Drain plug structure for bath tub
A protrusion of the plug lid out of the bath tub bottom part is restricted to reduce a possibility in which the plug lid becomes a hindrance and a water-tightness at the plug is improved. The plug lid is dropped into the notch formed in such a way that the circumferential edge of the plug lid becomes lower than the bottom surface of the bath tub. The packing is closely contacted with the packing close-contact surface narrowed from the bottom surface of the notch in a downward direction. The bottom part of the notch is formed into the horizontal plane and the plug lid is supported while it is not inclined under application of weight (a hydraulic pressure or an artificial pressure applied by a user) and a non-required crushing force is prevented from being acted on the packing. The anti-vibrating member sliding on the outer circumferential surface of the supporting member for supporting the supporting shaft in such a way it can be moved up and down is mounted vertically at the plug lid to prevent the plug lid from being vibrated, and the foreign material mixing preventive cover having a length extending along an outer circumferential surface of the supporting member prevents the foreign material mixed in the drain water from being entered the supporting member for both cases of opening and closing of the drain port.