical ventilation device. Attached Figure Description

[0034] The above and other objects, features, and advantages of the present invention will become more apparent from the more detailed description of the embodiments of the invention in conjunction with the accompanying drawings. The drawings are provided to further illustrate the embodiments of the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings, the same reference numerals generally represent the same parts or steps.

[0035] Figure 1 This diagram illustrates the structure of a medical ventilation device according to an embodiment of the present invention.

[0036] Figure 2 A graph showing the relationship between the absorbed power of a plastic-encapsulated power chip resistor and the pulse width according to an embodiment of the present invention is provided. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the present invention more apparent, exemplary embodiments according to the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are merely a part of the embodiments of the present invention, and not all of the embodiments of the present invention. It should be understood that the present invention is not limited to the exemplary embodiments described herein. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention described herein without inventive effort should fall within the protection scope of the present invention.

[0038] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid obscuring the invention.

[0039] It should be understood that the invention can be embodied in various forms and should not be construed as being limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0040] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising” and / or “including,” when used in this specification, identify the presence of said features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0041] For the backflow energy generated by turbo braking, there are three main solutions: absorption by transient voltage suppression diodes (TVS diodes), absorption by energy capacitors, and discharge by power resistors. These three solutions have the following problems:

[0042] 1. The transient power absorption capacity of TVS tubes may not be able to cope with the large energy backflow generated during turbo braking, and high-voltage, high-power TVS tubes are expensive.

[0043] 2. Energy capacitors are large in size, and there is no space to install miniaturized products. In addition, high-capacity energy capacitors are expensive.

[0044] 3. Small-volume plastic-encapsulated surface mount power resistors cannot meet power derating requirements. Only wire-wound, cement, and metal through-hole package resistors can meet power derating requirements. However, these resistors are large and not suitable for miniaturized products.

[0045] To fully understand this invention, a detailed structure will be presented in the following description to illustrate the technical solution proposed by this invention. Optional embodiments of the invention are described in detail below; however, in addition to these detailed descriptions, the invention may have other embodiments.

[0046] Below, we will refer to Figure 1 and Figure 2 A medical ventilation device according to an embodiment of the present invention is described. For example... Figure 1 As shown, the medical ventilation device 100 of this embodiment includes: a breathing circuit 110 for connecting to the patient's respiratory system to deliver breathable gas to the patient; a turbine assembly 120 connected to the breathing circuit 110 for providing breathable gas to the breathing circuit; a power supply 130 connected to the turbine assembly 120 via a power supply bus for supplying power to the turbine assembly 120; and a turbine backflow energy discharge circuit 140 disposed on the power supply bus for discharging the backflow energy generated by the turbine assembly 120.

[0047] The turbine backflow energy discharge circuit 140 includes: a backflow energy identification circuit 141 for identifying the backflow energy generated by the turbine assembly 120; a pulse control circuit 142 electrically connected to the backflow energy identification circuit 141 for outputting a pulse signal when the backflow energy generated by the turbine assembly 120 meets a preset condition, wherein the frequency of the pulse signal is higher than the frequency of the backflow energy generated by the turbine assembly 120; a switch circuit 143 electrically connected to the pulse control circuit 142 for alternately switching on and off under the control of the pulse signal; and a discharge circuit 144 electrically connected to the switch circuit 143 for discharging the backflow energy through the switch circuit 143 when the switch circuit 143 is on.

[0048] Medical ventilation equipment 100 is used to replace, control, or alter a patient's physiological breathing, improving the respiratory function of the ventilated individual and reducing their respiratory expenditure by increasing lung ventilation. Medical ventilation equipment 100 may be a ventilator, anesthesia machine, oxygen therapy machine, etc.

[0049] The medical ventilation device 100 is equipped with a turbine assembly 120, which provides breathable gas to the patient via a breathing circuit 110. The breathing circuit 110 may include an inspiratory branch and an expiratory branch. The inspiratory branch is used to deliver breathable gas to the patient, and the expiratory branch is used to receive the gas exhaled by the patient.

[0050] Exemplarily, the turbine assembly 120 includes a turbine and a turbine drive module. The turbine includes, but is not limited to, a high-speed centrifugal impeller, which converts the mechanical energy provided by the turbine drive module into a continuous, stable airflow for the patient's breathing through rotation. The turbine drive module includes, but is not limited to, a brushless DC motor, which is capable of converting the electrical energy provided by the power supply 130 into controllable mechanical motion of the turbine, ensuring that airflow parameters such as pressure and flow rate meet clinical requirements.

[0051] The turbine assembly 120, as the power source of the medical ventilation device 100, needs to be frequently started and stopped and its power adjusted during ventilation to deliver different flow rates of gas. When the turbine assembly 120 brakes (decelerates or stops), it generates backflow energy, which is essentially the back electromotive force generated by the inertial rotation of the motor. Specifically, during normal operation, the power supply 130 provides electrical energy to the motor, causing it to rotate and drive the turbine to rotate, which then compresses air to deliver the airflow. However, when the turbine assembly 120 brakes or stops suddenly, the power supply 130 stops supplying power, but the turbine continues to rotate due to inertia. The rotating impeller drives the motor rotor to cut magnetic field lines, at which point the motor becomes a generator, generating a back electromotive force. The direction of this back electromotive force is opposite to the polarity of the power supply 130, forming backflow energy that is fed back to the power supply bus.

[0052] To prevent backflow energy from damaging the power supply or other components, this embodiment of the invention includes a turbine backflow energy discharge circuit 140 on the power supply bus to discharge the backflow energy generated by the turbine assembly 120. For example, when the backflow energy is greater than or equal to a preset threshold, the voltage on the power supply bus is greater than or equal to a first preset voltage. This first preset voltage exceeds the withstand voltage of the components connected to the power supply bus, and in this case, the turbine backflow energy discharge circuit 140 is needed to discharge the backflow energy. Conversely, when the backflow energy is less than the preset threshold, the voltage on the power supply bus is less than the first preset voltage. Although backflow energy exists, there is no risk of damage to the components, so there is no need to discharge the backflow energy. Furthermore, this portion of backflow energy can be recycled, reducing energy loss.

[0053] In one embodiment, the turbine backflow energy discharge circuit 140 includes an anti-backflow circuit 145, which is disposed between the power supply 130 and the turbine assembly 120 to prevent backflow energy from flowing back to the power supply 130 and thus avoid damaging the power management chip. Specifically, the first terminal of the anti-backflow circuit 145 is electrically connected to the power supply 120, and the second terminal is electrically connected to the turbine assembly 120. The power supply 130 supplies power to the turbine assembly 120 through the anti-backflow circuit 145. The anti-backflow circuit 145 may include a diode, with its anode connected to the power supply 130 and its cathode electrically connected to the turbine assembly 120. Under normal power supply conditions, when the power supply voltage is greater than the turbine-side voltage, the diode conducts, supplying power to the turbine assembly 120. During energy backflow, when the turbine-side voltage is greater than the power supply voltage, the diode reverse-biased and cuts off, preventing current from flowing back to the power supply 130.

[0054] The turbine backflow energy discharge circuit 140 also includes a backflow energy identification circuit 141 for identifying backflow energy generated by the turbine assembly 120. Exemplarily, the backflow energy identification circuit 141 can identify whether there is backflow energy on the power supply bus and determine whether the backflow energy has reached a preset threshold that needs to be discharged.

[0055] As mentioned above, the essence of backflow energy is the reverse electromotive force generated when the turbine decelerates or stops. The direct manifestation of backflow energy is the voltage rise on the power supply bus. Therefore, the backflow energy identification circuit 141 may include a sampling circuit, which is at least electrically connected to the power supply bus to collect the voltage on the power supply bus. Based on the voltage collected by the sampling circuit, the existence and magnitude of backflow energy can be identified.

[0056] The sampling circuit may specifically include a positive feedback voltage sampling circuit, used to collect the positive feedback voltage between the anti-backflow circuit 145 and the turbine assembly 120. This positive feedback voltage is the total voltage resulting from the superposition of the power supply voltage and the back electromotive force. When the positive feedback voltage exceeds a second preset voltage, the backflow energy is greater than a preset threshold. At this time, the backflow energy needs to be discharged to avoid damaging the components.

[0057] For example, the first terminal of the positive feedback voltage sampling circuit is electrically connected to the second terminal of the anti-backflow circuit 145, and the second terminal of the positive feedback voltage sampling circuit is electrically connected to the input terminal of the pulse control circuit 142. Further, the positive feedback voltage sampling circuit includes a first comparison circuit for comparing the positive feedback voltage with a first preset voltage to determine whether the positive feedback voltage exceeds the first preset voltage. When the positive feedback voltage is greater than the first preset voltage, the positive feedback voltage sampling circuit sends a closed-loop signal to the pulse control circuit 142 to trigger the pulse control circuit 142 to start outputting a pulse signal.

[0058] The first preset voltage is greater than the supply voltage of power supply 130. In one example, power supply 130 uses a BUCK-BOOST converter to boost the voltage (VBUS) on the power supply bus to 28V to supply power to turbine assembly 120. Therefore, the voltage on the power supply bus is 28V when there is no backflow energy. In this example, the first preset voltage can be set to 30V. When the voltage at the output of anti-backflow circuit 145 is detected to be greater than 30V, pulse control circuit 142 starts to output pulse signals to discharge backflow energy.

[0059] Furthermore, the sampling circuit includes a differential mode voltage sampling circuit, which is electrically connected to both ends of the anti-backflow circuit 145 to collect the differential mode voltage across the anti-backflow circuit 145. Specifically, the first end of the differential mode voltage sampling circuit is electrically connected to the first end of the anti-backflow circuit 145, the second end of the differential mode voltage sampling circuit is electrically connected to the second end of the anti-backflow circuit 145, and the third end of the differential mode voltage sampling circuit is electrically connected to the input end of the pulse control circuit 142.

[0060] When the diode constituting the anti-reverse current circuit 145 is forward biased, a small differential-mode voltage exists across its terminals. However, when the diode is reverse biased, the differential-mode voltage across its terminals increases significantly. Therefore, when the differential-mode voltage across the anti-reverse current circuit 145 is greater than a second preset voltage, it can be determined that reverse current energy exists on the power supply bus. For example, the differential-mode voltage sampling circuit may include a second comparison circuit for comparing the detected differential-mode voltage with the second preset voltage to determine whether the differential-mode voltage is greater than the second preset voltage. The second preset voltage is less than the first preset voltage. For example, since the voltage drop of the diode when forward biased is typically below 1V, the second preset voltage is not less than 1V.

[0061] As described above, when the backflow energy on the power supply bus is less than a preset threshold, there is no risk of damage to the components, and there is no need to discharge the backflow energy. Therefore, when the differential mode voltage sampling circuit detects that the differential mode voltage across the anti-backflow circuit 145 is greater than the second preset voltage, the pulse control circuit 142 can be activated, but the switching circuit 143 is temporarily not connected. When the differential mode voltage is greater than or equal to the second preset voltage, the differential mode voltage sampling circuit sends a start signal to the pulse control circuit 142 to activate the pulse control circuit 142. Specifically, the pulse control circuit 142 includes a controller. When no start signal is received, the controller is turned off; when a start signal is received, the controller is turned on, thereby reducing the controller's power consumption.

[0062] The output terminal of the pulse control circuit 142 is connected to the first terminal of the switching circuit 143. The second terminal of the switching circuit 143 is connected to the first terminal of the discharge circuit 144. The second terminal of the discharge circuit 144 is connected to the second terminal of the anti-backflow circuit 145 and the turbine assembly 120. Exemplarily, the third terminal of the switching circuit 143 is grounded. When the switching circuit 143 is turned on, the backflow energy from the turbine assembly 120 is discharged through the discharge circuit 144 and the switching circuit 143. Exemplarily, the switching circuit 143 may include a MOSFET, with the gate of the MOSFET as the first terminal, electrically connected to the pulse control circuit 142; the drain of the MOSFET as the second terminal, electrically connected to the discharge circuit 144; and the source of the MOSFET as the third terminal, used for grounding.

[0063] The switching circuit 143 is alternately turned on and off under the control of the pulse signal. When the switching circuit is on, the discharge circuit 144 discharges the backflow energy through the switching circuit 143. Since the frequency of the pulse signal output by the pulse control circuit 142 is higher than the frequency of the backflow energy generated by the turbine assembly 120, the low-frequency backflow energy can be divided into high-frequency signals. The discharge circuit 144 has a higher absorption power for high-frequency signals, thus reducing the requirements for the discharge circuit 144 and improving the reliability of the equipment.

[0064] For example, the pulse signal output by the pulse control circuit 142 includes a pulse width modulation (PWM) signal, which is a periodic square wave signal composed of a series of high and low levels. For example, a high-level signal controls the switch circuit 143 to turn on, and a low-level signal controls the switch circuit 143 to turn off. The pulse control circuit 142 can adjust the frequency and duty cycle of the PWM signal to control the on-frequency and on-time of the switch circuit 143. In some embodiments, the pulse control circuit 142 can adjust the frequency and duty cycle of the PWM signal according to the magnitude of the backflow energy; for example, the greater the backflow energy, the higher the frequency and the lower the duty cycle, thereby allowing the discharge circuit 144 to absorb more power.

[0065] For example, under the pulse width of the backflow energy generated by the turbine assembly 120, the power ratio of the absorbed power of the discharge circuit 144 to the backflow energy is less than a preset ratio. That is, if the backflow energy is not cut off, the discharge circuit 144 will not be able to effectively discharge the backflow energy. However, under the pulse width of the pulse signal, the power ratio of the absorbed power of the discharge circuit 144 to the backflow energy is greater than or equal to one, two, or three times the preset ratio. In other words, by cutting off the backflow energy based on the pulse signal, the absorbed power of the discharge circuit 144 is effectively increased, thereby reducing the requirements on the discharge circuit 144 and allowing the discharge circuit 144 to use a smaller plastic-encapsulated surface-mount power resistor.

[0066] Specifically, the molded surface mount power resistor is a surface-mount power resistor, small in size and low in cost, suitable for compact spaces. Exemplarily, the molded surface mount power resistor comprises, from top to bottom, a molding layer, leads, bonding points, a resistive layer, and a substrate. The molding layer, made of molding material, protects the internal structure from environmental influences and can be epoxy resin or other high-temperature resistant plastics. The leads provide electrical connections and mechanical fixation, typically made of copper or copper alloys (e.g., tin-plated copper) to improve solderability and corrosion resistance. The bonding points connect the leads to the resistive layer and can use a lead-tin solder structure. The resistive layer provides the resistance value and can be a thick-film resistor, specifically printed on the substrate using nickel-chromium or ruthenium oxide, or a vacuum-deposited thin-film resistor. The substrate supports the resistive layer and dissipates heat, possessing high thermal conductivity and insulation, and can be made of ceramic materials such as alumina or aluminum nitride. Exemplarily, a flange is also provided below the substrate to increase the heat dissipation area and provide mechanical fixation.

[0067] See Figure 2 The graph shows the relationship between the power absorbed by the plastic-encapsulated surface-mount power resistor and the pulse width. When the pulse width of the reverse-flow energy is 3ms and the peak power is 103W, according to the power derating requirement of 0.5, the power resistor's 3ms pulse width pulse power must be greater than 206W. However, referring to... Figure 2 At this point, the power absorbed by the plastic-encapsulated surface mount power resistor cannot meet the power derating requirement.

[0068] In this embodiment of the invention, a high-frequency pulse signal is used to control the switching circuit 143 to divide and discharge the backflow energy. After division, the backflow energy and the pulse signal have the same frequency. When the pulse signal is a PWM signal with a frequency of 80KHz, a duty cycle of 16%, and a pulse width of 2µs, the backflow energy is divided into a high-frequency signal with a pulse width of 2µs. The power absorption of the plastic-encapsulated power resistor for the 2µs pulse width signal is greater than 800W, and the power derating for the 103W backflow energy is 0.128, which is sufficient.

[0069] In some embodiments, the pulse control circuit 142 further includes a duty cycle limiting circuit for limiting the duty cycle of the pulse signal to no more than a preset duty cycle, ensuring that the discharge circuit 144 dissipates heat sufficiently and improving the reliability of the circuit. In one embodiment, the preset threshold is not less than 40%, meaning that during the discharge process, the discharge circuit 144 dissipates heat for at least 40% of the time.

[0070] In summary, the medical ventilation device of this invention controls the switching circuit to be switched on and off at a high frequency via pulse signals, thereby cutting off backflow energy, increasing the absorption power of the discharge circuit, reducing the requirements on the discharge circuit, and helping the discharge circuit dissipate heat, thus improving the reliability of the medical ventilation device.

[0071] Although exemplary embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above exemplary embodiments are merely illustrative and are not intended to limit the scope of the invention. Various changes and modifications can be made therein by those skilled in the art without departing from the scope and spirit of the invention. All such changes and modifications are intended to be included within the scope of the invention as claimed in the appended claims.

[0072] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0073] In the several embodiments provided by this invention, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed.

[0074] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0075] Similarly, it should be understood that, in order to streamline the invention and aid in understanding one or more of the various aspects of the invention, features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof in the description of exemplary embodiments of the invention. However, this approach should not be construed as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as reflected in the corresponding claims, its inventive point lies in solving the corresponding technical problem with fewer features than all of those in a single disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of the invention.

[0076] Those skilled in the art will understand that, apart from the mutual exclusion of features, all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or units of any method or apparatus so disclosed can be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature that serves the same, equivalent, or similar purpose.

[0077] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features but not others included in other embodiments, combinations of features from different embodiments are intended to be within the scope of the invention and form different embodiments. For example, in the claims, any of the claimed embodiments can be used in any combination.

[0078] The various component embodiments of the present invention can be implemented in hardware, or as software modules running on one or more processors, or a combination thereof. Those skilled in the art will understand that microprocessors or digital signal processors (DSPs) can be used in practice to implement some or all of the functions of some modules according to embodiments of the present invention. The present invention can also be implemented as an apparatus program (e.g., a computer program and computer program product) for performing some or all of the methods described herein. Such programs implementing the present invention can be stored on a computer-readable medium, or can be in the form of one or more signals. Such signals can be downloaded from an Internet website, provided on a carrier signal, or provided in any other form.

[0079] It should be noted that the above embodiments are illustrative of the invention and not restrictive, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The invention can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

[0080] The above description is merely a specific embodiment of the present invention or an explanation of that embodiment. The scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. The scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A medical ventilation device, characterized in that, The medical ventilation device includes: A breathing circuit is used to connect to a patient's respiratory system to deliver breathable gas to the patient; A turbine assembly, connected to the breathing circuit, is used to supply the breathable gas to the breathing circuit; A power supply, connected to the turbine assembly via a power supply bus, is used to supply power to the turbine assembly; A turbine backflow energy discharge circuit, disposed on the power supply bus, is used to discharge the backflow energy generated by the turbine assembly. The turbine backflow energy discharge circuit includes: Backflow energy identification circuit, used to identify the backflow energy generated by the turbine assembly; A pulse control circuit, electrically connected to the backflow energy identification circuit, is used to output a pulse signal when the backflow energy generated by the turbine assembly meets a preset condition, wherein the frequency of the pulse signal is higher than the frequency of the backflow energy generated by the turbine assembly. A switching circuit, which is electrically connected to the pulse control circuit, is used to alternately turn the circuit on and off under the control of the pulse signal; A discharge circuit, which is electrically connected to the switching circuit, is used to discharge the backflow energy through the switching circuit when the switching circuit is turned on.

2. The medical ventilation device according to claim 1, characterized in that, The turbine backflow energy discharge circuit also includes an anti-backflow circuit, which is disposed between the power source and the turbine assembly to prevent the backflow energy from flowing back to the power source.

3. The medical ventilation device according to claim 2, characterized in that, The backflow energy is the energy that flows back to the power source when the turbine assembly decelerates or stops. When the backflow energy is greater than or equal to a preset threshold, the voltage on the power supply bus is greater than or equal to a first preset voltage. At this time, the backflow energy is discharged through the discharge circuit.

4. The medical ventilation device according to claim 3, characterized in that, The reverse energy identification circuit includes: A sampling circuit, at least electrically connected to the power supply bus, is used to collect the voltage on the power supply bus.

5. The medical ventilation device according to claim 4, characterized in that, The sampling circuit includes: A positive feedback voltage sampling circuit is used to collect the positive feedback voltage between the anti-backflow circuit and the turbine assembly.

6. The medical ventilation device according to claim 5, characterized in that, The positive feedback voltage sampling circuit includes a first comparison circuit for comparing the positive feedback voltage with the first preset voltage. When the positive feedback voltage is greater than the first preset voltage, the positive feedback voltage sampling circuit sends a closed-loop signal to the pulse control circuit to trigger the pulse control circuit to start outputting the pulse signal.

7. The medical ventilation device according to claim 4, characterized in that, The sampling circuit includes: A differential mode voltage sampling circuit is electrically connected to both ends of the anti-backflow circuit and is used to collect the differential mode voltage across the anti-backflow circuit.

8. The medical ventilation device according to claim 7, characterized in that, The differential mode voltage sampling circuit includes a second comparison circuit for comparing the differential mode voltage with a second preset voltage, wherein the second preset voltage is less than the first preset voltage. When the differential voltage is greater than or equal to the second preset voltage, the differential voltage sampling circuit sends a start signal to the pulse control circuit to start the pulse control circuit.

9. The medical ventilation device according to claim 1, characterized in that, The pulse signal includes a pulse width modulation signal.

10. The medical ventilation device according to claim 1, characterized in that, The pulse control circuit includes a duty cycle limiting circuit, which limits the duty cycle of the pulse signal to no more than a preset duty cycle.

11. The medical ventilation device according to claim 10, characterized in that, The preset duty cycle is not less than 40%.

12. The medical ventilation device according to claim 1, characterized in that, Under the pulse width of the backflow energy generated by the turbine assembly, the ratio of the power absorbed by the discharge circuit to the power of the backflow energy is less than a preset ratio. Under the pulse width of the pulse signal, the power ratio of the absorbed power of the discharge circuit to the power of the backflow energy is greater than or equal to one, two, or three times the preset ratio.

13. The medical ventilation device according to claim 1, characterized in that, The discharge circuit includes a plastic-encapsulated surface-mount power resistor.

14. The medical ventilation device according to claim 2, characterized in that, The backflow prevention circuit includes a backflow prevention diode, the anode of which is connected to the power supply, and the cathode of which is connected to the turbine assembly.

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