--
Christopher A. Young
Learn more about Jesus
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"Ignoramus4694" <ignora...@NOSPAM.4694.invalid> wrote in
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news:mOidndAKLeUwGl_W...@giganews.com...
http://igor.chudov.com/tmp/Winch/
My inclination is to think that it wasn't built for "general" pulling or
lifting, but make to lift a particular something like, perhaps, a well
drilling derrick. Even though there's a fair amount of rope on the drums,
they're not very deep, indicating to me that they were designed for a
fairly short haul.
The worm gear arrangement requires that it be operated in power-up/power-
down manner; it won't free-wheel when the clutch is released.
LLoyd
This is supposedly for electricians to pull cables underground.
> The worm gear arrangement requires that it be operated in power-up/power-
> down manner; it won't free-wheel when the clutch is released.
that's what I thought, sans the note abouit vibration, thanks
That application makes some sense as it isn't a real drum winch but
rather some cable drums grafted onto a double right angle gear reducer.
A real drum winch would have both ends of the drum supported and a
really high gear ratio. Despite the cable installed on one side, I
expect this was used more as a capstan winch for continuous pulling.
Many utility trucks I've seen have a similar hydraulic capstan winch
mounted on them.
(...)
> The worm gear arrangement requires that it be operated in power-up/power-
> down manner; it won't free-wheel when the clutch is released.
The band brake appears to release when the motor is
powered, so *someone* thought it might free wheel.
--Winston
Or it could be to get the drums to stop quickly after the motor stops
(crude positioning).
Dave
> Despite the cable installed on one side, I
> expect this was used more as a capstan winch for continuous pulling.
> Many utility trucks I've seen have a similar hydraulic capstan winch
> mounted on them.
>
>
I sort of thought that, too; that it was a capstan. But the tag hole in
the drum indicates the cable was intended to terminate at the drum, rather
than just being wrapped a couple of turns.
LLoyd
> The band brake appears to release when the motor is
> powered, so *someone* thought it might free wheel.
>
Nah... that's just to quickly stop the drums, rather than having the motor
"wind down" and pull a couple more feet after the off command.
With a worm drive, it ain't free-wheelin' _anywhere_.
LLoyd
I do not think that it is a capstan.
>
> I sort of thought that, too; that it was a capstan. But the tag hole in
> the drum indicates the cable was intended to terminate at the drum, rather
> than just being wrapped a couple of turns.
The cables are terminated at the drum indeed and need to be cut to be
taken out.
i
Or it could be to get the drums to stop quickly after the motor stops
(crude positioning).
Dave
We are in violent agreement, Dave and Lloyd.
"FREE-WHEELING: In reference to rolls, spinning without the application of
either driving or braking force."
I warn't talking about 'back driving'. That's similar to the way a
music box 'inhibitor' or speed regulator works and ain't gonna happen
for any reasonable gear ratio of worm drive for motor use.
Himfella anti-freewheeling brake.
--Winston
Hey Iggy,
I am getting into this a bit late, and assuming this your thread.
I could see this having a "load" on one side and a counterweight on
the other. I can't tell from the pix, but if the brake is lifted and
the motor shaft is turned, does one drum "wind on" while the other
"winds off"?? Some dumbwaiters work like that.
Brian Lawson.