| 摘要 |
PROBLEM TO BE SOLVED: To provide a brake drum for a vehicle, in which durability can be improved by reducing a stress generated during braking event without increasing manufacturing cost.SOLUTION: A plurality of bolt holes 7 are pierced serially in a circumferential direction in a flange part 6 of a brake drum 5 so as to be fastened to a side of a wheel hub 2 by a hub bolt 9, and a casted surface 5a of an inner circumference is cut while remaining a location in the vicinity of the flange part 6 as cutting stock, thereby forming a slide-contact face 16 with which a brake shoe 11 is brought into slide-contact. Around each of the bolt holes 7 on a right side face of the flange part 6, a circular counter-bored part 17 is formed to which a head 9a of the hub bolt 9 is abutted, respectively, and by forming the circular counter-bored part 17, the casted surface 5a remained as the cutting stock in the vicinity of the flange part 6 is cut off in an arcuate shape in an outer circumferential direction. Thus, thickness of a corner 14 in the circumferential direction of the brake drum 5 is reduced only in an area of the circular counter-bored part 17 (an area of a fastening outer circumferential end 13), thereby suppressing stress generation. |
