Which brand of water purifier water purifier can benefit the investment works of the first stage: microfiltration membranes: microfiltration tap water to remove all kinds of visible / dust and impurities. These particulate matter from aging pipes, rust, roof water tanks secondary pollution and so on. Second level: compression carbon: compressed carbon to remove chlorine and organic contaminants, such as harmful pesticides. Organic compounds in water can absorb odor, color and odor, water disinfection by-products derived from these substances. Water Purifier Working Principle III: UF: ultrafiltration to remove bacteria, viruses and spores and other substances in water. Fourth grade: the filter life indicator: The internal device gear structure design, with the water through, so that an axially inner gear rotates on the motion until the outlet blocked, the flow can not be, that is, through good design travel to calculate the total amount of water through the water purifier to ensure the water is safe. Most of the water purifier is the use of the principle of progressive resistance sieve structure manner, the multi-stage filter inclusive concatenation, precision filters sequentially arranged from low to high, in order to achieve a multi-stage filter assessed trapped dirt, thus reducing filter clogging and artificial sewage, as well as to extend the number of washable filter replacement cycle. There is also a new design idea is to apply the principle of dual circulation self-cleaning structure the way it is designed to provide as much thinking is no longer space for hiding dirt pollutant, but take sub-quality principle, a small isolated part of the clean water, while as usual as far as possible the flow of raw water flow together with the water quality in a timely manner so that dirt is taken away, to water does not rot. This will not only get purified water, they will not or can not easily precipitate dirt in the machine to avoid the formation of secondary contamination and greatly reduce the filter loss, better water quality and more secure and energy-efficient low-carbon. This new principle of self-cleaning water purifier was the seventh International Invention Exhibition Gold Medal, and two out of a structure, which improves the conventional water purifier because one into a structural disadvantages resulting in raw water impurity concentration in the machine piled higher and finally become water, and therefore no self-cleaning water purifier concept sewage and sewage water purifier instead of washing water. With the improvement of living standards, water purifier will become widely popular, new technology products are better meet people's needs.