A disc brake device includes a rotary member, a brake disc, a control member, and a fastening member. The brake disc includes a disc body having an annular shape and a plurality of fins. The control member includes a base plate and a protruding portion, and controls an airflow rate between the fins disposed adjacent to each other. At least one of the fins has a fastening hole including a small diameter portion. The base plate has a through hole. A shaft portion of the fastening member is inserted through the small diameter portion and the through hole. A peripheral edge of the through hole is disposed on an outer circumferential side of a peripheral edge of the small diameter portion.

A railway wheel includes: a wheel including a plate portion; and a brake disc including a circular plate portion whose front face side is a sliding surface, and a plurality of fin portions which are radially projected on a back face of the circular plate portion, wherein two of the brake discs are fastened in a region within the sliding surface. Regarding an area of a section crossing a space between the brake disc and the wheel along a circumferential direction, a minimum section portion in which the sectional area is minimum is present in a region formed by an outer peripheral surface of the circular plate portion and an inner peripheral surface of the rim portion, and the outer peripheral surface of the circular plate portion follows the inner peripheral surface of the rim portion in a region extending to the outer side from the minimum section portion.

A brake disc of the present invention is a brake disc that stops the rotation of an axle when a brake pad is pressed on a surface of the brake disc, including a disc main body that is attached to a rotary body integrally rotating with the axle; and a plurality of build-up layers laminated on a surface of the disc main body, in which the build-up layers are laminated on the surface of the disc main body by means of laser metal deposition welding.

A brake disk unit includes a rotating member, a brake disk, and a control member. The brake disk includes a disk main body, fins, and convex portions and/or concave portions. The control member includes a support portion and a projecting portion. At least a part of the projecting portion is arranged between fins that are adjacent in the circumferential direction of the brake disk. A gap is formed between the projecting portion and the brake disk. On the surface of the brake disk, the convex portions and/or the concave portions are provided further on the outer side in the radial direction of the brake disk than a minimum opening portion of the gap.

A brake disc for a railway vehicle includes: a disc plate portion that has a sliding portion of a front face; a plurality of radial fins that are provided on the rear face of a disc plate portion, and that have a shape that extends in the radial direction of the disc plate portion; and a circumferential rib that is provided between each pair of adjacent radial fins, and that has a shape that extends in the circumferential direction of the disc plate portion. A flow path for air is formed between the pair of radial fins, and the flow path for air is narrowed by the circumferential rib. On the circumferential rib, a gradual slope for suppressing fluctuations in an airflow that passes between the pair of radial fins is provided from a base part to a top part.

Provided is a high heat resistant brake disk for a railroad vehicle, which is manufactured using a nano material having high heat conductivity, such as a carbon nanotube (CNT) or graphene, to improve heat resistance of an overheated portion of the brake disk, and which can extend a life of the brake disk by suppressing performance deterioration due to a thermal shock. The high heat resistant brake disk includes a hub inserted into an axle of the railroad vehicle and an outer circumference coupled to a vehicle wheel to coaxially rotate with the vehicle wheel, wherein at least one pattern unit made from a high heat resistant nano material is formed on one surface of the brake disk.

A rail wheel having a wheel-mounted brake disk fastened to the wheel body of the rail wheel by multiple fastening elements distributed across the wheel circumference and seated against the wheel body within this fastening region, where the wheel-mounted brake disk is seated against the wheel body in at least one radial area radially outside the fastening region in the cold state and is spaced apart from the wheel body in the region radially within the fastening region to reduce stress on the fastening elements after braking has been initiated.

In order to devise a friction ring body for arrangement on the wheel web of a rail wheel for a rail vehicle for forming a rail wheel brake that can be easily produced, it is proposed that the friction ring body has a friction ring cut out of a flat metal material and a plurality of attachment bodies provided on the friction ring by means of an integrally bonding connection process.

A wheel-mounted brake disk including at least two friction disks, arranged on both sides of a stem of a wheel body of a rail wheel and fastened by fasteners, wherein the at least two friction disks include cooling fins and fastening bosses, wherein the fasteners extend through the fastening bosses of the at least two friction disks and through the stem, wherein the at least two friction disks include round stems, and at least one annular fin, wherein the round stems and the at least one annular fin form the cooling fins.

A wheel brake disc for a wheel of a rail vehicle, wherein the wheel has a wheel web, on which friction rings are supported which are fastened to the wheel web, wherein each friction ring has spring elements arranged in each case on the circumference of the friction rings, wherein, in the mounted state of the wheel brake disc, the spring elements are arranged in each case between the friction rings and the wheel web.