CN114288503B - Breathing machine - Google Patents

Abstract

The present invention provides a ventilator comprising: the first air path comprises a first pressure air source interface and a first flow regulating device which are sequentially connected; the second air circuit comprises a second pressure air source interface, a second flow regulating device and a second flow sensor which are sequentially connected; the third air path comprises a third pressure air source interface; a first suction branch; a second suction branch comprising a gas compression device, the outlet of the gas compression device being connected to a second flow regulating means and a second flow sensor; a switching device including a first interface, a second interface, and a third interface, having a first mode of connecting the first interface with the second interface, and a second mode of connecting the first interface with the third interface; and an exhalation branch that manages the patient's exhaled gases. Thus, the mixed gas of the required oxygen concentration can be switched between the first and second modes and supplied in time, and the central gas supply system is not relied upon, and the second flow sensor is shared, so that an increase in cost can be suppressed.

Description

Breathing machine

Technical Field

The invention relates to the field of medical appliances, in particular to a breathing machine.

Background

Ventilators have been widely used in hospitals as medical devices that assist in dyspnea or support in mechanical ventilation of patients who cannot breathe spontaneously. In general, ventilators require two sources of air and oxygen, by mixing the two gases to output a mixture of gases of the desired oxygen concentration to the patient.

Currently, in hospitals provided with a central air supply system capable of providing an air source, the air source of the ventilator is almost all provided by the central air supply system; in hospitals lacking a central air supply system or when the air pressure of the central air supply system is unstable, the existing breathing machine cannot be used for timely rescuing patients.

Disclosure of Invention

The present invention has been made in view of the above circumstances, and an object thereof is to provide a ventilator having at least two modes of air supply independent of a central air supply system.

To this end, the invention provides a ventilator comprising a first air circuit comprising a first pressure air source interface and a first flow regulating device connected in sequence; the second air circuit comprises a second pressure air source interface, a second flow regulating device and a second flow sensor which are sequentially connected; the third air path comprises a third pressure air source interface; a first inspiratory limb for delivering an inspiratory gas to a patient; a second suction branch comprising a gas compression device, the outlet of which is connected to the second flow regulating means and to a second flow sensor; the switching device comprises a first interface connected with the first air passage, a second interface connected with the second air passage and the first air suction branch, and a third interface connected with the third air passage and the second air suction branch, and has a first mode for connecting the first interface with the second interface and a second mode for connecting the first interface with the third interface; and an exhalation branch that manages the patient's exhaled gases.

In the present invention, the switching device has the first mode and the second mode, and the controller controls the switching device by judging the pressure value measured by the pressure sensor in the second air path, so that switching between the first mode and the second mode can be realized, and in the second mode, the inhaled air is supplied to the patient via the air compression device and the second flow sensor, so that on the one hand, switching can be performed according to the air supply source and the mixed air of the required oxygen concentration can be timely supplied, and on the other hand, the second flow regulating device can be shared, so that the increase in cost can be suppressed. In addition, the ventilator can be independent of a central air supply system.

In addition, in the breathing machine related to the invention, the second air circuit further comprises a pressure sensor for detecting the air pressure at the interface of the second pressure air source; and a controller that controls the switching device based on the measurement value of the pressure sensor, so that the switching device switches between the first mode and the second mode. The controller is thereby able to control the switching device by determining the value of the pressure in the second gas path measured by the pressure sensor.

In addition, in the ventilator according to an aspect of the present invention, the switching device may include a pilot valve and a pneumatic three-way valve. In this case, the controller can conveniently switch the switching device between the first mode and the second mode by controlling the on and off of the pilot valve and the corresponding action of the pneumatic three-way valve.

In addition, in the ventilator according to the present invention, the second inspiration limb may further include a first mixing chamber, and the first mixing chamber may connect the third port with the third air path and the second inspiration limb. In this case, the gas of the first gas path and the gas of the third gas path can be better mixed through the first mixing chamber, thereby providing a mixed gas of, for example, a desired oxygen concentration.

In the ventilator according to the present invention, the second suction branch further includes a third flow rate adjustment device connected to the outlet of the gas compression device. In this case, since the third flow rate adjustment device can control the supplied gas, a prescribed amount of inhaled gas can be supplied to the patient.

In addition, in the ventilator according to the present invention, the second suction branch may further include a second mixing chamber. Thereby, the mixing effect of the mixed gas passing through the second mixing chamber can be further improved.

In the ventilator according to the present invention, the second suction branch further includes a third flow rate adjustment device including a voice coil motor. Thereby, the gas flowing through the second suction branch can be regulated more accurately.

In addition, in the ventilator according to the present invention, the first suction branch may further include a gas mixing device. Thus, the gas from the first gas path and the gas from the second gas path can be fully mixed by the gas mixing device, and the mixing effect of the mixed gas can be improved.

In addition, in the ventilator according to the present invention, the second suction branch may further include a check valve. In this case, the check valve can reduce the flow rate reflection shock, thereby ensuring the measurement accuracy of the gas flow rate of the second gas path.

In the ventilator according to the present invention, the gas compression device is a turbine. In this case, since the turbine is an air compression device having a low maximum static output pressure, it is possible to effectively suppress noise and provide a mixed gas satisfying, for example, a required oxygen concentration.

According to the invention, the breathing machine which is independent of a central air supply system, is switched according to the air supply source and timely provides mixed gas with required oxygen concentration can be realized.

Drawings

Fig. 1 is a system block diagram illustrating a ventilator according to an embodiment of the present invention.

Fig. 2 is a schematic diagram showing an inhalation flow path according to an embodiment of the present invention.

Fig. 3 is a schematic diagram showing a switching device according to an embodiment of the present invention.

Fig. 4 is a schematic diagram showing an inhalation flow path according to an embodiment of the present invention in a first mode.

Fig. 5 is a schematic view showing a state of the switching device shown in fig. 4.

Fig. 6 is a schematic diagram showing an inhalation flow path according to the embodiment of the present invention in the second mode.

Fig. 7 is a schematic view showing a state of the switching device shown in fig. 6.

Fig. 8 is a schematic diagram showing a modification 1 of the switching device according to the embodiment of the present invention.

Fig. 9 is a schematic diagram showing a modification 2 of the switching device according to the embodiment of the present invention.

The main reference numerals illustrate:

1 … ventilator, 2 … patient, 10 … inhalation branch, 20 … exhalation branch, 20 … controller, 11 … first air path, 12 … second air path, 13 … third air path, 14 … switching device, 15 … first inhalation branch, 16 … second inhalation branch, 17 … drive air path.

Detailed Description

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, the same members are denoted by the same reference numerals, and overlapping description thereof is omitted. In addition, the drawings are schematic, and the ratio of the sizes of the components to each other, the shapes of the components, and the like may be different from actual ones.

Fig. 1 is a system block diagram showing a ventilator 1 according to an embodiment of the present invention. As shown in fig. 1, in the present embodiment, the ventilator 1 may include an inhalation branch 10 and an exhalation branch 20. In the ventilator 1, the inspiratory limb 10 may be used to manage the inspiratory activity of the patient 2, enabling the patient 2 to be provided with a mixture of gases of a desired oxygen concentration. The exhalation branch 20 may be used to manage the exhalation behavior of the patient 2, and is capable of receiving the gas exhaled by the patient 2.

In addition, the exhalation limb 20 may also include a controller 30. The controller 30 may control the motion of the inspiratory limb 10 and the expiratory limb 20 through feedback from the inspiratory limb 10 and the expiratory limb 20 to assist the patient 2 in completing the inspiratory or expiratory behaviour.

In the present embodiment, in the inhalation flow path 10, the side closer to the patient 2 is referred to as "downstream side" or "downstream end", and the side farther from the patient 2 is referred to as "upstream side" or "upstream end". As will be described later, the upstream side of the inspiratory limb 10 is fed with various supply gases (e.g., high pressure oxygen, high pressure air, or ambient air) which, after mixing, are supplied to the patient 2 on the downstream side along the inspiratory limb 10.

Fig. 2 is a schematic diagram showing an air suction branch 10 according to an embodiment of the present invention. Fig. 3 is a schematic diagram showing the switching device 14 according to the embodiment of the present invention.

In this embodiment, as shown in fig. 2, the suction branch 10 may include a first air path 11, a second air path 12, a third air path 13, and a switching device 14. In the suction branch 10, the first air path 11, the second air path 12 and the third air path 13 can realize switching of different air paths and mixing of gases through a switching device 14.

In the present embodiment, the suction branch 10 further includes a first suction branch 15 and a second suction branch 16, and a first mode M1 in which the first air path 11 and the second air path 12 are connected to the first suction branch 15, and a second mode M2 (described later) in which the first air path 11 and the third air path 13 are connected to the second suction branch 16 can be realized by the switching device 14.

In this embodiment, as shown in fig. 2 and fig. 4 described later, the first gas path 11 may include a first pressure gas source interface 110 and a first flow rate adjusting device 111 connected in sequence. The first pressure gas source interface 110 may receive a first pressure gas source, i.e. the first pressure gas source interface 110 may be connected to a first pressure gas source, whereby the first pressure gas source is capable of supplying gas to the first gas circuit 11 via the first pressure gas source interface 110. In some examples, the first pressure gas source may be high pressure oxygen. Additionally, in some examples, the first pressure gas source received by the first pressure gas source interface 110 may be a bottled compressed gas.

In addition, in the first gas path 11, a gas such as high pressure oxygen may be delivered to the first flow rate adjusting device 111 through the first pressure gas source interface 110. The first flow regulating device 111 may regulate the flow of the second pressure gas source received by the first pressure gas source interface 110. In some examples, the first flow rate adjustment device 111 may be an electromagnetic proportional valve, but the present embodiment is not limited thereto, and for example, the first flow rate adjustment device 111 may be a valve group composed of on-off valves of different diameters, a valve island, or a flow control valve composed of a motor, or the like.

In addition, the first air path 11 may further include a first flow sensor 112. The first flow sensor 112 may measure the flow rate of the gas passing through the first flow regulating device 111. In some examples, the controller 30 may also control the first flow regulating device 111 based on the received flow value detected by the first flow sensor 112 to achieve accurate control of the flow. In some examples, the first flow sensor 112 may be an oxygen flow sensor, but the present embodiment is not limited thereto, and the first flow sensor 112 may be a flow sensor capable of achieving the same function.

In the present embodiment, the first air passage 11 may further include a first pressure adjusting device 113. First pressure regulator 113 may be disposed between first pressure gas source interface 110 and first flow regulator 111. In the first gas path 11, the first pressure regulating device 113 can regulate the pressure of the first pressure gas source, thereby being capable of providing a gas of a desired pressure. In some examples, the first pressure regulating device 113 may be a pressure regulating valve, but the present embodiment is not limited thereto, and the first pressure regulating device 113 may be a pressure regulating device capable of achieving the same function.

In this embodiment, as shown in fig. 2 and 4, the second air path 12 may include a second pressure air source interface 120, a second flow rate adjustment device 121, and a second flow rate sensor 122, which are sequentially connected. The second pressure gas source interface 120 may receive a second pressure gas source, i.e., the second pressure gas source interface 120 may be connected to a second pressure gas source, whereby the second pressure gas source is capable of supplying gas to the second gas circuit 12 via the second pressure gas source interface 120. In some examples, the second pressure gas source may be high pressure air or a high pressure heliox gas mixture. In some examples, the second pressure air source received by the second pressure air source interface 120 may be compressed air from a central air supply system, such as a central air supply system of a hospital.

In the second gas path 12, a gas, such as high pressure air, may be delivered to the second flow regulating device 121 via the second pressure gas source interface 120. The second flow regulator 121 may regulate the flow of the second pressurized gas source received by the second pressurized gas source interface 120. In some examples, the second flow rate adjustment device 121 may be an electromagnetic proportional valve, but the present embodiment is not limited thereto, and for example, the second flow rate adjustment device 121 may be a valve group composed of on-off valves of different diameters, a valve island, or a flow control valve composed of a motor, or the like.

In addition, the second flow sensor 122 may measure the flow rate of the gas passing through the second flow rate adjustment device 121. In some examples, the controller 30 may also control the second flow regulating device 121 based on the received flow value detected by the second flow sensor 122 to achieve precise control of flow. In some examples, the second flow sensor 122 may be an air flow sensor, but the present embodiment is not limited thereto, and the second flow sensor 122 may also be a flow sensor capable of achieving the same function.

In addition, in some examples, from the viewpoint of ensuring the oxygen concentration of the gas delivered to the patient 2, in the first mode M1, the difference between the volume of the passage from the first flow sensor 112 to the gas mixing device 150 (described later) and the volume of the passage from the second flow sensor 122 to the gas mixing device 150 is, for example, not more than 40mL, and the internal volume when the switching device 14 is switched to the first mode M1 is, for example, not more than 30mL.

As shown in fig. 4, the second gas circuit 12 also includes a pressure sensor 123 that detects the pressure of the gas at the second pressure gas source interface 120. That is, in the second pneumatic circuit 12, the pressure sensor 123 may measure the pressure of the second pressure air source received by the second pressure air source interface 120. In addition, pressure information (measured value) obtained by the pressure sensor 123 can be transmitted to the controller 30. Thereby, the controller 30 can control the switching device 14 based on the measured value of the pressure sensor 123, and switch the switching device 14 between the first mode M1 and the second mode M2. In addition, the pressure sensor 123 may be a pressure switch.

In addition, in the present embodiment, the second air path 12 may further include a second pressure regulating device 124. In addition, a second pressure regulating device 124 may be provided between the pressure sensor 123 and the second flow regulating device 121. The second pressure regulating device 124 may regulate the pressure of the second pressure gas source received by the second pressure gas source interface 120. In some examples, the second pressure regulating device 124 may be a pressure regulating valve, but the present embodiment is not limited thereto, and the second pressure regulating device 124 may be a pressure regulating device that performs the same function.

In this embodiment, the third air path 13 may include a third pressure air source interface 130. The third pressure gas source interface 130 may receive a third pressure gas source, i.e. the third pressure gas source interface 130 may be connected to a third pressure gas source, whereby the third pressure gas source is capable of supplying gas to the third gas circuit 13 via the third pressure gas source interface 130. In some examples, the third pressure air source may be ambient air. For example, the ambient air may be the ambient air of a hospital.

In addition, as shown in fig. 6 described later, the third air path 13 may also be provided with a filter device 131. The filtering device 131 may filter a third pressure air source, such as ambient air, received by the third pressure air source interface 130. Air meeting a prescribed standard, for example, a medical and health standard, can be generated by the filter device 131. In some examples, the filter device 131 may be a high efficiency air filter (HEPA).

In the present embodiment, let the air pressure of the first pressure air source supplied to the first pressure air source interface 110 be P1 (first pressure), the air pressure of the second pressure air source supplied to the second pressure air source interface 120 be P2 (second pressure), and the air pressure of the third pressure air source supplied to the third pressure air source interface 130 be P3 (second pressure), the air pressure P1 may be greater than the air pressure P3, and the air pressure P2 may be greater than the air pressure P3.

In the present embodiment, the gas having the gas pressure P1 or the gas pressure P2 is regarded as a high-pressure gas. Preferably, the air pressure P1 or the air pressure P2 ranges from 280kPa to 650kPa. In addition, the gas having the gas pressure P3 is regarded as a non-high pressure gas.

In addition, in the case where the second pressure air source interface 120 is connected to the central air supply system, the second pressure (air pressure P2) may vary with the pressure variation of the central air supply system. In the ventilator 1 according to the present embodiment, when the switching device 14 is in the first mode M1 and the air pressure P2 is lower than a predetermined value, the controller 30 can control the switching device 14 to switch from the first mode M1 to the second mode M2 (described later).

In this embodiment, the first inspiratory limb 15 may deliver an inspiratory gas (e.g., an oxygen-containing mixed gas) to a patient. In a case where the switching device 14 is in the first mode M1 (described later), the first air path 11 and the second air path 12 are connected (communicate) with the first inhalation branch 15, and in this case, the gas of the first air path 11 and the gas of the second air path 12 enter the first inhalation branch 15 to be mixed and supplied to the patient 2.

In addition, the first suction branch 15 may comprise a gas mixing device 150. In this case, it is possible to further mix the gas from the first gas passage 11 (first pressure gas source) with the gas from the second gas passage 12 (second pressure gas source) and obtain a mixed gas with improved mixing effect.

In this embodiment, the second inspiratory limb 16 may deliver an inspiratory gas (e.g., an oxygen-containing mixed gas) to the patient. In the case where the switching device 14 is in the second mode M2 (described later), the first gas path 11 and the third gas path 13 are connected (communicate) with the second inhalation branch 16, and in this case, the gas of the first gas path 11 and the gas of the third gas path 12 enter the second inhalation branch 16 to be mixed and supplied to the patient 2 (described later).

In this embodiment, the second suction branch 16 may also include a gas compression device 160 (see fig. 6). The gas compression device 160 is capable of compressing and pressurizing the gas flowing through the second suction branch 16. The maximum static output pressure of the gas compression apparatus 160 may be less than 210cmH20 (1 cmh20=0.098 kPa). Preferably, the maximum static output pressure of the gas compression apparatus 160 is less than 140cmH20, which may make the ventilator quieter, less power consuming, less bulky, and lighter in weight. In some examples, the gas compression apparatus 160 may be a gas compression apparatus having a lower maximum static output pressure, but the present embodiment is not limited thereto, and the gas compression apparatus 160 may be other devices performing the same function, such as a small compressor. Further, the gas compression apparatus 160 is preferably a turbine, in which case, since the turbine belongs to an air compression device having a low maximum static output pressure, it is possible to effectively suppress noise and provide a mixed gas satisfying, for example, a required oxygen concentration.

In addition, as shown in fig. 2 and 6, the outlet of the gas compression apparatus 160 is connected to the second flow rate adjustment device 121 and the second flow rate sensor 122. Specifically, the outlet of the gas compression apparatus 160 is connected to the second flow rate adjustment device 121, and the outlet of the gas compression apparatus 160 is connected to the second flow rate sensor 122. Thus, the gas passing through the gas compression device 160 can be controlled by the second flow rate adjustment device 121 of the second gas path 12 when flowing into the second gas path 12, and the gas passing through the gas compression device 160 can be supplied to the patient 2 through the second flow rate sensor 122.

In the present embodiment, the second suction branch 16 may further include a third flow rate adjustment device 161. The third flow regulating means 161 may control the flow of gas through the second suction branch 16. In some examples, the third flow regulating device 161 may include a voice coil motor, thereby enabling more precise control of the flow of gas through the second suction branch 16. Further, in some examples, the third flow rate adjustment device 161 may be a flow rate control valve composed of a motor, but the present embodiment is not limited thereto, and for example, the third flow rate adjustment device 161 may be a valve group composed of on-off valves of different paths, a valve island, an electromagnetic proportional valve, or the like.

In addition, the second suction branch 16 may also include a first mixing chamber 162. In the second mode M2, the switching device 14 may connect (communicate) the first air path 11 and the third air path 13 with the second air suction branch 16 through the first mixing chamber 162. That is, the gas supplied from the first gas passage 11 and the gas supplied from the third gas passage 13 are mixed in the first mixing chamber 162, whereby a mixed gas with improved mixing effect can be obtained, thereby supplying a mixed gas of a desired oxygen concentration to the patient 2. In some examples, where the gas supplied to the first gas circuit 11 is oxygen, the first mixing chamber 162 may be an oxygen mixing chamber.

In addition, the second suction branch 16 may further comprise a second mixing chamber 163. In some examples, the second mixing chamber 163 is configured to mix the mixed gas in the second mode M2 and pressurized by the gas compression apparatus 160 during inspiration. This can further improve the mixing effect of the mixed gas. In some examples, where the gas supplied to the first gas circuit 11 is oxygen, the second mixing chamber 163 may be an oxygen mixing chamber.

In addition, the second suction branch 16 may further comprise a one-way valve (also called check valve) 165 arranged before said second flow sensor 122. The check valve 165 is turned on in a direction along the upstream side to the downstream side of the second suction branch 16; the check valve 165 is closed in a direction along the downstream side to the upstream side of the second suction branch 16. Particularly, in the case of the first mode M1, the check valve 165 can effectively isolate the second air path 12 from the second air suction branch 16, so as to reduce the volume of the cavity of the second air path 12, match the impedance and the capacitance of the second air path 12 with those of the first air path 11, and reduce the flow velocity reflection impact of the gas of the first air path 11 on the second air path 12, thereby ensuring the measurement accuracy of the second air path 12.

Hereinafter, the switching device and the switching mode thereof are described in detail with reference to fig. 4 to 7. Fig. 4 is a schematic diagram showing an inhalation flow path according to an embodiment of the present invention in a first mode. Fig. 5 is a schematic view showing a state of the switching device shown in fig. 4. Fig. 6 is a schematic diagram showing an inhalation flow path according to the embodiment of the present invention in the second mode. Fig. 7 is a schematic view showing a state of the switching device shown in fig. 6.

As shown in fig. 4 and 6, the switching device 14 has a first mode M1 (see fig. 4) in which the first and second air paths 11 and 12 are connected to the first suction branch 15, and a second mode M2 (see fig. 6) in which the first and third air paths 11 and 13 are connected to the second suction branch 16.

Specifically, the switching device 14 includes a first port a connected to the first air passage 11, a second port B connected to the second air passage 12 and the first suction branch 15, and a third port C connected to the third air passage 13 and the second suction branch 16, and has a first mode M1 in which the first port a is connected to the second port B and a second mode M2 in which the first port B is connected to the third port C.

In some examples, the controller 30 may control the switching device 14 based on the measured value of the pressure sensor 123 disposed at the second gas path 12, thereby switching the switching device 14 between the first mode M1 and the second mode M2.

Specifically, the controller 30 may control the switching device 14 based on the measured value of the pressure sensor 123, in some cases (for example, in the case where the measured value of the pressure sensor 123 is in the normal range), so that the switching device 14 is in the first mode M1 (see fig. 4), when the first interface a is connected to the second interface B, that is, the first gas path 11 and the second gas path 12 are communicated with the first gas suction branch 15, and the supplied gas is delivered to the first gas suction branch 15 along the first gas path 11 and the second gas path 12 (in the direction of the straight arrow shown in fig. 4), and supplied to the patient 2, thereby enabling the patient 2 to obtain the mixed gas of, for example, a desired oxygen concentration.

In addition, the controller 30 may control the switching device 14 based on the measured value of the pressure sensor 123 in other cases (for example, in the case where the measured value of the pressure sensor 123 is out of the normal range) such that the switching device 14 is in the second mode M2 (see fig. 6), when the first port a is connected to the third port C, that is, the first gas path 11 and the third gas path 13 are communicated with the second gas suction branch 16, and the supply gas is delivered to the second gas suction branch 16 along the first gas path 11 and the third gas path 13 (in the direction of straight arrow as shown in fig. 6) and supplied to the patient 2, thereby enabling the patient 2 to obtain the mixed gas of, for example, a desired oxygen concentration.

Referring again to fig. 3, in this embodiment, the switching device 14 may include a pilot valve 141 and a pneumatic three-way valve 142. In addition, the pilot valve 141 may be controlled by the controller 30. The pilot valve 141 is connected to the pneumatic three-way valve 142, and different connection paths of the pneumatic three-way valve 142 can be realized in a pneumatic manner by controlling the pilot valve 141.

Specifically, the pilot valve 141 has a connection end E, F, wherein the connection end E can communicate with the first air passage 11 via the driving air passage 17; the connection end F is connected with the pneumatic three-way valve 142 and is used for driving the pneumatic three-way valve 142. In addition, the pneumatic three-way valve 142 includes an inlet end a and two outlet ends B, C. The air inlet end a of the pneumatic three-way valve 142 may be connected to the first air path 11, the air outlet end B may be connected to the second air path 12 and the first air suction branch 15, and the air outlet end C may be connected to the third air path 13 and the second air suction branch 16. Further, the present embodiment is not limited thereto, and for example, the air inlet end a of the pneumatic three-way valve 142 may be connected to the first air passage 11, the air outlet end B may be connected to the third air passage 13 and the second air suction branch 16, and the air outlet end C may be connected to the second air passage 12 and the first air suction branch 15. In this case, too, the switching device 14 can be switched between the first mode M1 and the second mode M2.

As shown in fig. 4, the driving gas path 17 may be a manifold of the first gas path 11 and supplied with gas from the first gas path 11. In the present embodiment, the driving gas path 17 is not limited to the first gas path 11, and may be the second gas path 12, or may be a separate gas path.

Additionally, in some examples, the pilot valve 141 is, for example, a solenoid valve that may be turned on or off under the influence of the controller 30. After the pilot valve 141 is turned on, the pressure-regulated first pressure air source from the first air path 11 drives the pneumatic three-way valve 142 via the driving air path 17, so that the first interface a and the second interface B of the switching device 14 are connected, that is, the first air path 11 and the second air path 12 are connected (communicated) with the first air suction branch 15, and therefore the air of the first air path 11 and the air of the second air path 12 are converged and enter the first air suction branch 15. At this time, the switching device 14 is in the first mode M1 (see fig. 4). In addition, when the pilot valve 141 is closed, the driving air passage 17 is disconnected from the pneumatic three-way valve 142, and the pneumatic three-way valve 142 connects (communicates) the first air passage 11 and the third air passage 13 with the second air suction branch 16 under the action of the spring force, that is, the air in the first air passage 11 and the air in the third air passage 13 are converged and enter the second air suction branch 16. At this time, the switching device 14 is in the second mode M2 (see fig. 6).

As described above, in the present embodiment, the controller 30 can control the switching device 14 based on the measured value of the pressure sensor 123 such that the switching device 14 can switch between the first mode M1 in which the first gas passage 11 is connected to the second gas passage 12 and the first suction branch 15 and the second mode M2 in which the first gas passage 11 is connected to the third gas passage 13 and the second suction branch 16, thereby making it possible to switch according to the supply gas source and to timely supply the mixed gas of, for example, a desired oxygen concentration.

In some examples, when the controller 30 detects that the value measured by the pressure sensor 123 satisfies a prescribed value (for example, the pressure value is greater than 200 kPa), when the controller 30 turns on the pilot valve 141, the gas driving the gas path 17 directly pushes the internal spring of the pneumatic three-way valve 142, for example, to communicate the gas inlet end a with the gas outlet end B of the pneumatic three-way valve 142, so that the switching device 14 is in the first mode M1 (see fig. 4) in which the first gas path 11, the second gas path 12, and the first gas suction branch 15 are connected (communicated). In other examples, when the controller 30 detects that the value measured by the pressure sensor 123 does not satisfy the prescribed value (for example, the pressure value is less than or equal to 200 kPa), the controller 30 closes the pilot valve 141, at which time the gas driving the gas path 17 is disconnected from the pneumatic three-way valve 142, the internal spring of the pneumatic three-way valve 142 is restored to the original state, the gas inlet end a of the pneumatic three-way valve 142 is communicated with the gas outlet end C, and thus the switching device 14 is placed in the second mode M2 (see fig. 6) in which the first gas path 11 is connected to the third gas path 13 and the second gas suction branch 16. Therefore, the mixed gas with the required oxygen concentration can be switched according to the gas supply source and provided in time.

In particular, when the switching device 14 of the suction branch 10A is in the first mode M1, the first interface a of the switching device 14 is connected to the second interface B, and the first air path 11 and the second air path 12 are in communication with the first suction branch 15. The check valve 165 is closed to prevent gas from the second gas path 12 from entering the gas line of the second inspiratory limb 16, and supply gas is supplied to the patient 2 via the first gas path 11 and the second gas path 12 to the first inspiratory limb 15. When the switching device 14 is in the second mode M2, the first port a of the switching device 14 is connected to the third port C, that is, the first air path 11 is connected to the third air path 13 and the second air suction branch 16, and the check valve 165 is turned on, so that the second flow rate adjusting device 121 is turned off. In this case, the gas of the first gas circuit 11 and the gas of the third gas circuit 13 are led into the second suction branch 16 and are supplied to the patient 2 at least via the gas compression device 160 of the second suction branch 16 and the second flow sensor 122 of the second gas circuit 12 in sequence. In this case, the second suction branch 16 can share the second flow sensor 122 with the second air passage 12, whereby an increase in cost can be effectively suppressed. In addition, a central air supply system may be eliminated.

The switching device 14 of the present embodiment is not limited to the above-described example, and a modification of the switching device 14 of the present embodiment is described below with reference to fig. 8 and 9.

Fig. 8 is a schematic diagram showing a modification 1 of the switching device according to the embodiment of the present invention. As shown in fig. 8, the switching device 14 may be an electromagnetic three-way valve 14A, instead of the pilot valve 141 and the pneumatic three-way valve 142 described above. In this case, by directly controlling the electromagnetic three-way valve 14A by the controller 30, communication between the air inlet end A1 and the air outlet end B1 or the air outlet end C1 of the electromagnetic three-way valve 14A can also be achieved, thereby achieving switching of the switching device 14 between the first mode M1 and the second mode M2. The driving gas path 17 of the present embodiment is omitted by using the electromagnetic three-way valve 14A.

Fig. 9 is a schematic diagram showing a modification 2 of the switching device according to the embodiment of the present invention. As shown in fig. 9, the switching device 14 may be a motor-driven three-way valve 14B for replacing the pilot valve 141 and the pneumatic three-way valve 142 described above. That is, the switching device 14 may be a three-way valve controlled by a motor. In this case, the communication between the inlet end A2 and the outlet end B2 or the outlet end C2 of the motor-driven three-way valve 14B can also be achieved by directly controlling the motor-driven three-way valve 14B by the controller 30, thereby achieving switching of the switching device 14 between the first mode M1 and the second mode M2. In addition, the driving gas path 17 of the present embodiment is omitted by driving the three-way valve 14B using a motor.

While the invention has been described in detail in connection with the drawings and embodiments, it should be understood that the foregoing description is not intended to limit the invention in any way. Modifications and variations of the invention may be made as desired by those skilled in the art without departing from the true spirit and scope of the invention, and such modifications and variations fall within the scope of the invention.

Claims (13)

1. A ventilator, characterized in that: the ventilator includes:

the first air path comprises a first pressure air source interface and a first flow regulating device which are sequentially connected;

the second air circuit comprises a second pressure air source interface, a second flow regulating device and a second flow sensor which are sequentially connected;

the third air path comprises a third pressure air source interface;

a first inspiratory limb for delivering an inspiratory gas to a patient;

a second suction branch comprising a gas compression device, the outlet of which is connected to the second flow regulating means and to a second flow sensor;

the switching device comprises a first interface connected with the first air passage, a second interface connected with the second air passage and the first air suction branch, and a third interface connected with the third air passage and the second air suction branch, wherein the switching device is provided with a first mode for connecting the first interface with the second interface to realize the connection of the first air passage and the second air passage with the first air suction branch, and a second mode for connecting the first interface with the third interface to realize the connection of the first air passage and the third air passage with the second air suction branch; wherein the second flow sensor is shared in the first mode and the second mode; and in the first mode, the second flow sensor is configured to detect a gas flow of the second gas path; in the second mode, the second flow sensor is used for detecting the flow of the mixed gas of the first gas path and the third gas path; and

an exhalation limb that manages the patient's exhalation gases.

2. The ventilator according to claim 1, wherein:

the first suction branch further comprises a gas mixing device.

3. The ventilator according to claim 2, wherein:

the first gas circuit further includes a first flow sensor for measuring the flow of gas through the first flow regulating device.

4. A ventilator according to claim 3, characterized in that:

in the first mode, a difference between a volume of a passage from the first flow sensor to the gas mixing device and a volume of a passage from the second flow sensor to the gas mixing device is not more than 40ml, and an internal volume when the switching device is switched to the first mode is not more than 30ml.

5. The ventilator of any of the preceding claims 1-4 wherein:

the second gas circuit further comprises a pressure sensor for detecting the gas pressure at the interface of the second pressure gas source; and

and a controller that controls the switching device based on the measurement value of the pressure sensor, so that the switching device switches between the first mode and the second mode.

6. The ventilator of any of the preceding claims 1-4 wherein:

the switching device further comprises a pilot valve and a pneumatic three-way valve.

7. The ventilator of any of the preceding claims 1-4 wherein:

the second suction branch further comprises a first mixing cavity, and the first mixing cavity connects the third interface with the third air path and the second suction branch.

8. The ventilator of any of the preceding claims 1-4 wherein:

the second suction branch further comprises a third flow regulating device connected to the outlet of the gas compression apparatus.

9. The ventilator according to claim 8, wherein:

the third flow regulating device comprises a voice coil motor.

10. The ventilator of claim 1, 2, 3, 4 or 9, wherein:

the second suction branch further comprises a second mixing chamber arranged after the gas compression device.

11. The ventilator of claim 1, 2, 3, 4 or 9, wherein:

the gas compression apparatus is a turbine.

12. The ventilator of claim 1, 2, 3, 4 or 9, wherein:

the first air circuit further comprises a first pressure regulating device for regulating the pressure of the first pressure air source.

13. The ventilator of claim 1, 2, 3, 4 or 9, wherein:

the third air path further includes a filter device for filtering the third pressure air source received by the third pressure air source interface.