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Who is interested in a new kind of BCD?

Discussion in 'Research and Development' started by trash, Mar 24, 2005.

  1. Charlie99

    Charlie99 Solo Diver

    # of Dives: 500 - 999
    Location: Silicon Valley, CA / New Bedford, MA / Kihei, Maui
    7,966
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    I found a disclosure, but nothing that looked like an application. What are prior art references and your unique claims, and unique advantages?

    I recall seeing a functional equivalent thing for sale a couple of years ago. Since it was just fixed volume ballast tank, it didn't have a piston like yours, and the air bubble would change position as the diver changed attitude. Whether that's good or bad is debateable.

    Before you spend much money on a patent application, it would be wise to get info on the earlier device and find out why it flopped. There are lots of patents that don't have much value. In hindsight, most of my patents weren't worth the cost of getting them. The real trick, sometimes, is to figure which ones are worth getting.

    Charlie Allen
     
  2. Charlie99

    Charlie99 Solo Diver

    # of Dives: 500 - 999
    Location: Silicon Valley, CA / New Bedford, MA / Kihei, Maui
    7,966
    158
    63
    The real question is "why did the prior art fail in the marketplace?"

    IIRC, there was a unit out a few years ago, but it didn't ever sell much. It was a fixed volume hardshelled tank that kept the same buoyancy, independent of depth.

    My guess is that it was an expensive, complicated solution that solved only HALF of the problem. Yes, if the floatation/buoyancy control air bubble is in a hard shell, then it won't compress/expand as you change depth; but you still have to compensate for wetsuit neoprene (or drysuit air bubble) changes in buoyancy. Putting a hardshell around your buoyancy bladder might eliminate 1/2 or even 2/3 of your buoyancy changes with depth, but you still end up having to adjust.

    How much is it worth to a diver to only have to adjust his BC half as much??
     
  3. trash

    trash Angel Fish

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    Thanks but all the prior art patents I've found are now expired. The big tank BCD had problems. Half a tank of water sloshing back and forth is annoying. Air is dumped at the top and water is added at the bottom of the tank. The attitude of the diver can prevent the adjustment of buoyancy.

    I refer you to paragraph 5 of the Description where my BCD is part of a system that keeps ambient pressure air in the drysuit. http://mnav.netfirms.com/abcdm.htm#1

    To elaborate a bit, the reg is a second stage like the one in your mouth, as such there is never a pressure drop across the piston so it won't move. Going deeper just opens the reg to fill the chamber with air at ambient pressure. The opposite happens on ascent. The volume and buoyancy remain the same as you set it.

    I left out the images of the exhaust valves on the drysuit. They are one-way check valves on the top and bottom that keep the suit with minimum air, like when you are on the surface and pull your neck seal to burp the air out. A supply of ambient pressure air from my BCD keeps the suit from squeezing the diver and changing the volume of air in the suit. In other words the buoyancy of the suit also stays constant with depth.

    If the suit or undergarments are not made with closed cell foam rubber, such as a lightweight fabric drysuit, then the buoyancy of the BCD, drysuit, diver's lungs and face mask remain constant between the surface and the bottom... this is perfect buoyancy control. Only the tank's buoyancy changes throughout the dive.

    tr
     
  4. murphdivers286

    murphdivers286 Public Safety Diver

    # of Dives: 200 - 499
    Location: Port St Lucie, Florida
    3,816
    4
    38
    Sounds very interesting. I also have some invention ideas for diving. I just need to know how to patent these ideas.
     
  5. Web Monkey

    Web Monkey Omniheurist ScubaBoard Supporter

    # of Dives: I just don't log dives
    Location:
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    Not to be too negative, but you should probably just take the responses from the manufacturers at face value and not bother.

    What you have devised is a complex solution to a problem that doesn't exist.

    I really can't see how your device performs better than a standard BC, while at the same time being more complicated, and almost certainly more expensive.

    Terry
     
  6. trash

    trash Angel Fish

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    Hey Terry, I bet you drive a standard (a.k.a. Model T) transmission. Automatics are for whimps, right? :wink:

    My complex piston, cylinder, check valves, and demand regulator greatly simplifies the non-existent problem of buoyancy that seams to get mentioned in Every diving course.

    Those quotes from a couple of manufactures I gave are not their considered opinions but just lame attempts to dismiss my idea without real study. They didn't ask me a single question. They still don't know that I'm talking about descending 100 feet at a constant rate without adjustment, and then staying neutral with one adjustment until the mass of the tank drops enough to correct for it.

    Cheers man. tr
     
  7. H2Andy

    H2Andy Blue Whale

    # of Dives: 200 - 499
    Location: NE Florida
    29,646
    376
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    Trash, could you (in English) explain to me what this device does?

    (not how or why, but what it does)
     
  8. Web Monkey

    Web Monkey Omniheurist ScubaBoard Supporter

    # of Dives: I just don't log dives
    Location:
    6,921
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    If you think you can make a go of it, feel free.

    Terry
     
  9. jonnythan

    jonnythan Knight Scublar ScubaBoard Supporter

    # of Dives: 200 - 499
    Location: Upstate NY
    10,070
    109
    63
    Well..... yes, they are :wink:

    If you build a functioning prototype that actually works, they might be more interested. It doesn't sound like it will be easy to make functional.. and even less easy to make reliable, which is the #1 concern.
     
  10. donacheson

    donacheson Solo Diver

    # of Dives:
    Location: Maryland
    660
    1
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    It's going to be bulky. One has to compensate for the 5 or 6 pounds of air held in by single tank (and lost during the dive) and 15 or more pounds for wet suit compression (6mm suit taken to 100 feet). That's at least 20 pounds. Since water weighs about 1 pound per pint, the volume of the cylinder would have to be at least 10 quarts, which is approaching the size of an Al80 (11 liter) tank.
     

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