Ventilator system including improved valve

Abstract

A respiratory artificial respirator system comprises: an inlet configured to be connected to a pressurized air or gas source; an outlet configured to be connected to a patient interface; a valve connected by a line between the inlet and the outlet; and a control unit configured to control the valve to control the flow of pressurized air or gas from the source to the patient, wherein the valve may include an air or gas reservoir or accumulator integrated into the valve body.

Description

Technology Field

[0001] The present invention generally relates to a respiratory management system, and more specifically to a mechanical respiratory system or a respiratory management system, namely an artificial respirator or respirator. The present invention is particularly useful for providing respiratory assistance to patients, whether human or animal, whose respiration is impaired due to disease, and, as will be described in relation to this usefulness, it may also be utilized to treat patients suffering from sleep apnea or as a component of an anesthesia system. Background Technology

[0002] The current COVID-19 pandemic has highlighted the need for mechanical ventilator systems for patients with impaired respiratory systems. Respiratory therapy devices function to supply clean, breathable gases (normal air, with or without additional oxygen) to the patient at appropriate times during the patient's respiratory cycle, either at a pressure or at a therapeutic pressure. Therapeutic pressure assist can be implemented in a manner synchronized with the patient's breathing to allow for higher pressure during the inspiratory cycle of normal respiration and lower pressure during expiratory respiration. Therapeutic pressure assist may also be implemented to bypass the patient's normal inspiratory cycle.

[0003] A respiratory management system generally includes a gas or air flow generator or a compressed gas or air source, an air filter, a nasal, oral, or full-face mask, an air delivery duct connecting the flow generator and the mask, various sensors, and a microprocessor-based controller. Optionally, a tracheotomy tube may be used as a patient interface instead of a mask. The flow generator may include a servo-controlled motor and an impeller forming the blower. In some cases, a brake for the blower motor may be implemented to reduce the blower speed more rapidly to overcome the inertia of the motor and impeller. Through braking, the blower can achieve a lower pressure state more quickly, synchronized with the patient's exhalation, despite inertia. In some cases, the flow generator may also include a valve configured to release the generated air into the atmosphere as a means to change the pressure delivered to the patient, as an alternative to motor speed control. Sensors measure motor speed, mass flow rate, and outlet pressure, particularly using pressure transducers. The device may optionally include humidifier and / or heater elements in the path of the air delivery circuit. The controller may include data storage capacity with or without integrated data search and display functions.

[0004] Respiratory management systems can be used to treat various conditions, such as respiratory failure or impairment due to lung, neuromuscular, or musculoskeletal diseases, and respiratory control disorders. They can also be used for sleep disordered breathing (SDB) (including obstructive sleep apnea (OSA)), upper airway obstruction due to allergies, or conditions associated with initial viral infections of the upper airway.

[0005] The supply of respiratory treatment systems has expanded due to the current COVID-19 pandemic. Hospitals have been forced to share respiratory management systems, such as ventilators, between two patients. Hospitals have also adopted devices used for obstructive sleep apnea as inadequate substitutes for conventional ventilators.

[0006] In addition, current ventilators are expensive devices that require complex and continuous supervision and adjustment and are prone to failure. Prior art includes WO 2017 / 029629, disclosed on February 23, 2017.

[0007] The present invention provides a simple and low-cost ventilator that overcomes the aforementioned disadvantages and other disadvantages of ventilators at the current level of technology.

[0008] More specifically, the present invention provides a ventilator that offers significant advantages over current ventilators in terms of cost, size reduction, weight reduction, power reduction, noise reduction, and reliability. One key feature of the ventilator of the present invention is a unique air or gas flow valve equipped with an air or gas reservoir or accumulator integrated into the valve. Integrating the air / gas reservoir or accumulator into the valve simplifies system configuration and costs while providing improved response times, thereby enabling better patient support. Conventional ventilators utilize proportional solenoid valves (PSOLs) or turbine-based designs, where the core flow / pressure regulating component is an expensive, multi-part item (order price $1,500–$2,000). Furthermore, in practice, static friction at the plunger guide post of a conventional PSOL valve can impair valve sensitivity and lead to hysteresis effects. To overcome the above disadvantages and other disadvantages of conventional ventilators, the present invention uses a new low-cost air or gas valve in which an integrated air or gas reservoir or accumulator is integrated into the valve and the valve is essentially composed of five main elements and one moving part.

[0009] In one embodiment, the respiratory ventilator system of the present disclosure comprises: an inlet configured to be connected to a pressurized air or gas source; an outlet configured to be connected to a patient interface; a valve connected in a line between the inlet and the outlet; and a control unit configured to control the valve to control the flow of pressurized air or gas from the source to the patient, wherein the valve comprises an air or gas reservoir or accumulator integrated into the valve body.

[0010] In a preferred embodiment, the valve includes a valve gate controlled by a linear drive mechanism, preferably a servo mechanism, a mechanical screw drive, or a voice coil drive.

[0011] The patient interface may be selected from a group including a mask, an intubation tube, and a tracheostomy cannula, and the pressurized air or gas source may be selected from a group consisting of an air canister, a compressor, an air pump, and a pressurized airline.

[0012] The present invention also provides a method for assisting the breathing of a patient who requires breathing, the method comprising the steps of: providing a ventilator system as described above; connecting the ventilator system to a pressurized air source and a patient interface; and initiating the flow of air or gas into the ventilator system to pre-charge an air or gas reservoir or accumulator, and controlling the flow of gas through the ventilator system by opening and closing a valve.

[0013] In another embodiment of the present invention, the ventilator system includes a heater and / or humidifier for regulating air or gas.

[0014] The valve may open and close according to the patient's normal breathing cycle, or the valve may open and close to introduce a flow of air or gas to override the patient's normal breathing cycle.

[0015] The patient may be a human animal or a non-human animal. Brief explanation of the drawing

[0016] Further features and advantages of the present invention will be apparent from the following description in conjunction with the accompanying drawings, wherein similar reference numerals indicate similar parts. FIG. 1 is a schematic diagram of an artificial respirator system equipped with a small artificial respirator device shown as being connected to a patient according to the present invention. FIG. 2 is a perspective view of a small artificial respiration device manufactured according to the present invention. FIG. 3 is a cross-sectional view illustrating the functional elements of a valve component of a small artificial respiration device according to a preferred embodiment of the present invention. FIGS. 4 and 5 are cross-sectional views illustrating functional elements of valve components of a small artificial respiration device according to the present invention. FIG. 6 is a diagram illustrating the force and moment balance of the valve components of the present invention. FIG. 7 is an exploded view of a valve component according to the present invention. FIG. 8 is a flowchart illustrating the operation of the small artificial respiration device of the present invention. AC in FIG. 9 is a graph illustrating air flow induced according to the present invention. Specific details for implementing the invention

[0017] In the following detailed description, the terms "air" and "gas," and the terms "respirator" and "ventilator" may be used interchangeably.

[0018] The respiratory treatment apparatus of the present invention replenishes air or oxygen to a patient at intermittent time intervals based on the patient's natural tidal cycle or programmed tidal cycle.

[0019] Referring to FIGS. 1 and 2, a ventilator system (10) includes a ventilation controller (12) connected to a pressurized gas source (14). The pressurized gas source may be a pressurized air or air / oxygen gas canister, a compressor or air pump as illustrated, or a pressurized airline. The ventilation controller (12), which will be described in detail below, allows the flow of pressurized gas to the patient through a gas supply line (16) fixed to a patient interface, such as a nasal or face mask (18) worn by the patient (22). Alternatively, the patient interface (18) may include an intubation tube or a tracheotomy cannula. Completing the system are a capnography monitor (24) and a command input monitor (26) that detect and measure inspiratory and / or exhaled airflow from the patient. It should be noted that the capnography monitor (24) and the command input monitor (26) are conventional and do not require further explanation for understanding the invention.

[0020] At the center of the artificial respirator system (10) of the present invention there is a gas or air flow control valve (28) having an integrated gas or air reservoir or accumulator described below.

[0021] Now, referring to FIGS. 3 through 5, the gas or air flow control valve (28) comprises a valve housing (40), which includes the active elements of the gas or air flow control valve (28). A gas supply inlet (42) is shown on the negative X-axis plane, and a gas source outlet (44) is on the positive X-axis plane. Additionally, the housing (40) creates a gas reservoir or accumulator (46). The gas supply inlet (42) may interface with a general hospital O2 source or any gas source (e.g., a gas canister or compressor).

[0022] Referring to FIGS. 3 and 4, the valve gate (48) described below has a source flow rate (Q) based on a position along the X-axis. Source (t), the flow rate is controlled. The surface on the negative Z surface slides along the X-axis of the valve housing slide surface (50). The distance (δ) between the valve gate surface on the positive X-axis of the gate and the valve housing seal surface (52) determines the flow resistance by creating a resistance channel between the valve gate Y-Z surface on the positive X-axis and the valve housing seal surface.

[0023] Referring particularly to FIGS. 5 and 7, the gas or air flow control valve (28) includes a valve gate (48) configured to slide along the X-axis of a valve slide surface (50) that sets a position along the X-axis. The gas or air flow control valve (28) also includes a linear actuator (54), such as a servo mechanism formed of an electrodeformable material like PZT or PMN, a magnetodeformable material, or a mechanical screw drive of a voice coil drive or other linear drive mechanism. The length and the corresponding gate valve position are such that the desired source flow rate Q Source (t) or flow rate source pressure P Source It is controlled under closed loop control based on (t). The valve gate (48) may also be driven under open loop control.

[0024] A preload force in the negative X direction is applied to the valve gate (48) assembly by the spring assembly (56).

[0025] The set screw drives the valve gate (48) in the X direction to set both the spring assembly preload and the initial position of the valve gate (48) along the X-axis.

[0026] The spring plunger (58) provides a preload to the valve gate (48) in the negative Z direction. Its purpose is to continuously maintain a gas-tight seal between the valve gate (48) and the valve housing slide surface (50).

[0027] The gasket (60) maintains a hermetic seal between the XZ surface of the valve housing and the valve gate (48).

[0028] Referring again to FIGS. 1 and 2, the breathing controller (12) includes an air or gas input port (30) connected to a gas or air flow control valve (28). The control valve (28) has an outlet connected to a port including an inspiratory flow connection (34) and an expiratory flow port (36) connected to an expiratory flow valve (38). The expiratory flow valve (38) may be connected to discharge to the atmosphere or to remove CO2 and reuse through the gas input port (30). The system also includes an expiratory flow sensor or breathing sensor (41) for detecting the patient's breathing and connections from the sensor for triggering the valve (28). The sensors may include a patient flow sensor, a temperature sensor, a sound sensor, a CO2 sensor, or a motion or strain sensor for detecting chest movement.

[0029] The valve covers surround the XZ face of the valve housing, one on the positive Y-axis and the other on the negative Y-axis. These covers create a hermetic seal between the valve housing (40) and the atmosphere.

[0030] Referring to FIG. 4-6, on the left side of FIG. 4 is the closed position (δ=0) and valve flow resistance R Valve A valve with (0) infinite is shown. FIG. 4 shows a valve assembly in which the gate is moved a distance δ in the negative direction along the X-axis. As a result, the valve resistance is no longer infinite, and gas flows from the source to the gas storage outlet as shown in the figure.

[0031] Valve flow resistance, R Valve (δ) is calculated as follows.

[0032] Source flow, Q Source (t) is determined by the following mathematical formula 3.

[0033] Storage pressure, P Reservoir (t)

[0034] Outlet pressure, P Outlet (t)

[0035] Source flow rate, Q Source (t)

[0036] Valve height, H Valve

[0037] Valve depth along the Y-axis, D Valve

[0038] Valve gate distance from the valve housing sealing surface, δ

[0039]

[0040] Gas Dynamic Viscosity, η (mass / (distance - time)

[0041]

[0042] The source flow rate can be determined by the following mathematical formula.

[0043]

[0044] The gas source area of ​​the valve housing is required, which is the average source flow rate Q Source (t) is the available supply flow rate Q Supply (t) does not exceed, but Q Source This is because the maximum flow rate of (t) is exceeded.

[0045] This difference is caused by the gas stored in the source.

[0046] The force and moment balance of the generalized valve gate is shown in FIG. 5, and the governing equations for the force balance and moment balance are shown in Equations 4 to 12.

[0047] P Reservoir = Storage pressure

[0048] θ = valve gate angle

[0049] W = Valve gate width

[0050] H = Valve gate height

[0051]

[0052] D Valve = Valve gate depth

[0053] L1, L2 & L3 = Spring distance

[0054] c Friction = Wedge friction coefficient

[0055] Z Actuator = Actuator distance from Z = 0

[0056] P Reservoir = Storage gas pressure

[0057]

[0058]

[0059] F Plunger = Z-direction force of the spring plunger

[0060]

[0061]

[0062] F Spring = Force provided by the preload spring

[0063] F Actuator = Force provided by the positioning actuator

[0064] Z Power Balance

[0065]

[0066]

[0067] X Power Balance

[0068]

[0069] Moment balance about the Y-axis

[0070]

[0071] Also, referring to FIG. 7, the valve assembly (28) has a flow resistance RValve The source gas flow is controlled by changing (δ). This is achieved by changing the length (ΔX, see FIG. 5) of the actuator (54), which ultimately results in moving the valve gate (48) by δ along the X-axis in the corresponding gap between the valve gate (48) and the valve housing sealing surface (52). Storage pressure, P Reservoir (t) is Q as explained by Equation 3 Source To calculate the essential ΔX command controlling (t), it is monitored and utilized by a pressure sensor (70, see FIG. 1).

[0072] The gas flows through a flow sensor at the gas supply inlet (42) and the source flow Q is a function of time t. Source Measure (t). This flow rate measurement is Q as described in Equation 3. Source It is utilized in the gas source controller and sensor / user interface to calculate the ΔX command required to control (t).

[0073] As with conventional ventilators, humidification and / or heating may be required for the inlet gas or flow. This is achieved by a command from the controller to the humidification and heat module (72) (humidifier and heater), which communicates with the reservoir (46), which adds humidity and water vapor to the gas flow through heating and subsequent water evaporation, piezo-atomization of water, or other conventional methods of adding water to the gas flow. The gas may also be heated by this module as it flows.

[0074] The gas flows through a relative humidity sensor that measures the gas relative humidity RH(t) as a function of time t. This measurement is the RH command desired by the controller. Command It is used to generate (t) as a time function.

[0075] The temperature and pressure source module measures the gas temperature T(t). This temperature measurement is used to issue a heating command T to the humidification and heating module to control the gas temperature. Command It is utilized in the controller and sensor / user interface to calculate (t).

[0076] The temperature and pressure source module is the gas outlet pressure P Outlet (t) can also be measured. This pressure is Q as described in Equation 3. Source It is utilized in the controller and sensor / user interface to calculate the ΔX command required to control (t). The outlets of the temperature and pressure modules interface with gas supply lines connected to other patient respiratory devices, such as masks, cannulas, or intubation tubes, or to pressurized nasal ventilators.

[0077] The gas source controller and sensor / user interface are the gas source flow rate Q Source (t), pressure, P Outlet It may include sensor interfaces necessary to control (t), temperature T(t), and relative humidity RH(t). This includes actuator command ΔX(t) and temperature command T Command (t) and relative humidity command RH Command Generates (t). Also, interfaces with a user command input device and a status monitor to control the gas source flow rate, Q Source (t), pressure, P Outlet Receives a user-defined command set for (t), T(t), and RH(t). The gas source controller and sensor / user interface provide sensor readings to the user command input equipment and status monitor.

[0078] Through the user command input equipment and status monitor, the user can control the gas source flow rate, Q Source (t), pressure, P OutletCommands for (t), T(t), and RH(t) can be generated. Sensor readings are also displayed. This equipment may be an iPad-like interface that communicates with a pressurized nasal respirator assembly via wired or wireless means.

[0079] The gas supply line may be a standard O2 line. Additionally, the gas supply line may be insulated to minimize gas heat loss as it travels from the gas source to the pressurized nasal respirator assembly. The gas supply line may also incorporate an electric heating element to maintain the gas temperature and may include a set of power and data wires to provide power to the pressurized nasal respirator assembly and to receive sensor data from the assembly. The gas supply line includes a flow resistance R, which is the pressure at the inlet point of the pressurized nasal respirator gas port. GSL Since we know, P Source (t) is known Q Source (t), P Outlet (t) and R GSL Equation P Source (t) = P Outlet (t) - Q Source (t) R GSL It can be calculated through

[0080] Additional sensors can provide inputs for controlling the gas source assembly. This includes RH sampled through an impedance-based device that monitors respiratory rate and vital capacity via thoracic cavity movement, such as a pressurized nasal ventilator assembly air chamber or system. AC , ETCO2 and / or O2 measurements, air chamber relative humidity, air chamber temperature T AC or air chamber pressure P Chamber It may include (t), but is not limited thereto.

[0081] Referring to FIG. 8, the entire operation is performed as follows: A gas source (14) supplies pressurized gas to a breathing controller (12) that opens a valve (28) to supply gas to the patient (22) at the frequency, flow rate, and pressure required to support the patient's breathing. Because there is a supply of pressurized gas or air to an air or gas reservoir (46) integrated in the valve (28), the delivery of pressurized air or gas to the patient (22) is essentially immediate with the opening of the valve. The air or gas reservoir (46) is refilled while the patient exhales.

[0082] Consequently, the ventilator system of the present invention is a relatively simple device with a lower cost compared to conventional ventilator devices, is robust, convenient, small, and lightweight, and can respond very quickly to the patient's needs.

[0083] AC in Fig. 9 is a flow and pressure waveform showing three rise times (pressure assistance) for the patient.

Claims

Claim 1 A ventilator system comprising: a pressurized air or gas source; and a valve configured to control the flow of pressurized air or gas from the pressurized air or gas source to a patient, wherein the valve comprises: an inlet configured to be connected to the pressurized air or gas source; an outlet configured to be connected to a patient interface; and a control unit configured to control the valve to control the flow of pressurized air or gas from the source to the patient, wherein the valve further comprises a valve gate controlled by a linear drive servo mechanism and an air or gas reservoir integrated within the body of the valve and separated from the pressurized air or gas source to store an amount of pressurized air or gas, wherein when the valve is opened, the air or gas reservoir supplies the amount of pressurized air or gas stored in the air or gas reservoir to the patient along with the pressurized air or gas from the pressurized air or gas source to increase the maximum flow rate of air or gas to the patient, and when the valve is closed, the air or gas reservoir is recharged with the storage of pressurized air or gas. Claim 2 In paragraph 1, the linear drive servo mechanism comprises a mechanical screw drive or a voice coil drive, in an artificial respirator system. Claim 3 In claim 1, the patient interface is a ventilator system selected from the group comprising a mask, an intubation tube, and a tracheostomy cannula. Claim 4 In claim 1, the pressurized air or gas source is a ventilator system selected from the group comprising an air canister, a compressor, an air pump, and a pressurized airline. Claim 5 In paragraph 4, the artificial respirator system further comprises at least one of a heater and a humidifier for regulating air or gas. Claim 6 An artificial respirator system according to claim 1, wherein the air or gas storage tank is in the shape of a conical frustrum integrated within the body of the valve and is configured to store a certain amount of pressurized air or gas, and the conical air or gas storage tank is configured to be filled with the storage of pressurized air or gas when the valve controlling the flow of pressurized air or gas to the patient is closed. Claim 7 delete Claim 8 delete Claim 9 delete Claim 10 delete Claim 11 delete Claim 12 delete

Images