In every family, home appliances are quite necessary. They participate a very important element in people's daily life. Meanwhile, the appliances used in the families have some specific requirements. For example, they require for good quality of the products. Besides, low noise, silent running, long life, high quality, energy saving, less friction and space saving are also very important aspects for the home appliances., To meet all these different requirements, every part of the products should be well enough because home appliances are made u
