Abstract: In a method of manufacturing a brake disc having an outer peripheral shape of projections-recesses repetition in which a radial projection and a radial recess are alternately repeated in the circumferential direction of the brake disc, there is provided a method in which a curved face portion can be formed uniformly over the entire outer peripheral edge portion of the disc main body so as to eliminate the step of chamfering for removing burrs and which is superior in productivity. A disc main body whose outer peripheral shape is projections-recesses repetition is half-blanked from one of plate thickness directions of a sheet material. Thereafter, the disc main body is blanked from the other of the plate thickness directions of the sheet material W.

Abstract: A floating type brake disc is provided which is capable of limiting the heat escape from a rotor to a hub to the extent possible and which can be made smaller in weight. In a plurality of circumferential positions of the hub, there are formed pin-receiving portions in a manner to enclose a connecting pin from three directions of a radially inward, one of circumferentially both sides and a radially outward of the brake disc. A tongue-shaped pin-receiving portion is formed on each of a plurality of inner circumferential positions of the rotor 1 so as to be elongated radially inward to pinch the connecting pin between the tongue-shaped pin-receiving portion and the pin-receiving portion that is formed in the hub.

Abstract: A floating type brake disc is provided which is capable of limiting the heat escape from a rotor to a hub to the extent possible and which can be made smaller in weight. In a plurality of circumferential positions of the hub, there are formed pin-receiving portions in a manner to enclose a connecting pin from three directions of a radially inward, one of circumferentially both sides and a radially outward of the brake disc. A tongue-shaped pin-receiving portion is formed on each of a plurality of inner circumferential positions of the rotor 1 so as to be elongated radially inward to pinch the connecting pin between the tongue-shaped pin-receiving portion and the pin-receiving portion that is formed in the hub.

Abstract: A floating type disc brake “A” used for a vehicle such as a motorcycle comprising a braking rotor 1A and a hub 2A arranged inside the braking rotor 1A, the braking rotor 1A including an annular rotor portion 11 and a plurality of projections 13A extending radially inward from the inner circumferential portion of the rotor portion 11, and further comprising a connecting means 3 for connecting the braking rotor 1A and the hub 2A at positions in which the projections 13A of the braking rotor 1A are abutted to the outer circumferential portion of the hub 2A. At least one of the rotor portion 11 and the projections 13A is formed with cutout portions 13b at the boundary region between the rotor portion 11 and the projections 13A. It is possible to suppress a local heat dissipation in regions of the rotor portion 11 in which the projections 13A are formed and thus to reduce irregularity of heat distribution in the rotor portion 11 during braking operations.

Abstract: A floating type disc brake “A” used for a vehicle such as a motorcycle comprising a braking rotor 1A and a hub 2A arranged inside the braking rotor 1A, the braking rotor 1A including an annular rotor portion 11 and a plurality of projections 13A extending radially inward from the inner circumferential portion of the rotor portion 11, and further comprising a connecting means 3 for connecting the braking rotor 1A and the hub 2A at positions in which the projections 13A of the braking rotor 1A are abutted to the outer circumferential portion of the hub 2A. At least one of the rotor portion 11 and the projections 13A is formed with cutout portions 13b at the boundary region between the rotor portion 11 and the projections 13A. It is possible to suppress a local heat dissipation in regions of the rotor portion 11 in which the projections 13A are formed and thus to reduce irregularity of heat distribution in the rotor portion 11 during braking operations.