Drain pipe blockage detection method and device based on capacitance method

The invention provides a drain pipe blockage detection device based on a capacitance method. A round pipeline capacitive sensor structure is arranged on and attached to a pipeline with a round cross section; the capacitive sensor is composed of a pair of two insulated plastic boards with semicircular cross sections; the inner walls of the plastic boards are each provided with a layer of conductive metal (tin) foil in a lining or plating manner; the pair of plastic boards with the semicircular cross sections are fixed through a high-frequency insulating material; and the pair of two oppositely-attached plastic boards provided with metal in the lining or plating manner form two polar plates of the capacitive sensor. Meanwhile, because certain high-frequency capacitor losses exist between the pair of polar plates of the capacitive sensor, the surface layer of conductive metal (such as the tin foil) is further coated with the high-frequency insulating material by us, and the pair of polar plates are connected wit