Attachment structure of brake disk for railway vehicle, and brake disk unit using same

A brake disk unit for a railway vehicle, comprising:

• an annular brake disk;
• an attachment object member, the attachment object member being a wheel of the railway vehicle or a disk body that is to be fixed to an axle of the railway vehicle;
• and
• an attachment structure that attaches the annular brake disk to the attachment object member, the attachment structure comprising:
• a fastening member which fastens the brake disk to the attachment object member, the fastening member having a bolt including a shaft portion that passes through the brake disk and the attachment object member, and a nut that is to be attached to an end part of the shaft portion on the brake disk side;
• and
• an elastic member which is disposed between the nut and the brake disk;
• wherein the elastic member includes:
• a member body which has a tubular shape and into which the shaft portion is inserted,
• a first flange which is connected to an end part on the nut side among two end parts of the member body, a top surface of the first flange coming progressively closer to the nut as the first flange extends toward an outer peripheral side of the elastic member, the first flange protruding outward from the member body and contacting an outer peripheral portion of the nut, and
• an outer peripheral surface of the elastic member includes, in longitudinal sectional view of the elastic member, a first curved portion that connects the member body and the first flange.