Brake device

A brake device comprising:

• a planetary gear speed reducing mechanism, to which rotation from an electric motor is transmitted, the brake device being configured to convert a rotational motion transmitted from the planetary gear speed reducing mechanism into a linear motion to propel a pressing member, causing a braking member to press a braked member,
• wherein the planetary gear speed reducing mechanism includes
• a shaft portion to which the rotation from the electric motor is transmitted,
• a sun gear to which rotation from the shaft portion is transmitted,
• a plurality of planetary gears meshed with the sun gear and arranged at intervals in a circumferential direction of the sun gear,
• an internal gear including an internal tooth meshed with the planetary gears, the internal gear being arranged to enclose the planetary gears, and
• a speed reducing gear arranged to be concentric with the sun gear and the internal gear,
• wherein the shaft portion extends from the speed reducing gear in an axial direction in a concentric manner,
• wherein the shaft portion has an outer diameter that is smaller than a tip diameter of the sun gear,
• wherein the shaft portion is rotatably supported by the internal gear through a slide bearing,
• wherein the slide bearing comprises a cylindrical bearing portion and an annular flange portion extending from one end of the cylindrical bearing portion in a radially outward direction,
• wherein the cylindrical bearing portion is arranged radially between a cylindrical supporting portion of the internal gear and a base end portion side of the shaft portion, and
• wherein the annular flange portion is held axially between an end surface of the cylindrical supporting portion of the internal gear and a circular ring-like protrusion disposed on an end surface of a circular wall portion of the speed reducing gear.