JPH09285543A - Flow control method and device for breathing gas, and breathing gas supply device having the same device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flow control device and a method to be applied to a breathing gas supply device in which the device can be compact and light. SOLUTION: An oxygen generating device 1 is provided with an oxygen container 4 and a pressure reducing valve 5, where a throttle valve for flow control is omitted to achieve compactness. A flow control device 2 is composed in such a way that it can be operated at hand. The flow control device 2 is provided with plural branch passages 16, 17. Solenoid valves 18, 20 are provided in the respective branch passages 16, 17. For the soleoid valves 18, 20, those in which throttles 19, 21 are integrally assembled are used. Total flow of oxygen flowing through the branch passages 16, 17 can be changed by actuation of the solenoid valve 18 only, the solenoid valve 20 only, or both the solenoid valves 18, 20 simultaneously. An oxygen supply device which is so compact as to be suitable to be carried, and which can be easily operated at hand by a patient can thus be provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a breathing gas supply device and a flow rate adjusting device and method applied to the device. In particular, the present invention relates to a breathing gas supply apparatus applicable as a portable oxygen supply apparatus used by patients with respiratory diseases, and a flow rate adjusting apparatus and method for the apparatus.

[0002]

2. Description of the Related Art Oxygen therapy by inhaling oxygen has been conventionally performed in order to improve respiratory failure in patients with chronic respiratory diseases. Oxygen therapy is not performed only in a specific place such as a hospital, but rather needs to be performed in every scene of a patient's daily life. Because when you go out for shopping or when you're out, rather than when you're at home
Need to inhale oxygen. This is because, even if the burden of walking or the like is added to the body, the breathing stability can be secured by the inhaled oxygen. Therefore, it is necessary to reduce the size and weight of the oxygen supply device so that the patient can carry it.

A conventional oxygen supply apparatus includes an oxygen cylinder, a flow rate adjusting mechanism for extracting high-pressure oxygen filled in the oxygen cylinder by adjusting it to a predetermined prescribed flow rate, and a prescribed flow rate of oxygen in a patient's nostril. For example, it is equipped with a nasal cannula to supply to the mouth and mouth. In order to make such a device portable for patients, first, it is essential to reduce the size and weight of the oxygen cylinder. However, reducing the size and weight of the oxygen cylinder imposes a limit on the amount of oxygen that can be filled in the cylinder, which makes continuous use for a long time difficult.

Therefore, as an improved oxygen supply device, a respiratory gas supply device is provided in which oxygen is supplied only at the time of inhalation in response to a patient's breathing cycle, and unnecessary oxygen consumption due to continuous oxygen supply is prevented. Has been proposed (see Japanese Patent Laid-Open No. 5-92038). In the method in which the patient supplies oxygen only at the time of inhalation, useless consumption of oxygen is prevented, so that the oxygen cylinder can be made smaller and lighter.

[0005]

However, in order to downsize the oxygen supply device, not only the cylinder but also the flow rate adjusting mechanism must be downsized. The conventional flow rate adjusting mechanism is generally configured as disclosed in Japanese Utility Model Publication No. 5-38750. That is, the pressure reducing valve attached to the cylinder reduces the pressure of the high-pressure gas to a constant pressure, and further regulates it to a prescribed constant flow rate by a variable flow rate throttle valve (flow rate adjusting valve).

As described above, since the flow rate adjusting mechanism is constituted by the pressure reducing valve and the throttle valve with variable flow rate, there is a problem that it is difficult to reduce the size and weight. So this invention
It is an object of the present invention to provide a small-sized and lightweight flow rate adjusting device and method applied to a breathing gas supplying device such as an oxygen supplying device. Another object of the present invention is to provide a flow rate adjusting device which is not attached to the cylinder but is provided separately from the cylinder and is easy for the patient to adjust.

Another object of the present invention is to provide a small-sized and lightweight breathing gas supply device including the above flow rate adjusting device.

[0008]

According to the first aspect of the present invention,
It has an inlet through which breathing gas of a constant pressure is introduced, an outlet for delivering the breathing gas to a predetermined device, and a flow path for guiding the breathing gas introduced from the inlet to the outlet. The flow path includes a plurality of branch paths that branch into a plurality of pieces and join again, and each of the branch paths includes,
A flow path opening / closing means having a unique flow path throttling resistance different for each branch path is inserted, and by selecting the operating state of the plurality of flow path opening / closing means, the breathing gas discharged from the outlet is And a switching means for switching a flow rate, which is a flow rate adjusting device for breathing gas.

According to the above arrangement, which of the flow path opening / closing means inserted in each of the plurality of branch paths is in an operable state, and which flow path opening / closing means is in an inoperable state. By switching between these, the total flow rate of the breathing gas flowing through the plurality of flow paths can be adjusted. According to a second aspect of the present invention, in the breathing gas flow rate adjusting device according to the first aspect, a pressure for detecting the pressure of the breathing gas flowing through an arbitrary portion of the flow passage located on the downstream side of the flow passage opening / closing means. A flow rate adjusting device, further comprising: a detection unit; and an opening / closing control unit that controls opening / closing of a flow path opening / closing unit in an operable state by a switching unit according to a pressure detected by the pressure detection unit. is there.

According to the above construction, the flow rate of the breathing gas delivered from the outlet is adjusted by the switching means, and the adjusted flow rate of the breathing gas is adjusted at a predetermined timing according to the pressure detected by the pressure detecting means. It can be sent out or stopped. The invention according to claim 3 is the invention according to claim 2.
In the breathing gas flow rate adjusting device described above, the pressure detecting means includes a diaphragm type pressure detector having a pressure detecting passage branched from a flow passage, and a diaphragm attached to the passage. It is a flow rate adjusting device.

By thus adopting the diaphragm type pressure detector, the pressure detector can be downsized, and the flow rate adjusting device can be downsized. According to a fourth aspect of the invention, in the breathing gas flow rate adjusting device according to the second or third aspect, the flow path opening / closing means includes an electromagnetic valve opened / closed by an electric signal from the opening / closing control means. It is a flow rate adjusting device.

According to the above construction, the flow path opening / closing means can be controlled by an electric signal, and the device can be made safe and easy to operate. The invention according to claim 5 is the invention according to claim 4.
In the above-described breathing gas flow rate adjusting device, the flow path opening / closing means includes a direct-current excitation type electromagnetic valve.

With this configuration, the power consumption is low,
A flow rate adjusting device suitable for carrying can be provided. According to a sixth aspect of the present invention, in the breathing gas flow rate adjusting device according to the fourth or fifth aspect, the solenoid valve is a normally closed solenoid valve that is closed when not energized. Is.

According to this structure, the solenoid valve is closed when the power is not supplied, and when the power supply battery of the flow rate adjusting device is exhausted, the breathing gas does not flow unnecessarily. The invention according to claim 7 is characterized in that a generating means for generating a breathing gas having a constant pressure and an inlet is connected to the generating means.
7. A breathing gas supply device comprising the flow rate adjusting device according to any one of items 1 to 6.

According to an eighth aspect of the present invention, in the breathing gas supply apparatus according to the seventh aspect, the means for generating a breathing gas having a constant pressure is a container filled with oxygen compressed to a high pressure.
A breathing gas supply device comprising: a pressure reducing valve provided at an oxygen outlet of the container.

According to each of the above-mentioned configurations, it is possible to provide a small-sized and portable breathing gas supply device. In particular, since both the breathing gas generating means and the flow rate adjusting device can be miniaturized, the device is convenient for patients with respiratory diseases to carry. According to a ninth aspect of the present invention, a plurality of branch passages are formed in the flow passage extending from the inlet to the outlet so as to be branched into a plurality of branches and merged again, and each branch passage has a specific flow resistance different from each other. In addition, the flow rate adjusting method is characterized in that opening / closing means for opening / closing the branch path is provided and the opening / closing state of each branch path is switched to switch the flow rate of the gas delivered from the outlet.

According to the above construction, it is possible to provide a flow rate adjusting method which facilitates the switching operation.

[0018]

An embodiment of the present invention will be described below in detail with reference to the drawings. FIG.
It is a block diagram which shows the structure of the oxygen supply apparatus concerning one Embodiment of this invention. The oxygen supply device has an oxygen generating device 1 for flowing oxygen at a constant pressure, a flow rate adjusting device 2 connected to the oxygen generating device 1 for adjusting the flow rate of oxygen flowing out of the oxygen generating device 1, and a flow rate. A nasal cannula 3 is provided for supplying the oxygen, the flow rate of which is adjusted by the adjusting device 2, to, for example, the nostrils of a patient with respiratory disease. If oxygen is delivered to the patient's mouth, nasal cannula 3
Instead, a mouth cannula is attached. The device worn by the patient such as the nasal cannula 3 may be any device as long as it can supply oxygen in an unsealed state, that is, in a state open to the atmosphere.

The oxygen generator 1 includes an oxygen container 4 and a pressure reducing valve 5 provided at the oxygen outlet of the oxygen container 4. The oxygen container 4 is of a size that can be carried by the patient,
For example, a container with a capacity of 1.1 liter is used. The oxygen container 4 is filled with oxygen at a high pressure of, for example, 150 kg / cm ² . A pressure reducing valve 5 is attached to the outlet of the oxygen container 4. The pressure reducing valve 5 is a device for reducing the pressure of the high-pressure oxygen in the oxygen container 2 to a constant pressure and causing the oxygen to flow out. A pressure gauge 6 for displaying the pressure in the oxygen container 4 may be added to the pressure reducing valve 5.

Further, a throttle 7 for regulating the outflow rate of oxygen decompressed by the pressure reducing valve 5 may be provided.
Unlike the throttle valve for adjustment that can change the flow rate described in the prior art, the throttle 7 has a simple structure and a small size. The throttle 7 is usually formed integrally with the pressure reducing valve 5, has a simple structure, and does not have a large shape.

The flow rate adjusting device 2 includes an inlet 11 and an outlet 1.
2 is provided, and oxygen having a constant pressure is introduced into the inlet 11 from the oxygen generator 1. The oxygen generator 1 and the flow rate controller 2 are connected by, for example, a pipe having a predetermined length.
The flow rate adjusting device 2 is a small device that can be easily operated by the patient, for example, using a battery as a power source.

Oxygen introduced from the inlet 11 passes through the flow path 13
Is led to the exit 12. The flow passage 13 includes a parallel flow passage portion 14. In the parallel flow path portion 14, a plurality of flow paths, in this embodiment, three branches are provided, and three branch paths 1 are provided.
5, 16 and 17 extend in parallel and join again. An electromagnetic valve 18 is inserted in the branch passage 16. A throttle 19 is integrally incorporated in the solenoid valve 18. The throttle 19 has a unique flow passage throttle resistance Ra. Therefore, when the solenoid valve 18 is open, the flow rate of oxygen through the branch 16 is
It is limited to a fixed amount a determined by the resistance value Ra of the diaphragm 19.

An electromagnetic valve 20 is also inserted in the branch passage 17, as in the branch passage 16. A throttle 21 is also integrated with the solenoid valve 20. The diaphragm 21 has a unique channel restricting resistance Rb different from the channel restricting resistance Ra of the diaphragm 19. In this embodiment, the resistance value Ra of the diaphragm 19 is set relatively small, and the resistance value Rb of the diaphragm 21 is set relatively large.

Since the solenoid valves 18 and 20 both have the advantage that they consume less power and are suitable for carrying, a DC excitation type is used, and a normally closed type that is closed when not energized. There is. However, the solenoid valves 18 and 2
Zero does not necessarily have to be a DC excitation type, and may not be a normally closed type.

A manually operated stop valve 22 is provided in the branch passage 15.
Is inserted. The stop valve 22 is opened when oxygen is manually supplied, for example, when the battery of the flow rate control device 2 is dead and the electromagnetic valves 18 and 20 are closed. Therefore, the stop valve 22 is normally closed. The stop valve 22 may be omitted for a simpler configuration.

A pressure detecting passage 23 is branched into the passage 13 located on the downstream side of the parallel passage portion 14, and the passage 23 has a pressure detector 25 including a diaphragm 24.
Is provided. The pressure detector 25 determines the start time of oxygen delivery from the outlet 12 to the nasal cannula 3 based on the change in pressure of the diaphragm 24, which is a component of the pressure detector 25. That is, the pressure in the flow path 13 decreases due to the negative pressure associated with the inspiration of the patient. The pressure detector 25 uses the diaphragm 24 to detect the pressure change.

The pressure change detected by the pressure detector 25 is
It is given to the control circuit 26. The control circuit 26 includes an electronic circuit including a microcomputer, for example, and outputs an excitation signal to the solenoid valves 18 and 20 at a cycle and timing described in detail later to start the delivery of oxygen. The solenoid valves 18 and 20 are opened while the excitation signal is applied (while the excitation signal is high), and closed when the excitation signal is not applied (when the excitation signal is low).

The flow rate adjusting device 2 further includes an operating section 27.
Is provided. The operation unit 27 is provided with three switches for switching the flow rate in three stages. That is, the multi-switch 2 for setting the maximum flow rate
8. A middle switch 29 for reducing the flow rate to a standard amount and a small switch 30 for reducing the flow rate. These switches 28, 29, 30 are provided on the surface of, for example, the housing of the device 2 and are manually operated by the patient using the oxygen generator 1.

Each switch 28 provided on the operation unit 27,
The signals from 29 and 30 are given to the control circuit 26. The control circuit 26 generates a control signal based on the signal from the pressure detector 25 and the signal from the operation unit 27. Then, the control signal is given to the solenoid valves 18 and 20 as an excitation signal. FIG. 2 shows the solenoid valve 1 according to the switching of the switches 28, 29, 30 provided on the operation unit 27.
It is a figure which shows the relationship of the change of the control signal to 8 and 20, and the flow rate change accompanying it.

In particular, FIG. 2A shows an example of a logic circuit included in the control circuit 26, and FIG. 2B shows a list of flow rate changes due to switching of the switches 28, 29 and 30. It has been forgotten. Referring to FIG. 2, when the multi-switch 28 of the operation unit 27 is turned on, the signal states of the terminals A and B both become high. When the middle switch 29 is turned on, the terminal A goes low and the terminal B goes high. When the small switch 30 is further turned on, the terminal A is high and the terminal B is low.

The state of the terminals A and B is one input of the two-input AND gates 31 and 32, respectively, and a control signal is given to the other input of the AND gates 31 and 32. Therefore, if the multi-switch 28 is turned on and both terminals A and B are in the high state, depending on whether the control signal is low or high,
The solenoid valves 18 and 20 are turned on / off. Therefore, the oxygen flow rate through the parallel flow path portion 14 (see FIG. 1) is switched to 0 or a + b according to the control signal. Here, a is the flow rate limited by the throttle 19 provided in the solenoid valve 18, as described above, and b is the throttle 2 provided in the solenoid valve 20.
The flow rate is limited by 1.

When the middle switch 29 is on,
The output of the AND gate 31 is always low, and the solenoid valve 18
Is disabled. Therefore, the solenoid valve 18 is always closed. In this state, when the control signal changes to low / high, only the solenoid valve 20 is switched off / on. Therefore, the total flow rate of oxygen flowing through the parallel flow path portion 14 is switched between 0 and b according to the control signal.

Further, when the small switch 30 is on, the terminal B is in the low state, the output of the AND gate 32 is always low, and the solenoid valve 20 is inoperable. For this reason,
Only the solenoid valve 18 is turned off / on according to the low / high level of the control signal. Therefore, the total flow rate of oxygen flowing through the parallel flow path portion 14 in this case is switched between 0 and a. As mentioned above,
By switching the switches 28, 29, 30 provided on the operation unit 27, when the solenoid valves 18, 20 are opened by the control signal, the total flow rate of oxygen delivered from the outlet 12 is either a + b, b or a. You can switch to

Next, the control signal output by the control circuit 26 will be described. FIG. 3 is a timing chart showing the relationship between the breathing pattern, the output of the pressure detector 25, the control signal and the oxygen flow rate delivered from the outlet 12. Also,
FIG. 4 is a flow chart showing the control contents for obtaining the timing of FIG. 3 by the control circuit 26. First, a description will be given with reference to FIG. Generally, it is said that there is a 1: 2 relationship between inspiration time and expiration time. The pressure detector 25 changes to low at the start of intake. Therefore, the pressure detector 25
The inspiration time can be estimated by measuring the time from the low edge to the low edge and obtaining the time that is one-third of the time. In the control shown in FIG. 4, the inspiratory time in the subsequent breathing pattern is calculated from the preceding two breathing patterns.

Then, during the estimated inspiration time, the control signal is made high, and the solenoid valve 18 and / or the solenoid valve 20 is turned on so that a predetermined amount of oxygen is delivered during the inspiration period. Note that, as described above, the oxygen flow rate to be sent is determined by switching the switches 28, 29, 30 provided in the operation unit 27, regardless of the control signal. Next, the control content will be described with reference to FIG.

As described above, the control circuit 26 includes a microcomputer, for example, and is provided with a timer and a memory. When the control starts, first the pressure detector 2
It is determined whether a low edge is output from 5 (step S1). When the low edge from the pressure detector 25 is detected, the time measured by the timer T is read. When the timer is not started in the initial state, the clocked time is 0, so 0 may be read, or a preset time T ₀ may be used instead of ₀ (step S2).

When the measured time is read, the timer is reset and restarted (step S2). Then
The read time T (or T ₀ ) is stored in the area M ₁ of the memory. At this time, the value stored in the area M ₁ is moved to the area M ₂ . And areas M ₁ and M
Each value stored in ₂ and added, it is divided by 2,
Further, the intake time T _C is calculated by dividing it by 3. This inspiration time T _C is an estimated inspiration time obtained by the preceding two breathing patterns. This time T _C is stored in the work area M ₃ as the set time (step S3).

Such calculation is almost instantaneously performed in the microcomputer. Then, a high control signal is output (step S4). The output of the high control signal is output almost in response to the low edge output from the pressure detector 25 because the processing of steps S2 and S3 is almost instantaneously ended as described above. Then, a high control signal is output until the set time T _C has elapsed (step S5).
When the set time T _C , that is, the estimated intake time elapses,
The control signal is made low (step S6).

The above processing is repeated, and as shown in FIG. 3, a predetermined flow rate of oxygen is delivered from the outlet 12 to the nasal cannula 3 only during the inspiration period. FIG. 5 is a timing chart for explaining another control content that can be performed by the control circuit 26. As shown in FIG. 5, oxygen may be delivered for a short time T _S immediately after the start of the inspiration time of the breathing pattern. Also in this case, the oxygen delivery amount is determined by switching the switches 28, 29, 30 provided in the operation unit 27, regardless of the control content.

In the control shown in FIG. 5, oxygen may be delivered within all inspiration times of the breathing pattern (see flow path opening / closing pattern 1), or two inspiration periods when the breathing pattern continues three times. It is also possible to send oxygen to the air and not send oxygen for the remaining one inspiration period (see the flow path opening / closing pattern 2). Alternatively, oxygen may be supplied only during one inspiration period of the three breathing patterns (see flow path opening / closing pattern 3).

In the above embodiment, as shown in FIG.
An example has been shown in which the parallel flow path portion 14 is provided with three branch paths 15, 16 and 17, and opening / closing of the two branch paths 16 and 17 is controlled. Instead of this, there may be three branch paths whose opening and closing are controlled. The throttle resistance value of the solenoid valve inserted in the third branch passage is the throttle valve 19 of the solenoid valve 18.
Resistance value Ra or resistance value Rb of the diaphragm 21 of the solenoid valve 20
It is preferable to make it different. This is because the flow rate can be switched in multiple stages.

As described above, a relatively large flow rate of oxygen is supplied only during the initial short period of the inhalation period, not the entire inhalation period in the respiratory cycle, and the oxygen supply performed by the above method is performed by the patient. It is also possible to perform control so as to adjust the total supply amount of oxygen by thinning out at a fixed rate instead of performing it for each intake. In such control, oxygen is supplied only for a short time, and the number of times of supplying oxygen is thinned out than the number of times of inhaling. Therefore, it is necessary to make the number of times of supplying oxygen and the time thereof correspond to the number of times of inhalation of a patient. Alternatively, the flow rate of oxygen supplied may not match the flow rate of oxygen inhaled by the patient.

In the above embodiment, the oxygen supply device is taken up for description. However, the present invention can be applied not only to the oxygen supply device but also to a gas supply device for breathing in general.

[0044]

According to the invention of claim 1 or 9,
It is possible to provide an apparatus or method for adjusting the flow rate of a breathing gas that facilitates switching control of the flow rate. According to the invention described in claim 2,
It is possible to provide a flow rate adjusting device that supplies the flow rate at a predetermined timing according to the change in the pressure of the breathing gas and stops the supply while the flow rate is switched by the switching means.

According to the third aspect of the present invention, the structure of the pressure detector can be simplified, and the flow rate adjusting device is small as a whole. According to the invention as set forth in claim 4, since the flow path can be opened and closed by an electric signal, the flow rate adjusting device can be controlled easily and safely. According to the fifth aspect of the invention, it is possible to provide a flow rate adjusting device which has low power consumption of the solenoid valve and is suitable for carrying.

According to the sixth aspect of the present invention, it is possible to provide a flow rate adjusting device that does not wastefully deliver the breathing gas when the power supply battery of the flow rate adjusting device is exhausted. Claim 7 or 8
According to the described invention, it is possible to provide a small-sized breathable gas supply device suitable for carrying.

[0047]

【The invention's effect】 [Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an oxygen supply device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between a change in a control signal to a solenoid valve due to switching of a switch and a change in flow rate accordingly.

FIG. 3 is a timing chart showing a relationship among a breathing pattern, a detected pressure, a control signal, and an oxygen flow rate when a predetermined oxygen supply control is performed.

FIG. 4 is a flowchart showing the control contents for obtaining the timing of FIG.

FIG. 5 is a timing chart showing a relationship between a breathing pattern and a flow path opening / closing pattern when performing control content different from that of FIG.

[Explanation of symbols]

 1 Oxygen generator 2 Flow control device 3 Nasal cannula 4 Oxygen container 5 Pressure reducing valve 11 Inlet 12 Outlet 13 Flow path 15, 16, 17 Branch path 18, 20 Solenoid valve 19, 21 Throttle 23 Pressure detection passage 24 Diaphragm 25 Pressure detection Device 26 control circuit 27 operation unit 28, 29, 30 switch

Claims (9)

[Claims] 1. An inlet (1) into which breathing gas having a constant pressure is introduced.
1), an outlet (12) for delivering respiratory gas to a predetermined device, and a flow path (13) for guiding respiratory gas flowing from the inlet (11) to the outlet (12). The flow path (13) includes a plurality of branch paths (16, 17) that are branched into a plurality of pieces and join again, and each branch path (16, 17) has a branch. The flow path opening / closing means (18, 20) having unique flow path throttling resistances (19, 21) different for each of the paths (16, 17) is inserted, and further, a plurality of flow path opening / closing means (18, 20) ) By selecting the operating state
A switching device (28, 29, 30) for switching the flow rate of breathing gas delivered from an outlet (12), and a flow rate adjusting device for breathing gas. 2. A flow rate adjusting device for a breathing gas according to claim 1, wherein the flow path (13) is located downstream of the flow path opening / closing means (18, 20).
Pressure detecting means (25) for detecting the pressure of the breathing gas flowing through any part of the switch, and switching means (28, 2) depending on the pressure detected by the pressure detecting means (25).
A flow rate adjusting device further comprising: an opening / closing control means (26) for controlling opening / closing of the flow path opening / closing means (18, 20) which is in an operable state by the (9, 30). 3. The breathing gas flow rate adjusting device according to claim 2, wherein the pressure detecting means (25) includes a pressure detecting passage (23) branched from the flow passage (13) and the passage (23). ) Attached to the diaphragm (24) and a diaphragm type pressure sensor (25)
A flow rate adjusting device comprising: 4. The breathing gas flow rate adjusting device according to claim 2, wherein the flow path opening / closing means (18, 20) is opened / closed by an electric signal from an opening / closing control means (26). A flow control device characterized by including 18, 20). 5. The breathing gas flow rate adjusting device according to claim 4, wherein the flow path opening / closing means (18, 20) is a direct current excitation type solenoid valve (18, 20).
A flow rate adjusting device comprising: 6. The breathing gas flow rate adjusting device according to claim 4 or 5, wherein the solenoid valve (18, 20) is a normally closed solenoid valve (18, 20) that is closed when not energized. Flow rate adjusting device characterized by. 7. A flow regulating device (2) according to any one of claims 1 to 6, wherein a generating means (1) for producing a breathing gas having a constant pressure and an inlet (11) is connected to the generating means (1). ) And a breathing gas supply device. 8. The breathing gas supply apparatus according to claim 7, wherein the breathing gas generating means (1) having a constant pressure comprises a container (4) filled with oxygen compressed to a high pressure, and a container (4). (4) A pressure reducing valve (5) provided at the oxygen outlet of the breathing gas supply device. 9. A plurality of branch paths are formed in the flow path from the inlet to the outlet, which branch into a plurality of branches and merge again, and each branch path has a specific flow resistance different from each other.
Further, a flow rate adjusting method characterized in that an opening / closing means for opening / closing the branch path is provided and the opening / closing state of each branch path is switched to switch the flow rate of the gas delivered from the outlet.