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03-25-2020, 08:30 PM | #46 |
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Re: Full face snorkels
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06-30-2020, 07:41 PM | #47 |
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Re: Full face snorkels
Ocean Reef’s Aria Full-Face Mask Approved As PPE For COVID-19 Treatment. “Our ARIA masks, equipped with patent pending APA adaptor and P3 filter (EN149 certified) are officially temporarily CE marked as PPEs for the protection of nose, mouth and eyes. This event crowns a big effort from our Company to achieve official recognition for the product as a PPE according to guidelines of EN136 for protection from COVID-19.” https://oceanreefgroup.com/covid19/ |
06-18-2022, 09:55 PM | #48 |
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Re: Full face snorkels
A good review article worth reading completely.
https://www.tropicalsnorkeling.com/f...rkel-mask.html A mask with a fan motor that shows how crazy some designers are to find a point of difference. https://ninjashark.com.au/collection...orkelling-mask |
06-20-2022, 09:26 PM | #49 | |
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Re: Full face snorkels
Quote:
https://www.alibaba.com/product-deta...232401656.html |
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06-21-2022, 12:55 AM | #50 |
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Re: Full face snorkels
There are many full face snorkel mask patents, some covering the ornamental or external appearance and others the technical features and internal structural variations, but I eventually found ones that related to an electric fan built into the device for assisting with the airflow. These Chinese patents belong to the Dong Guan City Blue Dolphin Sporting Goods Company Limited and the inventor is cited as Lixiang Liao.
There are two Chinese patents CN201910044057.4 dated January 27 2019 and CN201910484297.6 dated June 5 2019 and these have been followed by US patents US20200231260 A1 dated October 30 2019 and US11097818 B2 also dated October 30 2019. Note that these dates are the filing dates which establish the invention priority, not the patent publication dates which are somewhat later. Patents are also taken out in other jurisdictions to protect the intellectual property in those countries. Note that issuing of patents does not mean that they are being granted a tick of approval, they just register a claim to the idea as to who came up with it first. |
06-21-2022, 11:07 PM | #51 |
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Re: Full face snorkels
Here is the schematic for one embodiment annotated after reading through the patent text. This version pipes both inlet and outlet air via the snorkel tube, other designs can push exhaust air out via the front of the mask, but the current mask seems to be as the one shown here with an inlet and outlet at the top of the snorkel. The electric fan works on the exhaust side, but any depression created inside the mask is claimed to draw air in from the environment. Basically this mask is using electric fan assist to get around the small bore of the air ducts that hamper these devices, a problem created by trying to use a full face mask with an ambient air supply in the first place. Check valves co-ordinate air movement and shuts things off if water penetrates the float chambers in the snorkel top to cut the power and stop water entering the mask, or at least they do on paper and with everything working properly.
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06-22-2022, 08:58 PM | #52 |
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Re: Full face snorkels
The largest drawback with full face snorkel masks is you have a big air bubble strapped to your face which, unlike a conventional snorkel, you have no mouthpiece to spit out if you find yourself in any sort of breathing trouble. To achieve a reliable seal on your face these gadgets have a multi-strap system to anchor the mask firmly on your head that makes it much harder to rip the mask off in an emergency. The pool of air inside these full face masks is subject to turbulence when you breathe in and out and the large interior volume acts as a big mixing chamber for incoming and exhaust air. This can eventually create a carbon dioxide build-up as some exhaled air always stays in the mask as the air outlet is too small to allow a complete air exchange within the spacious interior of the mask body.
The modern full face masks are multi-component due to the elaborate shapes that can be created using injection mouldings which would not have been possible in earlier times and have the added advantage of being relatively lightweight while offering a wider transparency with their extremely large lenses. This wide open bay window feeling is probably the reason for the popularity of these masks, plus they have a space-age appearance that is very similar to what one sees in science fiction movies, particularly with the curved “bubble” lens early versions of these masks before concerns about image distortion underwater prompted the move to flat section lenses. In order to overcome the mixing of incoming air and exhaust air mentioned earlier these masks resorted to an oro-nasal section separate to the observation section that it sits inside. The idea was that air drawn in through the top mounted snorkel would flow into the observation section and then pass through one-way mushroom valves into the oro-nasal section, but exhaled air could not pass back through the mushroom valves into the observation section going the other way. Instead it could flow out through another mushroom valve at the base of the mask into the water (which also served as a drain or water dump valve) or via another flow path built into the mask’s outer frame and moving up and out on either side of the mask. However not all these masks have this separate outlet ducting and in any case the separation of airflows does not occur in practice due to leaks and poor sealing on the face and in the silicone plastic mushroom valves. Anything selling for as low as 30 dollars is not going to be a precision instrument and in many cases these masks are slapped together as fast as possible by workers trying to churn out so many per shift. The problem with all these elaborate looking masks is the bore sizes of the air ducting pipes or channels are too small, they are generally much smaller than the snorkel bores used in snorkel masks that only covered the eyes and nose in the rubber body dive mask era and they are not of a constant diameter. With the latter you could always poke you head out of the water and breathe through your mouth, but no such option exists with these modern day full face snorkel masks. Unfortunately unlike the air flow path arrows illustrating how these masks are meant to work in their adverts the airflow achieved is not the discrete stream flows that these diagrams would suggest. Instead air swirls around passing through any available gaps and cracks and in many cases the user is trying to breathe through what is not much larger than a jumbo sized drinking straw. Under any stress the air delivered is going to be insufficient to meet the user's demands. The user is restricted to head up positioning as the snorkel valves are meant to cope with the odd wave or dip of the head, not a submergence of any duration, plus they are just too buoyant for that type of service, provided they have not filled up with water! By way of comparison a conventional mask and snorkel allows the user to adopt any orientation underwater, including turning somersaults if so inclined, whereas full face snorkel masks require a definite up and down. |
06-24-2022, 10:59 PM | #53 |
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Re: Full face snorkels
Diving pioneer Commandant Yves Le Prieur patented a full face mask for snorkelling at the surface and shooting fish below with his rollerspear. Le Prieur was also involved with air supplied deep diving using commercial equipment of his devising, but this mask is not designed for submerging and the multiple snorkels have no water shut-off valves, although there are flow directing valves inside the mask. So even back then attention was paid to having large snorkel bores, something that modern designers seem to have forgotten. Few would want to dive with this monster on your head, but one has to remember when this was designed there was nothing else except modified firefighters' anti-smoke goggles and Alexandre Kramarenko’s patented mono-goggle.
Le Prieur designed this mask as a form of underwater observation chamber for swimmers, in fact he made the comment that the air capacity of the mask could support the head of the swimmer in the manner of a salvage buoy (!), so the mask was not for diving down. It is a variation on the ideas for his free flow air scuba or "scaphandre" mask. The snorkels have one way valves where they enter the mask (clapets 11) which only allow air in, not out. Exhaust air was via the lift off of the flexible side flanges of the mask skirt, a method borrowed from his air cylinder suppied scuba mask, or via a separate valve 16 in the side of the mask. Any water that seeped into the mask was pumped out via a small bulb operated hand pump 13 that would be at the low point of a mask looking downwards. At the time of his invention in 1938 there were only underwater goggles and Kramarenko's monogoggle which was designed to make use of his 1937 spring gun. Last edited by popgun pete; 06-26-2022 at 11:07 PM. Reason: more info, numbers refer to items on the patent diagram |
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