Abstract: A friction pad for a disk brake is designed so that a wear sensor can be firmly secured to the friction pad. A circular cylindrical projection is formed on a backing plate of the friction pad by extrusion so that a wear sensor adapted to sound an alarm by coming in contact with a disk is fitted onto the projection and secured to the backing plate by caulking the projection. The projection is so deformed that the diameter d.sub.1 and height h.sub.1 of a resulting radially enlarged portion satisfy the relationship of (d.sub.1 -3.4).times.h.sub.1 .gtoreq.2.5, thereby preventing rotation of the wear sensor and rising of the enlarged portion.

Abstract: A multi-blade fan having a fan assembly including a bottom plate and a plurality of circumferentially spaced blades and a casing for the fan assembly therein having an outlet duct extending therefrom for discharge of the air flows. The fan assembly includes an annular shroud connected to the axial ends of the blades remote from the bottom plate. The casing includes a bottom wall for rotatably connecting the fan assembly, a top wall for defining an air inlet for axially introducing the air into the casing, and a tubular wall connecting the bottom and top walls. The top wall of the casing adjacent to the inlet opening forms an annular projection having a bell cross sectional shape opened inwardly so that an axial end of the shroud extends thereto. The bell cross section portion radially extends to a portion that is inclined downwardly in the outward direction, which faces the shroud so that a small gap extending radially is created.

Abstract: A multi-blade fan having a fan assembly including a bottom plate and a plurality of circumferentially spaced blades and a casing for the fan assembly therein having an outlet duct extending therefrom for discharge of the air flows. The fan assembly includes an annular shroud connected to the axial ends of the blades remote from the bottom plate. The casing includes a bottom wall for rotatably connecting the fan assembly, a top wall for defining an air inlet for axially introducing the air into the casing, and a tubular wall connecting the bottom and top walls. The top wall of the casing adjacent to the inlet opening forms an annular projection having a bell cross sectional shape opened inwardly so that an axial end of the shroud extends thereto. The bell cross section portion radially extends to a portion that is inclined downwardly in the outward direction, which faces the shroud so that a small gap extending radially is created.