This instrument is used for middle school physics teaching demonstrations and group experiments. It is mainly used to illustrate the structure and principle of the suction pump. The products are mainly composed of sink, support rod, cylinder, rocker, connecting rod outlet nozzle, outlet valve, piston and piston ring, inlet valve, etc. When in use, assemble the instrument according to the picture, shake the handle up and down, if it is not flexible, apply a little lubricating oil on the piston ring. Then add water about two-thirds of the depth of the sink into the sink, shake the handle, and the water is continuously pumped up and out of the water outlet. When the piston moves upward from the lower fulcrum, due to atmospheric pressure, the water in the tank is sucked into the cylinder through the water inlet valve. After the piston reaches the upper fulcrum, the water absorption stops. Then, the piston moves from top to bottom. Under the action, the water inlet valve is closed and the water outlet valve is opened. The water enters the upper part of the cylinder through the small hole of the piston. Water overflows from the spout. We attach great importance to customer experience, so you can contact us if you have any questions, and we will get back to you within 24 hours!