Drum brake structure

The invention discloses a drum brake structure which comprises a flange portion, a bottom portion, a drum portion and an opening portion. The flange portion is connected with a flange plate of a hub and the bottom portion is connected with the flange portion and the drum portion. The drum brake structure is characterized in that a plurality of hollow portions are arranged on the flange portion, the wall thickness of each hollow portion is smaller than that of the flange portion, and the thickness of the opening portion is 1.7-2 times as much as the average thickness of the drum portion. The top of a drum brake is reinforced, the opening portion is of material stacking and moving design, the wall thickness of the region of stress concentration is enhanced through finite element analysis, hollow thickness-reduction design is conducted on the position near an installation region of a flush bolt at the top, and the drum body middle portion of the drum brake serves as a dynamic balance weight removing region. The weight of the drum brake is kept unchanged, the overall strength is increased and the structure is more reasonable.