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Clockwork lawnmower   (+5, -1)  [vote for, against]
Clockwork powered lawnmower

I don't have a large enough garden to warrant owning an expensive (and noisy) petrol or electric-powered lawnmower, and anyway, I don't like the trailing flex that electric-powered lawnmowers have. On the other hand, I like manual lawnmowers (you push it along; the blades go round), but they're hard to push through long grass. The solution: a clockwork lawnmower: A really tough spring stores energy which drives a clockwork mechanism which makes the blades go round (you still have to push the lawnmower). "But", I hear you say, "such a spring would be hard to wind up!". Don't worry, the clockwork lawnmower has a simple winding key which can be wound by any electric drill.
-- hippo, May 10 2000

(?) For safety's sake http://www.halfbake...ea/Baby_27s_20Blood
[scubadooper, Oct 05 2004, last modified Oct 17 2004]

It would take quite a long time for an electric drill to wind a spring like that enough to mow a lawn. In essence the drill would indirectly supply the power to turn the blades. It just wouldn't be worth the trouble or time.
-- dontthink, May 10 2000


What if the pushing of the mower wound the spring rather than turning the blade, and then the spring turned the blade? Have the wheels ratchet the spring until it can't take any more winding.

Net effect - the spring acts as a battery for the force that you supply at a constant pushing-the-mower rate, which would let the spring do the tough work of cutting the long grass.

It would probably make sense to have a hand control to control a clutch to start and stop the blade, too, so you could wind the spring by pushing the mower from your shed to the front lawn without wasting any of the precious windings.
-- tomierna, May 11 2000


According to some on rec.antiques.radio+phono, old Victrola windup record player motors were used as trawling motors on fishing boats sometimes. Apparently they stored an incredible amount of energy. Use a long armed crank instead of an electric drill, and maybe have the wheels able to wind the spring as well.
-- StarChaser, May 11 2000


Yea. Use the leverage of a long arm to provide extra power instead of back-breaking push mower work. Actually, mowing the lawn isn't really that tough, but I think I'm too young to complain. <grin>
-- dontthink, May 12 2000


I like the idea, it would also be much more asethetically pleasing to look at. I love clockwork crap.
-- andre3731, Mar 08 2001


For safety's sake, all the moving parts would have to be painted orange. [the joke light is: <on>]
-- absterge, Mar 08 2001, last modified Mar 09 2001


How about not having a lawn at all? There are other, maintenance-free ground covers.
-- mrthingy, Mar 09 2001


Buy a goat. It you have a really small lawn, buy a really small goat.
More seriously, but only just, I know of someone who leases out his goat to the authorities in his home village. The council gets cheap grass-cutting, the goat gets free food.
-- angel, Apr 27 2001


Does he do this so he is able to say that the local authorities have really gotten his goat this time?
-- Aristotle, Apr 27 2001


Buy a cordless electric mower. It won't be any noisier than an electric drill.
-- redpony, Apr 28 2001


A while ago I had to mow the lawn with a push mower that had blades that were as sharp as a hot stick of butter. Needless (or is that needles?) to say, it would be great to have a non-governed spring motor that would only be used when the grass wound around the blades (the blades wound around the blades?). You could mow the lawn normally, then when the mower gets stuck, you could turn a crank, and then press a button and the spring would unleash itself on the grass.
-- Amishman35, May 10 2002


Why don't you just nix the batteries, springs and drills. Gear the drive to the blade to make it feel like you aren't pushing it through tall grass, but still cut. This wouldn't be constant motion, but it would make it easier, cheaper, and quieter than a drill, spring or batteries. As the size of the gears change the ratio of the outcome changes as well.
-- cprdnick, May 14 2003


[hip] You're on the verge of a croissantable idea here. Just get rid of the clockwork. Make this "Lawnmower Cordless Drill Attachment" (" Yay!"?) and I'll vote for it. Why spend time winding a spring with your drill when you can be powering the thing with your drill as you mow. Plus, you have the added benefit of having the largest cordless drill attachment ever created.
-- Worldgineer, May 14 2003


[cprdnick] If you do that the blade doesn't rotate fast enough.

How about painting the moving parts in baby blood (see link) for safeties sake (I'm sorry, I know it's sick but it had to be said, and yes the joke light is:<on>)
-- scubadooper, May 14 2003


Surely a pedal-powered mower would be quite bakeable (though splendidly slow).
-- friendlyfire, May 14 2003


What about a pull back to wind mechanism like in toy cars. The first push is the hardest, but then you pull back (wind the spring), set a new line and then get a spring powered assist on your next push.
-- wuss, Sep 01 2007


a small compressed air energy storage system may be superior to a metal spring (weight/energy density, simplified power modulation).

it could be charged using your drill idea, a petrol station air compressor (partly), a dedicated charger etc. all depends on what rate of charge you'd like.

a mower like this could be made very compact indeed - use the tubular frame as an air tank (and have an auxiliary input). its high surface area to volume ratio will mean efficient ambient energy absorption during operation, and provide the user with a refreshingly cool place to grip.

if i didn't live in a skycave, i'd want one!
-- TIB, Sep 01 2007



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