Would These Designs Work?

[emperor_james]

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Image not to scale :;):

I am wondering if this design for a water gun would work. It uses a spring to create the pressure, and the design uses a regular super soaker water pump, like that found in CPS and guns with sepperate firing chambers. The red line represents a piece attached to the spring that seals that area and slides back and forth with the spring. It works much like a CPS gun, except that the pressure is created by the spring's compression. When water is pumped, it pushes the piece represented by the red line back, compressing the spring. Then, when the trigger valve (I didn't bother drawing it in the picture) is opened, the spring should push the water out. It should, therefore, have about the same consistency, since like on CPS guns the amount of water pressurized should increase proportionately to the amount of pressure generated. The effeciency of pumping would probably not be that great, due to the friction crated by the pump seal, and it is likely that the seal on the spring would leak. However, I beleive that the Water Wariors Pre-Chargers actually have something of the sort, except that they rely on air compression rather than spring compression.


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Again, image not to scale

This is another idea, similar in design to a spring powered Airsoft gun. It is also somewhat like piston pressure soakers. It works by pulling water into the firing chamber, rather than pumping it in. A small line is cut into the firing chamber to allow the handle to stick out and be pulled back. Though this would require great streangth, it would be interesting to have a sniper rifle that worked on this design.

These are just ideas, and are most likely inefficient or companies would already have utilized them. Also, it would probably be difficult to make a homemade one out of PVC, although perhaps one of the Water Warriors Prechargers could be changed into one. If this has been suggested before by someone else, I apologize, though I could not find anything like it in the Tech sections of various forums.

[isoaker]

Side note: what you labelled as 'check valves' are really just one-way valves.

The spring idea has been floating around. The general concept behind your sketches are valid. The problem really is finding a spring strong enough to be able to push out a good volume of water over a decent distance. One also needs to avoid using springs that may rust since they are likely to get exposed to moisture. I believe it is the problem with finding a workable spring which has prevented the development of a larger spring-based soaker. (The Waterball devices use springs to launch their water balls, but the output and range is very limited).

[emperor_james]

PVC pipe one way valves are called check valves though, aren't they?

Hmmm, I've forgotten a lot about metal that I knew, but it seems like you could galvanize spring steel, or mix some zinc into it like stainless steel. I really don't see what the problem about finding a strong enough spring is though, I'm sure a company such as Hasbro or Buzz Bee Toys would have no trouble finding a supplier of springs for their guns.

[isoaker]

PVC pipe one way valves are called check valves though, aren't they?

...and they are.. silly me. I'm stuck in bad terminology when it comes to valves.

As for the spring problem, if a strong spring weren't too hard to find, there should have been a spring-based soaker on the market by now. Perhaps there are also other technical problems in actually building a spring-based soaker on a larger scale. One thing I can think of is spring memory issues. For the spring blaster to work well, the spring should still be slightly compressed even when there is no water in the firing chamber, otherwise it wouldn't do a good job at pushing out the latter bits of water. However, leaving a spring partially compressed for long periods leaves the metal stressed and it will slowly lose its springiness. Perhaps also in testing, it was found that spring-based soakers work only marginally better (or worse) than air-pressure or CPS-based systems. If that's the case, then there would be no reason to build a spring-based soaker when others work as well or better without needing the additional bit of metal or reinforcing.

[emperor_james]

If you have a strong enough spring, then you shouldn't actually have that problem, at least not any more pronounced than on CPS soakers. Theoretically, anyway. Perhaps you're right; it is doubtful that springs would not be used if they are not sigificantly better. The only advantage seems to be that it would be easier to fit into a smaller gun than CPS, and be easily upgradeable.