Patent Application
20240253756
The present invention provides a breathable gas supply apparatus. Preferably, the invention provides an interface between a diving rebreather or other breathing gas reclamation unit and a helmet or full-face mask.
A full-face mask or helmet is usually supplied with breathable gas from a compressed gas cylinder through a demand valve/regulator. No bite mouthpiece is required. This is typically termed open-circuit. Rebreather technology uses a closed-circuit principle, and the two technologies are both different and not readily combined in a full-face mask or helmet.
For instance, replacement of an open-circuit regulator with a rebreather results in flow restrictions and bi-directional flow in various parts of the apparatus, leading to restriction of breathing and build-up of carbon dioxide. Rebreathers rely on wide passages as one's breathing is the only driving force, whereas open-circuit systems use compressed gas and, thus, the standard masks are provided with narrow flow passages unsuitable for rebreather use. Typically a rebreather used with a full-face mask still requires a bite mouthpiece, to prevent flooding the rebreather in the case of water ingress, and to prevent mixing of fresh and exhaled gas in the mask cavity, worsening the above problems.
Although the two technologies are known and one might theoretically think of combining them, it is reiterated that the technologies are different and not readily combined, unless various problems are addressed and solved through inventive insight. For example, if one did combine the technologies this brings with it the serious disadvantage of excessive protrusion of the apparatus from the head, generating torque, which resists head movement and, potentially, displaces the seal in the case of a full-face mask. Further, this increased “dead space” in which fresh and exhaled gas may mix, and this risk of leakage, means that the rebreather still requires a bite mouthpiece, and this removes the normal advantage of using a full face mask which allows easy communication as one can readily talk, and unrestricted breathing as one can fully open the mouth.
It is well know that a bite mouthpiece obstructs speech and also provides breathing resistance.
The present invention is aimed at solving these and other problems associated with the prior art, or simple combinations thereof.
According to a first aspect, the present invention provides breathable gas supply apparatus, for connecting with a diving face mask or helmet, the gas supply apparatus is connectable with an inlet and outlet of a rebreather or reclaim unit for a first supply of breathable gas for closed-circuit use, and connectable with a second supply of breathable gas for open-circuit use, wherein, the apparatus comprises:
Preferably, the first valve means is operably connected to the second valve means.
Preferably, the second valve means is configured such that sealing the first valve means automatically opens the second valve means.
Preferably, following opening of the second valve means, the apparatus is configured such that re-opening of the first valve means leaves open the second valve means.
Preferably, the apparatus is configured to be capable of supplying breathable gas from both said rebreather and said second supply of breathable gas at the same time. In that context opening of the first valve means does not correspond to sealing of the second valve means.
Preferably, the first valve means is operably connected to at least part of the third valve means.
Preferably, the first valve means comprises a linkage for directly contacting the second valve means. Most preferably, the linkage further comprises a (flexible) connector for acting upon at least part of the third valve means.
Preferably, the third valve means is an exhaust valve comprising an actuator configured to enable exhausting exhaled gas during open-circuit use and retaining exhaled gas during closed-circuit use.
Preferably, the (flexible) connector acts upon a movable bias plate to alter its condition from exhausting exhaled gas during open-circuit use to retaining exhaled gas during closed-circuit use.
Preferably, the (flexible) connector and actuator or bias plate are configured to be manually operable during closed-circuit use so as to manually vent gas and/or liquids.
Preferably, the third valve means is configured to be manually openable while the first valve means is open and the second valve means is closed.
Most preferably, the bias plate is operable between first and second conditions: in the first condition, the bias plate is configured to bias the exhaust valve closed for closed-circuit use; and, in the second condition, the bias plate is configured not to hinder operation of the exhaust valve. Further preferably, in the first condition whilst biased closed against normal exit gas pressure, the exhaust valve is configured to remain manually operable.
Preferably, the second supply of breathable gas is a compressed source of breathable gas.
Preferably, the second valve means is configured to act autonomously of the first valve means. Preferably, the third valve means is configured to act autonomously of the first valve means.
Preferably, the second valve means is configured to be manually sealable.
Most preferably, the first valve means comprises:
Preferably, the first and/or second rebreather valve is/are operably connected to the second and/or at least part of the third valve means.
Most preferably, the first and/or second rebreather valve is operably connected to the second valve means and at least part of the third valve means and is, thereby, capable of affecting three valves simultaneously.
Preferably, the first or second rebreather valve is operably connected to the other rebreather valve and, thereby, capable of operating both rebreather valves simultaneously.
Preferably, one of the two rebreather valves comprises a linkage for operating both the first rebreather valve and second valve means simultaneously, so as to close the connection to or from said rebreather or reclaim unit and open supply from said second supply of breathable gas.
Preferably, the linkage is operably connected to an/the actuator of the third valve means, so as to affect the third valve means simultaneously.
Most preferably, operation of one rebreather valve opens the gas supply from the second supply of breathable gas and alters the configuration of the bias plate in the exhaust valve.
Preferably, the apparatus comprises an oronasal mask comprising one or more passageways connectable with said rebreather or reclaim unit for directly supplying gas to or directly exiting gas from the oronasal mask.
Most preferably, the oronasal mask comprises two separate passageways, one for supplying breathable gas from said rebreather or reclaim unit, the other for exiting exhaled gas to said rebreather or reclaim unit.
Preferably, the oronasal mask further comprises: one or more one-way valves for supplying breathable gas from said second source via a screen region of said face mask or helmet; and an/the exhaust valve.
Most preferably, the one-way valves are check valves.
Preferably, the first valve means is configured to be connectable to an auxiliary port of said face mask or helmet.
Preferably, the first and second rebreather valves are configured to be located to one or more side regions of the face mask/helmet, to reduce torque in use.
Preferably, the apparatus further comprises a surface air valve, communications apparatus and/or drinking/feeding apparatus.
Preferably, connection of one or more valve means/rebreather valves to a standard face mask or helmet in auxiliary ports 1 and 2 provides a modular aspect to the invention, in which the one or more valve means and the face mask or helmet are more easily interchanged should the need require. Most preferably, a first rebreather valve is configured to connect to auxiliary port 1 of a standard diving face mask or helmet, and a second rebreather valve is configured to connect to auxiliary port 2 of a standard diving face mask or helmet.
According to a second aspect, the present invention provides a diving face mask or helmet comprising a breathable gas supply apparatus according to the first aspect.
Preferably, the one or more valve means and face mask/helmet are so configured as to locate the one or more valve means to one or more side regions of the face mask/helmet, to reduce torque in use.
Most preferably, a first rebreather valve is configured to connect to auxiliary port 1 of a standard diving face mask or helmet, and a second rebreather valve is configured to connect to auxiliary port 2 of a standard diving face mask or helmet.
Preferably, the diving face mask or helmet comprises one or more additional auxiliary ports. Most preferably, the face mask or helmet additionally comprises a source of compressed breathable gas.
A further aspect of the invention may be provided by breathable gas supply apparatus, for connecting with a diving face mask or helmet, the gas supply apparatus is connectable with an inlet and outlet of a rebreather or reclaim unit for a first supply of breathable gas for closed-circuit use, and a supply valve for a second supply of breathable gas for open-circuit use, wherein, the apparatus comprises:
Advantageously, the proposed invention:
The following advantages are also perceived, with specific reference to a standard rebreather, and are as follows:
The invention will now be disclosed, by way of example only, with reference to the following drawings, in which:
The invention will be described in relation to a known face mask/helmet 100 which includes auxiliary connection ports 101; 102 located at side regions of the mask, a transparent view screen 103, demand valve 104, exhaust valve 105 and an internal oronasal mask 106. The face mask 100 includes one or more seals 107 for sealing to a user's head.
Auxiliary connection ports 101; 102 are normally used for a microphone or external breathing port (not shown at those locations) but, for the present invention, are repurposed for use as closed-circuit breathing connections. The demand valve 104 typically provides breathable gas from a pressurised gas supply. This supply is retained in the present invention and is used during closed-circuit use to provide top-up gas if additional volume is required or is deactivated entirely. The demand valve is otherwise only used when the closed-circuit is deactivated or sealed off, for instance on the surface, in the case of a malfunction, or during donning or doffing of the apparatus when the closed-circuit element of the system is not in operation. The exhaust valve is normally used for the ejection of exhaled gas, and is preferably placed at the base of the mask so as to also eject any liquid or water that may have entered the mask. In the present invention the exhaust valve is modified as explained below. The view screen 103 enables the user to see their surroundings underwater, and the apparatus is sealed to the user's head or neck with a seal 107. The internal oronasal mask is used to reduce the build-up and re-inhalation of carbon dioxide within the mask or helmet, and to prevent water vapour from the user's breath condensing on the view screen 103, and within the face mask as a whole. In the present invention the oronasal mask is modified as explained below.
For convenience,
The supply of compressed gas 3 is supplied with breathable gas from cylinders or tanks (not shown) which are standard and known in the art, which cylinders/tanks per se do not form part of the invention. According to the invention, the supply 3 includes a supply valve 4 (second valve means) which is operable to open and close the supply of compressed gas 3 through a reciprocating movement. The valve 4 is operably connected to the rebreather apparatus 2, as explained further below. Compressed gas is supplied directly into the face mask 100 in the region(s) of the transparent view screen 103 to help minimise fogging.
The rebreather apparatus 2 includes a rebreather/reclaim unit 5 which is capable of receiving exhaust gas from breathing and reprocessing the exhaust gas to provide breathable gas for inhalation by the user. The rebreather/reclaim unit 5 reprocesses the breathing gas by removing carbon dioxide and restoring oxygen content. The rebreather apparatus 2 further includes switch blocks 6; 7 (including rebreather valves), which are connected to auxiliary ports 101/102 of the face mask 100, and have hoses 8; 9 for transferring exhaled gas to the rebreather/reclaim unit 5 and reprocessed breathable gas back to the face mask 100. The rebreather/reclaim unit 5 is standard and known in the art.
Each switch block 6; 7 includes internal valves 10a; 10b (first valve means) and external handles 11a; 11b, respectively, operatively connected to the internal valves 10a; 10b. Each handle 11a; 11b is operable by rotation from a first condition in which the valve 10a; 10b is open to a second condition in which the valve 10a; 10b is closed, so as to open and close passageways for transmission of exhaust gas /breathable gas to/from the rebreather/reclaim unit 5. In this example, the handles 11a; 11b are rotatable through 180 degrees between first and second conditions—although this is not essential. Each switch block 6; 7 is a manually operated, airtight switching mechanism that enables switching between breathing from the rebreather/reclaim unit 5 and an optional surface air intake 25 or supply of compressed gas 3.
With respect to operation of the switch blocks 6; 7 to open and close passageways leading to the rebreather/reclaim unit 5, both operate in a similar way. However, in this example switch block 6 has additional functions—although it could be either switch block.
Each switch block 6; 7 includes a one-way valve 29 at its distal end from the face mask 100, which serves to ensure the correct direction of flow of gas around the rebreather/reclaim unit 5, but is also so located to prevent flooding of the rebreather/reclaim unit 5. As shown in
As shown in more detail in
As shown in more detail in
Switch block 6 is also operatively connected to a modified exhaust 105′ (third valve means), which has essentially the same function as a normal exhaust 105 in open-circuit use, but which, in closed-circuit use, is biased closed. The first end 13 (of linkage 12) includes a connection 21 which operatively connects the linkage 12 to a connector 22 at a first end of the connector 22a, and operatively connects a second end 22b of the connector 22 to the modified exhaust 105′, which aspect is more clearly shown in
The modified exhaust 105′ ensures that, when the exhaust valve 23 is biased closed in closed-circuit use, a greater pressure is required than provided by breathing alone to cause gas to escape and, so, gas is not unnecessarily wasted and can be reprocessed. Conversely, when the exhaust valve is unhindered in open-circuit use, exhaled gas is free to escape through the exhaust valve 23.
The breathable gas supply apparatus 1 further includes a modified oronasal mask 106′. The oronasal mask 106′ includes an inlet and an outlet 25; 26 direct from/to the switch blocks 6; 7, which are used for closed-circuit breathing. One-way valves 27 located in a nasal bridge region of the oronasal mask 106′ have the dual function of allowing compressed gas from the transparent view screen 103 into the oronasal mask 106′, and preventing exhaust gas from exiting the oronasal mask 106′ at this point. This prevents fogging and also ensures that, in open-circuit use, exhaled gas passes correctly through the exhaust valve 23 and, in closed-circuit use, exhaled gas is recirculated for reprocessing in the rebreather/reclaim unit. 5. In open-circuit use, dry breathable gas first passes across the view screen 103, causing any condensation to evaporate, before entering the oronasal cavity 106′ to be inhaled.
Switch blocks 6; 7 further include relocated auxiliary ports 30 which may be used for communications and/or drinking/feeding functions. In addition, or alternatively, one switch block includes a surface air valve 31—which is preferably designed to close underwater. This port 30 if used for communications allows cables for a microphone 32 to pass inside the mask 100, and further includes a push-to-talk button 33 and earpiece 34 allowing the diver to both talk and listen to communications via a through water communications unit. The same earpieces 34 may be optionally used to relay electronically generated messages relevant to the dive, for instance information on depth, time, gas mixture, heading, reserves of essential supplies, and system status. The invention provides the advantage that speech and verbal messages are uninterrupted by the loud noises associated with open-circuit SCUBA diving, namely the emission of compressed gas through the demand valve, and the escape of bubbles through the exhaust. Thus, far clearer communications are possible. Further, the ports 30 are configured such that any additional communications and/or drinking/feeding functions are unhindered by operation of the one or more valves.
The apparatus of the invention may include flexible or rigid hoses, or a combination thereof. In the case of the invention being a full-face mask 100, hoses 8; 9 are preferably flexible to allow movement of the head. Conversely, in the case of the invention being a helmet 100, hoses 8; 9 may be flexible or more rigid as the user may rotate its head within the helmet 100.
The position of the external handles 11a; 11b may indicate a direction to which the corresponding valve is operative. For example, and as shown in
In an alternative, switch blocks 6; 7 may be mounted directly to a face mask or helmet if auxiliary ports are unavailable or such connection is less preferred.
In use, switching between closed-circuit use and open-circuit use is easily achieved. Owing to the connections between switch block 6 and the valve 4 of the supply of compressed gas 3—through linkage 12—and between switch block 6 and the biasing plate 24 of the exhaust 105′—through connector 22—by simply turning handle 11a through 180 degrees a first rebreather valve (valve 10a for the inlet or outlet of the rebreather) is closed and, simultaneously, supply valve 4 is opened and the biasing plate 24 is moved away from the exhaust valve 23. Further, by simply turning handle 11b through 180 degrees a second rebreather valve (valve 10b for the other of the outlet or inlet of the rebreather) is closed. In these conditions of the valves, the user breathes compressed breathable gas from cylinders (not shown). As each of the handles 11a; 11b is conveniently located at a side region of the face mask/helmet 100, each can be easily operated at the same time with the user's hands.
Moreover, switching between open-circuit use and closed circuit use simply involves rotating the handles 11a; 11b in an opposite manner. This has the effect of opening both rebreather valves (valves 10a; 10b) which opens hoses 8;9 to the rebreather unit 5, optionally closes valve 4 to seal the supply of compressed gas 3, and releases biasing plate 24 to again contact the exhaust seal 23 to bias it closed. In these conditions of the valves, the user breathes reprocessed air from the rebreather unit 5.
It should be noted that the above is the preferred mode of operation, but the operation of the apparatus may be simply adapted to provide additional functionality. For example, whilst it is essential that when the rebreather is closed another supply of breathable gas is opened, that need not be compressed gas as it could be provided by a surface air valve. In addition, it is not essential that opening the rebreather necessarily seals the supply of compressed gas, as it may be preferred to top-up the rebreather and use both sources of breathable gas at the same time for a period of time.
Those skilled in the art will understand that the direction of movement of gas through the breathable gas supply apparatus 1 may be reversed without significant change to the apparatus 1. Those skilled in the art will also understand that operation of the switch blocks 6; 7 may be reversed, such that switch block 7 is operatively connected to one or more of the supply of compressed gas and/or the exhaust. Further, the apparatus may be easily modified to combine the functions of switch blocks 6 and 7 into a single operation, should this be desired.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2106379.7 | May 2021 | GB | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/GB2022/051139 | 5/4/2022 | WO |
