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Large flapping vanes with ratchets, sprockets, chains, and a generator
Consider a ratchet wrench --or, rather, the ratchet mechanism
that give it its name. When the handle is oscillated, the
turns an axle in just one direction.
Suppose that handle was a vane with significant surface area.
placed in an airstream such as the wind, the typical vane
indicates wind-direction. That's because the vane is usually
oriented horizontally. But if it was mounted vertically, with an
axle along the long edge of the vane, it might flap in the wind.
Let's start with a 1-meter-long vertical axle. We place ratchets
at the top and bottom of the axle, and a vane fits between
them, extending from the
axle for only 5 centimeters or so (it is not quite 1 meter tall).
vane flaps in the wind, the axle is forced to rotate in only one
direction. An extension of the axle could be the shaft of a
As a bonus, because we are talking about two ratchets, one of
them could be connected with a reversing gear to the axle.
That way, whichever way the vane flaps, it applies rotational
force to the axle, always in the same direction.
We now note that our nearly-1-meter-tall vane has two long
edges. There is an axle along one edge, and now we want to put
another axle along the other edge. Since the axle is 1 meter
and the vane is a little shorter than that, part of the axle
above and below the vane. We mount "ratcheted sprockets" on
axle at those locations, on BOTH axles. We connect them with
standard drive-chains, like a bicycle has.
Next, we add another vane. Think of that second axle as being
like a hinge-pin, and the two flat portions of a typical hinge are
the vanes. So, starting at the generator-axle, it is connected
ratchet mechanism to the first vane, and that is connected to
another vane with a hinge-pin axle. However, this vane can
independently of the first vane, and when it flaps, it drives the
ratcheted sprockets, which move the chain and help drive the
We can now add another axle to the second long edge of the
second vane, with more ratcheted sprockets, and a third vane.
The second axle will actually have 4 sprockets on it, 2 above
vane and 2 below it. Of each pair, one sprocket connects with
a chain to
the first axle, and the other connects with a chain to the third
axle. All three vanes can now flap independently of each other,
and all contribute to sending mechanical force to the
generator axle, thanks to the ratchets.
We can now extend the preceding with several more axles and
vanes. At 5 centimeters per vane, if we had 30 of them the
total extension from the first axle would be about 1 and
1/2 meters. The overall device has roughly the proportions of
the average national flag. We can now paint it to look like an
ordinary cloth flag. It flaps in the wind like a cloth flag, too**.
And it generates power
whenever it flaps. It might even flap in light breezes, because
it doesn't sag like a cloth flag.
**Well, actually, the more mass is associated with this device,
the less it will flap. Perhaps the vanes need to be frameworks
with sailcloth stretched across the space inside the frames.
And that 1-meter-by-1.5-meter description could be greatly
enlarged, so the "flag" is huge, but interacts with as much wind
Both ways ratchet
It appears I'm not the only one who could use such a device, although the description in the main text here talks about two ordinary ratchets, one of them associated with a reversing gear. One-OR-the-other ratchet goes click-click-click when the vane flaps, while the one that isn't clicking uselessly is applying force to the generator axle, always in the same direction. All the other ratchet-driven axles can have that feature, too. [Vernon, Mar 28 2015]
Both ways screwdriver
Double-ratcheting tech does exist and does work [Vernon, Jan 07 2017]
Prior art. Basically this, but anchored at both ends. [notexactly, Jan 09 2017]
||Normally, when you're trying to capture wind energy, you set up a windmill, which, so to speak, tries to stay pointed towards the wind.
||It looks as though you're trying to capture wind energy from a weather-vane, which, so to speak, tries to stay as far as possible out of the wind.
||A windmill says to the wind, "Oi, in your face; where do you think you're going with that energy? I'll have that, thank you very much!". A weather vane says, "Oops, sorry, am I in your way? Don't mind me - I'll just go over here, and then you can get past".
||This idea is like a weather vane with an attitude problem, that occasionally tries to trip up the wind or pick its pocket in passing, but has very limited ambitions. Or have I misunderstood it?
||[pertinax], it takes energy to cause a flag to flap in the
wind. This Idea is about capturing that flapping-energy.
Yes, I know it can't be a lot, and I know the device is
probably excessively complex, but I also know this is the
||A note on adding a reversing gear to a ratchet-driven
axle: Here is an ASCII sketch (axle is horizontal and has
The "D" "V" and "C" are all bevel gears (the axle of the
"V" gear, not shown, is perpendicular to the other axle).
The two segments of the overall/shown axle will rotate
in opposite directions.
||Therefore one of the two axle-segments can be ratchet-
driven by a particular oscillation-direction, and the
other axle-segment can be ratchet-driven by the
opposite oscillation-direction. A generator attached to
either axle will always receive force from either
||// This idea is like a weather vane with an attitude
||Could be done with water in pipes, non-return valves and so on.
||Wind send ripples down the flag, which compress part of the pipe, so pumping water about.
||Or magnetically - flag has lots of rods 90 degrees to the surface of the flag, the rods have magnets on them, which sit in coils etc would work best with segmented flag.