JP2008036349A - Feeder for oxygen-enriched gas - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a feeder for oxygen-enriched gas, capable of not only controlling the flow rate of the oxygen-enriched gas at a high precision but also having superior safety. <P>SOLUTION: This feeder for oxygen-enriched gas is provided with an oxygen-enriched gas supply source 100, a flow rate setting means 209, a proportional control valve 201, a pressure detecting means 203, a flow rate detecting means 204, and a valve opening control means 211; when a pressure P<SB>DET</SB>detected by the pressure detecting means 203 is lower than a first upper limit pressure P<SB>MAX1</SB>, executes a feeding operation feeding the oxygen-enriched gas while controlling the valve opening of the proportional control valve and, when the pressure P<SB>DET</SB>detected by the pressure detecting means 203 is higher a first upper limit pressure P<SB>MAX1</SB>, executes a cutoff operation of completely closing the proportional control valve. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an oxygen-enriched gas supply device for supplying an oxygen-enriched gas having an increased oxygen concentration. In particular, the present invention relates to an oxygen-enriched gas supply device that can be suitably incorporated into a medical oxygen concentrator.

  Oxygen inhalation therapy is known as an effective method for treating respiratory diseases such as emphysema and bronchitis. Oxygen inhalation therapy allows patients to inhale oxygen-enriched gas with increased oxygen concentration, thereby supplying oxygen to tissue cells that are deficient in oxygen and alleviating the pain felt by patients, such as breathlessness. . Since 1985, medical insurance has been applied to home oxygen inhalation therapy, and an increasing number of patients receive oxygen inhalation therapy at home. Under these circumstances, the demand for medical oxygen concentrators using pressure fluctuation adsorption separation, which can generate oxygen-enriched gas from ambient air (raw air) and supply it to patients, has steadily increased. It is coming.

  A general medical oxygen concentrator using the pressure fluctuation adsorption separation method is generated by an oxygen-enriched gas generating and generating means for generating and generating oxygen-enriched gas by increasing the oxygen concentration of raw material air, and an oxygen-enriched gas generating means. A storage tank for storing the oxygen-enriched gas, a flow rate setting means for setting a flow rate of the oxygen-enriched gas taken out from the storage tank, and an oxygen-enriched gas taken out from the storage tank according to the flow rate set in the flow rate setting means A flow rate control means for controlling the flow rate is provided (for example, Patent Document 1). By changing the flow rate set in the flow rate setting means, the patient can adjust the flow rate of the oxygen enriched gas to be extracted to a value according to the doctor's prescription.

  However, in the conventional medical oxygen concentrator using this pressure fluctuation adsorption separation method, the flow rate control means is a partition plate provided with a plurality of orifices having different diameters. The flow rate of the oxygen-enriched gas is controlled by switching the orifice through which the concentrated gas passes. For this reason, it has been difficult to control the flow rate of the oxygen-enriched gas with high accuracy. In addition, it has been difficult to improve the function of the oxygen-enriched gas supply device, such as adjusting the flow rate of the oxygen-enriched gas according to the breathing state of the user. Furthermore, a pressure reducing valve (flow control valve) is used to prevent the pressure of the oxygen-enriched gas from rising significantly due to breakage of the tube connected to the medical oxygen concentrator or the cannula connected to the tube. Etc. had to be provided separately. In addition, the temperature characteristics of this pressure reducing valve are highly dependent, and it has been necessary to readjust periodically (for example, at the turn of the season). This requires a high degree of precision for the pressure reducing valve, and the price is relatively high. It was.

  By the way, in Patent Document 2, a pressure measuring means is connected to a gas flow path connecting the oxygen concentrating means and the flow rate control means, and pressure control for controlling the pressure upstream of the flow rate control means based on information from the pressure measurement means. A medical oxygen concentrator using a pressure fluctuation adsorption separation method provided with a means is described. Accordingly, it is possible to adjust the pressure of the oxygen-enriched gas without using a mechanical pressure regulating valve, and the entire apparatus can be reduced in size and weight. However, in this medical oxygen concentrator, as can be seen from the fact that the pressure control means performs a moving average process on the measured pressure of the oxygen-enriched gas (see [0029]), the pressure of the oxygen-enriched gas is not necessarily limited. It was not intended to prevent sudden abnormalities. Therefore, in order to prevent a sudden abnormality in the pressure of the oxygen-enriched gas in this medical oxygen concentrator, it is necessary to separately provide a pressure reducing valve or the like.

JP 2005-058469 A Japanese Patent Laid-Open No. 2005-066073

  The present invention has been made to solve the above problems, and provides an oxygen-enriched gas supply device capable of controlling the flow rate of oxygen-enriched gas with high accuracy. In addition, a safe oxygen enrichment that can prevent a sudden increase in the pressure of the oxygen enriched gas to be supplied without separately providing a pressure reducing valve in the gas flow path connected to the downstream side of the oxygen enriched gas supply source. It is also an object of the present invention to provide a gas supply device. Furthermore, it is an object of the present invention to provide an oxygen-enriched gas supply device that can be easily enhanced in function and can perform complicated operations in accordance with applications and purposes.

The above issues
An oxygen-enriched gas supply source for supplying oxygen-enriched gas;
A flow rate setting means for setting the flow rate of the oxygen-enriched gas taken out from the oxygen-enriched gas supply source;
A proportional control valve for controlling the flow rate of the oxygen-enriched gas taken from the oxygen-enriched gas supply source;
Pressure detecting means for detecting the pressure of the oxygen-enriched gas taken out from the oxygen-enriched gas supply source;
A flow rate detecting means for detecting the flow rate of the oxygen-enriched gas taken out from the oxygen-enriched gas supply source;
And a valve opening control means for controlling the valve opening of the proportional control valve in accordance with the flow rate F _DET detected by the pressure P _DET and the flow detecting means is detected by the pressure detecting means,
When the pressure P _DET is lower than the first upper limit pressure P _MAX1 , the valve opening of the proportional control valve is controlled so that the flow rate F _DET approaches the flow rate F _SET set by the flow rate setting means,
When the pressure P _DET is higher than the first upper limit pressure P _MAX1 , the problem is solved by providing an oxygen-enriched gas supply device characterized in that a shut-off operation for completely closing the proportional control valve is performed.

  Since the proportional control valve can control the valve opening steplessly from the fully open state to the fully closed state, the flow rate of the oxygen-enriched gas to be taken out is controlled with high accuracy by adopting the above configuration. It is possible to provide an oxygen-enriched gas supply device that can perform this. It is also possible to provide a safe oxygen-enriched gas supply device that can prevent a sudden increase in the pressure of the oxygen-enriched gas to be supplied without separately providing a pressure reducing valve. Further, since the proportional control valve can perform a complicated operation, the oxygen-enriched gas supply device can be further enhanced as will be described later.

In the oxygen-enriched gas supply device of the present invention, the control of the valve opening degree of the proportional control valve when the pressure P _DET is lower than the first upper limit pressure P _MAX1 is preferably performed by PWM control and / or PID control. Thereby, it becomes possible to draw out the performance of the proportional control valve and control the flow rate of the oxygen-enriched gas taken out from the storage tank with higher accuracy. Here, PWM control (pulse width modulation control) refers to the valve opening degree of the proportional control valve by changing the duty ratio of the pulse signal input to the proportional control valve or the duty ratio of the voltage supplied to the proportional control valve. It means to control. In addition, PID control (proportional plus integral plus derivative control) is an operation amount (valve opening of the proportional control valve) that is proportional to the difference between the target value (flow rate F _SET ) and the current value (flow rate F _DET ). In proportional control that is updated sequentially, integral control that changes the manipulated variable when the residual deviation (a value that accumulates the difference between the target value and the current value over time) exceeds a predetermined value, and the target value and the current value This is a control in which a differential control that changes the operation amount when the difference changes rapidly is added.

  The oxygen-enriched gas supply source may be an oxygen-enriched gas, an oxygen cylinder in which liquid oxygen is stored, or the like, but is preferably one that generates oxygen-enriched gas from ambient air (raw air). This makes it possible to provide an oxygen-enriched gas supply device (oxygen-enriched device) that can generate oxygen-enriched gas from ambient air on the spot and supply it to the user. This type of oxygen-enriched gas supply device can be suitably used as a medical oxygen concentrator used for oxygen inhalation therapy. In this case, the oxygen-enriched gas is usually supplied to the user (patient) via a cannula or a nasal mask.

The control method of the proportional control valve when the pressure P _DET is lower than the first upper limit pressure P _MAX1 varies depending on the use of the oxygen-enriched gas supply device and is not particularly limited.
When the flow rate F _DET becomes smaller than the first lower limit flow rate F _MIN1 , the flow rate increasing operation for increasing the valve opening degree of the proportional control valve and bringing the flow rate F _DET closer to the flow rate F _SET ;
When the flow rate F _DET is _larger than the first upper limit flow rate F _MAX1 , the proportional control valve is opened by a continuous supply method that switches the flow rate F _DET to the flow rate F _SET by decreasing the valve opening of the proportional control valve. The degree is preferably controlled.
As a result, it becomes possible to prevent the flow of the oxygen-enriched gas taken out from the oxygen-enriched gas supply source from greatly _lowering the first lower limit flow F _MIN1 or greatly exceeding the first upper limit flow F _MAX1. The gas flow rate can be controlled with high accuracy. In this case, the PWM control or the PID control can be used in a flow rate increasing operation or a flow rate decreasing operation.

In addition, the oxygen-enriched gas supply device of the present invention includes a respiration detection means for detecting the breathing state of the user (whether the user is in the expiration phase or the inspiration phase),
When the pressure P _DET is lower than the first upper limit pressure P _MAX1 ,
Expiratory phase operation that substantially completely closes the proportional control valve when the respiratory state detected by the respiration detecting means becomes the expiratory phase;
Immediately after the breathing state detected by the breathing detection means becomes the inspiration phase, the flow rate of the oxygen-enriched gas exceeds the flow rate F _SET (usually 2 to 5 times the flow rate F _SET ). After the valve opening is increased, the valve opening of the proportional control valve is controlled by a respiration synchronized supply method that switches between the intake phase operation that operates the proportional control valve so that the average flow rate of the oxygen-enriched gas approaches the flow rate F _SET. It is also preferable to do so.
Accordingly, it becomes possible to supply the oxygen-enriched gas in synchronism with the timing when the user (patient) breathes, and wasteful consumption of the oxygen-enriched gas can be suppressed. In addition, when the respiratory state becomes the inspiratory phase, the flow rate of the oxygen-enriched gas temporarily exceeds the flow rate F _SET , so that the inhaled oxygen-enriched gas is reduced in consideration of the flow resistance of the gas flow path in the humidifying means. It is also possible to make it easier to reach the user's alveoli. These configurations are preferably employed when the oxygen-enriched gas supply device of the present invention is used as a medical oxygen concentrator.

In the oxygen-enriched gas supply device of the present invention, the control method of the proportional control valve in the case where the pressure P _DET is lower than the first upper limit pressure P _MAX1 may be uniquely determined in advance. It is preferable that a control method (for example, a continuous supply method, a respiration synchronization supply method, etc.) can be selected. Thereby, the user can select the control method of the proportional control valve according to the symptom or day and night.

More specifically, a valve control method setting means for selecting a control method of the proportional control valve when the pressure P _DET is lower than the first upper limit pressure P _MAX1 from at least a continuous supply method and a respiration synchronization supply method. When the breathing synchronized supply method is selected as the control method, the oxygen-enriched gas generation capability in the oxygen-enriched gas supply source is set lower than when the continuous supply method is selected. It is preferable. Thereby, it becomes possible to reduce the power consumption of an oxygen concentration gas supply apparatus. When oxygen-enriched gas is generated by the pressure fluctuation adsorption separation method, by changing the driving power of the compressor, which will be described later, lowering the switching pressure of the adsorption cylinder in which the adsorption process and the regeneration process are performed, etc. In addition, the ability to generate oxygen-enriched gas can be lowered.

  By the way, it is also preferable that the oxygen-enriched gas supply device of the present invention includes a humidifying unit for humidifying the oxygen-enriched gas taken out from the oxygen-enriched gas supply source. As a result, the oxygen-enriched gas can be supplied to the user after being humidified. This configuration can be suitably employed when the oxygen-enriched gas supply device of the present invention is used as a medical oxygen concentrator using a pressure fluctuation adsorption separation method. The oxygen-enriched gas produced by the pressure fluctuation adsorption separation method is very dry because not only nitrogen but also moisture is adsorbed by the adsorbent, and if this oxygen-enriched gas is sucked in as it is for a long time, This is because the user may hurt the mucous membrane of the mouth and nose.

As the humidifying means, a bubbling method in which water (semen-made water) is put in a container and oxygen-concentrated gas is passed through to be humidified is often used. When this type of humidifying means is used, Oxygen-concentrated gas may leak from that part due to forgetting to attach humidification means, forgetting to close the lid or container, or lack of tightening of the lid by weak elderly people when performing desorption work etc. . If the oxygen enriched gas leaks, the valve opening control means continues the flow increasing operation to bring the flow rate F _DET closer to the flow rate F _SET , even though the flow rate _FDET does not increase, until the proportional control valve is fully opened. There is also a possibility that the oxygen-enriched gas generation capacity in the gas supply source cannot catch up and the oxygen concentration of the oxygen-enriched gas is lowered. For this reason, it is preferable to devise the oxygen-enriched gas supply device of the present invention so that the abnormality of the humidifying means as described above can be detected. However, if an attempt is made to detect an abnormality of the humidifying means without being confused with a cannula breakage, it is necessary to monitor not only the pressure P _DET but also the flow rate F _DET . Therefore, when the flow rate F _DET is smaller than the second lower limit flow rate F _MIN2 (where F _MIN2 <F _MIN1 ), it is preferable to perform a humidifying means check operation for detecting the mounting state of the humidifying means. When the breathing synchronization method is selected as the control method of the proportional control valve, it is possible to prevent malfunction of the oxygen enriched gas supply device if the humidifying means check operation is not performed during the expiration phase operation. Can do. When the humidifying means check operation is performed, the humidifying means needs to be arranged upstream of the flow rate detecting means.

The humidifying means check operation is not particularly limited as long as it can detect the mounting state of the humidifying means, but is performed by intermittently opening and closing the proportional control valve, even though the proportional control valve is intermittently opened and closed. If the flow rate _FDET does not change, it is preferable to output a humidifying means attachment abnormality alarm. Thereby, without providing a photoelectric sensor or the like, it becomes possible to easily detect forgetting to attach the humidifying means or forgetting to close the lid and to notify the user of the abnormality.

Further, the oxygen-enriched gas supply device of the present invention includes blood oxygen saturation detection means for detecting the blood oxygen saturation of the user, and blood oxygen saturation detected by the blood oxygen saturation detection means When the degree is higher than the upper limit saturation or lower than the lower limit saturation, it is also preferable that the flow rate F _SET is corrected according to the degree. This makes it possible to change the flow rate of the oxygen-enriched gas to be supplied in real time according to the blood oxygen saturation level of the user. This configuration can be suitably employed when the oxygen-enriched gas supply device of the present invention is used as a medical oxygen concentrator. The upper limit saturation and the lower limit saturation are appropriately changed to values corresponding to the flow rate F _SET set in the flow rate setting means. When the flow rate F _SET is switched, the upper limit saturation and the lower limit saturation are also switched. It is supposed to be.

Furthermore, in the oxygen-enriched gas supply device of the present invention, the flow rate setting means may be of a knob type in which the flow rate of the oxygen-enriched gas taken out from the storage tank can be set by rotating the knob. It is preferable that the flow rate F _SET can be selected by operating a push button switch. Thereby, even if it is a person with a fingertip handicapped, it becomes possible to easily set the flow rate F _SET of the oxygen-enriched gas taken out from the storage tank.

  As described above, according to the present invention, it is possible to provide an oxygen-enriched gas supply device that can control the flow rate of the oxygen-enriched gas with high accuracy. In addition, a safe oxygen-enriched gas that can prevent a sudden increase in the pressure of the oxygen-enriched gas to be supplied without separately providing a pressure reducing valve in the flow path connected to the downstream side of the oxygen-enriched gas supply source It is also possible to provide a supply device. Furthermore, it is possible to provide an oxygen-enriched gas supply device that can be easily enhanced in function and can perform an efficient and complex operation according to the application and purpose.

1. Outline of Oxygen Concentrated Gas Supply Device A preferred embodiment of the oxygen concentrated gas supply device of the present invention will be described more specifically with reference to the drawings. FIG. 1 is a system flow diagram showing a preferred embodiment of the oxygen-enriched gas supply device of the present invention. FIG. 2 is a system flow diagram showing a preferred embodiment of the oxygen-enriched gas supply source 100 in the oxygen-enriched gas supply device of the present invention.

  As shown in FIG. 1, the oxygen-enriched gas supply apparatus according to the present embodiment includes an oxygen-enriched gas supply source 100 for supplying an oxygen-supply gas and a minute oxygen contained in the oxygen-enriched gas taken out from the oxygen-enriched gas supply source 100. A bacteria filter 200 for removing dust, a proportional control valve 201 for controlling the flow rate of the oxygen-enriched gas extracted from the oxygen-enriched gas supply source 100, and an oxygen-enriched gas extracted from the oxygen-enriched gas supply source 100. Oxygen concentration detection means 202 for detecting the oxygen concentration, pressure detection means 203 for detecting the pressure of the oxygen enriched gas taken out from the oxygen enriched gas supply source 100, and oxygen taken out from the oxygen enriched gas supply source 100 A check valve 205 for preventing the concentrated gas from flowing back, and the oxygen-enriched gas taken out from the oxygen-enriched gas supply source 100 Humidifying means 206 for humidifying, flow rate detecting means 204 for detecting the flow rate of the oxygen-enriched gas taken out from the oxygen-enriched gas supply source 100, respiration detecting means 207 for detecting the breathing state of the user, An oxygen-enriched gas outlet 208 for taking out the oxygen-enriched gas outside the apparatus is provided.

  Oxygen-enriched gas supply source 100, bacterial filter 200, proportional control valve 201, oxygen concentration detecting means 202, pressure detecting means 203, flow rate detecting means 204, check valve 205, humidifying means 206, respiration detecting means 207, oxygen concentrated gas collecting The arrangement of the outlets 208 is not limited to that shown in FIG. 1, and can be changed as appropriate without departing from the spirit of the present invention. For example, the breath detection means 207 may be disposed in a gas flow path between the check valve 205 and the humidification means 206, a gas tube (not shown) connected to the oxygen-enriched gas outlet 208, It may be arranged on a nasal mask or cannula connected to the tip of the gas tube. Further, in FIG. 1, the humidifying means 206 is arranged on the upstream side of the flow rate detecting means 204, but when the humidifying means check operation described later is not performed, the humidifying means 206 is located on the downstream side of the flow rate detecting means 204. May be arranged.

In addition to the above configuration, the oxygen-enriched gas supply device of this embodiment includes a flow rate setting means 209 for setting the flow rate of the oxygen-enriched gas taken out from the oxygen-enriched gas supply source 100, and the blood oxygen of the user A valve of the proportional control valve 201 according to the blood oxygen saturation detection means 210 for detecting the saturation, the pressure P _DET detected by the pressure detection means 203, the flow rate _FDET detected by the flow rate detection means 204, and the like. Valve opening degree control means 211 for controlling the opening degree is provided. The valve opening degree control means 211 is electrically connected to each of the proportional control valve 201, the pressure detection means 202, the flow rate detection means 204, the respiration detection means 207, the flow rate setting means 209, and the blood oxygen saturation detection means 210. Various data and various signals can be exchanged between them.

2. Oxygen-enriched gas supply source The oxygen-enriched gas supply source 100 may be an oxygen cylinder in which oxygen-enriched gas is stored in advance, a liquid oxygen cylinder in which liquid oxygen is stored, or the like, but from ambient air (source air) It is preferable that the oxygen-enriched gas can be generated. This makes it possible to obtain oxygen-enriched gas without storing oxygen-enriched gas or liquid oxygen in the oxygen-enriched gas supply source 100 in advance. Examples of the method for generating the oxygen-enriched gas include a pressure fluctuation adsorption separation method, a membrane separation method, an electrolysis method, and the like. The oxygen concentration gas supply source 100 of this embodiment uses a pressure fluctuation adsorption separation method. Thus, an oxygen-enriched gas having a high oxygen concentration can be efficiently generated.

  The oxygen-enriched gas supply source 100 will be described more specifically. As shown in FIG. 2, the oxygen-enriched gas supply source 100 transfers a raw material air intake 101 for taking in surrounding air (raw material air) and a raw material air taken in from the raw material air intake 101. The compressor 103, the adsorption cylinders 110 and 111 in which the adsorbent capable of selectively adsorbing nitrogen contained in the raw air, and the oxygen-enriched gas generated in the adsorption cylinders 110 and 111 are temporarily stored. Storage tank 117 and electromagnetic valves 106, 107, 108, 109 for switching the flow path connected to the raw material air introduction end side (lower end side) of the adsorption cylinders 110, 111. The oxygen enriched gas outlet end side (upper end side) of the adsorption cylinders 110 and 111 is connected to the storage tank 117 via check valves 115 and 116 for preventing the backflow of the oxygen enriched gas. The storage tank 117 is connected to pressure detection means 118 for detecting the pressure in the storage tank 117.

  In addition, a filter for removing dust and the like contained in the raw air is attached to the raw air intake 101, and a gas flow path connecting the raw air intake 101 and the compressor 103 is provided with a compressor 103. A silencing tank 102 is provided to prevent the pulsation noise of the raw material air that is generated from leaking from the raw material air inlet 101. Further, a gas flow path connecting the compressor 103 and the solenoid valves 106, 107, 108, 109 has a muffler tank 104 for reducing the pulsation noise of the raw material air transferred from the compressor 103 to the adsorption cylinders 110, 111. A pressure detection means 105 for detecting the pressure of the raw material air transferred to the adsorption cylinders 110 and 111 is provided.

  Furthermore, the oxygen enriched gas outlet end side (upper end side) of the adsorption cylinders 110 and 111 are connected to each other via a solenoid valve 112 and an orifice 113 arranged in series. Further, the oxygen enriched gas outlet end side (upper end side) of the adsorption cylinders 110 and 111 are also connected to each other via the orifice 114. The solenoid valve 112 and the orifice 113 are for performing pressure equalization in the upper portion of the adsorption cylinders 110 and 111, and the orifice 114 is for purging the adsorption cylinders 110 and 111. On the other hand, the raw material air introduction end side (lower end side) of the adsorption cylinders 110 and 111 is connected to the exhaust gas discharge port 120 via the electromagnetic valves 107 and 109 and the silencing tank 119, respectively. The exhaust gas outlet 120 is provided with a silencer for silencing.

  The oxygen-enriched gas supply source 100 feeds the raw material air taken from the raw material air intake port 101 to the adsorption cylinders 110 and 111 by the compressor 103, and raises the pressure of the adsorption cylinders 110 and 111, thereby being included in the raw material air. Nitrogen adsorbed in the adsorption cylinders 110 and 111, an adsorption process in which oxygen gas that is difficult to adsorb is taken out from the product outlet end of the adsorption cylinder, and the adsorption cylinders 110 and 111 when the adsorption process is completed. The oxygen-enriched gas is alternately switched between the regeneration step of exhausting the remaining gas from the exhaust gas outlet 120 and desorbing the nitrogen adsorbed on the adsorbent by lowering the pressure of the adsorption cylinders 110 and 111. Are generated continuously. The adsorption process and the regeneration process are performed by switching the open / close state of the electromagnetic valves 106, 107, 108, 109 and the electromagnetic valve 112, and are repeatedly performed alternately between the adsorption cylinder 110 and the adsorption cylinder 111. . In addition, detailed operations such as upper pressure equalization and purging are substantially the same as those of a general oxygen concentrator using the pressure fluctuation adsorption separation method, and thus description thereof is omitted.

3. Proportional control valve Proportional control valve 201 is an input port for introducing oxygen-enriched gas, an output port for deriving oxygen-enriched gas, and an in-valve gas for guiding oxygen-enriched gas from the input port to the output port It is equipped with a flow path, a valve body for closing the gas flow path in the valve, and an electromagnet that moves the valve body by electromagnetic force, and changes the magnitude of the current that flows to the solenoid that constitutes the electromagnet By changing the position of the valve body, the valve opening degree can be adjusted to a value proportional to the magnitude of the current. The magnitude of the current flowing through the solenoid can be controlled directly or indirectly based on the signal SIG ₁ generated by the valve opening control means 211. For the signal SIG ₁ , analog electric signals such as DC 0 to 20 mA, DC 4 to 20 mA, DC 0 to 5 V, DC 0 to 10 V, etc. are usually used. The proportional control valve 201 can adjust the valve opening steplessly from the fully open state to the pre-closed state, and steplessly control the flow rate of the oxygen-enriched gas passing therethrough. It is possible to do. In the medical oxygen concentrator using the pressure fluctuation adsorption separation method, when the flow rate of the oxygen-enriched gas is suddenly changed, the state of the raw material gas and the oxygen-enriched gas inside the adsorption cylinders 110 and 111 is disturbed. The oxygen concentration may decrease for several minutes to several tens of minutes, but the oxygen concentration of the oxygen-enriched gas can be reduced by slowly changing the flow rate of the oxygen-enriched gas with the proportional control valve 201. Can be prevented.

4). Pressure detection means The type of the pressure detection means 203 is not particularly limited, and varies depending on the application of the oxygen-enriched gas supply device. However, when the oxygen-enriched gas supply device is used as a medical oxygen concentrator, a diaphragm type pressure sensor using a diaphragm as a pressure-sensitive element is usually used. The diaphragm type pressure sensor is not only capable of reliably detecting an abnormality in the pressure of the oxygen-enriched gas, but is often small in size so that the oxygen-enriched gas supply device can be easily downsized.

As a diaphragm type pressure sensor,
(1) Strain gauge pressure that detects the deflection of the diaphragm to which pressure is applied by the change in the electrical resistance of the strain gauge provided on the surface of the diaphragm, and detects the pressure applied to the diaphragm by the electrical resistance at that time. Sensors,
(2) A change in capacitance between a pair of fixed electrodes arranged on both sides of the diaphragm or a change in capacitance between the fixed electrode arranged on the periphery of the diaphragm and the capacitance of the diaphragm to which the pressure is applied A capacitance type pressure sensor that detects the change and detects the pressure applied to the diaphragm by the capacitance at that time,
(3) The change in the rigidity of the diaphragm to which pressure is applied is detected by the change in the resonance frequency of the diaphragm or the change in the resonance frequency of the vibrator connected to the diaphragm, and the change is applied to the diaphragm by the resonance frequency at that time. Examples include a vibration type pressure sensor that detects pressure.

  The pressure detection means 203 is for detecting that the pressure of the oxygen-enriched gas has reached an abnormal value, and may not be able to detect a minute change in the pressure of the oxygen-enriched gas. In the oxygen-enriched gas supply device of this embodiment, the pressure of the silicon diaphragm type (one type of gauge type) that can obtain the required measurement accuracy, is easy to mass-produce, is inexpensive, and is easy to downsize and handle. A sensor is used as the pressure detection means 203.

5. Flow rate detection means The flow rate detection means 204 is not particularly limited as long as it can detect the flow rate of the oxygen-enriched gas taken out from the oxygen-enriched gas supply source 100. Thermal type, ultrasonic type, differential pressure type, vortex type, area From various flow sensors such as a formula, the flow rate sensor is appropriately selected in consideration of measurement accuracy, rangeability, nominal diameter of the gas flow path, presence / absence of external vibration, responsiveness, dimensions, price, and the like.

In particular, when using an oxygen enriched gas supply device as a medical oxygen concentrator,
(1) Thermal type that detects the flow rate of oxygen-enriched gas using the fact that the amount of heat lost per unit time of the heating element placed in the flow of oxygen-enriched gas is proportional to the flow rate (mass flow rate) of oxygen-enriched gas Flow sensor,
(2) The flow rate of the oxygen-enriched gas is detected by utilizing the fact that the time difference between the ultrasonic waves emitted to the oxygen-enriched gas flowing through the gas flow path reaching the receiver is proportional to the flow rate (volume flow rate) of the oxygen-enriched gas. An ultrasonic flow sensor can be suitably used as the flow rate detection means 204.

These flow sensors can not only measure the flow rate of the oxygen-enriched gas with high accuracy even when external vibrations due to a compressor or the like occur, but also have high rangeability, and the flow rate setting means 209 allows the flow rate of the oxygen-enriched gas F _SET. This is because the flow rate of the oxygen-enriched gas can be reliably measured even when the gas is switched significantly. Flow rate F _DET of the oxygen enriched gas is detected by the flow detecting means 204, as shown in FIG. 1, is inputted to the valve opening control means 211.

6). Breath detection means The type of the breath detection means 207 is not particularly limited as long as it can detect the breathing state of the user, and a pressure sensor that can detect a minute change in the pressure of the oxygen-enriched gas due to the breathing of the user. In addition, a humidity sensor that can detect a minute change in humidity due to the user's breathing, a sensor that can detect movement of the chest and abdomen due to the user's breathing, and the like are exemplified. In the oxygen-enriched gas supply device of this embodiment, a pressure sensor is used as the respiration detection means 207. In this case, for example, when the internal pressure of the oxygen-enriched gas supply cannula increases, it can be determined that the user is exhaling air (expiratory phase), and when the internal pressure decreases, the user Can be determined to be in a state (intake phase).

The type of pressure sensor used as the respiration detecting unit 207 is not particularly limited, but a diaphragm type pressure sensor using a diaphragm as a pressure sensitive element can be suitably used as in the pressure detecting unit 203. In the oxygen-enriched gas supply device of this embodiment, a silicon diaphragm type pressure sensor that can detect a minute change in the pressure of the oxygen-enriched gas due to a user's breathing with high accuracy is used as the respiration detecting means 109. Yes. The pressure of the oxygen-enriched gas detected by the respiration detector 207 is input to the valve opening degree controller 211 (signal SIG ₂ ) as shown in FIG.

7). Flow rate setting means The flow rate setting means 209 is for the user to appropriately adjust the flow rate of the oxygen enriched gas taken out from the oxygen enriched gas supply source 100 to a value based on the doctor's prescription. In the oxygen-enriched gas supply device of this embodiment, the flow rate setting means 209 can select the flow rate F _SET by operating a push button switch. Therefore, it is possible to set the flow rate of the oxygen-enriched gas extracted from the oxygen-enriched gas supply source 100 by simply pressing a button switch without turning the knob, and even a person with a fingertip can easily operate it. ing. In the oxygen enriched gas supply device of the present embodiment, the flow rate of the oxygen enriched gas taken out from the oxygen enriched gas supply source 100 is 0.25 L / min, 0.5 L / min, 0.75 L / min, 1.0 L / min, It can be set in 8 steps of 1.5 L / min, 2.0 L / min, 2.5 L / min, and 3.0 L / min. The flow rate F _SET set in the flow rate setting means 209 is input to the valve opening degree control means 211 as shown in FIG.

8). Blood Oxygen Saturation Detection Unit The blood oxygen saturation detection unit 210 is preferably employed when the oxygen-enriched gas supply device is used as a medical oxygen concentrator. The blood oxygen saturation detecting means 210 is not particularly limited as long as it can detect the blood oxygen saturation of the user, but a pulse oximeter is usually used. The pulse oximeter is composed of a light emitting means for irradiating a measurement site such as a finger or an earlobe with light of a different wavelength, a light receiving device for converting light transmitted through the measurement site into an electrical signal, and the amplitude of each light. The blood oxygen saturation calculating means for calculating the blood oxygen saturation from the ratio is provided. The pulse oximeter uses the difference in light absorption characteristics between oxygenated hemoglobin (HbO ₂ ) and reduced hemoglobin (Hb) as a measurement principle, and the blood oxygen saturation level of the user without damaging the measurement site. Can be detected in real time. The blood oxygen saturation level of the user detected by the blood oxygen saturation level detection means 210 is input to the valve opening degree control means 211 (signal SIG ₃ ) as shown in FIG.

When the user's blood oxygen saturation level is input, the valve opening degree control unit 211 indicates the measured blood oxygen saturation level with the standard blood oxygen level stored in the memory unit of the valve opening degree control unit 211. It is compared with the saturation (standard blood oxygen saturation corresponding to the flow rate F _SET set in the flow rate setting means 209). When the measured blood oxygen saturation is higher than the upper limit saturation, the flow rate F _SET set in the flow rate setting means 209 is subtracted, and the flow rate of the oxygen-enriched gas passing through the proportional control valve 201 is reduced. Be reduced. On the other hand, when the measured blood oxygen saturation is lower than the lower limit saturation, an addition process is performed on the flow rate F _SET set in the flow rate setting means 209 and the oxygen-enriched gas passing through the proportional control valve 201 is added. The flow rate is increased. As described above, the flow rate of the oxygen-enriched gas to be supplied can be changed in real time according to the blood oxygen saturation level of the user. The addition amount or the subtraction amount of the flow rate F _SET can be set by the user according to the doctor's prescription, for example, 0.3 L / min every time the blood oxygen saturation changes by 1%.

  In addition, the blood oxygen saturation is not input from the blood oxygen saturation detection unit 210 to the valve opening degree control unit 211 for a predetermined time or more, or the blood oxygen saturation detection unit 210 performs the blood oxygen saturation detection. Is not measured normally, the valve opening degree control means 211 automatically returns the valve opening degree of the proportional control valve 201 to the state before the correction is made.

9. Valve Opening Control Unit The valve opening control unit 211 is proportional to an input unit for inputting an external signal such as the pressure P _DET detected by the pressure detection unit 203 and the flow rate F _DET detected by the flow rate detection unit 204. An output unit for outputting a signal SIG ₁ for controlling the valve opening degree of the control valve 201 to the proportional control valve 201, a first upper limit pressure P _MAX1 , a first upper limit flow rate F _MAX1 , a first lower limit flow rate F _MIN1, and a second A memory unit for storing parameters such as the lower limit flow rate F _MIN2 and a program for generating the signal SIG ₁ based on these parameters, and a central processing unit (CPU) for executing the program are provided. ing. In the oxygen-enriched gas supply device of this embodiment, a small programmable controller is used as the valve opening degree control means 211.

Among the parameters stored in the memory section of the valve opening control means 211, the first upper limit pressure P _MAX1 determines that the pressure of the oxygen-enriched gas taken out from the oxygen-enriched gas supply source 100 is in a normal range. It is an upper limit threshold for When the pressure P _DET detected by the pressure detection means 203 exceeds the first upper limit pressure P _MAX1 , it can be determined that a problem such as a broken tube connected to the oxygen enriched gas outlet 208 has occurred. The first upper limit pressure P _MAX1 may be appropriately changed according to the value of the flow rate F _SET set in the flow rate setting means 209, but is usually a constant. The specific value of the first upper limit pressure P _MAX1 varies depending on the application of the oxygen-enriched gas supply device and is not particularly limited. When the oxygen-enriched gas supply device is used as a medical oxygen concentrator, a value of about 20 to 50 kPa is normally set as the first upper limit pressure P _MAX1 . In the oxygen-enriched gas supply device of this embodiment, the first upper limit pressure P _MAX1 is set to 35 kPa.

Of the parameters stored in the memory section of the valve opening control means 211, the first upper limit flow rate F _MAX1 is such that the flow rate of the oxygen-enriched gas taken out from the oxygen-enriched gas supply source 100 is in a suitable range. This is the upper limit threshold for determining The first upper flow _{F MAX1} is usually the flow rates _{F SET} switches set to the flow rate setting means 209, and is automatically changed to a value corresponding to the flow rate _{F SET.} The specific value of the first upper limit flow rate F _MAX1 varies depending on the application of the oxygen-enriched gas supply device and is not particularly limited. When using oxygen enriched gas supply device as a medical oxygen concentrator typically flow _{F DET} 0-20% increase is (1 to 1.2 times) the value is set as the first upper limit flow rate _{F MAX1} . In the oxygen-enriched gas supply device of this embodiment, a value obtained by increasing the flow rate F _SET set in the flow rate setting unit 209 by 10% (1.1 times) is automatically set as the first upper limit flow rate F _MAX1. It has become.

Further, among the parameters stored in the memory section of the valve opening control means 211, the first lower limit flow rate _FMIN1 is such that the flow rate of the oxygen-enriched gas taken out from the oxygen-enriched gas supply source 100 is in a suitable range. This is the lower limit threshold for determining The first lower flow rate _{F MIN1} is usually the flow rates _{F SET} switches set to the flow rate setting means 209, and is automatically changed to a value corresponding to the flow rate _{F SET.} The specific value of the first lower limit flow rate F _MIN1 varies depending on the application of the oxygen-enriched gas supply device and is not particularly limited. When using oxygen enriched gas supply device as a medical oxygen concentrator is usually value flow _{F DET} 0-20% decrease (0.8-fold) the is set as a first lower limit flow rate _{F MIN1} . In the oxygen-enriched gas supply device of this embodiment, a value obtained by reducing the flow rate F _SET set in the flow rate setting unit 209 by 10% (0.9 times) is automatically set as the first lower limit flow rate F _MIN1. It has become.

Furthermore, among the parameters stored in the memory section of the valve opening control means 211, the second lower limit flow rate F _MIN2 indicates that the humidifying means 206 is normally attached to the main body of the oxygen-enriched gas supply device. This is the lower limit threshold for determination. The second lower limit flow rate F _MIN2 may be appropriately changed according to the value of the flow rate F _SET set in the flow rate setting means 209, but is usually a constant. The specific value of the second lower limit flow rate F _MIN2 differs depending on the application of the oxygen-enriched gas supply device and is not particularly limited. When the oxygen-enriched gas supply device is used as a medical oxygen-concentrating device, normally, the value of 0 L / min or about half or less of the flow rate F _SET set in the flow rate setting means 209 is set as the second lower limit flow rate F _Min2. It has come to be.

10. Humidification means Since the oxygen-enriched gas produced using the pressure fluctuation adsorption separation method is very dry, if it is inhaled as it is for a long time, the user's mouth and nasal mucosa may be damaged. For this reason, in the oxygen-enriched gas supply device of this embodiment, the humidifying means 206 is provided between the oxygen-enriched gas supply source 100 and the oxygen-enriched gas outlet 208. The humidifying means 206 can be removed from the main body of the oxygen-enriched gas supply device, and maintenance such as replenishment of moisture and cleaning can be easily performed.

11. Operation of Oxygen Concentrated Gas Supply Device Next, the operation of the oxygen concentrated gas supply device of this embodiment will be described. The oxygen-enriched gas supply device of this embodiment is a proportional control valve when the pressure P _DET detected by the pressure detection means 203 is lower than the first upper limit pressure P _MAX1 stored in the memory section of the valve opening degree control means 211. The control method 201 can be selected from a continuous supply method and a respiration synchronization supply method by a valve control method setting means (not shown).

  First, the operation when the continuous supply method is selected as the control method of the proportional control valve 201 will be described. FIG. 3 is a graph showing conditions under which each of the shut-off operation, the flow rate decreasing operation, the flow rate increasing operation, and the humidifying means check operation is started when the continuous supply method is selected as the control method of the proportional control valve 201. It is. FIG. 4 is a flowchart showing a process performed by the valve opening degree control means 211 when the continuous supply method is selected as the control method of the proportional control valve 201.

In the continuous supply system, as shown in FIG. 3, when the pressure P _DET is higher than the first upper limit pressure P _MAX1 , a shut-off operation for completely closing the proportional control valve 201 is performed. Therefore, an abnormal increase in pressure in the gas flow path connected to the downstream side of the oxygen enriched gas supply source 100 is quickly detected, and the flow of the oxygen enriched gas from the oxygen enriched gas supply source 100 to the gas flow path Can be cut off. In this case, an alarm means or a display means (not shown) may be used to notify the user of an abnormality in the pressure of the oxygen-enriched gas (or that the flow path is blocked). The shut-off operation is continued until the pressure P _DET becomes lower than the first upper limit pressure P _MAX1 . When the shut-off operation is completed, the proportional control valve 201 is opened again, and normal operation is started.

On the other hand, when the pressure P _DET is lower than the first upper limit pressure P _MAX1 , when the flow rate F _DET becomes smaller than the first lower limit flow rate F _MIN1 , the valve opening degree of the proportional control valve 201 is increased and the flow rate F _DET is reduced. a flow rate increase operation closer to F _SET, the flow rate _{F DET} is first upper flow _F number becomes flow reduction operation and to switch the valve opening degree by reducing close the flow _{F DET} to the flow rate _{F SET} proportional control valve 201 than _MAX1 It is supposed to be. In the oxygen-enriched gas supply device of this embodiment, the flow rate increasing operation and the flow rate decreasing operation are performed by PWM control and / or PID control, and the flow rate of the oxygen concentrated gas taken out from the oxygen concentrated gas supply source 100 is adjusted. The flow rate F _SET set in the flow rate setting means 209 can be quickly approximated with high accuracy.

When the flow rate F _DET detected by the flow rate detection unit 204 falls below the second lower limit flow rate F _MIN2 , the valve opening degree control unit 211 starts the humidifying unit check operation as shown in FIG. Intermittent opening / closing (humidification means check operation) of the proportional control valve 201 is started to determine whether the humidification means 206 is normally attached to the main body of the oxygen-enriched gas supply device. In the oxygen concentrator of this embodiment, when an abnormality is detected in the mounting state of the humidifying means by the humidifying means check operation, a humidifying means wearing abnormality alarm is output, and the humidifying means is normally attached. The user can be notified of the absence. The humidifying means mounting abnormality alarm is output from an alarm means (not shown). The alarm means is not particularly limited as long as it can output a humidifying means attachment abnormality alarm, and examples thereof include those that emit light, those that emit sound, and those that emit vibration.

Next, an operation when the breathing synchronization supply method is selected as the control method of the proportional control valve 201 will be described. FIG. 5 is a flowchart showing the processing performed by the valve opening degree control means 211 when the breathing synchronization supply method is selected as the control method of the proportional control valve 201. In the breathing synchronized supply method, when the pressure P _DET is higher than the first upper limit pressure P _MAX1 , a shut-off operation for completely closing the proportional control valve 201 is performed as in the case of the continuous supply method.

On the other hand, when the pressure P _DET is lower than the first upper limit pressure P _MAX1 , when the user's breathing state detected by the breath detecting means 207 becomes the expiration phase, the expiration phase which closes the proportional control valve 201 substantially completely. After increasing the valve opening of the proportional control valve 201 so that the flow rate of the oxygen-enriched gas temporarily exceeds the flow rate F _SET when the operation and the breathing state of the user detected by the breath detection means 207 are in the inspiration phase, The intake phase operation for operating the proportional control valve 201 is switched so that the average flow rate of the oxygen-enriched gas approaches the flow rate F _SET . For this reason, the flow rate of the oxygen-enriched gas that the user substantially inhales can be matched with high accuracy by the flow rate F _SET set in the flow rate setting means 209. This operation can be realized by causing the valve opening degree control means 211 to perform the processing shown in the flowchart of FIG. 5, for example.

Even in respiratory tuning supply method, similar to the continuous supply method, when the flow rate F _DET detected by the flow rate sensing means 204 is below a second lower flow rate F _MIN2 is adapted humidifying means checking operation is performed .

11. Applications of oxygen-enriched gas supply device The oxygen-enriched gas supply device of the present invention can be used for various applications that require oxygen-enriched gas. Especially, it can incorporate suitably in the oxygen concentration apparatus which produces | generates and supplies oxygen concentrated gas from ambient air (raw material air). In particular, it can be suitably incorporated into a medical oxygen concentrator for performing oxygen inhalation therapy. It can also be used as an animal oxygen concentrator for inhaling oxygen-enriched gas into animals such as pets, and as a health oxygen concentrator for replenishing oxygen and exercising after exercise.

It is the system flow figure which showed the suitable embodiment of the oxygen concentration gas supply apparatus of this invention. It is a system flow figure showing a suitable embodiment of oxygen concentration gas supply source 100 in an oxygen concentration gas supply device of the present invention. It is the figure which showed the conditions where each of interruption | blocking operation, flow volume decreasing operation, flow volume increasing operation, and humidification means check operation is started when the continuous supply system is selected as the control system of the proportional control valve. It is the figure which showed the process which a valve opening degree control means performs when the continuous supply system is selected as the control system of a proportional control valve in the flowchart. It is the figure which showed to the flowchart the process which a valve opening degree control means performs, when the breathing synchronization supply system is selected as the control system of the proportional control valve.

Explanation of symbols

100 Oxygen-enriched gas supply source 101 Filter (raw material air inlet)
102 Silencer tank 103 Compressor (gas transfer means)
DESCRIPTION OF SYMBOLS 104 Silencer tank 105 Pressure detection means 106 Adsorption process-Regeneration process switching solenoid valve 107 Adsorption process-Regeneration process switching solenoid valve 108 Adsorption process-Regeneration process switching solenoid valve 109 Adsorption process-Regeneration process switching solenoid Valve 110 Adsorption cylinder 111 Adsorption cylinder 112 Solenoid valve for upper pressure equalization 113 Orifice for equalization of upper pressure 114 Orifice for purge 115 Check valve 116 Check valve 117 Storage tank 118 Pressure detecting means 119 Silencer tank 120 Silencer (exhaust gas exhaust port) )
DESCRIPTION OF SYMBOLS 200 Bacteria filter 201 Proportional control valve 202 Oxygen concentration detection means 203 Pressure detection means 204 Flow rate detection means 205 Check valve 206 Humidification means 207 Respiration detection means 208 Oxygen concentrated gas outlet 209 Flow rate setting means 210 Blood oxygen saturation detection means 211 Valve opening control means F Flow detected by _DET flow detection means F _MIN1 first lower limit flow F _MAX1 first upper limit flow P Pressure detected by _DET pressure detection means P _MAX1 first upper limit pressure SIG ₁ signal SIG ₂ signal SIG ₃ signals

Claims (10)

An oxygen-enriched gas supply source for supplying oxygen-enriched gas;
A flow rate setting means for setting the flow rate of the oxygen-enriched gas taken out from the oxygen-enriched gas supply source;
A proportional control valve for controlling the flow rate of the oxygen-enriched gas taken from the oxygen-enriched gas supply source;
Pressure detecting means for detecting the pressure of the oxygen-enriched gas taken out from the oxygen-enriched gas supply source;
A flow rate detecting means for detecting the flow rate of the oxygen-enriched gas taken out from the oxygen-enriched gas supply source;
And a valve opening control means for controlling the valve opening of the proportional control valve in accordance with the flow rate F _DET detected by the pressure P _DET and the flow detecting means is detected by the pressure detecting means,
When the pressure P _DET is lower than the first upper limit pressure P _MAX1 , the valve opening of the proportional control valve is controlled so that the flow rate F _DET approaches the flow rate F _SET set by the flow rate setting means,
When the pressure P _DET is higher than the first upper limit pressure P _MAX1 , a shut-off operation for completely closing the proportional control valve is performed. The oxygen-enriched gas supply device according to claim 1, wherein control of the valve opening degree of the proportional control valve when the pressure P _DET is lower than the first upper limit pressure P _MAX1 is performed by PWM control and / or PID control. When the pressure P _DET is lower than the first upper limit pressure P _MAX1 ,
When the flow rate F _DET becomes smaller than the first lower limit flow rate F _MIN1 , the flow rate increasing operation for increasing the valve opening degree of the proportional control valve and bringing the flow rate F _DET closer to the flow rate F _SET ;
When the flow rate F _DET is _larger than the first upper limit flow rate F _MAX1 , the proportional control valve is opened by a continuous supply method that switches the flow rate F _DET to the flow rate F _SET by decreasing the valve opening of the proportional control valve. The oxygen-enriched gas supply device according to claim 1 or 2, wherein the degree is controlled. Equipped with a breath detection means for detecting the breathing state of the user,
When the pressure P _DET is lower than the first upper limit pressure P _MAX1 ,
Expiratory phase operation that substantially completely closes the proportional control valve when the respiratory state detected by the respiration detecting means becomes the expiratory phase;
Immediately after the breathing state detected by the breathing detection means becomes the inspiratory phase, the valve opening of the proportional control valve is increased so that the flow rate of the oxygen-enriched gas exceeds the flow rate F _SET, and then the average flow rate of the oxygen-enriched gas becomes The oxygen-enriched gas supply device according to claim 1 or 2, wherein the valve opening degree of the proportional control valve is controlled by a breathing synchronized supply system that switches between an intake phase operation that operates the proportional control valve so as to approach the flow rate F _SET .   The oxygen-enriched gas supply device according to any one of claims 1 to 4, wherein the oxygen-enriched gas supply source generates oxygen-enriched gas from ambient air. A valve control method setting means for selecting a control method of the proportional control valve when the pressure P _DET is lower than the first upper limit pressure P _MAX1 from at least a continuous supply method and a respiration synchronized supply method;
The oxygen-enriched gas generation capability in the oxygen-enriched gas supply source is set lower when the breath-synchronized supply method is selected as the control method than when the continuous supply method is selected. Concentrated gas supply device. A humidifying means for humidifying the oxygen-enriched gas taken out from the oxygen-enriched gas supply source;
The humidifying means check operation for detecting the mounting state of the humidifying means is performed when the flow rate F _DET is smaller than the second lower limit flow rate F _MIN2 (where F _MIN2 <F _MIN1 ). The oxygen-enriched gas supply device described. The humidifying means check operation is performed by intermittently opening and closing the proportional control valve,
The oxygen-enriched gas supply device according to claim 7, wherein when the flow rate _FDET does not change even though the proportional control valve is intermittently opened and closed, a humidifying means wearing abnormality alarm is output. Equipped with blood oxygen saturation detection means for detecting the blood oxygen saturation of the user,
When the blood oxygen saturation detected by the blood oxygen saturation detecting means is higher than the upper limit saturation or lower than the lower limit saturation, the flow rate F _SET is corrected according to the degree. The oxygen-enriched gas supply device according to any one of 1 to 8. The oxygen-enriched gas supply device according to any one of claims 1 to 9, wherein the flow rate setting means can select a flow rate F _SET by operating a push button switch.

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