Abstract: To provide a metal plate molded article with high vibration damping functionality, a noise-reduction brake disc using the same, and a manufacturing method of a metal plate molded article. A brake disc 20 is composed of a metal plate molded article including an inner member 31 composed of a metal plate and an outer member 32 composed of a metal plate and fitted onto the inner member 31, wherein a friction damping surface 30 is formed in press-contact with fitted surfaces of the inner member 31 and the outer member 32. The brake disc 20 includes a hub part 22 with a plurality of attachment holes 29 into which attachment bolts to a wheel are inserted, and an annular sliding part 21 with a sliding surface 21a with which a brake pad BP is brought into press-contact. The friction damping surface 30 is provided to surround the attachment holes 29 individually or collectively. The inner member 31 and the outer member 32 are formed inside and outside the friction damping surface 30.

Abstract: Provided are a floating brake disk assembling method and a floating brake disk, and a floating brake disk assembling device, wherein a washer or a spring member can be accurately attached to a coupling pin. In the floating disk brake assembling method, a coupling pin 32 for coupling a brake disk (10) to a hub disk (20), which has a cylindrical body portion (41) to be mounted in a coupling hole (31), a first jaw portion (42) formed in one end portion of the body portion (41), and a portion to be swaged (43A) continuous to the other end portion of the body portion (41), is used; and the portion to be swaged (43A) is swaged so that a second jaw portion (42) having a diameter larger than that of the body portion (41) can be formed.

Abstract: A brake disc having reduced noise, configured in such a manner that the generation of noise, such as brake noise, in braking operation is effectively prevented using a simple structure. A brake disc (20) for two-wheeled motor vehicle, provided with a mounting section (12) which is mounted to a wheel, a slide section (11) which slides against a brake pad, a connection section (13) which connects the mounting section (12) and the slide section (11), and weight reducing holes (16) for weight reduction. A slit (21) is formed in the slide section (11). The ratio (L/W) of the length (L) of the slit (21) in the radial direction to the width (W) of the slide section (11) is set in the range of 50-95%, and preferably in the range of 60-90%. The width of the slit (21) is set to 2 mm or less.

Abstract: Provided are a floating brake disk assembling method and a floating brake disk, and a floating brake disk assembling device, wherein a washer or a spring member can be accurately attached to a coupling pin. In the floating disk brake assembling method, a coupling pin 32 for coupling a brake disk (10) to a hub disk (20), which has a cylindrical body portion (41) to be mounted in a coupling hole (31), a first jaw portion (42) formed in one end portion of the body portion (41), and a portion to be swaged (43A) continuous to the other end portion of the body portion (41), is used; and the portion to be swaged (43A) is swaged so that a second jaw portion (42) having a diameter larger than that of the body portion (41) can be formed.

Abstract: A rotary member in the form of a sprocket or a brake disc for transmitting a drive force or brake force, the rotary member having an annular hub portion arranged on a center side, an annular ring portion arranged on an outer circumferential side, and a plurality of arm portions connecting the hub portion and the ring portion, with a plurality of weight reduction holes partitioned by the arm portions between the hub portion and the ring portion. The plurality of arm portions are provided so that centers of their distal end portions on the ring portion side and centers of their proximal end portions on the hub portion side are offset in one circumferential direction, respectively, and the hub portion and the ring portion are not directly connected to each other by longitudinal sectional lines that intersect with the arm portions in a radial direction of the rotary member.

Abstract: A sprocket made of low carbon steel of not more than 0.25 wt % in the carbon content comprising teeth portion which are quenched to a hardness close to the theoretical maximum quenching hardness of 35-55 Rockwell hardness C, and an inside diameter mounting hole.