PURPOSE: A device for maintaining a designated water level of paddy fields is provided to improve reliability and economic feasibility according to reduced maintenance costs by minimizing mechanical operation using mechatronics technologies. CONSTITUTION: A device for maintaining a designated water level of paddy fields comprises multiple wood piles(101), a support unit(126), a protective case(109), a doughnut shaped float(104), a float inducing pipe(124), an a-contact magnetic sensitive lead switch for high water level(108), an a-contact magnetic sensitive lead switch for low water level(106), a protective case cover(112), a water level sensor set(110), a chattering prevention circuit(113), a self hold circuit(116), a water gate, and a DC electric motor. The wood piles are located on the designated paddy floor. The top level of the wood piles is same as the paddy floor and the section of the top level is a horizontal plane. The support unit is coupled to the top level of the multiple wood piles by multiple coupling screws. Permanent magnets loosely formed inside the protective case is embedded in the doughnut shaped float. The float inducing pipe is loosely formed in a hollow part of the doughnut shaped float embedding the permanent magnets. The water level sensor set is comprised of the protective case, the protective case cover, the doughnut shaped float, and the float inducing pipe. The chattering prevention circuit stabilizes unstable output signals of the a-contact magnetic sensitive lead switches for high and low water level. The self hold circuit receives the output signals of the chattering prevention circuit and outputs 1 or O.본 발명은 논물의 소정수위를 유지하는 장치에 관한 것으로, 더욱 상세하게는 논바닥의 소정위치에 형성되는 논물의 고수위 및 저수위 감지기의 출력신호를 메카트로닉스(Mechatronics) 기술을 이용하여 논물의 소정수위를 유지하는 장치에 관한 것이다.이를 위하여 본 발명은 논물의 고수위와 저수위의 감지기 역할을 하는 두 개의 a-접점 자력감응(磁力感應) 리드스위치가 ON(닫힘)될 때, 각각 짧은 시간동안의 불안정한 출력신호로 인해 발생되는 채터링(Chattering) 현상과 논물의 파동에 의한 플로트(Float)의 동요로 인하여 상기 리드스위치가 ON 또는 OFF되어 발생될 수 도 있는 채터링
