On 6/28/07, Cedric Chang <cc@nope9.com> wrote:
>
> > On Jun 27, 2007, at 10:06 PM, Vasile Surducan wrote:
> >
> > The key is not only the winding number/cross section (which is a
> > problem of mechanical power versus efficiency) but the presence
> > of the magnetic flux amplifier (brass tube as a support for
> > windigs) and
> > an end of the slug made from brass with a cone shape and perfect
> > match into the
> > negative cone of the ending brass tube.
> >
> > Inspire yourself from a high power DC relay design. The efficiency of
> > such construct is huge compared with a poor iron slug.
> >
> > Vasile
> >
> Why brass ?

Because it concentrate the magnetic field.


> Cedric
> >
> > On 6/27/07, Cedric Chang <cc@nope9.com> wrote:
> >> I am rewinding a solenoid for the fuel control on a truck injector
> >> system.
> >> A slug that is restrained by a small spring is pulled into the
> >> solenoid to allow fuel to flow.
> >>
> >> Since I have a fixed amount of space, I am wondering if it
> >> is better to have many windings of a smaller gauge wire or
> >> fewer windings of a larger gauge wire.  I am not worried about
> >> inductance or ease of winding.
> >>
> >> I am seeking the optimum tradeoff between heat dissipated
> >> by the coil and maximum magnetic field inside the solenoid.
> >>
> >> I am guessing that the amount of heat dissipated is inversely
> >> related to the square of the diameter of the wire ( holding
> >> everything else constant ).
> >>
> >> The B-field seems as though it would also be related to the
> >> inverse of the square of the wire diameter.  ( divide the diameter
> >> by two and get 4 times as many windings. )
> >>
> >> If I keep everything constant except I vary the current through the
> >> solenoid, the B-field seems to vary linearly with the current while
> >> the heat dissipated by the solenoid seems to vary the square
> >> of the current.  Would this suggest that lowering the current and
> >> increasing the number of windings would improve the solenoid
> >> capabilities.
> >>
> >> I feel I have made a mistake here somewhere since a gazillion
> >> windings and nearly zero current would give me the magnetic
> >> field I want.
> >>
> >> Of course there must be some amount of energy required to
> >> move the slug into the solenoid.
> >>
> >>
> >> --
> >> http://www.piclist.com PIC/SX FAQ & list archive
> >> View/change your membership options at
> >> http://mailman.mit.edu/mailman/listinfo/piclist
> >>
> > --
> > http://www.piclist.com PIC/SX FAQ & list archive
> > View/change your membership options at
> > http://mailman.mit.edu/mailman/listinfo/piclist
> >
> --
> http://www.piclist.com PIC/SX FAQ & list archive
> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist
>
-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist