JPH02256595A - Aspiration gas feeding system - Google Patents

Abstract

PURPOSE:To regenerate and adsorbent for carbon dioxide for removing carbon dioxide from aspiration gas and realize the continuous use of the adsorbent in the title system mounted onto an aeroplane in which aspiration gas from which carbon dioxide is removed is allowed to circulate into a gas feeding passage. CONSTITUTION:The gas for aspiration which is bleeded from the compressor of an engine is supplied into the mask M of a driver through a gas feeding passage L1 by the supplement of the oxygen supplied from an oxygen cylinder 3 in a mixing chamber 2, and the aspiration gas discharged into the mask M is returned into the mixing chamber 2 through a gas circulation passage L2. In this case, the gas circulation passage L2 is branched into two branched passages L2a and L2b through a pair of rotary selector valve 8 and 9 which are interlocked with each other, and carbon dioxide gas removing devices 10a and 10b are installed and the both devices 10a and 10b can be regenerated alternately. The regeneration is carried out by introducing the high temperature air into heating tanks 13a or 13b through a selector valve 25 and by discharging the carbon dioxide adsorbed onto an adsorbent 12.

Description

Detailed Description of the Invention A0 Object of the Invention (1) Industrial Field of Application The present invention relates to a respirator for supplying breathing gas to a mask worn by the crew of an aircraft flying at high altitudes with air filtration. The present invention relates to a respiratory gas supply system, and more particularly to a respiratory gas supply system that makes it possible to reuse oxygen remaining in exhaled air by circulating exhaled air from which carbon dioxide has been separated through a gas supply path.

(2) Prior Art In conventional aircraft, the cabin pressure is normally maintained at a value slightly higher than the outside air pressure. Therefore, when an aircraft flies at a high altitude where the air is thin, the cabin pressure is low and the oxygen partial pressure is also low. This causes problems such as a lack of oxygen for the passengers and impaired judgment by the passengers.

For this reason, aircraft flying at high altitudes are equipped with a breathing gas supply system that supplies breathing gas to oxygen supplementation masks worn by passengers. This breathing gas supply system supplies breathing gas such as oxygen from an oxygen supply source such as an oxygen cylinder or an oxygen condensing device and air bled from an engine to the mask, and the pressure of the supplied breathing gas. The pressure also decreases as the cabin pressure decreases. By increasing the oxygen concentration as the pressure of the breathing gas decreases, the oxygen partial pressure of the breathing gas supplied to the mask is maintained substantially constant. In conventional respiratory gas supply systems, the respiratory gas supplied to the mask is discharged into the cabin when the mask wearer inhales and exhales the gas.

However, since the breathing gas supplied to the mask has a high oxygen concentration, a large amount of oxygen still remains in the gas that is breathed out after the mask wearer inhales the breathing gas, that is, the breath. Therefore, if exhaled air containing a large amount of oxygen is released into the aircraft as it is, the produced oxygen will be wasted.

In order to eliminate waste, the oxygen-rich exhaled air is passed through a carbon dioxide removal device or the like to be regenerated as a gas with a high oxygen content, and this regenerated gas is mixed with the oxygen from the oxygen supply source. Breathing gas supply systems have been proposed that circulate through the mask.

(3) Problems to be solved by the invention However,
The above-mentioned conventional breathing gas supply system has a problem in that when carbon dioxide in exhaled breath is continuously adsorbed and removed by the adsorbent of the carbon dioxide removal device, the carbon dioxide adsorbent gradually deteriorates and performance decreases. was there.

The present invention has been made in view of the above-mentioned circumstances, and is a breathing gas supply system that enables continuous use of a carbon dioxide adsorbent that removes carbon dioxide from exhaled breath of passengers by regenerating it. The challenge is to provide the following.

B0 Structure of the Invention (1) Means for Solving the Problems In order to solve the above problems, the present invention provides a gas supply path that supplies breathing gas extracted from an engine to a mask, and a gas supply path that is connected to the gas supply path. an oxygen supply source that replenishes oxygen to the gas supply path, a gas circulation path that circulates exhaled air exhaled into the mask to the gas supply path, and adsorbs carbon dioxide in the exhaled air discharged into the gas circulation path. In a breathing gas supply system that includes a carbon dioxide removal device having an adsorbent to remove carbon dioxide and reuses the carbon dioxide reduced gas obtained by the carbon dioxide removal device as breathing gas, the amount of carbon dioxide adsorbed is saturated. The present invention is characterized by comprising a regenerating means for separating carbon dioxide from the adsorbent that has approached the temperature, and an exhaust path for discharging the separated carbon dioxide from the carbon dioxide removal device.

It is effective to provide two carbon dioxide removal devices, and while one carbon dioxide removal device adsorbs and removes carbon dioxide, the adsorbent in the other carbon dioxide removal device is regenerated.

Further, as the adsorbent, for example, activated carbon or molecular sheep can be used.

When these adsorbents are employed, the regeneration means includes a heating tank that heats the adsorbent of the carbon dioxide removal device;
The heating tank may be configured with a high-temperature bleed passage that introduces high-temperature air extracted from the engine into the heating tank.

(2) Effect According to the present invention having the above-described configuration, the breathing gas bled from the engine into the gas supply path is supplied with oxygen from the oxygen supply source and then supplied to the mask, where a portion of the breathing gas is supplied to the mask. The exhaled air is depleted of oxygen and is discharged into the gas circulation path. The exhaled air discharged into the gas circulation path passes through the adsorbent of the carbon dioxide removal device, becomes a carbon dioxide-depleted gas, and is returned to the gas supply path to be reused as breathing gas. When the amount of carbon dioxide adsorbed by the adsorbent of the carbon dioxide removal device approaches a saturated state, the regeneration means separates carbon dioxide from the adsorbent, and the adsorbent is regenerated into a state capable of adsorbing carbon dioxide again.

If two carbon dioxide removal devices are provided and the adsorbent is regenerated alternately, one of the carbon dioxide removal devices can always function and remove carbon dioxide continuously.

Furthermore, if activated carbon or molecular sieve is adopted as the adsorbent, and the regeneration means is composed of a heating tank that heats the adsorbent of the carbon dioxide removal device and a high-temperature oil passage that introduces high-temperature air extracted from the engine. , the adsorbent can be thermally regenerated without using a special heat source.

(3) Examples Hereinafter, the present invention will be described in detail based on the drawings.

A breathing gas supply system S according to an embodiment of the present invention shown in FIG. Gas supply path L that supplies the mask M
1. An oxygen supply source 3 such as an oxygen cylinder is connected to a mixing chamber 2 provided in the middle of the gas supply path L1 via a flow rate regulating valve 4, and oxygen is supplied to the bleed air from the engine in this mixing chamber 2. Breathing gas is supplied to the inside of the mask M through the gas supply valve 5 and is used for the occupant's breathing. The exhaled breath of the passenger discharged into the inside of the mask M is discharged into the gas circulation path L2 through the gas discharge valve 6, and circulated to the mixing chamber 2 through this gas circulation path L2.

A part of the exhaled air is removed from an exhaust valve 7 provided in the gas circulation path L2.
are discharged into or out of the aircraft via the

Two branch paths L2a and L2b are provided between a pair of mutually interlocking rotary switching valves 8 and 90 interposed in the gas circulation path L2.
are arranged in parallel, and carbon dioxide removal devices 10a and 10b are arranged in each branch path L2a and L2b, respectively. And these carbon dioxide removal devices 10a, 10b
is selectively connected to the gas circulation path L2 by opening and closing the rotary switching valve 8.9. Further, from the gas circulation path L2 connecting the rotary switching valve 9 and the mixing chamber 2, an auxiliary path L3 having an orifice 11 in the middle is connected back to the switching valve 9, and the other switching valve 8 is connected to a low-pressure machine. An exhaust path L4 communicating with the outside is connected. Note that this exhaust path L4 can also be communicated with the inside of the machine.

The interior of the carbon dioxide removal devices 10a and 10b is filled with a carbon dioxide adsorbent 12 such as activated carbon, molecular sieve 4A, molecular sieve 5A, or molecular sieve 13X. As shown in FIG. 2, the adsorbent 12 has a characteristic that the maximum amount of carbon dioxide that can be adsorbed decreases as the temperature increases at any partial pressure of carbon dioxide. Therefore, when the adsorbent 12 that has adsorbed carbon dioxide and reached a saturated state is heated, the adsorbed carbon dioxide is separated and released, and the adsorbent is regenerated into a state capable of adsorbing carbon dioxide again.

An adsorbent 1 is placed on the outer periphery of the carbon dioxide removal devices 10a and 10b.
Heating tanks 13a and 13b are provided so as to surround 2. The heating tanks 13a and 13b are provided with high-temperature bleed air passages L5a and L5b that guide high-temperature air extracted from the engine via a rotary switching valve 15 that opens and closes in conjunction with the pair of rotary switching valves 8 and 9 by an interlocking mechanism 14. , and high-temperature exhaust paths L6a and L6b that discharge this high-temperature air to the outside of the machine are connected.

The heating tanks 13a, 13b and the high temperature bleed passage L5a
, L5b constitute an adsorbent regeneration means.

Next, the operation of the embodiment of the present invention having the above-described configuration will be explained.

The breathing gas extracted from the engine compressor into the gas supply path L1 reaches the mixing chamber 2 via the flow rate adjustment valve 1,
Here, after oxygen is supplied from the oxygen supply source 3, it is supplied into the passenger's mask M through the gas supply valve 5. On the other hand, the exhaled breath of the passenger passes through the gas exhaust valve 6 and passes through the gas circulation path L2.
A part of it is discharged to the outside of the machine via the exhaust valve 7.

Most of the exhaled air discharged into the gas circulation path L2 is introduced into one carbon dioxide removal device 10a via the rotary switching valve 8 located at the position shown in the figure and the branch path L2a, and the adsorbent 12 filled therein is introduced into one of the carbon dioxide removal devices 10a. pass through. At this time, carbon dioxide contained in the exhaled breath is adsorbed and removed by the adsorbent 12, and the air with increased oxygen content is circulated to the mixing chamber 2 via the branch path L2a, the rotary switching valve 9, and the gas circulation path L2. , which will be used again for passenger breathing.

At this time, the heating tank 1 of the other carbon dioxide removal device 10b
3b, high-temperature air bled from the engine is introduced through the rotary switching valve 15 located at the illustrated position and the high-temperature bleed passage L5b, and the adsorbent 1 is heated by this high-temperature air.
2 releases the carbon dioxide that has been adsorbed up to that point. A part of the air circulating from the rotary switching valve 9 to the mixing chamber 2 is introduced into the carbon dioxide removal device 10b via the auxiliary path L3 having the orifice 11, the rotary switching valve 9, and the branch path L2b, and is heated. Together with the separated carbon dioxide, it is discharged to the outside of the machine via the branch path L2b, the rotary switching valve 8, and the exhaust path L4.

As described above, while carbon dioxide is being adsorbed and removed by the adsorbent 12 of one carbon dioxide removing device 10a, the adsorbent 12 of the other carbon dioxide removing device 10b is heated and regenerated. Then, the adsorbent 12 of the carbon dioxide removal device 10a adsorbs carbon dioxide and approaches a saturated state (and the three rotary switching valves 8, 9, 15
4, and this time carbon dioxide is adsorbed and removed in the carbon dioxide removal device tab, and the adsorbent 12 of the carbon dioxide removal device 10a is heated and regenerated. In this way, the rotary switching valve 8.
By alternately switching 9.15, carbon dioxide can be adsorbed and removed in either of the carbon dioxide removal devices 10a, 10b.

According to the above-mentioned embodiment, two carbon dioxide removal devices are provided and the adsorbent is heated and regenerated alternately, so that one of the carbon dioxide removal devices always functions to continuously remove carbon dioxide. It can be done by

Furthermore, since high-temperature air extracted from the engine is introduced into the heating tank that contacts the adsorbent of the carbon dioxide removal device, the adsorbent can be heated and regenerated without using a special heat source.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the embodiments described above, and various small design changes may be made without departing from the scope of the present invention as set forth in the claims. It is possible to do so.

For example, the number of carbon dioxide removal devices 10a, 10b does not necessarily have to be two, and it is also possible to have one or three or more. Moreover, instead of introducing high-temperature air that heats the adsorbent 12 into the heating tanks 13a and 13b, this high-temperature air is passed through a pollutant removal filter, and then the carbon dioxide removal device 10a filled with the adsorbent 12, 10b
It is also possible to introduce the carbon dioxide directly into the inside of the machine, and in this way, the separated carbon dioxide can be released outside the machine together with the high temperature air. Furthermore, instead of heating the adsorbent 12 with high-temperature air extracted from the engine, it is also possible to heat the adsorbent 12 using another heat source such as an electric heater. Furthermore, as a means for regenerating the adsorbent, it is also possible to employ means for sucking and discharging the gas inside the carbon dioxide removal apparatuses 10a and 10b to lower the partial pressure of carbon dioxide therein.

Effects of the C0 Invention According to the above-described breathing gas supply system of the present invention, the carbon dioxide adsorbent that has reached a saturated state is regenerated by the regeneration means to a state capable of adsorbing carbon dioxide again. Can be used repeatedly. Therefore, not only is it not necessary to frequently replace the adsorbent in the carbon dioxide removal device, but also it is possible to reduce the amount of adsorbent and downsize the carbon dioxide removal device.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram of a breathing gas supply system according to an embodiment of the present invention, and FIG. 2 is a graph showing the temperature characteristics of an adsorbent. M...Mask, Ll...Gas supply path, L2...Gas circulation path, L5a, L5b...High temperature bleed path, L6a,
L6b...High temperature exhaust path, 3...Oxygen supply source, lla
, 11b... Carbon dioxide removal device, 12... Adsorbent, 13a, 13b... Heating tank equilibrium adsorption amount (g/100gMS)

Claims (1)

[Claims] A gas supply path that supplies breathing gas extracted from the engine to the mask, an oxygen supply source that is connected to this gas supply path and supplies oxygen to the gas supply path, and an oxygen supply source that supplies oxygen to the gas supply path; The carbon dioxide removal device includes a gas circulation path that circulates exhaled air to the gas supply path, and a carbon dioxide removal device that has an adsorbent that adsorbs and removes carbon dioxide in the breath discharged to the gas circulation path. A breathing gas supply system that reuses the obtained carbon dioxide reduced gas as a breathing gas, comprising: a regeneration means for separating carbon dioxide from the adsorbent whose adsorption amount of carbon dioxide has approached a saturated state; and an exhaust path for discharging carbon dioxide from the carbon dioxide removal device.