Hello Joe

I thought something like this.

Glue a PM to the 'door' and as a rubber stopper use another Permanent magne=
t
(Neo, the best) inside a non magnetic tube with a plastic or wooden piston,
glue that PM and use a spring with a screw and nut  on the opposite side of
the tube, to regulate it's force.
Not very techy but will work... may be for your application.

Cheers

Rodolfo

-----Mensaje original-----
De: piclist-bounces@mit.edu [mailto:piclist-bounces@mit.edu]En nombre de
IVP
Enviado el: Miercoles, 19 de Diciembre de 2012 02:34 a.m.
Para: Microcontroller discussion list - Public.
Asunto: Re: [EE] Electromagnet query


> Will you invert poles once the 'door' is near your EM ? Is it
> imperative to use an EM ?

Hi Rodolfo,

Simply turning off the current will make the 'door' magnet stick to
the end of the iron core. Which I think makes it and the EM a good
pair. If it was necessary to release the magnet with little or no force
(ie not manually) the current can be turned on to repel it. Still having
a think about that part of the mechanism

Joe
--
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist

--=20
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist
.