To prevent a bicycle for children, a stroller, and a wheelchair from running out of control on a downhill slope due to overspeed by attaching a centrifugal brake thereto to suppress the overspeed.

A gear 1 is mounted on the hub part of a wheel. A ball bearing is fixed to a front fork. The gear 1 is moved when the wheel is rotated to rotate a gear 2. A shaft 4 interlocking with the gear 2 rotates the brake shoe of a centrifugal brake body 5. The brake shoe is expanded by a centrifugal force caused by the rotation to produce a friction on the side surface of a drum. Consequently, the bicycle for children, the stroller, and the wheelchair are prevented from being run out of control on a downhill slope due to overspeed.