JP2012183162A - Oxygen concentrator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress to decrease in performance of an adsorption type oxygen concentrator.SOLUTION: For a dehumidifier module 110, one end thereof is fitted to a discharging opening 109 for the compressed air of a compressor 101, and the other end thereof is fitted to a high concentration oxygen forming part provided with a nitrogen adsorption material. The dehumidifier module 110 is constituted by binding a follow fiber membrane into a tube-like shape. The dehumidifier module 110 is wound on the compressor 101. In addition, the dehumidifier module 110 is blown by a blower 111.

Description

  The present invention relates to an oxygen concentrator that introduces air and releases a high concentration of oxygen. In particular, the present invention relates to an oxygen concentrator that generates high-concentration oxygen from compressed air obtained by a compressor.

  Some oxygen concentrators are used in home oxygen therapy (HOT) in which patients with respiratory diseases inhale oxygen at home. This type of oxygen concentrator is described in Patent Document 1, for example.

  The oxygen concentrator compresses indoor air taken in through a filter and an intake tank by a compressor. The oxygen concentrator separates high-concentration oxygen from the compressed air by passing the compressed air through a sieve bed (adsorption tower), and further humidifies the high-concentration oxygen. The sieve bed is filled with an adsorbent (for example, zeolite) having a property of adsorbing nitrogen to pressurized air and desorbing nitrogen to decompressed air. The high-concentration oxygen after humidification is supplied into the patient body through a nasal cannula worn by the patient at the time of use.

JP 2006-263441 A

  By the way, in the adsorption-type oxygen concentrator, it is known that an adsorption material (for example, zeolite) for adsorbing nitrogen significantly reduces the adsorption performance by adsorbing moisture. Furthermore, since the portable oxygen concentrator is assumed to be used under high humidity, the deterioration of the adsorbent may be accelerated.

  The present invention has been made in consideration of the above points, and an object thereof is to suppress a decrease in the performance of the adsorption oxygen concentrator.

  One aspect of the oxygen concentrator of the present invention includes a compressor that obtains compressed air, a nitrogen adsorbent, and a high-concentration oxygen generator that produces high-concentration oxygen from the compressed air obtained by the compressor. A dehumidification module provided between the compressor and the high-concentration oxygen generator.

  According to the present invention, since the compressed air that has been dehumidified by the dehumidifying module is introduced into the high-concentration oxygen generator, the amount of moisture adsorbed on the nitrogen adsorbent is reduced, and performance deterioration can be reduced, and Alternatively, the high-concentration oxygen generator can be downsized.

The figure which shows schematic structure of the oxygen concentrator which concerns on one embodiment of this invention. The block diagram which shows schematic structure of the control system of the oxygen concentrator of embodiment Exploded perspective view showing the configuration of the air compression unit Exploded perspective view showing the configuration of the air compression unit The perspective view which shows the structure of an air compression part. Diagram showing how the flow sensor is attached to the bottom case Perspective view showing external configuration of flow sensor Cross section of flow sensor Block diagram for explanation of motor control

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[1] Overall Configuration of Oxygen Concentrator FIG. 1 is a diagram showing a schematic configuration of a piping system of an oxygen concentrator according to an embodiment of the present invention. The oxygen concentrator 1 illustrated in FIG. 1 is a PSA (Pressure Swing Adsorption) type oxygen concentrator including an air intake unit 10, an air compression unit 100, a PSA unit 30, an oxygen storage unit 40, and an oxygen supply unit 50.

  The air intake unit 10 is a part that takes outside air that is raw material air into the housing, and includes an intake filter 11, a hepa filter 12, and the like. The intake filter 11 removes airborne particles such as dust and dust from the raw air introduced through the air intake port 13 provided in the housing. The hepa filter 12 removes fine particles that have not been removed by the intake filter 11.

  The air compressor 100 has a compressor 101. The compressor 101 compresses the raw material air introduced through the air intake unit 10 to generate compressed air.

  It is desirable to dispose an expansion silencer (silencer) that exhibits a silencing effect on the operation sound of the compressor 101 upstream of the compressor 101 (downstream of the hepa filter 12).

  The PSA unit 30 functions as a high concentration oxygen generation unit. The PSA unit 30 separates nitrogen from the compressed air generated by the compressor 101 to generate high-concentration oxygen, and sends this to the oxygen storage unit 40. The PSA unit 30 includes a flow path switching unit 31, an exhaust silencer 32, sheave beds (adsorption towers) 33A and 33B, a purge orifice 34, a pressure equalizing valve 35, a check valve 36, and the like.

  The flow path switching unit 31 is configured by a manifold (manifold) including four switching valves SV1 to SV4, and alternately sends the compressed air generated by the compressor 101 to the sheave beds 33A and 33B, and the sheave bed 33A. , 33B are alternately opened to atmospheric pressure to discharge nitrogen-enriched air.

  Specifically, in the flow path switching unit 31, the switching valve SV1 is “open” and the switching valve SV2 is “closed”, whereby the flow path from the compressor 101 toward the sheave bed 33A is opened, The flow path from the sheave bed 33A toward the exhaust silencer 32 is closed. At the same time, in the flow path switching unit 31, the switching valve SV3 is “closed” and the switching valve SV4 is “open”, whereby the flow path from the compressor 101 to the sheave bed 33B is closed, while the sheave bed 33B. To the exhaust silencer 32 is opened. In this case, compressed air generated by the compressor 101 is sent to the sheave bed 33A, and nitrogen-enriched air is released from the sheave bed 33B and exhausted through the exhaust silencer 32.

  When the switching valves SV1 to SV4 are in the opposite state, the compressed air generated by the compressor 101 is sent to the sheave bed 33B, and nitrogen-enriched air is discharged from the sheave bed 33A and exhausted. The air is exhausted through the silencer 32. The open / close state of the switching valves SV1 to SV4 is switched at intervals of 10 seconds, for example.

  The exhaust silencer 32 is connected to an exhaust port (not shown) provided in the casing of the oxygen concentrator 1, and exhausts when the nitrogen-enriched air discharged from the sheave beds 33A and 33B is discharged to the outside of the casing. Mute the sound.

  The sheave beds 33A and 33B separate nitrogen from the compressed air sent via the flow path switching unit 31, and generate high-concentration oxygen. The sieve beds 33A and 33B are filled with an adsorbent such as zeolite having the property of adsorbing nitrogen faster than oxygen.

  When the flow path from the air compression unit 100 is opened by the flow path switching unit 31, the sieve beds 33 </ b> A and 33 </ b> B are in a pressurized state by being fed with compressed air. At this time, in the sieve beds 33A and 33B, nitrogen and moisture are adsorbed and only oxygen passes, so that high-concentration oxygen is generated (adsorption process).

  The concentration of the high-concentration oxygen generated in the sieve beds 33A and 33B is adjusted to, for example, about 90%. Further, since zeolite adsorbs not only nitrogen but also moisture, the high-concentration oxygen produced in the sieve beds 33A and 33B is extremely dry (for example, humidity 0.1 to 0.2%).

  On the other hand, when the flow path to the exhaust silencer 32 is opened by the flow path switching unit 31, the sheave beds 33 </ b> A and 33 </ b> B are released to atmospheric pressure and are in a reduced pressure state. At this time, nitrogen and moisture adsorbed on the zeolite are desorbed, nitrogen-enriched air is released from the sieve beds 33A and 33B, and exhausted through the exhaust silencer 32. Thereby, the adsorption capacity of the sheave beds 33A and 33B is regenerated (regeneration step).

  The sheave beds 33 </ b> A and 33 </ b> B are connected to the product tank 41 of the oxygen storage unit 40 via check valves 36 and 36. The check valves 36 and 36 prevent the high-concentration oxygen stored in the product tank 41 from flowing back to the sheave beds 33A and 33B.

  Further, the downstream side of the sheave beds 33A and 33B is connected by a pipe having a purge orifice 34. The high-concentration oxygen produced in one sheave bed 33A (or 33B) is sent to the oxygen reservoir 40 via the check valve 36 and the other sheave bed 33B (or 33A) via the purge orifice 34. Is sent out. A part of the generated high-concentration oxygen is sent to the other sheave bed 33B (or 33A), whereby the regeneration process of the sheave bed 33B (or 33A) is efficiently performed. The flow rate of high-concentration oxygen in each flow path is controlled by the orifice diameter of the purge orifice 34.

  Further, the downstream side of the sheave beds 33 </ b> A and 33 </ b> B is connected by a pipe having a pressure equalizing valve 35. When the sieve beds 33A and 33B in the regeneration process are switched to the adsorption process, if compressed air is allowed to flow in under reduced pressure (atmospheric pressure), the nitrogen adsorption efficiency is poor. Therefore, the pressure equalizing valve 35 is “opened” at the time of switching, and the pressures of the sheave beds 33A and 33B are averaged.

  The oxygen storage unit 40 is a part that temporarily stores the high concentration oxygen generated by the PSA unit 30. The oxygen storage unit 40 includes a product tank 41, a pressure adjustment unit (pressure regulator) 42, an oxygen sensor 43, a pressure sensor 44, and the like.

  The product tank 41 is a container for storing high-concentration oxygen produced in the sheave beds 33A and 33B. Since the high concentration oxygen delivered from the sheave beds 33A and 33B is once stored in the product tank 41, the concentration fluctuation and pressure fluctuation of the high concentration oxygen are suppressed. Concentrated oxygen can be supplied.

  The pressure adjusting unit 42 adjusts the pressure of the high concentration oxygen to a constant pressure suitable for use in order to control the flow rate of the high concentration oxygen to be supplied. The pressure of the high-concentration oxygen stored in the product tank 41 varies not a little as long as there is an inflow to the product tank 41 or an outflow from the product tank 41. In this case, accurate flow rate control becomes difficult, and accurate concentration measurement by the oxygen sensor 43 becomes difficult. Considering this, the high-concentration oxygen is adjusted to a constant pressure by the pressure adjusting unit 42.

  The oxygen sensor 43 detects the concentration of high-concentration oxygen delivered from the pressure adjustment unit 42 at a predetermined interval (for example, 20 minutes) or continuously. As the oxygen sensor 43, for example, a zirconia type sensor or an ultrasonic sensor is suitable. Since the accurate measurement becomes difficult if the pressure of the high-concentration oxygen to be measured fluctuates, generally, the oxygen sensor 43 is connected to the downstream of the pressure adjustment unit 42 via the flow restriction orifice 45.

  The pressure sensor 44 detects the pressure of high-concentration oxygen stored in the product tank 41. Based on the detection result by the pressure sensor 44, it can be confirmed whether the pressure of the high concentration oxygen stored in the product tank 41 is maintained in a normal range.

  The oxygen supply unit 50 is a part that discharges high-concentration oxygen delivered from the oxygen storage unit 40 from the oxygen outlet 55 in synchronization with the user's breathing. The oxygen supply unit 50 includes a bacterial filter 51, a tuning valve 52, a pressure sensor 53, and the like.

  The bacteria filter 51 collects and disinfects bacteria contained in the high concentration oxygen in order to supply clean high concentration oxygen to the user.

  The tuning valve 52 is composed of a three-way valve having ports P1 to P3, and switches the flow path to open according to the user's breathing and adjusts the opening degree of the flow path to supply high concentration to the user. Control the flow rate of oxygen. The bacterial filter 51 is connected to the port P1 of the tuning valve 52, the oxygen outlet 55 is connected to the port P2, and the pressure sensor 53 is connected to the port P3.

  For example, when the tuning valve 52 is opened, a flow path (first flow path) connecting the port P1 and the port P2 is opened, and high-concentration oxygen is released from the oxygen outlet 55. On the other hand, when the tuning valve 52 is closed, the flow path (second flow path) connecting the port P2 and the port P3 is opened, and the pressure fluctuation caused by the user's breathing can be detected by the pressure sensor 53.

  The pressure sensor 53 is a sensor for detecting a user's respiration. The pressure sensor 53 is connected to the port P3 of the tuning valve 52 and has a flow rate downstream of the tuning valve 52 (a flow path connecting the port P2 and the oxygen outlet 55). It is connected via a restriction orifice 54. Therefore, in a state where the tuning valve 52 is “closed” (a state where the second flow path is opened), it is possible to detect a pressure that changes as the user breathes, and the tuning valve 52 is “open”. In the state of "" (the state in which the first flow path is open), it is possible to detect the pressure that changes with the supply of oxygen.

  In the oxygen concentrator 1, the open / close state of the tuning valve 52 is controlled based on the detection result by the pressure sensor 53. Specifically, when the negative pressure is detected by the pressure sensor 53 in a state where the tuning valve 52 is “closed”, the tuning valve 52 is instantaneously opened and supply of high-concentration oxygen is started. Is done. Then, after a predetermined time has elapsed, the tuning valve 52 is “closed”, whereby a predetermined amount of high-concentration oxygen is released. The high-concentration oxygen released from the oxygen supply unit 50 is supplied to the user via a nasal cannula or an oxygen mask connected to the oxygen outlet 55.

  Since the high concentration oxygen is in an extremely dry state, a humidifying unit for humidifying the high concentration oxygen may be provided upstream of the oxygen outlet 55.

  FIG. 2 is a diagram showing a schematic configuration of a control system of the oxygen concentrator according to the present embodiment.

  As shown in FIG. 2, the control unit 60 includes a CPU (Central Processing Unit) 61, a RAM (Random Access Memory) 62, a ROM (Read Only Memory) 63, and the like. The CPU 61 reads a program corresponding to the processing content from the ROM 63 and develops it in the RAM 62, and controls the operation of each block of the oxygen concentrator 1 in cooperation with the developed program.

  Specifically, the control unit 60 receives detection signals from the oxygen sensor 43 of the oxygen storage unit 40, the pressure sensor 53 of the oxygen supply unit 50, the temperature sensor 71 installed inside the housing, and other various sensors. Entered. In addition, an operation signal for instructing a set flow rate is input to the control unit 60 when, for example, a user sets a supply flow rate in the operation unit 81 having operation buttons and the like.

  Based on these input signals, the control unit 60 controls the number of rotations of the drive motor of the compressor 101, and controls the open / close state and opening degree of the switching valves SV1 to SV4 and the tuning valve 52 of the flow path switching unit 31. Or By such control, high concentration oxygen is supplied from the oxygen concentrator 1 at a set flow rate.

  In addition, the control unit 60 performs control related to display on the display unit 82 including a liquid crystal display (LCD) and a light emitting diode (LED), and control related to audio output from the speaker 83. . The display unit 82 and the speaker 83 are used when notifying the user of various types of information.

  Although not shown in the drawings, the oxygen concentrator 1 is provided with an interface that can be connected to a communication network such as a wireless local area network (LAN) or Bluetooth (equal power) so that various data can be transmitted to and received from an external device. May be.

[2] Configuration of Air Compression Unit FIG. 3 is an exploded perspective view showing the configuration of the air compression unit 100. In the air compression unit 100, the compressor 101 is accommodated by a front case 102, a rear case 103, and a bottom case 104.

  The compressor 101 is attached to the cases 102, 103, 104 via bushes 105, 106 as cushioning materials. In this way, vibration from the compressor 101 to the cases 102, 103, 104 can be reduced.

  An air passage 107 for taking air into the compressor 101 is formed in the bottom case 104. The air passage 107 is a passage of air sucked into the compressor 101, and functions as a damper for buffering this air. Specifically, if the outside air is taken into the compressor 101 without providing the air passage 107, the compressor operation is disturbed due to the disturbance of the air sucked into the compressor 101 due to the external environment and the shape of the intake port. In addition, there is a risk of inhalation noise. On the other hand, by providing the air passage 107 and taking in air rectified by the air passage 107 into the compressor, an effect of stabilizing the operation of the compressor 101 and a silencing effect can be expected.

  A flow sensor 108 is provided in the air passage 107. The flow rate sensor 108 is connected to the intake port 112 (FIG. 4) of the compressor 101 and measures the flow rate of air taken into the compressor 101.

  A tube-shaped dehumidifying module 110 is attached to the compressed air outlet 109 of the compressor 101. One end of the dehumidifying module 110 is attached to the compressed air discharge port 109 of the compressor 101, and the other end is attached to the PSA unit 30.

  The dehumidifying module 110 has a configuration in which hollow fiber membranes are bundled using an epoxy resin. As a result, water vapor contained in the compressed air flowing into the dehumidifying module 110 permeates from the inside to the outside of the hollow fiber membrane, and as a result, dried compressed air is sent from the dehumidifying module 110 to the PSA unit 30. Thereby, the amount of moisture adsorbed by the adsorbent (for example, zeolite) provided in the sieve beds 33A and 33B can be reduced. As a result, the original performance of the sheave beds 33A and 33B that adsorbs nitrogen is maintained. That is, the performance degradation of the PSA unit 30 can be suppressed.

  A blower 111 is provided inside the cases 102, 103, and 104. The blower 111 is disposed so that the air blowing port faces the dehumidifying module 110. In practice, the dehumidifying module 110 is arranged to wind the compressor 101 (FIG. 5), so the blower 111 blows air toward the dehumidifying module 110 and the compressor 101. Thereby, the dehumidification effect in the dehumidification module 110 is accelerated | stimulated, and the cooling effect with respect to the dehumidification module and the compressor 101 can be acquired.

  Incidentally, in a conventional general oxygen concentrator, a cooling pipe is provided between the compressor 101 and the PSA unit 30, and the compressed air is cooled by blowing air to the cooling pipe with a blower. . On the other hand, in the oxygen concentrator of the present embodiment, the dehumidifying module 110 also cools the compressed air, so that a cooling pipe is unnecessary.

  As shown in FIG. 4, an intake port 112 is provided at the bottom of the compressor 101. The intake port 112 is connected to the air passage 107 and sucks the raw material air through the air passage 107.

  As shown in FIG. 5, the dehumidifying module 110 is wound around the compressor 101. By doing in this way, since the length of the dehumidification module 110 can be lengthened, the dehumidification effect can be improved. In addition, since the dehumidifying module 110 is in contact with the compressor 101, the cooling effect of the compressor 101 by the dehumidifying module 110 can also be obtained. The blower 111 is disposed such that the air blowing port faces the dehumidifying module 110 and the compressor 101.

  FIG. 6 shows how the flow sensor 108 is attached to the air passage 107. Air flows through the air passage 107 in the direction of the arrow. An outside air introduction port 113 that penetrates the thickness of the bottom case 104 is formed at one end of the air passage 107, and air is introduced into the air passage 107 from the outside air introduction port 113. At the other end position P1 of the air passage 107, an intake port 112 (FIG. 4) of the compressor is disposed. As shown in the drawing, the flow sensor 108 is attached to the air passage 107 in close contact with the air passage 107. Incidentally, the exhaust port of the flow sensor 108 may be directly connected to the intake port 112 of the compressor.

[3] Configuration of Flow Sensor FIG. 7 is a perspective view showing an external configuration of the flow sensor 108. FIG. 8 is a cross-sectional view of the flow sensor 108 cut in the flow path direction.

  The flow sensor 108 is attached in close contact with the air passage 107 of the bottom case 104 via the packing 121. The flow sensor 108 includes a flow dividing unit 122 and a sensoring unit 123. As shown in FIG. 8, the flow dividing section 122 includes an orifice 125 formed in the main pipeline 124 and a bypass pipeline 126 formed so as to bypass the orifice. Air is introduced into the sensing unit 123 via the bypass pipe 126.

  The sensing unit 123 detects a current difference between the resistance element, a flow path connected to the bypass pipe 126, a resistance element provided on the upstream side and the downstream side of the flow path, a power source that supplies current to the resistance element, and the resistance element. A bridge circuit. With this configuration, it is possible to obtain a sensing result that the flow rate increases as the current difference between the resistance elements increases. The configuration of the sensing unit is not limited to this. In short, it is sufficient that the flow rate can be detected.

  The flow sensor 108 described above is a so-called mass flow sensor. In the present embodiment, by using a mass flow sensor, it is possible to perform a highly accurate flow rate measurement while suppressing a decrease in the flow rate of the main pipeline 124 and saving space.

  Here, as shown in FIG. 9 showing the motor drive system of the compressor 101, the measured flow rate obtained by the flow rate sensor 108 is sent to the control unit 133 of the compressor 101. The number of rotations of the motor 131 is detected by the hall sensor 132. The detected number of rotations is sent to the control unit 133. The set flow rate from the main control unit 60 of the oxygen concentrator 1 and the measured flow rate from the flow sensor 108 are input to the control unit 133. The control unit 133 controls the rotation speed of the motor so that the measured flow rate becomes the set flow rate. Thereby, the flow rate of the compressor 101 can be controlled with high accuracy so as to match the set diversion.

[4] Effect According to the present embodiment, the dehumidifying module 110 is provided in the flow path of the compressed air between the compressor 101 and the PSA unit (high-concentration oxygen generating unit) 30. Dry compressed air dehumidified by module 110 is introduced. Thereby, the amount of moisture adsorbed on the adsorbent is reduced, and performance degradation can be reduced. Since the amount of moisture adsorbed on the adsorbent is reduced, the nitrogen adsorption performance by the adsorbent can be enhanced, and thereby the desired nitrogen adsorption performance can be obtained even if the adsorbent is reduced. This contributes to the miniaturization of the PSA unit 30 and thus contributes to the realization of a smaller portable oxygen concentrator.

  Further, since the dehumidifying module 110 is a hollow fiber membrane bundled in a tube shape, highly efficient dehumidification can be performed in a narrow space. Therefore, it becomes easier to realize a small portable oxygen concentrator.

  Further, since the dehumidifying module 110 is wound around the compressor 101, the dehumidifying effect of the dehumidifying module 110 can be enhanced, and the cooling effect of the compressor 101 can be obtained.

  Moreover, since the blower 111 which blows air to the dehumidifying module 110 is provided, the dehumidifying effect of the dehumidifying module 110 can be further enhanced.

  In the above-described embodiment, the example in which the dehumidification module 110 is wound around the compressor 101 is shown. However, the dehumidification module 110 may be wound around the compressor 101 more than once. As the amount of winding of the dehumidifying module 110 around the compressor 101 is increased, the dehumidifying performance by the dehumidifying module 110 and the cooling effect on the compressor 101 by the dehumidifying module 110 can be enhanced.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the above embodiment, and can be changed without departing from the gist thereof.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1 Oxygen concentrator 10 Air intake part 30 PSA part 40 Oxygen storage part 50 Oxygen supply part 60, 133 Control part 100 Air compression part 101 Compressor 102 Front case 103 Rear case 104 Bottom case 105, 106 Bush 107 Air path 108 Flow rate sensor 109 Compressed air discharge port 110 Dehumidification module 111 Blower 112 Inlet port 121 Packing 122 Dividing part 123 Sensing part 124 Main line 125 Orifice 126 Bypass line 131 Motor 132 Hall sensor

Claims (5)

A compressor to obtain compressed air;
A high-concentration oxygen generator that has a nitrogen adsorbent and generates high-concentration oxygen from the compressed air obtained by the compressor;
A dehumidification module provided between the compressor and the high-concentration oxygen generator,
An oxygen concentrator comprising: The dehumidifying module has hollow fiber membranes bundled in a tube shape,
The oxygen concentrator according to claim 1. The dehumidifying module is wound around the compressor,
The oxygen concentrator according to claim 2. Further comprising a blower for blowing air to the dehumidifying module;
The oxygen concentrator according to any one of claims 1 to 3. The compressor and the dehumidifying module are accommodated in the same case.
The oxygen concentrator according to any one of claims 1 to 4.

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