On 2013-10-10, Larry Jaques <
lja...@invalid.diversifycomm.com> wrote:
> On 10 Oct 2013 04:13:37 GMT, "DoN. Nichols" <
BPdnic...@d-and-d.com>
> wrote:
>
>>On 2013-10-09, Tom Gardner <Mars@Tacks> wrote:
>>
>> [ ... ]
>>
>>> Time delay pneumatic relays, I'm not sure exactly what you call them.
>>
>> Dashpots.
>
> Are those the same as they had on '50s and '60s auto carburetors?
> (That word brought back some deep old memories.)
Depends on the carb, I suspect. The SU carbs for my MGA had
dashpots to control how rapidly the venturi throat opened. It allowed
it to close quite rapidly.
> Are the valved mechanisms which slow metal bandsaws during cutting
> called dashpots, too? Or is there another name for those?
I don't know at all for that. The only bandsaws which I have
experience with either have only step belt speed changes (the infamous
"$200.00 horizontal/vertical bandsaw" sometimes sold for a lot less, and
the three-wheel Emco one which I have), or the DoAll which we had at
work with a variable speed pulley assembly, plus a gearbox to give a
high range or a slow range. No dashpots involved in any of those as far
as I know.
Mostly -- a dashpot is a cylinder with a very close fitting
piston (often glass cylinder and graphite piston) with an adjustable
needle valve to control how rapidly it could move. Could have an oil,
or air as the medium. Then it is up to who put it in what as to whether
it controls valves, limit switches, or whatever else. I could even
imagine them being used in some record turntables to avoid rapidly
dropping the stylus (needle) onto the record, possibly damaging both.)
I've seen at least one model of turntable which has an arc support bar,
and a lever which starts it lowering slowly, or lifts it to a safe
height and keeps it there.