4 Apr
2005
4 Apr
'05
1:38 a.m.
Tony Duell wrote:
Yes, I was thinking of things like full-height 5.25" units. Larger
drives often had AC spindle motors which would clearly be unsuitable for
this trick (well, at least not simply...)
-tony
I remember seeing bits of what were apparently a Wang disk drive lying
around a mate's workshop. It had a very funky head retract mechanism,
with an interlock that held everything in place with the heads
retracted, a solenoid that pulled in on power good (and dropped out on
power fail), and a big spring with an air piston, like an air rifle,
that was fired when the solenoid dropped out with the heads extended,
blowing a ram on the positioner assembly all the way back.
Once this had happened, you needed to open the cover and re-cock the spring.
Gordon.
Didn't some winchesters use the spindle motor as a
generator to provide
the emergency retraction current?
The drives used in PC do that and have for many years but I never saw a
mainframe disk drive that did.