Drum brake and method of operating the same

A method of operating a drum brake including a drum including a fastening part fastened to a wheel of a vehicle and a side surface part so that the drum has a cylindrical shape of which one side is open, a pair of brake shoes configured to generate a braking force by rubbing against an inner circumferential surface of the side surface part, a joint rotatably provided on the inner circumferential surface of the side surface part and including a first lever formed to protrude along an outer circumferential surface of each of the brake shoes and a second lever formed to protrude toward an inner surface of the fastening part, and a flap of which one side is fixed to the inner surface of the fastening part and the other side is formed to protrude toward an open surface of the drum,

• wherein:
• in a case in which the drum brake is in a braking state, the first lever is disposed in a horizontal direction;
• and
• in a case in which the drum brake is in a non-braking state, the other side of the flap is bent outward and presses the second lever due to a centrifugal force according to rotation of the drum, and the pressured second lever rotates the joint so that the first lever supports the outer circumferential surface of the brake shoe inward.