| 摘要 |
A counterflow prevention device of a sewer pipe is provided to prevent the counterflow of sewage by opening a sewage inflow pipe quickly if sewage, river water or sewage flows backward to be drained off smoothly. The counterflow prevention device(100) of a sewer pipe comprises a valve body(101) formed in a horizontal single pipe of a cylindrical cross section and composed of an sewage inflow pipe(110) and a sewage outflow pipe(120), a check valve(104) formed in a semi-cylinder to cover up a through hole of the sewage outflow pipe at ordinary times, a buoyant body(106) attached in the middle of the bottom of the check valve and formed in the enough size to enter a through hole of the sewage outflow pipe, and sensing pipes(108) assembled to the bottom of the valve body and equipped with a counterflow sensing pipe(181). If sewage, river water or sea water flows backward to the sensing pipe, the check valve ascends with the buoyant force of the buoyant body to close a drainage passage between the sewage inflow pipe and the sewage outflow pipe to prevent the counter flow toward the sewage inflow pipe. |
