Loading ...
Sorry, an error occurred while loading the content.

1667Re: Greetings, and extrusion

Expand Messages
  • ttelmah
    Feb 1, 2011
    • 0 Attachment
      --- In diy_3d_printing_and_fabrication@yahoogroups.com, Lino <creaturemaker@...> wrote:
      >
      > screw pump
      >
      > http://upload.wikimedia.org/wikipedia/commons/d/d8/Screw_pump.png
      >
      >
      >
      > On Mon, 31 Jan 2011 19:08:53 -0800, Jon Elson <elson@...>
      > wrote:
      >
      > >
      > > Fernando wrote:
      > > >
      > > >
      > > > Is that as in one screw feeding the other from a vat?
      > > > How would that be mounted, at a 90º angle to eachother?
      > > No, one is left-hand, one is right-hand, they lie parallel andinterlock,
      > > in a housing with a figure-eight cross-section.
      > > They rotate in opposite directions.
      > > This pinches off regions in the outer part of each screw, while the
      > > overlap prevents any flow
      > > backwards. Each pinched-off region moves from the inlet side to the
      > > outlet side.
      > >
      > > See http://impeller.net/magazine/news_en/doc3413x.asp for a mediocre
      > > picture, but the best one
      > > I could find.
      > >
      > > Unlike an Archimedes screw, these are positive displacement pumps, they
      > > can stop and the fluid
      > > will not flow backwards.
      > >
      > > Jon
      > >
      >
      >
      >
      > --
      > Using Opera's revolutionary email client: http://www.opera.com/mail/
      >
      It's funny, but another posted has talked about a two helix design, the Wikipedia article shows a three helix design.

      Mono, do a two 'rotor' design, but it is not the pump I remember, which is like a spiral version of the same idea. It has now 'got me annoyed', since I used one of these something like forty years ago, submerged in a well. I'm sure the name was pronounced like 'mono', but was a couple of characters longer...

      I suspect all these designs would be too complex, and think peristaltic, with a stepper and a bit of 'intelligence' to give automatic drip control, may be the nicest solution in terms of easy maintenance, reasonably low cost, and achieving the required operation.

      Have to sit down and think if the basic parts for this could be extruded in ABS, if so will have to build an extrusion head for this (thousands of designs for this online), and try this as an 'intro' experiment, to see how things go.

      Off to do some drawing/thinking again.

      Best Wishes
    • Show all 20 messages in this topic