A brake rotor for a braking system of a motor vehicle is provided. The brake rotor includes a disc section for rotating about a longitudinal axis and engaging a brake pad assembly. The brake rotor further includes a hat section for attaching to a wheel. The hat section has a stepped surface spaced from the disc section along the longitudinal axis, and the stepped surface defines a recess for spacing the wheel and a portion of the stepped surface from one another when the wheel is attached to the hat section.

A brake disc assembly includes a central drive hub and a wear disc, which includes first and second faces held together axially about the hub. Each face has a respective inner surface and is formed of at least two distinct segments. Each segment extends between two radial edges. The radial edges of the segments of one face do not extend opposite the radial edges of the segments of the other face. Each segment of the face is adapted to be secured to a segment of the other face via at least one fastening member adapted to hold said faces.

A brake disc assembly includes a central drive hub and a wear disc, which includes first and second faces held together axially about the hub. Each face has a respective inner surface and is formed of at least two distinct segments. Each segment extends between two radial edges. The radial edges of the segments of one face do not extend opposite the radial edges of the segments of the other face. Each segment of the face is adapted to be secured to a segment of the other face via at least one fastening member adapted to hold said faces.

A brake rotor for a braking system of a motor vehicle is provided. The brake rotor includes a disc section for rotating about a longitudinal axis and engaging a brake pad assembly. The brake rotor further includes a hat section for attaching to a wheel. The hat section has a stepped surface spaced from the disc section along the longitudinal axis, and the stepped surface defines a recess for spacing the wheel and a portion of the stepped surface from one another when the wheel is attached to the hat section.

A method is disclosed of retrofitting an elevator machine with primary and secondary braking, the machine being disposed on a machine support frame in an elevator machine room, and engaging one or more ropes for providing selective movement of an elevator car disposed in an elevator shaft, the machine having a drive sheave including a cylindrical brake drum, and brake components including dual brake arms; the method including: removing the brake components; affixing flanged disc segments about the drum and interlocking the flanged disc segments to form a brake rotor; and mounting respective brake calipers to frame mounts for providing primary and secondary braking to the elevator machine.

A brake disc configured to control airflow through portions of a brake disc assembly includes a brake disc, at least one airflow restrictor, and an actuator. The at least one airflow restrictor includes at least one gate member configured to move between a closed position and an open position. In the closed position, the at least one gate member at least partially reduces airflow between a circumferential inner edge and a circumferential outer edge of the brake disc. In the open position, the at least one gate member is positioned to permit increased airflow between the circumferential inner edge and the circumferential outer edge of the brake disc, relative to when the at least one gate member is in the closed position. The actuator is coupled to the at least one airflow restrictor and configured to move the restrictor between the open position and the closed position.

Disclosed are a brake disk and a method for manufacturing the same. In particular, the brake disk may include a friction surface formed of cast iron, and the friction surface of the brake disk is divided into a plurality of sections in a circumferential direction. Preferably, an average of the numbers per unit area of eutectic cells formed on surfaces of the sections may not be greater than 300 ea/cm.sup.2.

A vehicle disc brake unit comprises a rotatable brake rotor and non-rotatable brake pad of caliper. During the vehicle braking, the non-rotatable brake pad presses against the rotating brake rotor, producing friction heat on frictional contact bands where the brake rotor and the brake pad engages with each other. A plurality of longitudinal vortex generators configured in fins is mounted either to a rotatable vehicle component such as hat of a brake rotor, or a non-rotatable vehicle component such as a protective plate, generating longitudinal vortices in the cooling air flows around the brake rotor, especially across the hottest frictional contact bands. The induced longitudinal vortices in the cooling air flows optimize the heat dissipation from brake rotor into atmosphere.

A friction disk may comprise a friction disk core and a wear liner coupled to the friction disk core. A depression may be formed in a surface of the friction disk core. The wear liner may comprise a protrusion extending from a non-wear surface of the wear liner. The protrusion may be positioned within the depression of the friction disk core.

A disc/brake friction torque for railway vehicles consisting of at least one pad comprising at least one friction element and a disc. The friction element is made of a sintered material comprising copper, iron, graphite, 0.02 to 1.5% by weight of molybdenum, 1 to 3% by weight of chrome and a porosity ranging from 20 to 35%; and the disc is made of cast iron comprising 0.05 to 2% by weight of chrome, 0.05 to 2% by weight of molybdenum, 0.1 to 2% by weight of nickel.