JP2003275313A - Oxygen concentration device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an oxygen concentration device by which the leakage stage of oxygen-concentrated gas in a humidifier, etc., can surely be grasped. <P>SOLUTION: At a step 100, an electromagnetic valve is driven to temporarily cut off the channel of the oxygen-concentrated gas. At a step 110, in order to stabilize the state of the flow, etc., of the oxygen-concentrated gas, the device waits for a prescribed period (2 to 3 sec, e.g.). At a step 120, the pressure P of the oxygen-concentrated gas is detected by a pressure sensor. At a step 130, it is decided whether the pressure P of the detected oxygen-concentrated gas becomes lower than a prescribed discrimination value KP, that is whether leakage occurs on the side of the humidifier. When it is decided to be YES, the step is advanced to a step 140. Since it is decided that leakage occurs on the side of the humidifier, an abnormality notification lamp is lighted (or flickered) and sound or voice is outputted to inform that leakage exists, at the step 140. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oxygen concentrator for producing high concentration oxygen by adsorbing and removing nitrogen from air, for example, and humidifying the oxygen to supply it to a patient or the like. Is.

[0002]

2. Description of the Related Art Conventionally, a medical oxygen concentrator has been used for home oxygen therapy or the like as a device capable of supplying a high concentration of oxygen to a patient. In this type of oxygen concentrator, for example, air whose pressure has been increased by a compressor is sent to an adsorption column filled with a nitrogen adsorbent, and this adsorption column adsorbs and removes nitrogen from the air to remove oxygen-enriched gas (high It is known to produce a gas containing a concentration of oxygen).

When using this oxygen concentrator, the patient normally inhales oxygen using a nasal cannula, but since the oxygen generated from the oxygen concentrator is dry (because it is dry), As the patient's symptoms increase oxygen requirements, the nose may become dry and uncomfortable.

As a countermeasure against this, a method of attaching a humidifier to an oxygen concentrator and humidifying oxygen by the humidifier to supply it to a patient is generally adopted. That is, the purified water is put into the humidifier, the humidifier is detachably attached to the oxygen concentrator body, and oxygen is passed through the purified water in the humidifier to perform the humidification.

In the oxygen concentrator described above, the device for setting the flow rate of oxygen is usually a fixed type using an orifice, and the flow rate is set by switching the orifice with a rotary switch. Then, whether or not the set flow rate of oxygen is flowing is roughly judged by using a simple flow indicator using a float and looking at the flow indicator.

[0006]

However, there are many elderly patients as patients who use the oxygen concentrator,
In some cases, the lid of the humidifier was not tightened when the purified water was added to the humidifier. In this case, the conventional flow indicator cannot detect unless there is a considerable leak, and if the lid is not tightly closed, a small amount of oxygen leaks in the humidifier, and the oxygen supplied to the humidifier becomes oxygen. In some cases, it was not fully returned to the concentrator body side.

Even when the humidifier lid is tightly closed, a small amount of oxygen leaks when the packing on the humidifier lid is aged or when the packing is left out. There was a problem. As a result, although the flow rate is set by the switch according to the doctor's prescription, there may be a problem that the required flow rate is not actually supplied to the patient, which is not preferable.

The present invention has been made to solve the above-mentioned problems, and an object thereof is to provide an oxygen concentrator capable of reliably grasping a leak state of an oxygen concentrated gas in a humidifier or the like.

[0009]

Means for Solving the Problems and Effects of the Invention (1) The invention of claim 1 comprises an oxygen concentrator body for concentrating oxygen from the air to produce an oxygen concentrated gas, and the oxygen concentrator body. The present invention relates to an oxygen concentrator for humidifying the oxygen-concentrated gas by passing the oxygen-concentrated gas through water in the humidifier, and in the present invention, the oxygen concentrator in the humidifier attached to the oxygen concentrator body is concentrated. It is characterized in that a leak detecting means for detecting a gas leak is provided.

That is, according to the present invention, the leakage detecting means prevents the leakage of the oxygen-concentrated gas in the humidifier itself or the connecting portion between the humidifier and the oxygen concentrator body when the humidifier is attached to the oxygen concentrator body. Can be detected. Therefore, according to the present invention, even if the patient who uses the oxygen concentrator is an elderly person or the like, it is possible to reliably check the leakage of the oxygen concentrated gas due to poor airtightness of the humidifier (for example, in the lid or packing) or mounting abnormality. it can. Therefore, it is possible to reliably prevent a situation in which the oxygen-concentrated gas flows out of the humidifier to the outside and a situation in which the oxygen-concentrated gas is not supplied from the humidifier to the main body of the oxygen concentrator, which is more preferable than in the past.

(2) In the invention of claim 2, the leak detecting means is a pressure sensor for detecting the pressure of the oxygen-enriched gas. The present invention exemplifies the leak detection means. That is, when there is a leak of the oxygen-enriched gas, the pressure is abnormal (decreased) as compared with the case where there is no leak, so the leak can be detected by finding this pressure abnormality.

(3) The invention of claim 3 is characterized in that the leak detecting means is a flow rate sensor for detecting the flow rate of the oxygen-enriched gas. The present invention exemplifies the leak detection means. That is, when there is a leak of the oxygen-enriched gas, there is an abnormality (increase) in the flow rate as compared with the case where there is no leakage, so the leak can be detected by finding this abnormality in the flow rate.

(4) The invention according to claim 4 is characterized in that the leak detecting means is arranged downstream of a pressure regulator for regulating the pressure of the oxygen-enriched gas. The present invention exemplifies the position where the leak detection means is arranged. That is, the oxygen-enriched gas is adjusted to have a predetermined pressure by the pressure regulator, and therefore, on the downstream side of the pressure regulator,
For example, leaks can be detected from changes in pressure. Further, even when the change in the flow rate is detected, the leak can be detected by detecting the change in the flow rate on the downstream side of the pressure regulator.

(5) The invention of claim 5 is characterized in that a shutoff means for temporarily shutting off the flow path of the oxygen-enriched gas is provided on the downstream side of the humidifier. The present invention exemplifies the position where the blocking means is arranged. That is, by blocking the flow path of the oxygen-enriched gas on the downstream side of the humidifier, it is possible to detect whether or not a leak has occurred in the humidifier on the upstream side of the blocking means.

(6) The invention of claim 6 is characterized in that the blocking means is a means for blocking the flow path by using at least one of an electromagnetic valve, an actuator and a step motor. The present invention exemplifies the blocking means. For example, turning on this electromagnetic valve shuts off the flow path, and turning it off opens the flow path (and vice versa).

The actuator is a mechanism that receives a certain signal and acts on a certain object or moves an object. For example, the actuator can be operated to cut off the flow path or open the flow path. . Furthermore,
By operating the step motor, the flow path can be blocked or opened.

(7) In the invention of claim 7, the flow path is temporarily blocked by the blocking means, and at the time of blocking,
It is characterized in that the leakage of the oxygen-enriched gas is detected by the leakage detection means arranged on the upstream side of the blocking means. The present invention illustrates a procedure for leak detection.

That is, in the state where the flow path is blocked by the blocking means, the leak of the oxygen-enriched gas is detected by, for example, a pressure sensor or a flow rate sensor arranged upstream thereof,
Even a minute leak can be accurately detected without being affected by the normal oxygen breathing operation of the patient.

(8) The invention according to claim 8 is characterized in that the leak detection by the leak detecting means is performed when the power is turned on or when the humidifier is reattached while the oxygen concentrator is in operation. The present invention exemplifies the timing of leak detection.

In the present invention, when the power is turned on or the oxygen concentrator is in operation, for example, when purified water is added to the humidifier and the humidifier is reattached, the patient or the like then sucks the oxygen-concentrated gas. Therefore, the leakage is checked in advance before the suction operation is started.

That is, it is not preferable to suspend the supply of the oxygen-enriched gas during the actual suction, so that the leakage is checked in a short time before the actual suction is started. The safety is further improved. (9) According to the invention of claim 9, by the leak detecting means,
When a leak of the oxygen-enriched gas is detected, a notification means is provided to notify that effect.

In the present invention, when a leak in the humidifier is detected, for example, the fact that there is a leak is notified, and the patient or medical staff who has received the notification can respond appropriately according to the contents of the notification. it can. (10) The invention according to claim 10 is characterized in that the notifying means notifies by a display and / or a sound.

The present invention exemplifies the contents of notification by the notification means. The contents of this notification include the operation of the lamp (lighting, extinguishing, blinking), or the display of characters or pictures indicating a leak by a display device such as a display. Alternatively, a buzzer sound, an electronic sound, a melody, or a voice notification may be used. In particular, it is preferable to combine the notification with the display and the sound.

Examples of the oxygen concentrator include a device for adsorbing and removing nitrogen from the air by a nitrogen adsorbent filled in an adsorption column to concentrate oxygen, and a device using an oxygen selective permeable membrane.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an example (embodiment) of an embodiment of an oxygen concentrator of the present invention will be described with reference to the drawings. (Example 1) In this example, oxygen is concentrated by adsorbing and removing nitrogen from the air using a nitrogen adsorbent,
An example is a medical oxygen concentrator (hereinafter referred to as an oxygen concentrator) that humidifies the oxygen-concentrated gas containing a high concentration of oxygen with a humidifier and supplies it to a patient.

A) First, each configuration for realizing the function of the oxygen concentrator of this embodiment will be described. As shown in FIG. 1, the oxygen concentrator 1 includes an air inlet 5, a dust filter 7, an intake filter 9, an intake muffler 10, a compressor 11, a heat exchanger 13, a heat exchanger 13, in an air introduction path 3 from the upstream side. A pair of switching valves (three-way switching valve) 15 and a pair of adsorption cylinders 17 filled with a nitrogen adsorbent are provided. A sirocco fan 19 is arranged near the compressor 11 and the heat exchanger 13.

Of these, the nitrogen adsorbent preferentially adsorbs nitrogen in the air when pressurized, and releases the adsorbed nitrogen when the pressure is lowered to regenerate the nitrogen adsorbent, which is a zeolite-based nitrogen. It is an adsorbent. In addition, a silencer 23 that silences intermittent exhaust noise is provided in the exhaust passage 21 that exhausts nitrogen from the pair of adsorption cylinders 17.

Furthermore, the supply passage 27 for supplying the oxygen-enriched gas from the pair of adsorption cylinders 17 is constituted by a pressure equalizing valve 29, which is a two-way valve for adjusting the pressure between the adsorption cylinders 17 from the upstream side, and an oxygen concentration. A pair of check valves 3 for preventing backflow of gas
0, a product tank 31 for storing oxygen-enriched gas, a pressure regulator 33 for adjusting the pressure of the oxygen-enriched gas, an oxygen sensor 34 for detecting the oxygen concentration of the oxygen-enriched gas, a bacterial filter 35 for preventing passage of bacteria and the like, oxygen-enriched A flow rate setter 37 that is a rotary switch that sets the flow rate of gas, a pressure sensor 39 that detects the pressure of the oxygen-enriched gas, a humidifier 41 that humidifies the oxygen-enriched gas, a solenoid valve 43 that opens and closes the flow path of the oxygen-enriched gas, And an oxygen outlet 45 is provided.

Further, the oxygen concentrator 1 of this embodiment is provided with a steel box (metal case) 53 as shown by a dotted line in the figure as a structure for preventing noise,
As shown by the solid line in the figure, an outer case 55 that covers them is provided. Of these, the metal case 53 is formed by sticking the inside of a metal plate with a vibration absorbing rubber and a sound absorbing material, and includes an intake filter 9, an intake muffler 10, and a compressor 1.
1, heat exchanger 13, switching valve 15, sirocco fan 19,
It covers the silencer 23 and the like.

Further, as shown in the perspective view of FIG. 2, in the oxygen concentrator 1 of this embodiment, a front cover 63 is arranged on the front surface portion 61 thereof, and the front surface portion 61 has an air intake port 5, The humidifier 41, the operation panel 65, etc. are arranged.
On the operation panel 65, a flow rate setting knob 67 for operating the flow rate setting device 37, a set flow rate display 64 for displaying the set flow rate in characters such as numbers, a power switch 69, and a flow display showing the supply state of oxygen-enriched gas. Lamp 68, oxygen outlet 4
5, the humidifier 41 will be described in detail later.
Abnormality notification lamp 7 for reporting leakage of oxygen-enriched gas from the
0 is provided.

In the oxygen concentrator 1 of the present embodiment having the above-mentioned structure, compressed air is sent to the adsorption cylinder 17 by the compressor 11, and when a pressure of about 198 kPa is reached, the switching valve is switched to the other adsorption cylinder 17. It is switched by 15 and is electrically controlled so that the adsorbed nitrogen is discharged together with the reduced pressure.

Further, the adsorption cylinder 17 can extract only oxygen at the time of pressurization, and the product tank 31, the pressure regulator 33, the bacteria filter 35, and the flow rate setter 3 downstream thereof can be extracted.
The oxygen-concentrated gas is supplied to the oxygen outlet 45 through the humidifier 41, the humidifier 41, and the solenoid valve 43. By repeating this alternately, 90% or more of concentrated oxygen can be continuously obtained, and further, by accumulating it in the product tank 31, variation is reduced to ensure continuity.

The oxygen concentrator 1 of this embodiment is a device having a continuous base flow rate of 5 L / min, a weight of 33 kg, a power consumption of 220 W, and an operating noise of 30 dB or less (in an anechoic chamber). b) Next, the configuration of the humidifier 41 will be described in more detail.

As shown in FIG. 3, the humidifier 41 for humidifying the oxygen-enriched gas is a transparent plastic container 71 containing water, which is covered with a plastic cap 73. A rubber packing 74 is arranged between the cap 73 and the cap 73.

The cap 73 is provided with a cylindrical inlet portion 75 for supplying dry oxygen from the flow rate setting device 37 and a cylindrical outlet portion 77 for supplying oxygen from the humidifier 41 to the oxygen outlet 45. Has been. In addition, a plastic cylindrical pipe 79 is provided in the inlet portion 75 from below.
Is fitted in, and the tip end side of the pipe 79 is put in the water put in the container 71. Further, in the opening 81 at the tip of the pipe 79, the bubble filter 8
3 is installed.

As shown in FIGS. 4 and 5, the humidifier 39
Is attached to the humidifier mounting portion 85 having a concave shape provided on the front surface portion 61 of the oxygen concentrator body 2. That is, the humidifier 4
1 from the front side to the back side of the paper surface of FIG.
(From the right side to the left side), the inlet part 75 of the humidifier 41 is fitted into the connection port 87 connected to the flow rate setting device 37, and the outlet part 77 is fitted into the connection port 89 connected to the oxygen outlet 45. .

As a result, the flow rate setter 37 to the humidifier 4
A flow path reaching the oxygen outlet 45 via 1 is formed. In particular, in this embodiment, as will be described in detail later, when it is determined that the oxygen-enriched gas is leaking in the humidifier 41, the abnormality notifying lamp 70 is provided to notify the leak.
Lights up (or flashes).

Alternatively, by utilizing the fact that the set flow rate display 64 can display characters, the set flow rate display 64 is
It is also possible to display (or blink) the characters or symbols that indicate an abnormality. It should be noted that the abnormality notification lamp 70 may be turned on (or blinking) and the characters of the set flow rate display 64 may be displayed.

At the same time, when it is determined that the oxygen-enriched gas is leaking, a sound (buzzer sound or electronic sound) or voice means is used to notify the effect. It should be noted that the abnormality notification lamp 70 and the set flow rate indicator 64 may be informed by visual means or only by means of audio (including voice) appealing means, but both informing means should be used. Is preferred.

C) Next, a control process for informing an abnormality due to a leak in this embodiment will be described. This control process is performed by the humidifier 4 when the power is turned on or the oxygen concentrator 1 is in operation.
It is carried out when the 1 is reattached. The mounting of the humidifier 41 can be detected by a sensor, a switch, or the like (not shown).

First, the principle of this control processing will be described. Normally, the pressure of the oxygen-enriched gas supplied from the oxygen concentrator 1 is adjusted by the pressure adjuster 33, for example, 34.
It is maintained at a substantially constant set value SP such as 3 kPa.

Therefore, when there is no leakage of the oxygen-enriched gas in the humidifier 41, the solenoid valve 43 shuts off the flow path between the humidifier 41 and the oxygen outlet 45.
Thus, the pressure near the set value SP of the pressure is detected. However, when there is a leak of the oxygen-enriched gas in the humidifier 41, if the flow path between the humidifier 41 and the oxygen outlet 45 is shut off by the solenoid valve 43, the pressure is increased by the amount of the leak of the oxygen-enriched gas. Since it decreases, the pressure value P detected by the pressure sensor 39 becomes lower than the set value SP of the pressure.

Therefore, it is possible to detect the leakage state of the oxygen-enriched gas based on the pressure value P detected by the pressure sensor 39 at that time by shutting off the flow path by the electromagnetic valve 43. Next, the procedure of this control processing will be described.

As shown in the flowchart of FIG. 6, first, in step 100, the solenoid valve 43 is driven to temporarily shut off the flow path of the oxygen-enriched gas. Continued Step 11
At 0, in order to stabilize the state of the flow of the oxygen-enriched gas, etc., it stands by for a predetermined time (for example, 2 to 3 seconds).

In the following step 120, the pressure sensor 39
The pressure P of the oxygen enriched gas is detected by. In the following step 130, it is determined whether or not the detected pressure P of the oxygen-enriched gas is below a predetermined determination value KP, that is, whether or not a leak has occurred on the humidifier 41 side. If an affirmative judgment is made here, the routine proceeds to step 140, while if a negative judgment is made, this processing is once terminated.

At step 140, since it is determined that the humidifier 41 is in a leak state, the abnormality notification lamp 70 is turned on (or blinks) or the character display using the set flow rate indicator 64 is performed. At the same time, the sound or voice is output to notify that there is a leak, and the present process is once terminated.

D) Next, the effect of this embodiment having the above-mentioned structure will be described. In the present embodiment, when the power is turned on, the solenoid valve 43 is driven to shut off the flow path, the pressure P at that time is detected, and when the detected pressure P is lower than the determination value KP, the humidifier. It is determined that the leak at 41 has occurred. This makes it possible to reliably detect the leakage of the oxygen-enriched gas in the humidifier 41.

For example, when the cap 73 of the humidifier 43 is not securely tightened, the packing 74 is aged, or the humidifier 43 is not securely connected to the oxygen concentrator body, a minute leak may occur. Although it may occur, even such a minute leak can be reliably detected.

When a leak of the oxygen-enriched gas in the humidifier 41 is detected, the abnormality notification lamp 70 or the set flow rate indicator 64 is used to notify the surroundings by a display, and also a sound or voice is used to notify the person well. Therefore, it is extremely safe. That is, even if the patient who uses the oxygen concentrator 1 is an elderly person or the like and is worried about the reliable wearing of the humidifier 39, it is possible to reliably detect the leakage of the oxygen concentrated gas and notify the surroundings. .

Therefore, since the oxygen-enriched gas is not used in a leaked state, the required flow rate can be reliably supplied to the patient, which is extremely preferable for a patient in any state. . (Embodiment 2) Next, the oxygen concentrator of Embodiment 2 will be described, but the description of the same parts as those in Embodiment 1 will be omitted.

A) In this embodiment, instead of the pressure sensor,
At the same position, a flow rate sensor that detects the flow rate of the oxygen enriched gas (for example, using a heat wire heater) is arranged, and the leak of the oxygen enriched gas is detected using this flow rate sensor. First, the principle of this control processing will be described.

Normally, the flow rate of the oxygen-enriched gas supplied from the oxygen concentrator 1 is set by the flow rate setting device 37,
For example, it is maintained at a substantially constant set value SQ such as 5 L / min. Therefore, when there is no leakage of the oxygen-enriched gas in the humidifier 41, if the flow path between the humidifier 41 and the oxygen outlet 45 is shut off by the solenoid valve 43, the oxygen-enriched gas does not flow. No flow rate is detected by (not shown).

However, when there is a leak of oxygen-enriched gas in the humidifier 41, if the flow path between the humidifier 41 and the oxygen outlet 45 is shut off by the solenoid valve 43, there is a slight flow rate. The flow rate sensor detects the flow rate Q corresponding to the leakage amount. Therefore, the flow rate Q detected by the flow rate sensor at that time is blocked by the electromagnetic valve 43.
The state of leakage of the oxygen-enriched gas can be detected based on the above.

Next, the procedure of this control processing will be described. As shown in the flowchart of FIG. 7, first, in step 200, the solenoid valve 43 is driven to temporarily shut off the flow path of the oxygen-enriched gas. In the following step 210, a predetermined time (for example, 2 to 3 seconds) is waited in order to stabilize the state of the flow of the oxygen-enriched gas.

In the subsequent step 220, the flow rate sensor detects the flow rate Q of the oxygen-enriched gas. Continued Step 2
At 30, it is determined whether the detected flow rate Q of the oxygen-enriched gas exceeds a predetermined determination value KQ, that is, whether the humidifier 41 has a leak. If an affirmative judgment is made here, the routine proceeds to step 240, while if a negative judgment is made, this processing is once terminated.

At step 240, since it is judged that the humidifier 41 is leaking, the abnormality notification lamp 70 is turned on (or blinks) or the character display using the set flow rate indicator 64 is performed. At the same time, the sound or voice is output to notify that there is a leak, and the present process is once terminated.

D) Also in this embodiment, by using the flow rate sensor in place of the pressure sensor 39, it is possible to reliably detect the leakage of the oxygen-enriched gas in the humidifier 41 and notify it, which is extremely safe. It is expensive. Needless to say, the present invention is not limited to the above-mentioned embodiments, and can be carried out in various modes without departing from the scope of the present invention.

(1) For example, in each of the above-described embodiments, the flow path of the pipe is blocked by driving the solenoid valve when the power is turned on, but the flow path of the pipe may be blocked by using an actuator, a step motor or the like. The shutoff is not limited to the solenoid valve. (2) Further, as the timing for detecting the leakage of oxygen, it is possible to adopt the time when the humidifier is reattached while the oxygen concentrator is in operation, other than the time when the power is turned on. That is, when the oxygen concentrator is powered on and the oxygen concentrator is in operation, the humidifier is removed,
When it is then reattached, the leak detection as in each of the above-described embodiments can be performed.

(3) Further, for example, in each of the above-described embodiments, the humidifier provided in the oxygen concentrator has been described, but other than this, the present invention can be applied to a case where the humidifier is connected to an oxygen cylinder, for example.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a basic configuration of an oxygen concentrator according to a first embodiment.

FIG. 2 is a perspective view of the oxygen concentrator of the first embodiment.

FIG. 3 is an explanatory diagram showing a humidifier of the oxygen concentrator of the first embodiment.

FIG. 4 is an explanatory view of a mounting portion of the humidifier of the oxygen concentrator of the first embodiment as viewed from the front.

FIG. 5 is a cross-sectional view showing a mounting portion of the humidifier of the oxygen concentrator of the first embodiment in a cutaway manner.

FIG. 6 is a flowchart showing a control process of the oxygen concentrator of the first embodiment.

FIG. 7 is a flowchart showing a control process of the oxygen concentrator of the second embodiment.

[Explanation of symbols]

1 ... Oxygen concentrator 33 ... Pressure setting device 37 ... Flow rate setting device 39 ... Pressure sensor 41 ... Humidifier 43 ... Electromagnetic valve 61 ... Operation panel 70 ... Abnormality notification lamp 74 ... Packing 85 ... Humidifier mounting part

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4D012 CA05 CB16 CD07 CE02 CF02                       CF03 CF05 CG01 CH10                 4G042 BA15 BB02 BC04                 5C086 AA02 AA22 AA38 BA07 CA16                       CA30 CB20 CB40 DA08 FA01                       FA18

Claims (10)

[Claims] 1. An oxygen concentrator body for producing oxygen-concentrated gas by concentrating oxygen from the air is provided, and a humidifier is attached to the oxygen concentrator body, so that the oxygen-concentrated gas is converted into water in the humidifier. An oxygen concentrator that performs humidification by passing the oxygen concentrator, comprising: leak detecting means for detecting a leak of the oxygen-concentrated gas in a humidifier attached to the oxygen concentrator body. 2. The oxygen concentrator according to claim 1, wherein the leak detection means is a pressure sensor that detects the pressure of the oxygen-enriched gas. 3. The oxygen concentrator according to claim 1, wherein the leak detection means is a flow rate sensor that detects a flow rate of the oxygen enriched gas. 4. The oxygen concentrator according to claim 1, wherein the leak detection means is arranged downstream of a pressure regulator that regulates the pressure of the oxygen-enriched gas. 5. The oxygen concentration according to any one of claims 1 to 4, further comprising a shut-off means provided on the downstream side of the humidifier to temporarily shut off the flow path of the oxygen-enriched gas. vessel. 6. The oxygen concentrator according to claim 5, wherein the shut-off unit is a unit that shuts off the flow path by using at least one of an electromagnetic valve, an actuator, and a step motor. 7. The shutoff means according to claim 5 or 6 temporarily shuts off the flow path, and at the time of shutoff, the oxygen is detected by the leak detection means arranged upstream of the shutoff means. An oxygen concentrator, which detects a leak of concentrated gas. 8. The oxygen concentrator according to claim 7, wherein the leak detection by the leak detection means is performed when the power is turned on or when the humidifier is reattached while the oxygen concentrator is in operation. 9. The leak detection means, when the leak of the oxygen-enriched gas is detected, is provided with an informing means for informing that fact. Oxygen concentrator. 10. The oxygen concentrator according to claim 9, wherein the notifying unit notifies by a display and / or a sound.