JP2776992B2 - Oxygen concentrator - Google Patents

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 obtaining oxygen-enriched gas from air, and more particularly to an oxygen concentrator suitable for medical use.

[0002]

2. Description of the Related Art Low-noise conditions are indispensable conditions for medical oxygen concentrators, which are used at home and hospitals near the bedside of patients even at night. Two types of oxygen concentrators have been developed, a membrane oxygen concentrator using a selective oxygen permeable membrane and an adsorption oxygen concentrator using an adsorbent that selectively adsorbs oxygen or nitrogen. In general, the level of noise generated by an adsorption-type oxygen concentrator using a compressor or the like tends to be higher than that of a membrane-type oxygen concentrator using a vacuum pump or the like, and noise countermeasures have been desired.

In general, as a measure for reducing noise, a method of sealing a noise source with a sound insulating wall, a method of preventing vibration of the noise source to reduce solid-borne noise, and a method of attaching a sound absorbing material to an inner wall surface to reduce the sound. Methods and the like are known.

However, the pressure fluctuation adsorption type oxygen concentrator has a large noise source such as a compressor, and the amount of cooling air required for cooling it together with the electric motor is relatively large. Because an open flow path is indispensable, and the noise of the compressed oxygen gas generated during the desorption process is generated, it is extremely important to achieve sufficient effects with the noise reduction measures usually used. It was difficult.

[0005] For example, it is difficult to completely seal a noise source, and it is necessary to increase the mass of the sound insulating wall in order to enhance the sound insulating performance of the sound insulating wall. The dimensions are undesirably increased. Also, if the sound coming out of the air inlet / outlet is larger than the sound passing through the wall, the noise level of the entire device will be limited by the sound coming out of the cooling air flow path, and the sound insulation effect will not be obtained. .

[0006] In addition, when a sound absorbing material is adhered to the inner wall of the air passage, if the cross-sectional area of the passage is excessively reduced and the flow resistance is excessively increased, the amount of flowing air decreases, resulting in insufficient cooling of the pump. Inconvenience may occur. For this reason, it has been very difficult for a pressure fluctuation adsorption type oxygen concentrator to take a sufficient noise countermeasure without increasing the dimensions while maintaining a predetermined oxygen concentrating performance.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to remedy the above-mentioned disadvantages of the prior art and to reduce the noise without increasing the size of the conventional oxygen concentrator and without reducing the function of the concentrator. An object of the present invention is to provide a pressure fluctuation adsorption type oxygen concentrator.

[0008]

The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, noise has been generated in the air suction side conduit means of the compressed air supply means such as a compressor in the pressure fluctuation adsorption type oxygen concentrator. It has been found that the provision of a specific function for preventing noise from leaking out of the conduit means is very effective in reducing the noise of the entire apparatus, and has reached the present invention.

That is, the present invention relates to a pressure fluctuation adsorption type oxygen concentrator comprising an adsorption bed and a compressed air supply means driven by the power of an electric motor for supplying compressed air to the adsorption bed. It is an object of the present invention to provide an oxygen concentrator characterized in that a backflow prevention means is provided in a suction side conduit means of a supply means.

In the oxygen concentrating device of the present invention, the adsorbent bed is one unit, the compressed air supply means is a compressor means, and the compressor means has a function of supplying compressed air to the adsorbent bed. It includes one that has both functions of discharging gas from the adsorption bed.

[0011] The present invention also provides a pressure fluctuation adsorption type oxygen concentrator comprising an adsorption bed and a compressed air supply means driven by the power of an electric motor for supplying compressed air to the adsorption bed. It is an object of the present invention to provide an oxygen concentrator characterized in that an opening is provided in a tube side portion around a distal end portion of a suction side conduit means of a supply means.

Further, the present invention provides a pressure fluctuation adsorption type oxygen concentrator comprising an adsorption bed and a compressed air supply means driven by the power of an electric motor for supplying compressed air to the adsorption bed. An oxygen concentrator characterized in that the suction side conduit means of the air supply means is provided with a backflow preventing means and the suction side conduit means is provided with a silencer means.

According to the present invention, the silencer means has an opening at a pipe side around the tip of the suction-side conduit means, or a filter is provided at the tip of the suction-side conduit means. Includes an oxygen concentrator provided.

Hereinafter, the present invention will be described in more detail with reference to the drawings as necessary. The oxygen concentrator of the present invention is of a pressure fluctuation adsorption type (hereinafter sometimes abbreviated as PSA type), and pressurizes an adsorbent bed filled with an adsorbent capable of selectively adsorbing oxygen or nitrogen. This is a device that obtains a gas with an increased oxygen concentration by supplying the supplied air to selectively adsorb specific components and then reducing the pressure of the adsorption bed to perform desorption. Such an oxygen concentrator generally includes an adsorbent bed, a compressed air supply means driven by an electric motor, a fan means for generating an air flow for cooling the electric motor and the compressed air supply means, and an adsorbent bed and a compressed air supply means. The main components are conduit means for allowing compressed air to flow into the adsorbent bed by connecting them, and automatic valve means provided for controlling pressure fluctuations in adsorption and desorption.

The number of the adsorbing beds may be one or two or more. However, in the case of a small-sized oxygen concentrator for medical use, the number is preferably two or less, and particularly preferably one.
A compressor is usually used as the compressed air supply means, but may be a blower type in some cases. Further, as the fan means, it is preferable to use still another fan means in addition to the fan usually attached to the compressor itself, since the compressor and the like can be surely cooled. Further, the automatic valve means is for controlling the adsorption / desorption cycle of the adsorption bed, and may be of the two-type, three-type or four-type. Such an automatic valve means is preferably a DC-excited solenoid valve, an AC-excited solenoid valve, an air-operated automatic valve, a pilot-operated solenoid valve, or the like. An actuated solenoid valve or the like is more preferable in terms of measures such as a slow movement of an iron core or the like, a long life, a small sound generated at the time of operation, and a reduction in noise. In particular, a DC-excited solenoid valve is practical.

A feature of the oxygen concentrating device of the present invention resides in that the air suction side conduit means of the compressed air supply means such as a compressor is provided with a specific function part for preventing noise generation or reducing noise.

As an example of the functional part, there is an embodiment in which the air suction side conduit means is provided with a backflow prevention means.
As a preferred specific example of such backflow prevention means, there is a check valve means. As another specific example, there is an automatic opening / closing valve means which is controlled in advance so as to close immediately before the backflow of air occurs in the air suction side conduit means so that the backflow does not occur.

As an example of such an oxygen concentrator according to the present invention,
For example, there is a single-column pressure as shown in FIG. That is, in FIG. 1, air pressurized by the compressor 3 is sent to the adsorption bed 1 to selectively adsorb nitrogen in the adsorption bed 1 so that the oxygen concentration becomes 9%.
Oxygen-enriched gas, which has been increased to about 0%, is stored in the cushion tank 2, pressure-reduced and adjusted by a pressure regulating valve 9, and bacteria are removed by a sterilization filter 10, and then adjusted to a predetermined flow rate by a flow setting device 11. Further, the oxygen-enriched gas humidified by the humidifier 12 is supplied to the patient via a conduit means or a nasal cannula (not shown for convenience). After completion of the adsorption step for a predetermined time, the solenoid valve 8 is closed, and at the same time, the flow paths of the solenoid valves 4 and 5 are switched to form a flow path as shown in FIG. The pressure in the adsorption bed 1 is reduced to perform the desorption operation for a predetermined time. In this manner, a series of these pressure fluctuation adsorption operations are repeatedly performed while controlling the solenoid valves 4, 5, and 8 by control means (not shown for convenience) such as a microcomputer.

In the oxygen concentrating apparatus as shown in FIG. 1, a poppet-type solenoid valve which is considered to have little trouble due to foreign matter entrapment and excellent durability is used as the electromagnetic switching valves 4 and 5. When the flow paths are switched so that the solenoid valves 4 and 5 switch from the adsorption step to the desorption step, the suction-side conduit means 7 and the high-pressure side, that is, the adsorption bed 1 are temporarily connected, and the air is discharged from the high-pressure side. A phenomenon occurs in which the gas flows backward toward the inhalation-side conduit means 7, and the temporary air reflux causes periodic peculiar noises, which may cause discomfort to the patient using the oxygen concentrator. all right.

According to the present invention, the countermeasures against the noise due to the backflow are provided in the air inlet side conduit means of the compressor, which is not originally expected to occur and the special noise countermeasures are not taken. It was done. In the example of FIG. 1, a check valve 6 is provided in the middle of the suction-side conduit means 7 as a special noise countermeasure.

It is preferable that the exhaust side conduit means 13 is provided with a silencer means as required. Further, a fan 14 is used to cool the compressor. A partition plate is provided in the flow path of the cooling air, and the compressor and the fan, which are noise sources, are stored in a box for silencing. It is desirable to take measures such as noise reduction.
The box for noise reduction is usually made of an iron plate with a thickness of about 1 mm and has a sound absorbing material inside.
It has been found that a sufficient noise reduction effect can be obtained even when the thickness of the iron plate is reduced to about 0.4 mm. Therefore, it is desirable to reduce the noise and the weight by using such a thin metal plate such as an iron plate.

In cases other than those shown in FIG. 1, the present invention can effectively function as a noise reduction measure in a case where a backflow phenomenon to the suction side conduit means of the compressor, which is not originally supposed to flow gas, occurs.

Since the backflow of gas to the suction-side conduit means of the compressor is of a temporary pulse type, it is effective for preventing the suction-side conduit means from generating noise due to pulsed flow. Special provision of such silencer means is also useful as a noise reduction measure.

As a specific example of the special silencer means, one or preferably a plurality of openings are provided on the side of the tube near the distal end at the distal end of the suction side conduit means, and more preferably the distal end is sealed. There is a measure to stop the flow of the pulsed gas as it is and to use it as an air inlet. For example, a combination of two or more openings at the distal end sealing and the tube side, or a combination of one or more openings at the distal end opening and the tube side can be given. It is preferable to provide a sound absorbing material for improving the absorption of energy when a pulsed gas flow is applied to the inside of the sealing portion at the tip.

As another specific example of the silencer means, there is a measure of installing a filter means at the tip of the suction-side conduit means. It is preferable that the filter means also has a function of removing foreign substances in the air to be taken in and extending the life of the solenoid valve and the compressor.

In the oxygen concentrating device of the present invention, such a special silencer means is provided in the suction side conduit means of the compressor together with the backflow preventing means as described above.
A preferred embodiment has a higher noise reduction effect.

[0027]

According to the present invention, in a pressure swing adsorption type oxygen concentrator using a compressed air supply means of a compressor, a low noise type oxygen condensing apparatus can be used even when a backflow of gas occurs in a suction side conduit means of the compressor. An excellent effect that the oxygen concentrator can provide can be obtained. In particular, when the backflow prevention means is provided, a great effect is exerted on noise reduction.

[Brief description of the drawings]

FIG. 1 is a schematic flowchart of a preferred embodiment of an oxygen concentrator according to the present invention.

Claims (4)

(57) [Claims] 1. A pressure swing adsorption type oxygen concentrator comprising an adsorption bed and a compressed air supply means driven by the power of an electric motor for supplying compressed air to the adsorption bed. An oxygen concentrator characterized in that the suction side conduit means is provided with a backflow prevention means. 2. The method according to claim 1, wherein the adsorbent bed is a unit, the compressed air supply means is a compressor means, and the compressor means has a function of supplying compressed air to the adsorbent bed and a function of discharging gas from the adsorbent bed. The oxygen concentrator according to claim 1, wherein the oxygen concentrator has both of the above functions. 3. A pressure fluctuation adsorption type oxygen concentrator comprising an adsorption bed and a compressed air supply means driven by the power of an electric motor for supplying compressed air to the adsorption bed. An oxygen concentrator characterized in that the suction-side conduit means is provided with backflow prevention means, and the suction-side conduit means is provided with a silencer means. 4. A method according to claim 1, wherein said silencer means has an opening at a pipe side around a tip end of said suction side conduit means.
5. The oxygen concentrator according to claim 4, wherein a filter is provided at a tip portion of said suction side conduit means.