How Washing Machine's Work

We take a look at the laundry device we couldn't do without.

The principal behind washing cloths is to push water and soap through the fibres of the material, rinse it out and then get out as much excess water as you can prior to drying. While washing machines have advanced a lot their principals of operation have stayed much the same.

The most popular washing machine the top loader can be broken down into a few parts. Firstly the timer is like a clock but with several switches attached to it, when the clock ticks through it various
cycles it can turn on the pump, the inlet valve or the motor. Today many washing machines use a small dedicated processor instead of the mechanical timer, manufacturers find it cheaper to make a circuit board instead of a mechanical part. Also you can add more features easily and sell the computer controlled machine for much more money.

The next major part of the machine is the drum assembly and gear box. The inner drum is where you put your washing it has hundreds of holes in it not only to let the water in but to also force the water out during the spin cycle. If you ever used a centrifuge in science class at school this is what is happening to your washing during the spin cycle. The outer drum is fixed to the washing machine and sits around the inner drum, its purpose is only to hold and catch the water used during the wash cycle.
The plastic part in the centre is called the agitator. The agitator is not attached to the inner drum as it looks, in fact the agitator is capable of turning in opposite directions to the inner drum, it does this via the machines complex gearbox that turns both the inner drum and agitator.

The next parts the washer couldn't do with out are the solenoid valves and pump. the solenoid valves are normally mounted near where the water goes into the machine. they are kind of like your bathroom tap
only they are operated electronically. When the timer get to the stage of the wash cycle that needs water it turns on the solenoid valve so the tub fills with water. A pressure sensor senses when the water is at the desired level and once the tub stops washing the clothes the pump gets switched on to drain out the water, all this is controlled by the timer.

The last thing the machine could not do without is the electric motor that sits at the bottom of the tub and drives the gearbox, the gearbox is often connected to the motor by a belt and both are attached to the outer drum which is connected to the machines cabinet by blocks of rubber. The Rubber helps stop the machine vibrating out of your room during a spin cycle, washing machines often use blocks of concrete to help the stay steady.

Front loaders work in much the same way but they don't need an agitator as the tumbling action of the drum has the same effect of pushing the water through the material. Front loading washing machines have a more elaborate sealing system and interlocked door so water wont spill out of the machine.