Patent: new toilet drainage and exhaust system

Under normal conditions, the check valves 4 of all floors are slightly open, so that the odor air flow can be continuously discharged from the main sewage pipe 2 through the exhaust port 6 through the toilet bowl 5, the check valve 4 and the sewage branch pipe 3 when convenient; When the toilet flushes upstairs, the main sewer pipe 2 forms air backflow, and the one-way valve 4 at the bottom is closed, thus preventing the air flow from entering the toilet through the toilet bowl 5. When flushing the toilet bowl, water passes through the toilet bowl 5, the check valve 4 is opened, then passes through the sewer branch pipe 3 to the sewer main pipe 2, and finally the sewage is discharged into the sewer pipe 7 through the opened check valve 1; In order to prevent the odor in the sewer 7 from being discharged into the surrounding air through the outlet 6 and polluting the environment, the check valve 1 is usually closed (a Z-bend can also be provided). Because the one-way valve is arranged between the sewer branch pipe and the toilet, there will be no backwater when flushing the toilet, so the toilet can be flushed with little or no water, and the water-saving effect is obvious. As another example, the main sewer pipe 2 can be connected with a plurality of branch sewers, so as to be applied to buildings with more floors.