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How do washing machines get clothes clean?

Mechanics of Washing Machines

The first thing you see when you open the lid or door to your washing machine is a large drum. The inner part of the drum that you see is often called the basket, and is perforated for water to drain. The outer part of the drum that you can't see is the tub, a solid compartment surrounding the basket that keeps water in or allows it to drain out. The basket can move, but the tub is fixed.

Hoses and pumps move water through the washing machine. When you install the washing machine, you hook hoses up to both hot and cold running water. Another hose takes wastewater that drains from the machine and sends it to a sewer drain pipe. You'll find hot and cold water spigots and a drain pipe ready to use in just about any modern laundry room.

An electric motor in the washing machine moves the basket. If you pick up the repair guide for a washing machine, you'll find detailed terminology and phrases similar to those found in the shop manual for your car. You'll see parts mentioned including belts, hoses, clutch, transmission and even brakes. The motor knows what to do based on the wash program you choose from the buttons and dials on the machine. A combination of digital and mechanical parts carries out that program.

Dispensers let you add detergent, bleach and fabric softener before you start the washing machine so the machine can dispense each of them automatically at the right time. Using dispensers ensures that the detergent mixes thoroughly with the water. Plus, automated dispensers keep clothes from getting spotted from a concentrated splash of bleach or fabric softener.

Washing machines for your home fall into two categories: top-loading and front-loading. They each share the common parts described here, but they have some important differences described on the next page. Washing machines for industrial use, such as in hotels and hospitals, have a lot of the same features on a much larger scale.