Re: re:RE: Ballscrews/linear drive

--- In CAD_CAM_EDM_DRO@egroups.com, ballendo@y... wrote:

> Steve G wrote:
> > The other option I'm considering is something I found in the Small
> >Parts Inc. catalog. I can't locate my catalog to get the name of

it,

> >but it > sort of "climbs" a smooth rod as though it were a
> >ballscrew. Anyone know what I'm talking about?
>
> Sure do! This would not be a good choice, IMO. It could be made such
> that the "rollers" are 'lift-able', in the event of power outage.
> Then it might be OK.

The ones I've seen don't seem to have this ability. I hesitate to rely
on the slip of these to allow the doors to be forced open. The client
had originally suggested some kind of door to open to pull a rope to
turn the screw, but my instinct tells me that in an emergency
situation where people just want to get out (smoke and fire, for
example) -their- instinct is going to be to force the door, not stand
there looking for instructions and a panel to open. Same goes for
having some sort of handwheel, even out in the open.

How do they do this on automatic sliding doors? They seem to just slip
if you force them apart, albeit with great difficulty.

> > Any help is appreciated. Especially names of suppliers in the
> > Tacoma/Seattle area, places that don't have a "3 question
> limit". :')
>
> Seems like some trim or flap actuators from Boeing surplus might be
> just the ticket...

Oh, sure, then the door crashes, and then where am I at. ;') That does
sound like they'd work, but I'd have to find two. What does something
like that usually go for from Boeing Surplus? Anybody?

> Hope this helps.

Yes! Just knowing that the correct name of the assembly is in itself a
big help.

Steve "Newbie" Greenfield