Piston water pump inlet pipe inserted into the lower part of the body of water is a pump cylinder, a cylinder mounted and can slide up and down with the cylinder wall,close-fitting piston, the piston and the cylinder bottom of each can only open up a shutter v1 and v2. In use,if the piston moves upward by the atmospheric pressure valve v2 is closed, so the thin air under the piston,the air pressure is less than the outside atmospheric pressure.

Thus,the role of water at low atmospheric pressure by pushing the shutter v1 into the barrel. When pressed piston,cylinder bottom valve v1 oppression by water closed,water can not flow down was blocked,then rushed to open the shutter v2 up water into the upper cylinder. When reinstituted pistons, the water above the valve v2 is closed,the water that flows out from the side of the tube,at the same time, the well water and push the shutter v1 at the atmospheric pressure into the pipe. Thus,the piston moves up and down constantly,the water flows from the spout continuous.

This pump is simple in structure, easy to operate, but a small amount of water, water lifting height of only about eight meters, the efficiency is lower. 1,before opening the pump, suction pipe and the pump must be filled with liquid. After opening the pump, high-speed rotation of the impeller,where the blades rotate together with the liquid,the centrifugal force of the impeller fly outward injection, injection of the liquid gradually slow diffusion pump housing indoor speed,gradually increasing the pressure, and then from the pump outlet exhaust pipe outflow. In this case,at the center of the blade due to the surrounding liquid left behind formed neither liquid nor air vacuum area of low pressure liquid liquid pool at the pool surface atmospheric effect, flows into the pump through the suction pipe, so that the liquid is continuously continuously from the liquid bath is drawn up and continuously flows out from the discharge pipe.

Piston pumps, also called draw-type pumps is the use of movement of the piston to discharge the air,causing the air pressure difference between the inside and outside air pressure in the water leaving the rising withdrawn when the piston is depressed,the inlet valve is closed and the exhaust valve opens; when the piston put on,the exhaust valve closes,the inlet valve opens, under atmospheric pressure outside the role of water flow from the inlet valve outlet from the top of the inlet pipe through. Such vertical reciprocating movement of the piston in the cylinder, keep the water out. Note: piston pumps and centrifugal pumps, are the use of atmospheric pressure,the water pumped,because the atmospheric pressure there is a certain limit, and thus pump pumping height there are certain limits,not more than 10.3 meters.