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Washing machines are heavy. Why? Simply
because if they weren't heavy enough, the
spin cycle would cause the whole thing to
I was just leaning against my washing
machine just a minute ago, but only
because I had to. It dances when it spins,
and that pulls the drain
hose out, making
a mess if I'm not there to lean against my
washing machine to absorb the horrible
oscillations that very often occur.
Shouldn't washing machines be smarter by
now? If were thinking about RFID in our
clothes, shouldn't we have already thought
out this problem?
Our washing machines need not be as
heavy and stupid as they are. Just as
ballast has been used for centuries to
keep boats centered and level, it can also
be used to keep your washing machine
from dancing and creating havoc.
A large disc, the diameter of the inside of
the washing machine spins with your
laundry. It is maybe a couple of inches
thick, depending on how much ballast you
need. The inside of this disc is broken
into 6 different sections, which, while in
the spin cycle, can be individually filled
with water or have water released, to
counter the effects of an uneven load.
When the wash is done, the water drains
out with the rest of the water, waiting to
be filled up with next load's water.
It will be lighter to move, but it will have
more moving parts, but it all depends on
what you like less, a dancing washing
machine that sometimes doesn't complete
your spin cycle or floods your floor with
laudry water, or a service man at your
place, fixing another piece of the washing
||If you actually open your washing machine, you will find that much of the weight of it is down to a rather substantial concrete brick. Although, to be honest, this static piece of ballast is just being used to stop your machine from dancing it's way around your floor when it's on spin.
||If you grab the drum of your washing machine - no, not now, wait until it's stopped and empty - and pull it about, you'll find that it is very free to move. What actually happens when it's spinning is that the drum centres its spin axis so that it passes through the centre of mass of the drum and contents. That is, it naturally does what you are trying to achieve with a control system. Don't ask me for the maths of how it works, but believe me, if it didn't then that block of concrete would be insufficient to stop it leaping around and demolishing your house.
||Obviously however, it is not working as well as it might in your case...
||An alternative would be to bolt the machine to the floor, or possibly to increase the weight of the machine so much that a few pounds of off-center laundry would be insignificant, like an extra deck chair on the QE2.
||//An alternative would be to bolt the machine to the floor//
They do this to really high speed centrifuges. Doesn't always stop them from ripping the bolts out when somebody mis-loads one.
||I think an active damper would be a great idea. It shouldn't be terribly difficult or expensive to implement, and would be very effective.
||There are a ton of appliances that can get
many kinds of smart upgrades but why
would they do that? If you can get
consumers to buy 5 successive washing
machines by introducing small changes
over time, why do it all at once if that's
going to lose them money, even if it is
easily within their ability to do. We all talk
about the things they can do. Some are
crazy, but many are things they can
||I fear a conservationist movement would catch on to your scheme to use extra water and scuttle your plans.
||It wouldn't use extra water. It is used only
the spin cycle so it would use the water
that drains out before the spin cycle. I
though about using weights, but the
thought of using mechanics didn't seem
smart to me. The thought of something
heavy, spinning at high speeds, sudddenly
becoming unlatched and flying somewhere
seems dangerous. I'd rather the ballast be
||My sister-in-law's washer would "walk" when badly unbalanced. One afternoon had her then five-year-old son (kid's 22, now) come running into the living room, announcing, "Mommy, wash machine's comin'!"
||The washer Kevorked itself when it finally advanced far enough to actually pull its own plug! Fortunately, that was before the drain hose came out.
||Are we talking about top loaders or front loaders?
||Top loaders with concrete blocks in them represent an era of engineering typically associated with crude stone tools and uncured animal skins.
||A modern top loader will have a ring-shaped chamber (with baffles) on the bottom and/or top of the inner bowl. This chamber is half-filled with water. Above resonance (say a few tens of rpm) the bowl assembly (included eccentrically positioned clothes) will tend to spin about its center of mass. This means that the relatively unweighted side of the bowl assembly travels through a bigger arc than the weighted side. Because of this, the water in the ring(s) migrates to the relatively unweighted side, counteracting the eccentrically distributed clothes load. This is called passive balancing, and the overall weight of the machine is relatively light.
||What you seem to be describing (controlled filling and draining of separated ballast chambers) is called active balancing. It is typically unnecessary in a toploader (as passive balancing is sufficient).
||Active balancing is significantly more complicated, and has been thought of before.