DE3105016A1 - Breathing apparatus - Google Patents

Description

Andrejewski, Honke & Partner, patent attorneys in Essen

The invention relates generally to a device for Control of the flow of gaseous media from a region of higher pressure into a region of lower pressure and in particular a regenerative breathing apparatus with a semi-closed Circuit for divers.

The term "regenerative breathing apparatus" is usually understood to mean that in such a device that exhaled by the diver Gas is partially rebuilt or regenerated, to be inhaled again, as opposed to one Breathing apparatus with an open breathing circuit, in which the one exhaled once Gas is expelled into the void. The regeneration of the breathing gas can take place in the catfish »that simply more freshness Air is added to the existing mixture and the excess amount is expelled into the void. This system was in use in diving helmets since the beginning of diving operations, although not usually considered regenerative.

A more modern regenerative breathing apparatus also works with a method of removing the carbon dioxide that is caused by the metabolism of the diver is generated by passing the exhaled gas mixture through a filter, which contains a chemical which reacts with the carbon dioxide and extracts the same from the gas, so that the gas mixture is restored can be inhaled. This flow of regenerative air or gas mixture must be maintained in order to avoid that of the diver to replace used oxygen * If a gas mixture is used becomes, in which the oxygen substitute by a gas is accompanied, which can be regarded as physiologically inert insofar as it is involved in the metabolic activity of the

130061/0466

Andrejewski, Honke & Partner, patent attorneys in Essen

Diver does not participate, such as nitrogen or Helium, then the excess volume must be blown off.

Because the diver himself is a dangerous depletion of oxygen is not sensitive in the breathing circuit and its oxygen consumption is variable, the oxygen partial pressure in the breathing circuit must the device can be controlled in such a way that it does not fall below a predetermined value even with an increased metabolism decreases, even at the lowest possible value of the metabolism exceeds a predetermined value.

Respiratory equipment of those offered today that meets these conditions Kinds can be viewed under two main terms. For this purpose there are devices with a completely closed circuit, in which the gas in the breathing circuit consists either of pure oxygen or in which the oxygen partial pressure is monitored and is kept at a predetermined value, and there are devices with a semi-closed circuit in which the oxygen partial pressure fluctuates within allowable limits by supplying either a steady or intermittent flow of mixed gases which is controlled by the diver's breathing rate. Both device types rely on a filter arrangement, to remove the carbon dioxide from the exhaled gas mixture.

In devices with a semi-closed circuit, in which a steady flow of gases and the control of this flow is provided, with whichever type the invention is concerned, it has hitherto been very general practice to use premixed

130061/0466

Andrejewski, Honke & Partner / patent attorneys in Essen

Gases, one of which is oxygen, in high pressure cylinders too compress, which are usually carried by the diver. The gas mixture of these bottles or the gas mixture of one Compressor, if the mixture is air, it is fed to a pressure reducing valve, with which the gas pressure is reduced to a set value which in most devices is more than twice the highest ambient pressure at which the diver is using the device can. With some devices, this value is increased when the The diver's ambient pressure increases with increasing depth. The reduced pressure gas is used in the breathing apparatus fed through a small opening, the dimensions of which are so large that, driven by the set reduced Pressure, sufficient gas can flow through it to satisfy the equation below and a constant mass flow over all To maintain depths to which the diver can descend:

η Mg ~ G
_υ ο _{F. c}

where 0 = the space ratio (under normal conditions) of the oxygen in the breathing circuit so that the partial pressure of the oxygen remains between 0.16 and 2.0 at;

M = the space ratio (under normal conditions) of the oxygen in the gas mixture supplied to the breathing circuit;

P = the inflow to (in normal conditions) the breathing circuit supplied gas; and

C = the inflow of oxygen (under normal conditions) consumed by the diver, usually assumed is that young men working as divers are at least 0.25 l / min (in normal conditions) and at most steadily Consume 3 l / min.

130061/0468

Andrejewski, Honke & Partner, patent attorneys in Essen

Devices controlled in this way have two defects. There yourself the reduced gas pressure is still relatively high, there are the openings through which the gas mixture must flow, small and light. Dust particles or ice deposits can be blocked, which can settle out of any water vapor in the gas. Second, the amount of gas delivered to the diver is either fixes or even increases with increasing depth. As a result, more gas is supplied to the diver than he is at increasing depth is required, and a gas must be supplied which is richer in oxygen than necessary to be safe to go and still be economical beyond the depths that can be reached by the diver. On the other hand, if a gas mixture, which is oxygen-rich, is supplied in order to achieve a low consumption of the supply, the diver is in relation to the depth that he can absolutely safely reach, due to the increasing partial pressure of the oxygen in the breathing circuit and because of this Partial pressure approaches 2.0 at, limited.

The invention has set itself the task of training a breathing apparatus with a semi-closed circuit for divers in such a way that that the partial pressure of the oxygen in the gas which is inhaled by the diver, automatically between a predetermined upper and lower limit over the full depth at which the diver has to work is controlled and maintained.

Characterized is a breathing apparatus according to the invention of the aforementioned ' th type essentially by arrangements for reducing the mass of breathable gas supplied to the breathing circuit of the device, which respond to the external pressure to which the diver is exposed,

T30σβ1 / 0468

Andrejewski, Honke & Partner, patent attorneys in Essen

and by means of which the amount of breathable gas flowing into the breathing circuit of the device can be reduced with increasing diving depth and thus increasing pressure, the device operating according to the formula «· = t , where

- the space ratio (under normal conditions) of the oxygen in the breathing circuit so that the partial pressure of oxygen remains between 0.16 and 2.0 at;

M = the space ratio (under normal conditions) of the oxygen in the gas mixture supplied to the breathing circuit;

P = the inflow to (in normal conditions) the breathing circuit supplied gas;

C = the inflow amount to (with normal status) from the diver consumed oxygen, which is commonly believed to be young divers working as divers Men at least 0.25 l / fflin (under normal conditions) and Consume at most steadily 2! / min; and

D = the absolute depth in at at any point in the diving process,

whereby the oxygen partial pressure in the breathing circuit is at maximum or Minimum consumption of oxygen between 0.16 and 2.0 at is stable is.

The invention is based on the finding that the aforementioned equation 0 «= must be modified ⁱⁿ d® ^r catfish,

130061 / 046B

Andrejewsld, Hanke & Partner, patent attorneys in Essen

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that, instead of predetermined flow rates to generate a safe partial pressure at a certain depth, the flow rates are steady according to the depth reached by the diver can be set.

According to a further special feature of the invention are because of When using very low gas pressures, the gas passage openings in the entire device were sized so large that they were blocked by dust particles or ice, which could arise from water vapor contained in the gases of the mixture, cannot be blocked. Furthermore can in the case of a breathing apparatus according to the invention, the device opens the gas passage only occlude while a drive pressure is maintained and that gas in excess of this pressure is constant flows out through a large opening into the breathing circuit. As soon as the drive pressure drops, the pressure caused by this is reduced Residual force opened the valve that had shut off the gas supply, so that the device is absolutely fail-safe.

In one embodiment of the invention, these working principles are implemented by a valve in the pressurized gas supply to the breathing circuit meets, which has a chamber to which the compressed gas is fed flexible arrangements are provided which close the chamber, the opposite side of which is exposed to pressure is exposed at the depth reached, the flexible assembly being connected to an inlet valve to the chamber and a has an outlet hole connected to the breathing circuit to which compressible organs are connected through which the dimension the bore at the outlet looh is controllable. So the chamber can be closed by a flexible membrane

130061/0466

Andrejewski, Honke & Partner, patent attorneys in Essen

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which a system of flexible and compressible components is arranged, over which a rigid plate lies, which with connected to the valve through which the gas or gas mixture is forwarded to the chamber. Therefore, if the plate is removed from either the membrane or the compressible components or is moved by both together, the valve is actuated to close the flow of gas or the flow of gas into the chamber steer. The excess pressure between the chamber and the other side of the membrane is at most 10% greater than the absolute Ambient pressure on this side of the membrane at any point during the immersion process.

In addition to opening and closing the valve, the plate, compressible components and diaphragm result in the have a total of a Durohgangsloch, which allows the gas or the gas mixture, from the chamber into the breathing circuit flow, a check on the diameter of the hole accordingly the pressure to which the compressible components are subjected and thereby a further control over the gas mass entering the breathing circuit.

A main advantage of the invention is that the current fresh gas or a fresh Sasmisehung automatically can be controlled in such a way that the oxygen ratio (at normal conditions) in the breathing system of the equation jj = Η £ * Ξ§ follows, creating one in breathing apparatus, which works on the principle work in a semi-closed circuit, maximum economy of safety gas consumption can be achieved.

13 0 0 61/0 46fr

Andrejewski, Honke & Partner, patent attorneys in Essen

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Since a very low pressure differential is used to reduce the Forcing gas through the hole from the chamber into the breathing circuit is the speed of the gas flowing through the hole Gas so that the temperature drop in the flowing gas is low enough to avoid any risk of ice forming in the gas or water vapor possibly contained in the gas mixture, which could clog the channels, is practically suppressed will. As a result of this low pressure differential, the opening can also be kept so large that the possibility any ice particles that may arise or dust particles resulting from the high pressure gas flow are eliminated, to block the channels so that filters are not required. In addition, the partial pressure of the oxygen in the breathing system can through the constant minimum oxygen consumption of the diver can be kept at a value below 2.0 at, so that there is also no depth limit up to which this device can be used as a result of oxygen poisoning. There is also the gas supply increases with decreasing depth, the diver does not need to switch on an extra gas supply in the breathing circuit to be sure, that the partial pressure of oxygen during the ascent over the safety minimum remains. The use of a balanced valve to control the supply of high pressure gas in the system requires little force to operate and consequently reduces the size of the sensitive components for any given level of accuracy required.

The invention is described below with reference to one in the drawing illustrated embodiment explained in detail; it shows

Pig.l shows a section through a breathing apparatus according to the invention from the side viewed in a schematic representation; and

Pig.2 shows an enlarged excerpt from the construction of Pig.l.

13006 1/0468

Andrejewski, Honke & Partner, patent attorneys in Essen

The regenerative breathing apparatus according to the invention shown in the drawing has a semi-closed circuit for divers a chamber 1, which is closed by a flexible membrane 2, which is connected to a sealing ring 3, which is in conditions 4 engages the inner wall of the chamber. The membrane 2 has an outlet hole 5 * which connects directly to the one not shown Breathing circuit for the diver is connected. On the membrane 2 around the hole 5 there is a flexible ring 6 with a the center opening 7 aligned with the hole 5 and a resilient one Ring 6 surrounding another ring 8 made of an easily compressible material such as neoprene foam and a on the outside of this ring 8 is another ring 9 also mounted from flexible material «With their from the Diaphragm 2 facing away from the rings 6 and 8 are rare with a rigid plate 10, which has a center hole 11 aligned with the opening 7. On the plate 10 is a connecting part 12 attached, which is attached to a carrier 13 for a movable Valve member 14 engages. This valve member 14 carries a valve seat 15, which with the open end of a cylinder 16 can interact, the movable valve member 14 being guided by a piston 17 which protrudes into the cylinder 16. The cylinder 16 is connected to a source of pressurized gas via a conduit 18 which passes through the chamber 1 and is sealed on the outer wall.

Therefore, if the compressed gas for the first time via line 18 in the Chamber 1 and cylinder 16 is introduced, there is no pressure difference available for the compressed gas through the membrane 2, so that the membrane does not bend at first

130061/0468

Andrejewski, Honke & Partner, patent attorneys in Essen

and the valve seat 16 at the open end of the cylinder 16 remains free. Any pressure exerted by the inflowing gas acts on the piston 17 and the valve seat 15 with the same static Pressure, which is caused by the velocity gradient of the over its Surface from the cylinder 16 and into the chamber 1 flowing gas is reduced. As a result, there is a resulting one Force tending to pull the valve seat against the cylinder and the width to which the valve is open decreases until the forces acting on the piston and valve seat are equal.

If gas continues to flow into the chamber 1, the pressure in the chamber begins opposite that outside the chamber and thus on the pressure acting on the opposite side of the membrane, so that a gas flow arises through the outlet hole of the membrane which flows into the breathing circuit. As a result of the pressure difference between the chamber 1 and the opposite Side of the diaphragm 2, the diaphragm is bent outwardly opposite the chamber, through which movement the valve seat 15 against the Cylinder 16 is pulled, whereby the flow of gas into the chamber 1 is reduced or even shut off. Additionally have the closed cells of the foam ring 8 an original Pressure of approximately 1 at, so that any pressure in the Chamber over 1 at leads to a compression of the ring 8. As a result of the ring 8 by its attachment to the membrane 2 and force exerted on the plate 10, the Ring 8 preferably together in a direction perpendicular to the plane of the plate and the membrane. Regardless of the closed cells of compressed gas, the ring 8

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Andrejewski, Honke & Partner, patent attorneys in Essen

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bulge on the inside and outside »because the total load on the constrained surfaces of the hanging 8 exceeds the total load on the non-constrained circumference, whereby an internal hydrostatic pressure is generated which is higher than the pressure in the chamber. This druok over is through compensated for the elastic tension induced when the elastic material of the ring 8 bulges.

Under the action of the pressure in, the chamber on the Ring 8 exerted forces, which are transmitted to the plate 10 and the membrane 2, the ring 6 is also pressed together and deformed in such a way that it bulges mainly inwards and thereby effectively the diameter of the opening 7 changes.

As a result, the clear effect of the foregoing results described features in their interaction a control for the gas flow from the gas supply into the breathing circuit, which only depends on the ambient pressure and not on the pressure of the gas supply itself.

The ring 9 effectively acts as an ansonlagorgan so that when the plate 10 approaches the membrane 2 when the rings 6 and 8 are compressed, the plate 10 is prevented from further approaching the membrane 2 at a greater immersion depth, whereby the gas flow from the chamber is controlled in the Ateiükreis in connection with the action of the other aforementioned components and whereby the gas flow in the breathing circuit fulfills the formula ψ- =.

130061/0466

Andrejewski, Honke & Partner, patent attorneys in Essen

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In addition to the automatic control of the gas flow into the breathing circuit according to the depth reached by a diver is also due to the design of the breathing apparatus according to the invention automatic compensation for any pressure drop in the gas supply to the chamber is achieved. If, as is usually the case, the gas is supplied via gas bottles carried by the diver, then the breathing apparatus according to the invention works, even if the The gas supply fails because the gas bottles are emptied and the pressure continues to drop, because, as already explained, it is operationally reliable Work of the breathing apparatus according to the invention does not depend on the pressure of the gas from the supply point.

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Claims (1)

English Street, Hull, ΗΙΓ5 2DU, England and DAVID HAYGREEN & ASSOCIATES LIMITED
Trafalgar House, 29 Park Place,
Leeds, LSI 2SP, England Respiratory Equipment. Expectations. I, I breathing apparatus with semi-closed circuit for divers, characterized by instructions for reducing : decoration of the breathable mass supplied to the breathing circuit of the device Gas, which on the external pressure to which the diver is exposed is, respond, and through which with increasing diving depth and thus increasing pressure the amount of in the breathing circuit of the ! Breathable gas flowing into the device can be reduced, the Andrejewski, Honke & Partner, patent attorneys in Essen - 2 - The device works according to the * formula g · =, where O = the space ratio (under normal conditions) of the oxygen in the breathing circuit so that the partial pressure of the oxygen remains between 0.16 and 2.0 at; M = the space ratio (under normal conditions) of the oxygen in the gas mixture supplied to the breathing circuit; F = the inflow amount to (in normal conditions) the breathing circuit supplied gas; C = the inflow amount to (under normal conditions) from the diver consumed oxygen, which is commonly believed to be young divers working as divers Mannöa? · At least 0.25 l / min (under normal conditions) and Consume at most continuously j5 l / min; and D = the absolute depth in at at any point in the diving process, whereby the oxygen partial pressure in the breathing circuit is at maximum or Minimum consumption of oxygen between 0.16 and 2.0 at can be kept is. 2. Breathing apparatus according to claim 1, characterized in that the gas port openings in the entire device are dimensioned so large that that they are not caused by dust particles or ice, which could arise from water vapor contained in the gases of the mixture are blockable. 130061/0466 Andrejewski, Honke & Partner, patent attorneys in Essen j5. Breathing apparatus according to claim 1 or 2, characterized in that the gas passage to the apparatus can be reduced when the drive pressure continues, the gas exerting this pressure constantly flowing out into the breathing circuit and the arrangement for reducing the mass of breathable gas opens when the drive pressure drops, whereby the The device is absolutely safe to operate. 4. Breathing apparatus according to one of claims 1 to 3, characterized in that that a valve (14, 15 »16) in a chamber (1) is provided and that within the chamber with the valve organs (6, 8, 10) are connected through which the Valve can be opened or closed according to the ambient pressure inside the chamber. 5 · Breathing apparatus according to claim 4, characterized in that the Chamber (1) is closed by a flexible organ (2) and the opposite side of this flexible organ is subject to pressure is exposed to the depth in which the breathing apparatus is located that the flexible organ with the inlet valve (14, 15, 16) for Chamber is connected and an outlet hole connected to the breathing circuit (5) and that the Auslaßlooh associated organs (6, 8, 10) are provided through which the dimension of the Bore (7) on Auslaßlooh is controllable. 6. Breathing apparatus according to claim 5 »characterized in that the chamber (1) is closed by a flexible membrane (2), on which a system of flexible and compressible components (6, 8) is mounted, over parts a rigid plate (10) is mounted, this rigid plate is connected to the valve (14, 15, l6) through which the gas or a gas mixture is supplied to the chamber. 130061/0468 Andrejewski, Honke & Partner, patent attorneys in Essen _ ij. - 7. Breathing apparatus according to claim 5 or 6, characterized in that that on the flexible membrane (2) a relatively inflexible component 7. Is mounted by allowing the movement of the rigid Plate (10) against the flexible membrane when compressing the system (6, 8) made of flexible and compressible components is limited. 8. Breathing apparatus according to one of claims 5 to 7, characterized in that that the system of flexible and compressible components (6, 8) and the rigid plate (10) openings (11, 7) which cooperate with the outlet hole (5) of the flexible membrane (2). 130061/0466