In article . com,
Robatoy wrote:
On Oct 23, 8:04 pm, (Doug Miller) wrote:
In article , Tom Veatch wrote:

missed the planetary gear direction, matching up the description
(reverse, reduction, etc.) with the gear pictures, and the fan blowing
on the fan.

The fan blowing on the fan is an ambiguous question. They're facing each
other, and spinning the "same" direction, in the sense that when viewed from
the side, they're both spinning down on the edge facing you (or up, depending
on which side you're on). But when each one is viewed from *its*own* front,
one is spinning clockwise, and the other counterclockwise.

So is that the same direction? Or the opposite direction?

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

Both blades rotate in the same direction regardless of vantage point.
You stand behind one fan, and both blades turn clockwise. You stand
behind the other, both blades turn anti-clockwise. What on earth is so
hard about that, oh wise one?


It's a matter of viewpoint. the question is BADLY worded.

If both fans were turning in the 'same' direction,, both would be pushing
air from back-to-front of the fan.

one fan is turning 'forwards' the air is travelling from back to front
of that fan.

The other fan is turning 'backwards' the air is traelling from front to
back of thhat fan.

Considered from a single external viewpoint, both are rotati in the same
diretion.

Considered from the view point of the motor on each fan, for _that_
fan, they are rotatig in different diretion.

The issue is whether the fan 'reverses diretion of rotation' just beause
you point it in a different diretion.

*GENERALLY* shaft rotation is measured relative to the motor, indepedant
of absolut orientation in space.