On Fri, 27 May 2016 13:50:22 -0500, Jon Elson
wrote:

Ned Simmons wrote:


I'd be reluctant to call the folks who designed the machine idiots.
Normally, yes. But, if the only way to stop the pallet is by shutting off
an AC motor and letting the whole system coast to a stop, AND it is required
that the pallet index reliably, then I'm sorry, but this was a bad design.
Certainly, if no precision was needed, it would be fine. If precision
indexing was desired, then even in 1960, the technology was available.

You could use a shot pin, as you say, or a hydraulic valve that would stop
the hydraulic motor much more rapidly than the coasting motor. Or, a Geneva
mechanism to advance the pallets and index them, and a small coast of the
hydraulic motor would not cause the pallet to move. So, there were lost of
WELL-KNOWN techniques that were in widespread use much more than 50 years
ago.

Jon

Well stated.