JP2002253676A - Adsorbing type oxygen concentrating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the starting performance under a low temperature environment such as the winter season of an adsorbing type oxygen concentrating device which is a medical treatment appliance being used at home for a long period of time. SOLUTION: This adsorbing type oxygen concentrating device is equipped with at least one adsorbing bed, a compressor means, a channel switching means, and an oxygen feeding means. In this case, an adsorbing agent which selectively adsorbs oxygen or nitrogen is filled in the adsorbing bed. The compressor means feeds compressed air to the adsorbing bed. The channel switching means switches an adsorption process and a desorption/reproduction process of the adsorbing bed. The oxygen feeding means feeds the oxygen concentrated gas which is obtained from the adsorbing bed to a user. In such an adsorbing type oxygen concentrating device, a control means which controls the secondary side pressure of the compressor means is provided. In this case, the control means is a means to suppress the increase in the secondary side pressure at the time of starting of the adsorbing type oxygen concentrating device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oxygen concentrating apparatus which uses an adsorbent for selectively adsorbing oxygen or nitrogen and condenses oxygen from air by a pressure fluctuation adsorption method and supplies the oxygen to a user. More specifically, the present invention relates to a pressure-variation adsorption-type oxygen concentrator with improved start-up performance by controlling a load applied when starting up a compressor means for supplying pressurized air to an adsorption bed.

[0002]

2. Description of the Related Art In recent years, the number of patients suffering from respiratory diseases such as asthma, emphysema and chronic bronchitis tends to increase. One of the most effective treatments is oxygen inhalation therapy. Oxygen concentrators for directly separating oxygen-enriched gas from the inside have been developed, and are becoming increasingly popular as therapeutic devices for oxygen inhalation therapy because of their convenience in use and ease of maintenance.

[0003] As such an oxygen concentrator, an adsorbent oxygen concentrator in which one or more adsorbents capable of selectively adsorbing nitrogen are filled in an adsorbent bed is known. Among them, a pressure using a compressor as an air supply means is known. A variable adsorption type oxygen concentrator is used as a home oxygen inhalation therapy device.

In a pressure fluctuation adsorption type oxygen concentrator,
In general, air is supplied to the adsorption bed by an air compression means, and the inside of the bed is pressurized to adsorb nitrogen in the air to take out oxygen that has not been adsorbed. The adsorbent is released to the atmosphere and decompressed to desorb adsorbed nitrogen to regenerate the adsorbent. Oxygen-enriched air is generated by repeatedly performing the desorption process for regeneration.

[0005]

Since such an oxygen concentrator is used not only at home but also for safety and stability because it is used at home, and it is used every day in ordinary households, it is desired to start it reliably. ing. In such an oxygen concentrator, a use temperature and the like are usually specified, but the minimum use temperature is not always kept in winter, and the device may be started at an extremely low temperature. In such a case, the mechanical resistance of the compressor has increased, and the start-up of the device rarely occurs. To avoid this startup failure,
Various startup performance improvement techniques have been developed. However, start-up failures are still seen.

As a measure for improving the start-up performance, in addition to optimizing the capacity of the mounted compressor, in addition to passing the current higher than the current applied to the normal compressor in a short time at the time of start-up, the rotational torque of the compressor is reduced in a short term. Various known measures such as enhancement are taken. But,
Although the above-mentioned means has a short time, a large current flows through the motor coil, which may affect the life of the motor. It is hard to say that improvements have been made.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to improve the startability of an adsorption-type oxygen concentrator, which is a medical device used at home for a long period of time, and to reduce the mental burden on a patient.

[0008]

Means for Solving the Problems As a result of intensive studies on the above problem, the present inventor has found that the start-up performance can be improved by controlling a sudden increase in the compressor secondary pressure when the oxygen concentrator is started. They found what they could do.

That is, the present invention provides at least one adsorbent bed filled with an adsorbent for selectively adsorbing oxygen or nitrogen,
Compressor means for supplying pressurized air to the adsorption bed, flow path switching means for switching the adsorption and desorption regeneration steps of the adsorption bed, and oxygen supply means for supplying a user with oxygen-enriched gas obtained from the adsorption bed. The adsorption-type oxygen concentrator provided with control means for controlling the secondary pressure of the compressor means, wherein the control means is means for suppressing an increase in the secondary-side pressure when the adsorption-type oxygen concentrator is activated. The present invention provides an adsorption-type oxygen concentrator characterized by the following.

[0010] The present invention is also an adsorption-type oxygen concentrator, wherein the control means is a control means for limiting the number of revolutions at the time of starting the compressor means and increasing the number of revolutions to a rated number of revolutions after a predetermined time. Is provided.

Further, according to the present invention, the control means sets the number of times of switching of the flow path switching means per time at the time of startup to be higher than that in the normal operation, and returns the number of times of switching to a steady value after a predetermined time. The present invention is to provide an adsorption-type oxygen concentrator characterized in that it is a means for carrying out.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The adsorption type oxygen concentrator of the present invention
At least one adsorption bed filled with an adsorbent capable of selectively adsorbing oxygen or nitrogen, a compressor means for supplying pressurized air to the adsorption bed, and a flow path switching means for switching the adsorption and desorption regeneration steps of the adsorption bed And an adsorption-type oxygen concentrator provided with an oxygen supply means for supplying a user with an oxygen-enriched gas obtained from the adsorption bed, wherein an increase in the secondary pressure of the compressor means when the oxygen concentrator is started is suppressed. This is an adsorption-type oxygen concentrator characterized by having a control means for performing the above-mentioned control, and the control means improves the startability of the apparatus and reduces the mental burden on the patient.

[0013] Such a device is provided with control means for preventing the secondary pressure of the compressor means from suddenly increasing when the apparatus is started. As an embodiment, the control means controls the amount of air supplied to the compressor means. Control of the secondary pressure side,
In other words, this is achieved by providing control means for suppressing the number of revolutions of the compressor means. The number of revolutions of the compressor is electrically controlled, as is the control of the number of revolutions of the mounted motor. This electrical control differs depending on the type of motor mounted, and is achieved by controlling the power supply frequency by an inverter or the like for an AC power supply motor, or by controlling the voltage by a DC inverter or the like for a DC power supply motor. Further, among the DC power supply motors, a motor called a stepping motor can control the number of rotations by the frequency of ON / OFF of energization, and can be applied to the present invention.

[0014] The control method supplies the minimum power condition required for the compressor to rotate when the apparatus is started up, and ensures the rotation of the compressor. After that, the rotation speed is controlled according to a predetermined condition.

For example, FIG. 1 shows a sample filled with 5A zeolite, which is an adsorbent for selectively adsorbing nitrogen over oxygen.
An example in which a compressor equipped with an AC motor is mounted in a pressure fluctuation adsorption type oxygen concentrator equipped with this adsorption column is shown. As shown in FIG. 2, the control means keeps the rotation speed of the compressor lower than the rated rotation speed by the control means, so that the shaft torque of the rotating shaft is kept high and the secondary side pressure is hardly increased. This makes it easy to start the compressor even under extremely low temperature conditions. After satisfying the predetermined condition, the compressor is controlled to a separately determined steady-state operating condition, and oxygen concentration is started.

In FIG. 1, a compressor manufactured by THOMAS equipped with an AC motor (100 V / 60 Hz) is used. The motor is started at a frequency of 50 Hz at the time of starting via an inverter, and the motor characteristics (torque curve) and the machine of the compressor are used. The rotational speed of the compressor is controlled by the control curve shown in Table 2 in consideration of the electrical resistance and the like.

In order to operate according to a predetermined condition at the time of start-up, it has a speed monitor such as a tachometer, and adjusts the speed based on the detection result of the speed monitor. Startability is further improved by a rotational speed stabilizing means such as a stabilizing feedback circuit.

In order to avoid such a control, there is a method of selecting a motor having a large rotation torque in advance and securing startability. However, since a motor having a high rotation torque consumes a large amount of power, the oxygen concentrator itself is not used. Leads to the deterioration of the electric energy. Since such a device is used at home, it is necessary to employ a low-power-consumption type compressor from the viewpoint of reducing the economic burden on the user. Is valid.

The compressor means used in the adsorption-type oxygen concentrator of the present invention is not particularly limited.
Compressors such as reciprocating type and scroll type can be used.

As another mode for controlling the sudden rise in the secondary pressure of the compressor means at the time of startup, as shown in FIG. 3, the switching timing of the flow path switching means for switching the adsorption and desorption regeneration steps of the adsorption bed is controlled. The secondary pressure of the compressor means is controlled by setting the number of times of switching of the flow path switching means per time at the time of startup to be higher than that in the normal operation, and performing control to return the number of times of switching to a steady value after a predetermined time. Device. Such a device is a device for controlling a rotary on-off valve connected to a commercially available AC motor by an inverter, and FIG. 4 shows a state where the rotary on-off valve is changed from activation to a rated rotation speed.

The flow path switching means is a means capable of controlling the direction and timing of gas flow, and may be an open / close solenoid valve or a rotary open / close valve.

The switching between pressurization (adsorption step) and depressurization (desorption step) of the adsorbent bed at the time of start-up is performed by increasing the number of times of switching of the flow path switching means per predetermined start-up time as compared with the time of normal operation. , And the number of times of switching is returned to a steady value after a predetermined time.

When a rotary on-off valve is used as the passage switching means, the rotation speed of the valve is inversely proportional to the opening / closing time, and the rotation of the rotary on-off valve is usually electrically controlled using a motor. This electric control is the same as in the case of the above-described compressor, and differs depending on the type of the mounted motor.
If the motor is for AC power supply, power supply frequency control to energize,
A DC power supply motor is achieved by voltage control. Further, the rotation speed of the stepping motor can be controlled by the ON / OFF frequency of energization. Furthermore, it has a rotation speed monitoring means typified by a tachometer and the like, and the startability is further improved by a rotation speed stabilizing means such as a feedback circuit for adjusting and stabilizing the rotation speed based on the detection result of the rotation speed monitoring means. I do.

When an opening / closing solenoid valve is used as the flow path switching means, the opening / closing time can be controlled by a signal from a control circuit.

As a basic method of improving the startability of the apparatus by controlling the flow path switching means, for example, in the case of an oxygen concentrator using a rotary on-off valve means, at the time of starting the apparatus, the conditions shown in FIG. The pressure in the adsorption bed is controlled. By rapidly switching the flow path, that is, switching the pressurization and decompression of the adsorbent bed, the pressure rise of the adsorbent bed is suppressed to a small extent, and by suppressing the rise of the secondary pressure of the compressor, under cryogenic conditions. This also makes it easier to start the compressor. After a certain period of time, it is controlled to a separately determined steady-state operating condition,
Oxygen concentration is started.

Further, as described above, such a device can use both the rotation control of the compressor means and the control of the flow path switching means. Under the conditions, a high startability improvement effect can be obtained.

When the flow path switching means is a rotary on-off valve means,
Adopting a high-speed motor and keeping the number of revolutions at the start high is a contradictory idea to the above-mentioned compressor start in terms of power consumption. However, the power consumption of the rotary on-off valve motor is two orders of magnitude lower than that of the compressor, and the rotation resistance is extremely small. There is no problem with the electric power, and no starting failure of the motor occurs.

In the apparatus of the present invention, when the compressor means and the flow path switching means are controlled under predetermined conditions at the time of starting, the temperature detecting means for detecting the temperature of the adsorption bed or the temperature for detecting the temperature of the compressor. Control that includes detection means and the like and switches the operation of the apparatus from the start-up mode to the steady-state operation mode when the temperature of the adsorption bed is 15 ° C. or more or the temperature of the compressor is 10 ° C. or more is secured. Is preferably performed.

It is also possible to provide a condition that a timer means is provided to automatically control the operation mode from the start mode to the steady operation mode after the operation for a certain period of time. A device equipped with a control means for changing the rotation speed of the compressor means and the flow switching speed, or a counter means, and changing the rotation speed of the compressor means and the switching speed of the flow switching means after a certain number of adsorption / desorption steps. It is preferable that the apparatus is provided with a control unit that performs the control.

[0030]

The adsorption type oxygen concentrator according to the present invention has a capacity of 50H.
Even under the environment of 0 ° C. in the both frequency power supply of z and 60 Hz, the start-up is performed without any abnormality, and the start-up failure machine is not recognized, and the start-up performance under the extremely low temperature environment can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an adsorption-type oxygen concentrator according to the present invention.

FIG. 2 is a control diagram of a rotation speed of a compressor of the adsorption-type oxygen concentrator according to the present invention.

FIG. 3 is a schematic configuration diagram of an adsorption-type oxygen concentrator according to the present invention.

FIG. 4 is a rotation control diagram of a rotary on-off valve (flow path switching means) of the adsorption-type oxygen concentrator of the present invention.

Claims (3)

[Claims] 1. At least one adsorption bed filled with an adsorbent for selectively adsorbing oxygen or nitrogen, compressor means for supplying pressurized air to the adsorption bed, and switching between adsorption and desorption regeneration steps of the adsorption bed In an adsorption-type oxygen concentrator provided with a flow path switching means and an oxygen supply means for supplying a user with oxygen-enriched gas obtained from the adsorption bed, a control means for controlling a secondary pressure of the compressor means is provided. An adsorption-type oxygen concentrator characterized in that the control means is means for suppressing a rise in secondary pressure when the adsorption-type oxygen concentrator is activated. 2. The adsorption-type oxygen according to claim 1, wherein said control means is a control means for limiting the number of revolutions of said compressor means at the time of starting and increasing the number of revolutions to a rated number of revolutions after a predetermined time. Concentrator. 3. The control means sets the number of times of switching of the flow path switching means per time at the start-up time to be higher than that in the steady operation, and performs control for returning the number of times of switching to a steady value after a predetermined time. The method according to claim 1, wherein
3. The adsorption-type oxygen concentrator according to 2.